Management of radioiodine ablation therapy in haemodialysis patients with thyroid cancer: a case series of two patients

Management of radioiodine ablation therapy in haemodialysis patients with thyroid cancer: a case series of two patients | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Management of radioiodine ablation therapy in haemodialysis patients with thyroid cancer: a case series of two patients Raymond Lin, Alessandra Malaroda, William J Ryder, Veronica CK Wong, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4161082/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 28 Jul, 2025 Read the published version in BMC Nephrology → Version 1 posted 11 You are reading this latest preprint version Abstract Background Radioiodine ( 131 I) therapy in treatment of thyroid cancer, has a biological clearance that is significantly reduced in end-stage kidney disease (ESKD), leading to increased radiation exposure and potential myelotoxicity. For ESKD patients on haemodialysis (HD), there is no standardized approach to 131 I administration and scheduling of HD following. Methods Two patients with ESKD on HD were treated with 131 I therapy for thyroid cancer. Local 131 I treatment protocol was modified to account for ESKD and HD. Modifications were made to existing infrastructure and additional patient and staff safety precautions were undertaken, including serum 131 I measurements to monitor for myelotoxicity. Results HD at 24-,72- and 144-hours post- 131 I results in a retained radiation activity profile comparable to patients with normal renal function. Radiation dose to bone marrow throughout treatment was assessed at < 0.3 Gy for both patients. The highest contribution of radiation dose to bone marrow (60% and 47% for patient 1 and patient 2 respectively) was due to the radioactivity retained in blood before the first HD session. Cumulative radiation exposure to dialysis staff during therapy was well within local safety constraints. At 18 months post-therapy, remnant thyroid ablation was successful in both patients. Conclusions 131 I therapy can be safely administered in patients with ESKD on HD with modifications to existing infrastructure and protocols. Serum 131 I measurements is a simple and minimally invasive method to assess bone marrow safety during treatment. Ongoing pooling of experiences is needed to inform a standardized protocol for therapy in this population. Haemodialysis radioiodine therapy end-stage kidney disease thyroid cancer nuclear medicine Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Background Ablative radioiodine ( 131 I) therapy with 131 I-sodium iodide following thyroidectomy is often prescribed as standard of care for patients with differentiated thyroid cancer (DTC). As radioactive 131 I is cleared primarily via the kidneys, prolonged blood retention of 131 I in patients with end-stage kidney disease (ESKD) requiring haemodialysis (HD) can result in an increased risk of myelotoxicity( 1 ). For these patients, timing of HD sessions is critical since the extraction efficiency of hemodialysis of the radioactive 131 I is greater than that of normal kidney function and, if not scheduled appropriately, can compromise the efficacy of the treatment. Moreover, in the days immediately after 131 I administration, these patients pose a radiation risk to nursing staff during HD, being themselves a source of g-radiation and from the radioactivity still retained in blood. Radioiodine treatment in HD patients thus presents logistical and clinical challenges for patients and clinical staff. There is limited published guidance in the setup of the treatment protocol for radioablation of thyroid remnants in ESKD patients( 2 , 3 ) and literature is mainly limited to case reports and case series that feature a wide range of protocols and approaches( 4 ). The paucity of literature in treating these patients contributes to the lack of consensus in the optimal treatment schedule to ensure treatment efficacy while limiting risks of myelotoxicity( 5 ). With the objective of contributing our experience to the existing literature and the goal that pooled data from studies may build toward the development of a standardized treatment protocol for this patient population, we report a case series of two HD patients who underwent 131 I therapy in a tertiary centre in Sydney, Australia. The modified protocol for 131 I therapy in HD patients is described, with a report on the outcomes of treatment, and staff and patient safety measures, including whole-body and serum 131 I measurements as the additional safety monitor for myelotoxicity. Methods Population Two HD patients with DTC received post-thyroidectomy adjuvant 131 I therapy. The comparator population was 10 consecutive patients with normal renal function that underwent 131 I therapy for thyroid cancer in the same year at the same centre. Pre-Treatment Preparation Several aspects of HD and 131 I therapy were considered, with modifications made to existing hospital protocols and infrastructure. Room Preparation Specific modifications were made to our hospital’s existing lead-lined room for radioiodine treatment. Plumbing to create a water supply and safe drainage for HD was installed under the supervision of the Radiation Safety Officer. A portable reverse osmosis machine (Baxter/Gambro WRO 300H) for water purification and HD machine (Fresenius Medical Care 5008S) was sourced. An important consideration is the isolation period required for both units after treatment completion; contaminated equipment is typically stored for ten half-lives (approx. three months for 131 I). There was existing closed circuit television (CCTV) monitoring in the room. The treatment room set-up is shown in Fig. 1 . Staff Safety and Education The following additional precautions were instituted to optimise staff safety: Radiation safety education sessions for all staff involved were conducted by the hospital Medical Imaging Physics Service. Disposable personal protective equipment (PPE) was worn at all times within the room (face-shield, mask, gown, double-layered gloves and shoe covers) to protect against splash contamination. HD nursing staff were given electronic personal dosimeters worn underneath PPE to monitor cumulative radiation dose during each HD session. A physicist was available during all HD sessions to monitor staff radiation exposure and intervene in case of radioactive spill/contamination. An area immediately in front of the lead door to the radioiodine room was covered with absorbent paper (Whatman® Benchkote) to allow for assessment of contamination of staff when exiting the room. To minimize staff contact with the patients, patients were assessed for eligibility for self-cannulation and pre-trained if they were suitable. Handling of HD consumables All HD consumables in the 131 I treatment room were prepared and stored in the room before admission of the patient, limiting the time spent by nursing staff in the room during the HD sessions. Following HD, all consumables were disposed in a sharps bin labelled as mixed radioactive-biological waste. The waste was stored for ten half-lives (three months) and disposed as biological waste. Handling of pathology specimens For blood samples (serum biochemistry, full blood counts, coagulation studies) taken during HD, additional provisions were made for handling, isolation, and appropriate disposal in consultation with pathology laboratory staff. Radioactive samples were labelled and safely transported to the laboratory and were processed separately to avoid impacting the results of non-radioactive samples. Once processed, blood samples were collected by Nuclear Medicine staff and disposed appropriately. Other waste Any biological waste, including colostomy bags, were collected in bins labelled as mixed radioactive-biological waste and safely stored for ten half-lives of 131 I (three months). At the end of the storage period, radiation level in the waste was re-assessed and, if decayed below New South Wales (NSW) regulatory limits, disposed as biological waste. Non-biological waste was stored in double-layered bags and disposed of as general waste. Treatment Protocol Pre-treatment 24-hour urine creatinine clearance was measured one week before treatment to determine residual renal function. Pre-treatment with thyrotropin alfa (Sanofi Genzyme – Thyrogen®) to stimulate remaining thyroid cancer cells was given 48-hours before treatment. Thyrogen® dose was reduced to a single intramuscular dose of 0.9mg to account for significantly slower elimination in patients with ESKD( 6 ). Routine HD was performed 24-hours before 131 I therapy. Patients’ usual medications were continued but phosphate binders were withheld for the second patient due to potential binding effect observed with the first patient. Treatment Administered activity of 1GBq was decided based on the American Thyroid Association risk stratification which placed both patients in a low to intermediate risk for recurrence of malignancy. The aim of 131 I therapy was remnant thyroid ablation for both patients. 131 I-sodium iodide was administered orally on Day 0. A nuclear medicine whole body scan was acquired at 4- and 24-hours post-administration and dose-rates at 1m were measured at 1- and 4-hours post-administration. Patients with residual renal function were instructed not to void urine before the dose-rate measurement at 4-hours to allow determination of the calibration factor between administered activity and dose-rate measurement. Routine HD was performed on Days 1, 3 and 6, corresponding to 24-, 72- and 144-hours after 131 I administration. Dose rates at 1m were taken on Days 1, 2, 3 and 6 post- 131 I administration (on HD days ( 1 , 3 and 6 ), the dose-rates were taken both pre- and post-HD). Patients were assessed for potential discharge from Day 3 by the hospital Medical Imaging Physics Service in compliance with state radiation safety legislation ( Radiation Control Act 1990 (NSW), Radiation Control Regulation 2013 (NSW) ). Dose-rate measurements were not scheduled on Days 4 and 5 (Saturday and Sunday) due to resource constraints. If the patient was not discharged on Day 3, they remained in hospital until Day 6. Blood samples for bone marrow dosimetry were collected on HD days (Days 1, 3 and 6) pre- and post-HD. A standard of care nuclear medicine whole body scan was acquired on Day 3. The timeline for the seven-day course of treatment is shown in Fig. 2 . Assessment of radiation dose to bone marrow Approval from the Nepean Blue Mountains Local Health District Human Research Ethics Committee was sought for the collection of data for the assessment of radiation dose to bone marrow. Following the European Association of Nuclear Medicine (EANM) guidance( 7 ), radiation dose to blood was assessed as an upper limit to the radiation dose to bone marrow. Results The baseline characteristics, including cancer staging and HD prescriptions, of the two study patients are shown in Table 1 . Patient 1 was anephric due to bilateral nephrectomy and was undergoing 131 I therapy as a prerequisite for kidney transplantation listing. Patient 2 was morbidly obese (Body Mass Index 50) and had a colostomy in situ. Patient 1 was taught to and successfully self-cannulated for all HD sessions. Table 1 Baseline characteristics, cancer characteristics and haemodialysis prescriptions of two haemodialysis patients undergoing radioiodine therapy. ( AVF = arteriovenous fistula, AJCC = American Joint Committee on Cancer ) Patient 1 Patient 2 Age ( years ) 41 60 Gender Male Male Dry weight ( Kg ) 98 163 Estimated blood volume ( L ) 5.8 7.1 Urine output ( mL/day ) 0 630 24hr urine creatinine clearance ( mL/min ) 0 6 Dialysis duration ( hours ) 5 4.5 Dialysis membrane size ( m 2 ) 2.5 (Solacea 21H) 2.1 (FX CorDiax 120) Blood flow speed ( mL/min ) 300 300 Vascular access type Thyroid cancer type Radiocephalic AVF Papillary Radiocephalic AVF Papillary Lymph node involvement Yes Undefined Stage ( AJCC 8th Edition TNM ) Notable considerations I (T1b, N1, M0) Anephric Transplant candidate II (T2, NX, M0) Morbid obesity Stoma Initial nuclear medicine whole body scan at 4-hours post- 131 I administration for patient 1 appeared to demonstrate pooling of radioactive material in the stomach, later dispersing on scans at 20- and 27-hours. This was postulated to be secondary to the presence of phosphate binders which were subsequently withheld for patient 2. Nuclear medicine whole body scan at Day 3 post- 131 I therapy showed iodine-avid activity in the thyroid bed of both patients, with no activity seen elsewhere. Retained radioactivity (%) as estimated from dose-rate meter measurements at 1m distance over Day 0 to 6 is shown in Fig. 3 . The first sessions of HD resulted in a reduction in radioactivity of 76% and 67% in Patient 1 and 2 respectively. Interdialytic reduction in radioactivity (between HD sessions 1 and 2) was low at 5.2% and 4.7% for patient 1 and 2 respectively. Radiation Dosimetry Total radiation dose to blood was estimated to be < 0.3Gy for both patients, much lower than the accepted maximum tolerated dose to blood of 2.0Gy( 8 ). 60% and 47% of the radiation dose to blood was delivered in the time between 131 I administration and the first HD session, for patient 1 and patient 2 respectively. Treatment Outcomes Remnant thyroid ablation was successful in both patients. Patient 1 demonstrated a sustained reduction in thyroglobulin antibody titre and no evidence of structural disease recurrence. Patient 2 demonstrated sustained undetectable thyroglobulin. Thyroglobulin antibody levels pre- and post-treatment for patient 1 is shown in Fig. 4 . Exposure of Nursing Staff No radioactive contamination was detectable on the nursing staff PPE. Nursing staff exposure to radiation based on personal dosimeter readings is shown in Fig. 5 . Cumulative nursing radiation exposure across 3 sessions of HD was 7µSv and 23µSv for patient 1 and 2 respectively, well within the local dose constraint of 0.5mSv per year for the general public. Actual radiation exposure to individual nurses was even lower as dialysis nurses were rotated at each session. Cumulative radiation exposure for nursing staff assigned to patient 1 was notably lower than staff assigned to patient 2. Equipment and radioactive waste No radioactive contamination was detected on the HD machine, which was safe to be returned to the ward. For each patient, a 12L sharps bin containing HD machine disposables and needles used during dialysis sessions was stored as mixed biological-radioactive waste. A 5L biological waste bin was stored containing stoma bags for patient 2. Discussion In the treatment of DTC in ESKD patients requiring HD, the timing of the first HD session after 131 I administration and, to a lesser extent, the interval between subsequent sessions is critical in maximizing treatment efficacy and minimizing bone marrow toxicity. Previous studies have utilized a range of intervals to the first HD session, varying from 15-hours to 42-hours( 4 ). The interval to subsequent HD sessions has also varied widely in these studies, ranging from 12-hours to 45-hours( 4 ). The rationale behind the choice of HD scheduling in these treatments was dictated by differences in the administered activity of 131 I, readings of dose-rates from the patient, individual patient dialysis requirements, as well as resource availability. The timing of the first HD session after administration is crucial as it determines the majority of radiation dose to the bone marrow. For instance, we found that 60% and 47% of the total radiation dose to bone marrow, for patient 1 and 2 respectively, was delivered in the time between 131 I administration and the first HD session. It follows that increases in the time between 131 I administration and the first HD session will significantly increase the radiation dose delivered to bone marrow. We estimated that the radiation dose delivered to blood was 0.15Gy and 0.1Gy for patients 1 and 2 respectively. If the first HD session were scheduled at 48-hours post-administration instead of 24-hours, we calculated that the radiation dose delivered to bone marrow increases to 0.3Gy and 0.2Gy for patients 1 and 2 respectively. In our study, we found that performing HD sessions at 24-, 72- and 144-hours (Days 1,3 and 6) post- 131 I produced a retained percentage radioactivity profile (i.e., overall clearance rate) similar to profiles of patients with normal renal function (Fig. 3 ). This HD regimen also mirrors the schedule for most patients who undergo 3 times/week intermittent HD, minimizing the risk of emergent dialysis (e.g., for fluid overload, hyperkalaemia) during radioablation treatment. As expected, clearance of 131 I between HD sessions was mainly due to the physical decay of the radionuclide. This is demonstrated through Patient 2, who had a creatinine clearance of 6mL/min, but did not show any greater clearance of radioactivity than Patient 1, who was anephric, indicating that the typical residual renal function of a chronic HD patient is not able to significantly contribute to inter-dialytic 131 I clearance. It should be noted that clearance of 131 I between dialysis depends on 131 I availability in blood and, to a lesser extent, on the amount of 131 I excreted via other means (such as sweat and saliva). The amount of 131 I circulating in blood relates to the volume of residual thyroid tissue after the surgery; patient 2 had greater 131 I uptake in the thyroid bed than patient 1 explaining the lower inter-dialysis clearance. The dosage of 131 I is another uncertain factor, with conflicting evidence on whether to reduce, maintain or increase the standard dose of 131 I given the prolonged half-life and reduced clearance of 131 I in ESKD. Vermandel et al., in a case series of 6 patients, found a 30% reduction to standard 131 I dosing to achieve a balance of treatment efficacy with bone marrow toxicity( 6 ). Holst et al., reached similar conclusions using mathematical modelling( 9 ). Other studies, conversely, have recommended equivalent dosing or increased dosing of 131 I given higher clearance rates on HD and using individualized dosimetry to guide HD scheduling( 10 – 12 ). Although our data is limited to only 2 patients, assuming that HD clearance of 131 I is independent of administered dose, it suggests that the administration of higher levels of radioactivity (up to 4GBq) could be safely given to ESKD patients when the first HD session is scheduled at 24-hours post-administration. Decisions on dosing in this population are beyond the scope of our paper but multidisciplinary input from nuclear medicine specialists, nuclear medicine physicists, endocrinologists and nephrologists is a requirement due to the role of HD in 131 I clearance and the influence on radiation dose to bone marrow. Staff safety is another important consideration when administering 131 I. Patients with normal renal function undergoing 131 I radioablation treatment in hospital are usually isolated with minimal staff contact during their admission. However, patients requiring dialysis represent a deviation from routine practice, as dialysis nursing staff are required to be in close proximity to patients during sessions, when the g-radiation from 131 I may pose a risk. These risks can be significantly mitigated with appropriate distancing, sensible positioning whilst preparing for HD and remote monitoring during HD. In our study, we achieved an overall cumulative radiation exposure to dialysis nursing staff that was very low, consistent with other studies( 3 ). Furthermore, as the closest and most prolonged patient contact occurs during fistula cannulation, if the patient can be safely trained to self-cannulate, we showed that radiation exposure can be reduced even further, seen in the notably lower cumulative staff radiation exposure for patient 1 compared to patient 2 (Fig. 5 ). Finally, our experiences with patient 1 during the study led to additional protocol modifications which were applied to patient 2. One such modification was the suspension of phosphate binders prior to treatment as we suspect this may have resulted in the aggregation of 131 I in the gastrointestinal tract seen on the 4-hour scan for patient 1. There is no literature studying the affinity of phosphate binders with 131 I, but given it is a non-critical medication, withholding all phosphate binders prior to therapy is a reasonable approach. We also found the reduction in thyrotropin alfa to a single dose from the standard of two, produced a more than sufficient response in TSH to proceed with treatment, in agreement with EANM guidance( 6 ). Conclusions The use of radioiodine in patients with ESKD on HD presents logistical hurdles and additional considerations for patient and staff safety. Our study supports the consensus that radioiodine can be safely administered to patients on HD if performed with additional precautions. The existing literature conveys a wide variation in protocols and there is not yet a standardization of approach to therapy in this population. Due to multiple patient variables and differences in resourcing across centers, it is not possible or practical to set out definitive parameters, but rather guidelines and practice points based on multi-center experiences will be invaluable for centers that encounter this scenario for the first time. Our modified protocol outlines one approach to radioiodine in patients on chronic HD to add to published experience and contribute to the future development of standardized guidelines. Abbreviations CCTV Closed circuit television DTC Differentiated thyroid cancer EANM European Association of Nuclear Medicine ESKD End-stage kidney disease HD Haemodialysis 131 I Radioiodine therapy NSW New South Wales PPE Personal protective equipment Declarations Ethics approval and consent to participate All experimental protocols in the study were approved by the Nepean Blue Mountains Local Health District (NBMLHD) Low and Negligible Risk Subcommittee and ratified by the NBMLHD Human Research Ethics Committee (HREC 2022/ETH01125). Informed consent was obtained from all participants in this study prior to collection of any samples or data. Consent for publication Not applicable. Availability of data and materials The datasets analyzed during the current study are not publicly available due to protect patient privacy, but are available from the corresponding author on reasonable request. Competing interests Not applicable Funding Not applicable. Author’s contributions R.L., A.M., W.J.R, V.C.K.W. and N.L.W contributed to conception and design of the study, drafting and editing of the manuscript, providing final approval of published version and agree to be accountable for all aspects of the work involved. A.M. and W.J.R. contributed to data acquisition, analysis and interpretation. Acknowledgements Not applicable. References Sisson JC, Freitas J, McDougall IR, Dauer LT, Hurley JR, Brierley JD, et al. Radiation safety in the treatment of patients with thyroid diseases by radioiodine 131I: practice recommendations of the American Thyroid Association. Thyroid. 2011;21(4):335–46. Luster M, Clarke SE, Dietlein M, Lassmann M, Lind P, Oyen WJ, et al. Guidelines for radioiodine therapy of differentiated thyroid cancer. Eur J Nucl Med Mol Imaging. 2008;35(10):1941–59. Murcutt G, Edwards J, Boakye J, Davenport A. Hemodialysis of chronic kidney failure patients requiring ablative radioiodine therapy. Kidney Int. 2008;73(11):1316–9. Kumar M, Subramanian K, Tanwar KS, Prabhahar A, Divyaveer S, Sood A, et al. Radioiodine Therapy in Patient with Differentiated Thyroid Cancer and End-Stage Renal Disease on Maintenance Hemodialysis: Case Report with Review of Literature. J Nucl Med Technol. 2022;50(3):228–32. Ciarallo A, Rivera J. Radioactive Iodine Therapy in Differentiated Thyroid Cancer: 2020 Update. AJR Am J Roentgenol. 2020;215(2):285–91. Vermandel M, Debruyne P, Beron A, Devos L, Talbot A, Legrand JF, et al. Management of Patients with Renal Failure Undergoing Dialysis During (131)I Therapy for Thyroid Cancer. J Nucl Med. 2020;61(8):1161–70. Lassmann M, Hänscheid H, Chiesa C, Hindorf C, Flux G, Luster M. EANM Dosimetry Committee series on standard operational procedures for pre-therapeutic dosimetry I: blood and bone marrow dosimetry in differentiated thyroid cancer therapy. Eur J Nucl Med Mol Imaging. 2008;35(7):1405–12. Benua RS, Cicale NR, Sonenberg M, Rawson RW. The relation of radioiodine dosimetry to results and complications in the treatment of metastatic thyroid cancer. Am J Roentgenol Radium Ther Nucl Med. 1962;87:171–82. Holst JP, Burman KD, Atkins F, Umans JG, Jonklaas J. Radioiodine therapy for thyroid cancer and hyperthyroidism in patients with end-stage renal disease on hemodialysis. Thyroid. 2005;15(12):1321–31. Morrish DW, Filipow LJ, McEwan AJ, Schmidt R, Murland KR, von Westarp C, Betcher KB. 131I treatment of thyroid papillary carcinoma in a patient with renal failure. Cancer. 1990;66(12):2509–13. Magné N, Magné J, Bracco J, Bussière F. Disposition of radioiodine (131)I therapy for thyroid carcinoma in a patient with severely impaired renal function on chronic dialysis: a case report. Jpn J Clin Oncol. 2002;32(6):202–5. Jiménez RG, Moreno AS, Gonzalez EN, Simón FJL, Rodriguez JR, Jimenez JC, et al. Iodine-131 treatment of thyroid papillary carcinoma in patients undergoing dialysis for chronic renal failure: a dosimetric method. Thyroid. 2001;11(11):1031–4. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 28 Jul, 2025 Read the published version in BMC Nephrology → Version 1 posted Editorial decision: Revision requested 27 Jan, 2025 Reviews received at journal 26 Jan, 2025 Reviewers agreed at journal 08 Jan, 2025 Reviewers agreed at journal 30 Jun, 2024 Reviews received at journal 30 Jun, 2024 Reviewers agreed at journal 28 Jun, 2024 Reviewers invited by journal 28 Jun, 2024 Editor assigned by journal 18 Jun, 2024 Editor invited by journal 01 Apr, 2024 Submission checks completed at journal 01 Apr, 2024 First submitted to journal 25 Mar, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4161082","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":286473988,"identity":"7e8956c5-c714-4515-ac07-9c08a522ef25","order_by":0,"name":"Raymond Lin","email":"data:image/png;base64,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","orcid":"","institution":"Nepean Hospital","correspondingAuthor":true,"prefix":"","firstName":"Raymond","middleName":"","lastName":"Lin","suffix":""},{"id":286473989,"identity":"a9fb5647-bdfd-4a73-80d5-95ba0fb1aa4b","order_by":1,"name":"Alessandra Malaroda","email":"","orcid":"","institution":"Nepean Hospital","correspondingAuthor":false,"prefix":"","firstName":"Alessandra","middleName":"","lastName":"Malaroda","suffix":""},{"id":286473990,"identity":"522b5c45-452d-4a17-bf62-67640e36dc44","order_by":2,"name":"William J Ryder","email":"","orcid":"","institution":"Nepean Hospital","correspondingAuthor":false,"prefix":"","firstName":"William","middleName":"J","lastName":"Ryder","suffix":""},{"id":286473991,"identity":"efd181fe-2ece-47c9-b8f2-01388c4b53eb","order_by":3,"name":"Veronica CK Wong","email":"","orcid":"","institution":"Nepean Hospital","correspondingAuthor":false,"prefix":"","firstName":"Veronica","middleName":"CK","lastName":"Wong","suffix":""},{"id":286473993,"identity":"18201ebe-afb6-45ba-ae27-72caffc8fa85","order_by":4,"name":"Nikki L Wong","email":"","orcid":"","institution":"Nepean Hospital","correspondingAuthor":false,"prefix":"","firstName":"Nikki","middleName":"L","lastName":"Wong","suffix":""}],"badges":[],"createdAt":"2024-03-25 06:29:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4161082/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4161082/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12882-025-04348-0","type":"published","date":"2025-07-28T16:06:09+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":54160956,"identity":"ecc2f742-1b95-4cc3-ab8a-4c964ad1ca48","added_by":"auto","created_at":"2024-04-05 13:03:07","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":254453,"visible":true,"origin":"","legend":"\u003cp\u003eFloor plan of lead-lined treatment room. A – water supply and drainage unit. B – portable reverse osmosis machine. C – haemodialysis machine and chair. D – CCTV monitoring.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4161082/v1/e844c8dea0bf803e8df57006.jpeg"},{"id":54162677,"identity":"168de9ed-8ce4-469b-a864-0b7d7e4f0473","added_by":"auto","created_at":"2024-04-05 13:11:07","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":263284,"visible":true,"origin":"","legend":"\u003cp\u003eRadioiodine treatment timeline. Haemodialysis sessions were carried out on Day -1, 1, 3 and 6. Patients were assessed for potential discharge from Day 3. (*) Dose-rate measurements were not taken on Days 4 and 5 in our study due to resource constraints but should be taken if resources are available to aid earlier hospital discharge.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4161082/v1/742d6e87225d90f06ca67fdf.jpeg"},{"id":54160955,"identity":"b6938a51-a7e6-4190-a3cd-0c4ebf850bad","added_by":"auto","created_at":"2024-04-05 13:03:07","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":388499,"visible":true,"origin":"","legend":"\u003cp\u003eRetained radioactivity (%) over time. Haemodialysis sessions occurred at 24-, 72- and 144-hours post-\u003csup\u003e131\u003c/sup\u003eI administration at 0-hours.\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4161082/v1/d153dd872f864b63c2bf45bb.jpeg"},{"id":54160960,"identity":"959011aa-904c-4bb7-bb4d-30304ad0823b","added_by":"auto","created_at":"2024-04-05 13:03:07","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":149474,"visible":true,"origin":"","legend":"\u003cp\u003eThyroglobulin antibody levels for patient 1. Thyroidectomy is represented by the red arrow and \u003csup\u003e131\u003c/sup\u003eI therapy is represented by the blue arrow.\u003c/p\u003e","description":"","filename":"floatimage5.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4161082/v1/9cabbb9f81118d54aa6c7cef.jpeg"},{"id":54160958,"identity":"218410dd-e7d9-4cac-ad0d-84fa400f83c9","added_by":"auto","created_at":"2024-04-05 13:03:07","extension":"jpeg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":236497,"visible":true,"origin":"","legend":"\u003cp\u003eCumulative radiation exposure to nursing staff across 3 haemodialysis sessions. Local constraints for safe radiation exposure threshold for the general public shown in red dotted line at 500μSv.\u003c/p\u003e","description":"","filename":"floatimage6.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4161082/v1/ce951f38a7e18fa306a92105.jpeg"},{"id":88268295,"identity":"b94d2666-1fe3-4e54-b814-82cf6c3f1b87","added_by":"auto","created_at":"2025-08-04 16:50:47","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1894249,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4161082/v1/829717af-f3a6-4ece-a9b8-c3ba02333385.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Management of radioiodine ablation therapy in haemodialysis patients with thyroid cancer: a case series of two patients","fulltext":[{"header":"Background","content":"\u003cp\u003eAblative radioiodine (\u003csup\u003e131\u003c/sup\u003eI) therapy with \u003csup\u003e131\u003c/sup\u003eI-sodium iodide following thyroidectomy is often prescribed as standard of care for patients with differentiated thyroid cancer (DTC). As radioactive \u003csup\u003e131\u003c/sup\u003eI is cleared primarily via the kidneys, prolonged blood retention of \u003csup\u003e131\u003c/sup\u003eI in patients with end-stage kidney disease (ESKD) requiring haemodialysis (HD) can result in an increased risk of myelotoxicity(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). For these patients, timing of HD sessions is critical since the extraction efficiency of hemodialysis of the radioactive \u003csup\u003e131\u003c/sup\u003eI is greater than that of normal kidney function and, if not scheduled appropriately, can compromise the efficacy of the treatment. Moreover, in the days immediately after \u003csup\u003e131\u003c/sup\u003eI administration, these patients pose a radiation risk to nursing staff during HD, being themselves a source of g-radiation and from the radioactivity still retained in blood. Radioiodine treatment in HD patients thus presents logistical and clinical challenges for patients and clinical staff.\u003c/p\u003e \u003cp\u003eThere is limited published guidance in the setup of the treatment protocol for radioablation of thyroid remnants in ESKD patients(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) and literature is mainly limited to case reports and case series that feature a wide range of protocols and approaches(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). The paucity of literature in treating these patients contributes to the lack of consensus in the optimal treatment schedule to ensure treatment efficacy while limiting risks of myelotoxicity(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). With the objective of contributing our experience to the existing literature and the goal that pooled data from studies may build toward the development of a standardized treatment protocol for this patient population, we report a case series of two HD patients who underwent \u003csup\u003e131\u003c/sup\u003eI therapy in a tertiary centre in Sydney, Australia. The modified protocol for \u003csup\u003e131\u003c/sup\u003eI therapy in HD patients is described, with a report on the outcomes of treatment, and staff and patient safety measures, including whole-body and serum \u003csup\u003e131\u003c/sup\u003eI measurements as the additional safety monitor for myelotoxicity.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePopulation\u003c/h2\u003e \u003cp\u003eTwo HD patients with DTC received post-thyroidectomy adjuvant \u003csup\u003e131\u003c/sup\u003eI therapy. The comparator population was 10 consecutive patients with normal renal function that underwent \u003csup\u003e131\u003c/sup\u003eI therapy for thyroid cancer in the same year at the same centre.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003ePre-Treatment Preparation\u003c/h2\u003e \u003cp\u003eSeveral aspects of HD and \u003csup\u003e131\u003c/sup\u003eI therapy were considered, with modifications made to existing hospital protocols and infrastructure.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eRoom Preparation\u003c/h2\u003e \u003cp\u003eSpecific modifications were made to our hospital\u0026rsquo;s existing lead-lined room for radioiodine treatment. Plumbing to create a water supply and safe drainage for HD was installed under the supervision of the Radiation Safety Officer. A portable reverse osmosis machine (Baxter/Gambro WRO 300H) for water purification and HD machine (Fresenius Medical Care 5008S) was sourced. An important consideration is the isolation period required for both units after treatment completion; contaminated equipment is typically stored for ten half-lives (approx. three months for \u003csup\u003e131\u003c/sup\u003eI). There was existing closed circuit television (CCTV) monitoring in the room. The treatment room set-up is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStaff Safety and Education\u003c/h2\u003e \u003cp\u003eThe following additional precautions were instituted to optimise staff safety:\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eRadiation safety education sessions for all staff involved were conducted by the hospital Medical Imaging Physics Service.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eDisposable personal protective equipment (PPE) was worn at all times within the room (face-shield, mask, gown, double-layered gloves and shoe covers) to protect against splash contamination.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eHD nursing staff were given electronic personal dosimeters worn underneath PPE to monitor cumulative radiation dose during each HD session.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eA physicist was available during all HD sessions to monitor staff radiation exposure and intervene in case of radioactive spill/contamination.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eAn area immediately in front of the lead door to the radioiodine room was covered with absorbent paper (Whatman\u0026reg; Benchkote) to allow for assessment of contamination of staff when exiting the room.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eTo minimize staff contact with the patients, patients were assessed for eligibility for self-cannulation and pre-trained if they were suitable.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eHandling of HD consumables\u003c/h2\u003e \u003cp\u003eAll HD consumables in the \u003csup\u003e131\u003c/sup\u003eI treatment room were prepared and stored in the room before admission of the patient, limiting the time spent by nursing staff in the room during the HD sessions. Following HD, all consumables were disposed in a sharps bin labelled as mixed radioactive-biological waste. The waste was stored for ten half-lives (three months) and disposed as biological waste.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eHandling of pathology specimens\u003c/h2\u003e \u003cp\u003eFor blood samples (serum biochemistry, full blood counts, coagulation studies) taken during HD, additional provisions were made for handling, isolation, and appropriate disposal in consultation with pathology laboratory staff. Radioactive samples were labelled and safely transported to the laboratory and were processed separately to avoid impacting the results of non-radioactive samples. Once processed, blood samples were collected by Nuclear Medicine staff and disposed appropriately.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eOther waste\u003c/h2\u003e \u003cp\u003eAny biological waste, including colostomy bags, were collected in bins labelled as mixed radioactive-biological waste and safely stored for ten half-lives of \u003csup\u003e131\u003c/sup\u003eI (three months). At the end of the storage period, radiation level in the waste was re-assessed and, if decayed below New South Wales (NSW) regulatory limits, disposed as biological waste. Non-biological waste was stored in double-layered bags and disposed of as general waste.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eTreatment Protocol\u003c/h2\u003e \u003cdiv id=\"Sec11\" class=\"Section3\"\u003e \u003ch2\u003ePre-treatment\u003c/h2\u003e \u003cp\u003e24-hour urine creatinine clearance was measured one week before treatment to determine residual renal function. Pre-treatment with thyrotropin alfa (Sanofi Genzyme \u0026ndash; Thyrogen\u0026reg;) to stimulate remaining thyroid cancer cells was given 48-hours before treatment. Thyrogen\u0026reg; dose was reduced to a single intramuscular dose of 0.9mg to account for significantly slower elimination in patients with ESKD(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Routine HD was performed 24-hours before \u003csup\u003e131\u003c/sup\u003eI therapy. Patients\u0026rsquo; usual medications were continued but phosphate binders were withheld for the second patient due to potential binding effect observed with the first patient.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eTreatment\u003c/h2\u003e \u003cp\u003eAdministered activity of 1GBq was decided based on the American Thyroid Association risk stratification which placed both patients in a low to intermediate risk for recurrence of malignancy. The aim of \u003csup\u003e131\u003c/sup\u003eI therapy was remnant thyroid ablation for both patients.\u003c/p\u003e \u003cp\u003e \u003csup\u003e131\u003c/sup\u003eI-sodium iodide was administered orally on Day 0. A nuclear medicine whole body scan was acquired at 4- and 24-hours post-administration and dose-rates at 1m were measured at 1- and 4-hours post-administration. Patients with residual renal function were instructed not to void urine before the dose-rate measurement at 4-hours to allow determination of the calibration factor between administered activity and dose-rate measurement. Routine HD was performed on Days 1, 3 and 6, corresponding to 24-, 72- and 144-hours after \u003csup\u003e131\u003c/sup\u003eI administration.\u003c/p\u003e \u003cp\u003eDose rates at 1m were taken on Days 1, 2, 3 and 6 post-\u003csup\u003e131\u003c/sup\u003eI administration (on HD days (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e and \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e), the dose-rates were taken both pre- and post-HD). Patients were assessed for potential discharge from Day 3 by the hospital Medical Imaging Physics Service in compliance with state radiation safety legislation (\u003cem\u003eRadiation Control Act 1990 (NSW), Radiation Control Regulation 2013 (NSW)\u003c/em\u003e). Dose-rate measurements were not scheduled on Days 4 and 5 (Saturday and Sunday) due to resource constraints. If the patient was not discharged on Day 3, they remained in hospital until Day 6.\u003c/p\u003e \u003cp\u003eBlood samples for bone marrow dosimetry were collected on HD days (Days 1, 3 and 6) pre- and post-HD. A standard of care nuclear medicine whole body scan was acquired on Day 3.\u003c/p\u003e \u003cp\u003eThe timeline for the seven-day course of treatment is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eAssessment of radiation dose to bone marrow\u003c/h2\u003e \u003cp\u003e Approval from the Nepean Blue Mountains Local Health District Human Research Ethics Committee was sought for the collection of data for the assessment of radiation dose to bone marrow. Following the European Association of Nuclear Medicine (EANM) guidance(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e), radiation dose to blood was assessed as an upper limit to the radiation dose to bone marrow.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe baseline characteristics, including cancer staging and HD prescriptions, of the two study patients are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Patient 1 was anephric due to bilateral nephrectomy and was undergoing \u003csup\u003e131\u003c/sup\u003eI therapy as a prerequisite for kidney transplantation listing. Patient 2 was morbidly obese (Body Mass Index 50) and had a colostomy in situ. Patient 1 was taught to and successfully self-cannulated for all HD sessions.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBaseline characteristics, cancer characteristics and haemodialysis prescriptions of two haemodialysis patients undergoing radioiodine therapy. (\u003cem\u003eAVF\u0026thinsp;=\u0026thinsp;arteriovenous fistula, AJCC\u0026thinsp;=\u0026thinsp;American Joint Committee on Cancer\u003c/em\u003e)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePatient 1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePatient 2\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (\u003cem\u003eyears\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e60\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDry weight (\u003cem\u003eKg\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e163\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEstimated blood volume (\u003cem\u003eL\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUrine output (\u003cem\u003emL/day\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e630\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e24hr urine creatinine clearance (\u003cem\u003emL/min\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDialysis duration (\u003cem\u003ehours\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDialysis membrane size (\u003cem\u003em\u003c/em\u003e\u003csup\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.5 (Solacea 21H)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.1 (FX CorDiax 120)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood flow speed (\u003cem\u003emL/min\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVascular access type\u003c/p\u003e \u003cp\u003eThyroid cancer type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRadiocephalic AVF\u003c/p\u003e \u003cp\u003ePapillary\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRadiocephalic AVF\u003c/p\u003e \u003cp\u003ePapillary\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLymph node involvement\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eUndefined\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStage (\u003cem\u003eAJCC 8th Edition TNM\u003c/em\u003e)\u003c/p\u003e \u003cp\u003eNotable considerations\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eI (T1b, N1, M0)\u003c/p\u003e \u003cp\u003eAnephric\u003c/p\u003e \u003cp\u003eTransplant candidate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eII (T2, NX, M0)\u003c/p\u003e \u003cp\u003eMorbid obesity\u003c/p\u003e \u003cp\u003eStoma\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eInitial nuclear medicine whole body scan at 4-hours post-\u003csup\u003e131\u003c/sup\u003eI administration for patient 1 appeared to demonstrate pooling of radioactive material in the stomach, later dispersing on scans at 20- and 27-hours. This was postulated to be secondary to the presence of phosphate binders which were subsequently withheld for patient 2. Nuclear medicine whole body scan at Day 3 post-\u003csup\u003e131\u003c/sup\u003eI therapy showed iodine-avid activity in the thyroid bed of both patients, with no activity seen elsewhere.\u003c/p\u003e \u003cp\u003eRetained radioactivity (%) as estimated from dose-rate meter measurements at 1m distance over Day 0 to 6 is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The first sessions of HD resulted in a reduction in radioactivity of 76% and 67% in Patient 1 and 2 respectively. Interdialytic reduction in radioactivity (between HD sessions 1 and 2) was low at 5.2% and 4.7% for patient 1 and 2 respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eRadiation Dosimetry\u003c/h2\u003e \u003cp\u003eTotal radiation dose to blood was estimated to be \u0026lt;\u0026thinsp;0.3Gy for both patients, much lower than the accepted maximum tolerated dose to blood of 2.0Gy(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). 60% and 47% of the radiation dose to blood was delivered in the time between \u003csup\u003e131\u003c/sup\u003eI administration and the first HD session, for patient 1 and patient 2 respectively.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eTreatment Outcomes\u003c/h2\u003e \u003cp\u003eRemnant thyroid ablation was successful in both patients. Patient 1 demonstrated a sustained reduction in thyroglobulin antibody titre and no evidence of structural disease recurrence. Patient 2 demonstrated sustained undetectable thyroglobulin. Thyroglobulin antibody levels pre- and post-treatment for patient 1 is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eExposure of Nursing Staff\u003c/h2\u003e \u003cp\u003eNo radioactive contamination was detectable on the nursing staff PPE. Nursing staff exposure to radiation based on personal dosimeter readings is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. Cumulative nursing radiation exposure across 3 sessions of HD was 7\u0026micro;Sv and 23\u0026micro;Sv for patient 1 and 2 respectively, well within the local dose constraint of 0.5mSv per year for the general public. Actual radiation exposure to individual nurses was even lower as dialysis nurses were rotated at each session. Cumulative radiation exposure for nursing staff assigned to patient 1 was notably lower than staff assigned to patient 2.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eEquipment and radioactive waste\u003c/h2\u003e \u003cp\u003eNo radioactive contamination was detected on the HD machine, which was safe to be returned to the ward. For each patient, a 12L sharps bin containing HD machine disposables and needles used during dialysis sessions was stored as mixed biological-radioactive waste. A 5L biological waste bin was stored containing stoma bags for patient 2.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn the treatment of DTC in ESKD patients requiring HD, the timing of the first HD session after \u003csup\u003e131\u003c/sup\u003eI administration and, to a lesser extent, the interval between subsequent sessions is critical in maximizing treatment efficacy and minimizing bone marrow toxicity. Previous studies have utilized a range of intervals to the first HD session, varying from 15-hours to 42-hours(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). The interval to subsequent HD sessions has also varied widely in these studies, ranging from 12-hours to 45-hours(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). The rationale behind the choice of HD scheduling in these treatments was dictated by differences in the administered activity of \u003csup\u003e131\u003c/sup\u003eI, readings of dose-rates from the patient, individual patient dialysis requirements, as well as resource availability.\u003c/p\u003e \u003cp\u003eThe timing of the first HD session after administration is crucial as it determines the majority of radiation dose to the bone marrow. For instance, we found that 60% and 47% of the total radiation dose to bone marrow, for patient 1 and 2 respectively, was delivered in the time between \u003csup\u003e131\u003c/sup\u003eI administration and the first HD session. It follows that increases in the time between \u003csup\u003e131\u003c/sup\u003eI administration and the first HD session will significantly increase the radiation dose delivered to bone marrow. We estimated that the radiation dose delivered to blood was 0.15Gy and 0.1Gy for patients 1 and 2 respectively. If the first HD session were scheduled at 48-hours post-administration instead of 24-hours, we calculated that the radiation dose delivered to bone marrow increases to 0.3Gy and 0.2Gy for patients 1 and 2 respectively.\u003c/p\u003e \u003cp\u003eIn our study, we found that performing HD sessions at 24-, 72- and 144-hours (Days 1,3 and 6) post-\u003csup\u003e131\u003c/sup\u003eI produced a retained percentage radioactivity profile (i.e., overall clearance rate) similar to profiles of patients with normal renal function (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). This HD regimen also mirrors the schedule for most patients who undergo 3 times/week intermittent HD, minimizing the risk of emergent dialysis (e.g., for fluid overload, hyperkalaemia) during radioablation treatment. As expected, clearance of \u003csup\u003e131\u003c/sup\u003eI between HD sessions was mainly due to the physical decay of the radionuclide. This is demonstrated through Patient 2, who had a creatinine clearance of 6mL/min, but did not show any greater clearance of radioactivity than Patient 1, who was anephric, indicating that the typical residual renal function of a chronic HD patient is not able to significantly contribute to inter-dialytic \u003csup\u003e131\u003c/sup\u003eI clearance. It should be noted that clearance of \u003csup\u003e131\u003c/sup\u003eI between dialysis depends on \u003csup\u003e131\u003c/sup\u003eI availability in blood and, to a lesser extent, on the amount of \u003csup\u003e131\u003c/sup\u003eI excreted via other means (such as sweat and saliva). The amount of \u003csup\u003e131\u003c/sup\u003eI circulating in blood relates to the volume of residual thyroid tissue after the surgery; patient 2 had greater \u003csup\u003e131\u003c/sup\u003eI uptake in the thyroid bed than patient 1 explaining the lower inter-dialysis clearance.\u003c/p\u003e \u003cp\u003eThe dosage of \u003csup\u003e131\u003c/sup\u003eI is another uncertain factor, with conflicting evidence on whether to reduce, maintain or increase the standard dose of \u003csup\u003e131\u003c/sup\u003eI given the prolonged half-life and reduced clearance of \u003csup\u003e131\u003c/sup\u003eI in ESKD. Vermandel et al., in a case series of 6 patients, found a 30% reduction to standard \u003csup\u003e131\u003c/sup\u003eI dosing to achieve a balance of treatment efficacy with bone marrow toxicity(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Holst et al., reached similar conclusions using mathematical modelling(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Other studies, conversely, have recommended equivalent dosing or increased dosing of \u003csup\u003e131\u003c/sup\u003eI given higher clearance rates on HD and using individualized dosimetry to guide HD scheduling(\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). Although our data is limited to only 2 patients, assuming that HD clearance of \u003csup\u003e131\u003c/sup\u003eI is independent of administered dose, it suggests that the administration of higher levels of radioactivity (up to 4GBq) could be safely given to ESKD patients when the first HD session is scheduled at 24-hours post-administration. Decisions on dosing in this population are beyond the scope of our paper but multidisciplinary input from nuclear medicine specialists, nuclear medicine physicists, endocrinologists and nephrologists is a requirement due to the role of HD in \u003csup\u003e131\u003c/sup\u003eI clearance and the influence on radiation dose to bone marrow.\u003c/p\u003e \u003cp\u003eStaff safety is another important consideration when administering \u003csup\u003e131\u003c/sup\u003eI. Patients with normal renal function undergoing \u003csup\u003e131\u003c/sup\u003eI radioablation treatment in hospital are usually isolated with minimal staff contact during their admission. However, patients requiring dialysis represent a deviation from routine practice, as dialysis nursing staff are required to be in close proximity to patients during sessions, when the g-radiation from \u003csup\u003e131\u003c/sup\u003eI may pose a risk. These risks can be significantly mitigated with appropriate distancing, sensible positioning whilst preparing for HD and remote monitoring during HD. In our study, we achieved an overall cumulative radiation exposure to dialysis nursing staff that was very low, consistent with other studies(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Furthermore, as the closest and most prolonged patient contact occurs during fistula cannulation, if the patient can be safely trained to self-cannulate, we showed that radiation exposure can be reduced even further, seen in the notably lower cumulative staff radiation exposure for patient 1 compared to patient 2 (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eFinally, our experiences with patient 1 during the study led to additional protocol modifications which were applied to patient 2. One such modification was the suspension of phosphate binders prior to treatment as we suspect this may have resulted in the aggregation of \u003csup\u003e131\u003c/sup\u003eI in the gastrointestinal tract seen on the 4-hour scan for patient 1. There is no literature studying the affinity of phosphate binders with \u003csup\u003e131\u003c/sup\u003eI, but given it is a non-critical medication, withholding all phosphate binders prior to therapy is a reasonable approach. We also found the reduction in thyrotropin alfa to a single dose from the standard of two, produced a more than sufficient response in TSH to proceed with treatment, in agreement with EANM guidance(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe use of radioiodine in patients with ESKD on HD presents logistical hurdles and additional considerations for patient and staff safety. Our study supports the consensus that radioiodine can be safely administered to patients on HD if performed with additional precautions.\u003c/p\u003e \u003cp\u003eThe existing literature conveys a wide variation in protocols and there is not yet a standardization of approach to therapy in this population. Due to multiple patient variables and differences in resourcing across centers, it is not possible or practical to set out definitive parameters, but rather guidelines and practice points based on multi-center experiences will be invaluable for centers that encounter this scenario for the first time.\u003c/p\u003e \u003cp\u003e Our modified protocol outlines one approach to radioiodine in patients on chronic HD to add to published experience and contribute to the future development of standardized guidelines.\u003c/p\u003e"},{"header":"Abbreviations","content":" \u003cp\u003eCCTV Closed circuit television\u003c/p\u003e \u003cp\u003eDTC Differentiated thyroid cancer\u003c/p\u003e \u003cp\u003eEANM European Association of Nuclear Medicine\u003c/p\u003e \u003cp\u003eESKD End-stage kidney disease\u003c/p\u003e \u003cp\u003eHD Haemodialysis\u003c/p\u003e \u003cp\u003e \u003csup\u003e131\u003c/sup\u003eI Radioiodine therapy\u003c/p\u003e \u003cp\u003eNSW New South Wales\u003c/p\u003e \u003cp\u003ePPE Personal protective equipment\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cem\u003eEthics approval and consent to participate\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAll experimental protocols in the study were approved by the Nepean Blue Mountains Local Health District (NBMLHD) Low and Negligible Risk Subcommittee and ratified by the NBMLHD Human Research Ethics Committee (HREC 2022/ETH01125). Informed consent was obtained from all participants in this study prior to collection of any samples or data.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent for publication\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAvailability of data and materials\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets analyzed during the current study are not publicly available due to protect patient privacy, but are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCompeting interests\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eFunding\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAuthor\u0026rsquo;s contributions\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eR.L., A.M., W.J.R, V.C.K.W. and N.L.W contributed to conception and design of the study, drafting and editing of the manuscript, providing final approval of published version and agree to be accountable for all aspects of the work involved. A.M. and W.J.R. contributed to data acquisition, analysis and interpretation.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAcknowledgements\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSisson JC, Freitas J, McDougall IR, Dauer LT, Hurley JR, Brierley JD, et al. Radiation safety in the treatment of patients with thyroid diseases by radioiodine 131I: practice recommendations of the American Thyroid Association. Thyroid. 2011;21(4):335\u0026ndash;46.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLuster M, Clarke SE, Dietlein M, Lassmann M, Lind P, Oyen WJ, et al. Guidelines for radioiodine therapy of differentiated thyroid cancer. Eur J Nucl Med Mol Imaging. 2008;35(10):1941\u0026ndash;59.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMurcutt G, Edwards J, Boakye J, Davenport A. Hemodialysis of chronic kidney failure patients requiring ablative radioiodine therapy. Kidney Int. 2008;73(11):1316\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKumar M, Subramanian K, Tanwar KS, Prabhahar A, Divyaveer S, Sood A, et al. Radioiodine Therapy in Patient with Differentiated Thyroid Cancer and End-Stage Renal Disease on Maintenance Hemodialysis: Case Report with Review of Literature. J Nucl Med Technol. 2022;50(3):228\u0026ndash;32.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCiarallo A, Rivera J. Radioactive Iodine Therapy in Differentiated Thyroid Cancer: 2020 Update. AJR Am J Roentgenol. 2020;215(2):285\u0026ndash;91.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVermandel M, Debruyne P, Beron A, Devos L, Talbot A, Legrand JF, et al. Management of Patients with Renal Failure Undergoing Dialysis During (131)I Therapy for Thyroid Cancer. J Nucl Med. 2020;61(8):1161\u0026ndash;70.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLassmann M, H\u0026auml;nscheid H, Chiesa C, Hindorf C, Flux G, Luster M. EANM Dosimetry Committee series on standard operational procedures for pre-therapeutic dosimetry I: blood and bone marrow dosimetry in differentiated thyroid cancer therapy. Eur J Nucl Med Mol Imaging. 2008;35(7):1405\u0026ndash;12.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBenua RS, Cicale NR, Sonenberg M, Rawson RW. The relation of radioiodine dosimetry to results and complications in the treatment of metastatic thyroid cancer. Am J Roentgenol Radium Ther Nucl Med. 1962;87:171\u0026ndash;82.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHolst JP, Burman KD, Atkins F, Umans JG, Jonklaas J. Radioiodine therapy for thyroid cancer and hyperthyroidism in patients with end-stage renal disease on hemodialysis. Thyroid. 2005;15(12):1321\u0026ndash;31.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMorrish DW, Filipow LJ, McEwan AJ, Schmidt R, Murland KR, von Westarp C, Betcher KB. 131I treatment of thyroid papillary carcinoma in a patient with renal failure. Cancer. 1990;66(12):2509\u0026ndash;13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMagn\u0026eacute; N, Magn\u0026eacute; J, Bracco J, Bussi\u0026egrave;re F. Disposition of radioiodine (131)I therapy for thyroid carcinoma in a patient with severely impaired renal function on chronic dialysis: a case report. Jpn J Clin Oncol. 2002;32(6):202\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJim\u0026eacute;nez RG, Moreno AS, Gonzalez EN, Sim\u0026oacute;n FJL, Rodriguez JR, Jimenez JC, et al. Iodine-131 treatment of thyroid papillary carcinoma in patients undergoing dialysis for chronic renal failure: a dosimetric method. Thyroid. 2001;11(11):1031\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-nephrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bnep","sideBox":"Learn more about [BMC Nephrology](http://bmcnephrol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bnep/default.aspx","title":"BMC Nephrology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Haemodialysis, radioiodine therapy, end-stage kidney disease, thyroid cancer, nuclear medicine","lastPublishedDoi":"10.21203/rs.3.rs-4161082/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4161082/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eRadioiodine (\u003csup\u003e131\u003c/sup\u003eI) therapy in treatment of thyroid cancer, has a biological clearance that is significantly reduced in end-stage kidney disease (ESKD), leading to increased radiation exposure and potential myelotoxicity. For ESKD patients on haemodialysis (HD), there is no standardized approach to \u003csup\u003e131\u003c/sup\u003eI administration and scheduling of HD following.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eTwo patients with ESKD on HD were treated with \u003csup\u003e131\u003c/sup\u003eI therapy for thyroid cancer. Local \u003csup\u003e131\u003c/sup\u003eI treatment protocol was modified to account for ESKD and HD. Modifications were made to existing infrastructure and additional patient and staff safety precautions were undertaken, including serum \u003csup\u003e131\u003c/sup\u003eI measurements to monitor for myelotoxicity.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eHD at 24-,72- and 144-hours post-\u003csup\u003e131\u003c/sup\u003eI results in a retained radiation activity profile comparable to patients with normal renal function. Radiation dose to bone marrow throughout treatment was assessed at \u0026lt;\u0026thinsp;0.3 Gy for both patients. The highest contribution of radiation dose to bone marrow (60% and 47% for patient 1 and patient 2 respectively) was due to the radioactivity retained in blood before the first HD session. Cumulative radiation exposure to dialysis staff during therapy was well within local safety constraints. At 18 months post-therapy, remnant thyroid ablation was successful in both patients.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003e \u003csup\u003e131\u003c/sup\u003eI therapy can be safely administered in patients with ESKD on HD with modifications to existing infrastructure and protocols. Serum \u003csup\u003e131\u003c/sup\u003eI measurements is a simple and minimally invasive method to assess bone marrow safety during treatment. Ongoing pooling of experiences is needed to inform a standardized protocol for therapy in this population.\u003c/p\u003e","manuscriptTitle":"Management of radioiodine ablation therapy in haemodialysis patients with thyroid cancer: a case series of two patients","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-04-05 13:03:02","doi":"10.21203/rs.3.rs-4161082/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-01-27T07:14:28+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-01-26T13:50:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"46117349664869455857791343416847809873","date":"2025-01-08T17:20:43+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"247593811095412672070970726137660126721","date":"2024-06-30T22:08:27+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-30T15:40:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"331637876775005381917788951503665042497","date":"2024-06-28T20:32:25+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-06-28T18:36:11+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-06-18T12:25:58+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-04-01T14:15:37+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-04-01T05:05:35+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Nephrology","date":"2024-03-25T06:18:53+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-nephrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bnep","sideBox":"Learn more about [BMC Nephrology](http://bmcnephrol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bnep/default.aspx","title":"BMC Nephrology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f22dfa99-e42e-4a58-a50f-05fc0ba35244","owner":[],"postedDate":"April 5th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-04T16:45:58+00:00","versionOfRecord":{"articleIdentity":"rs-4161082","link":"https://doi.org/10.1186/s12882-025-04348-0","journal":{"identity":"bmc-nephrology","isVorOnly":false,"title":"BMC Nephrology"},"publishedOn":"2025-07-28 16:06:09","publishedOnDateReadable":"July 28th, 2025"},"versionCreatedAt":"2024-04-05 13:03:02","video":"","vorDoi":"10.1186/s12882-025-04348-0","vorDoiUrl":"https://doi.org/10.1186/s12882-025-04348-0","workflowStages":[]},"version":"v1","identity":"rs-4161082","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4161082","identity":"rs-4161082","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}