A Bladder Stone Masquerading as Recurrent Tumor: A Diagnostic Pitfall in Post-TURBT Surveillance

A Bladder Stone Masquerading as Recurrent Tumor: A Diagnostic Pitfall in Post-TURBT Surveillance | 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 Case Report A Bladder Stone Masquerading as Recurrent Tumor: A Diagnostic Pitfall in Post-TURBT Surveillance Sanjana Kamath Panchmal, Adarsh Sugathan, Saraswathy Sreeram, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6965369/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Lesions arising at sites of prior transurethral resection of bladder tumor (TURBT) are often presumed to indicate tumor recurrence, especially in patients with a known history of urothelial carcinoma. However, non-neoplastic mimics exist, which may lead to overtreatment if not properly identified. Case Presentation: We report the case of an 80-year-old man with a prior diagnosis of low-grade bladder cancer who was found to have a polypoid lesion at the TURBT scar site during routine surveillance. Although malignancy was suspected, biopsy and histological evaluation revealed a crystalline-rich necrotic mass consistent with a cystolith. Conclusion: This rare presentation highlights how bladder stones, particularly when adherent to the urothelial mucosa, can simulate neoplastic polyps. Vigilance and confirmatory pathology are essential in such cases to avoid misdiagnoses. Bladder cancer Cystolith Histopathological examination TURBT Bladder calculus Diagnostic pitfall Figures Figure 1 Figure 2 Figure 3 BACKGROUND The spectrum of urinary bladder tumors ranges from benign papillomas to invasive urothelial carcinoma [1][2]. Bladder stones, or cystoliths, have been recognized since the 5th century BC as noted in the works of Hippocrates. Despite their long history, they remain rare, accounting for only 5% of all urinary tract calculi [3]. Primary bladder stones, which occur without any anatomical, functional, or infectious causes, are typically composed of ammonium urate or calcium oxalate, and infrequently recur post-treatment. Secondary cystoliths are more commonly observed in elderly patients or those with spinal cord injuries, generally associated with bladder outlet obstruction.Historically, bladder calculi or cystolith were prevalent among children in Europe before 1800 and continue to be relatively common in certain regions of Asia and the Middle East. Most affected individuals were boys under the age of 10 years, with stones composed of calcium oxalate and ammonium acid urate, and typically no renal stones present. A diet low in protein and minerals, along with insufficient fluid intake, appears to contribute to stone formation in these children. In North America and Europe, only 2%–3% of bladder calculi cases are pediatric. Bladder stones predominantly affect men with bladder outlet obstruction and their children in developing countries. While most stones are free-floating in the bladder, they can occasionally form around sutures after surgery. The symptoms commonly include hesitancy, frequency, nocturia, hematuria, dysuria, and suprapubic pain radiating to the penis. Diagnostic procedures, such as radiography or cystoscopy, are typically employed, with cystoscopy being particularly definitive because of its ability to detect radiolucent uric acid stones [4,5,6]. The management of bladder calculi typically involves endourological techniques, such as laser cystolithotripsy or percutaneous cystolithotomy. Open transvesical cystolithotomy was reserved for select cases. [7]. CASE PRESENTATION We present an intriguing case involving an 80-year-old diabetic patient who underwent TURBT for a right posterolateral bladder lesion (low-grade carcinoma bladder) six months ago. During follow-up cystourethroscopy, a 1.5x1.5 cm polyp was noted on the scar site. (Fig. 1) Clinical suspicion led to a recurrent malignancy, warranting further investigation. Elevated blood sugar and glycated hemoglobin levels were noted. Urine analysis was within normal limits, cytology was negative for malignant cells, and pH was acidic. Ultrasonography revealed a 1.6 x 1.7 cm polyp in the lateral wall. Biopsies were performed during the cystourethroscopy. Histopathological examination revealed necrotic material, numerous refractile crystalline structures (Figure 2A, B), a foreign body giant cell reaction, and a mixed inflammatory infiltrate. Importantly, no evidence of neoplasms was found. Polarizing microscopy revealed characteristic rosette-like, spherical, wedge-shaped, flat-plated, and spiky thorn-like appearances, leading to the diagnosis of vesical calculus (cystolith). (Fig. 2C, D) The patient was reassured of the absence of malignancy and advised follow-up according to the guidelines. This case underscores the necessity of considering cystoliths in the differential diagnosis of recurrent lesions, especially at previous surgical sites. DISCUSSION AND CONCLUSION Bladder calculi, although historically well-documented, continue to pose diagnostic challenges owing to their ability to mimic neoplastic processes, particularly in patients with a history of bladder malignancy. While their overall prevalence has decreased in developed nations owing to improved nutrition and hygiene, they remain clinically significant in specific populations, including the elderly and individuals with prior urological interventions [2,3]. In the present case, the patient had a history of low-grade urothelial carcinoma for which TURBT was performed. During surveillance, a new lesion was detected at the surgical site, raising immediate suspicion of tumor recurrence. This clinical context naturally leads to a differential dominance by malignancy, given the high rate of recurrence in non-muscle invasive bladder cancer (NMIBC). However, histopathology revealed the lesion to be a cystolith, which is a rare and unexpected finding in this setting. Bladder stone formation at a TURBT site is highly unusual, but can be explained pathophysiologically. Post-surgical changes, such as mucosal injury, local ischemia, or exposure of the muscularis propria, can create a nidus for crystal deposition. Inflammatory exudates or residual suture material may further contribute to stone formation [3,5]. Over time, mineral deposition around this nidus can result in the development of calculus, particularly in patients with risk factors such as poor hydration, urinary stasis, or metabolic derangements such as hyperglycemia, as was seen in this diabetic patient. This case underscores that suspicious lesions warrant prompt endoscopic evaluation, regardless of negative urine cytology or imaging, as subtle lesions may otherwise be missed. Physicians must maintain a high index of suspicion even when the symptoms are mild or atypical. The histological appearance of the bladder polyp in this case was similar to that of a malignant recurrence. However, characteristic features such as necrotic debris, birefringent crystalline structures, foreign body giant cell reaction, and the absence of cytological atypia helped to confirm the benign etiology. Polarizing microscopy findings displaying rosette-like, wedge-shaped, and thorny crystals were indicative of urate-based stones [2,5]. This highlights the essential role of histopathological examination in differentiating benign mimickers from true malignancies, particularly when imaging and endoscopic findings are inconclusive [6]. From a clinical standpoint, bladder cancer recurrence following TURBT is common and typically presents as a papillary growth on cystoscopy. The recurrence rate for low-grade NMIBC can range from 31% to 78%, depending on the tumor size, multiplicity, and initial grade [1]. Therefore, any new lesion, especially at a prior surgical site, requires a high index of suspicion. However, overreliance on endoscopic appearance alone can lead to misdiagnosis and overtreatment. However, this patient was not isolated. Similar results have been reported in the literature. For instance, Schwartz and Stoller noted that calculi could form around surgical material, mimicking neoplasia [3]. As described by Symeonidis et al. [7], delayed diagnosis of recurrent or mimicking lesions can affect outcomes. Stone-like lesions fixed to the bladder mucosa have previously been reported in rare contexts [8], further confirming the need for histological validation. Amin et al. and Cheng et al. also emphasized that some bladder stones may provoke local inflammation and polypoid changes, further complicating the diagnostic process [5,6]. Moreover, infections with urease-producing bacteria, such as Proteus mirabilis can lead to struvite stone formation, particularly in patients undergoing multiple urological interventions or catheterizations [4,6]. This case reinforces the importance of integrating histological assessments with clinical and radiological findings for post-TURBT surveillance. It also prompts clinicians to consider uncommon but benign entities, such as cystoliths, particularly in elderly men with diabetes or metabolic predispositions [3,4]. Detailed patient history, metabolic evaluation, and awareness of rare presentations can guide more precise and conservative management strategies. Moreover, this case highlights the potential underreporting of post-TURBT stone formation, which may be dismissed as insignificant or mistaken for scar tissue or tumor regrowth. There may be a role for future studies or case series exploring the incidence of stone formation at TURBT sites and identifying risk factors associated with this phenomenon [9] This diagnostic dilemma is relevant not only for urologists but also for pathologists and general clinicians. Any new lesion at the prior operative site should be viewed with scrutiny and biopsied. The broader lesson is that atypical presentations, even in expected locations, may reflect benign mimickers and not true recurrence. In conclusion, bladder calculus may masquerade as a recurrent malignancy in patients with prior urothelial carcinoma. Accurate diagnosis through biopsy and detailed histopathological analysis is essential to prevent mismanagement. Vigilance for benign mimickers is imperative in the postoperative surveillance of bladder cancer patients. Awareness of such presentations can aid in preventing unnecessary interventions and anxiety for patients, and ensure appropriate long-term surveillance tailored to actual recurrence risk. Abbreviations TURBT : Transurethral Resection of Bladder Tumor. cm – Centimetres NMIBC : Non-Muscle Invasive Bladder Cancer. Declarations Ethics approval and Consent to participate The Institutional Ethics Committee of KMC Mangalore waived the need for ethical approval. Informed consent was obtained from the patient for participation. The study adhered to Declaration of Helsinki. Consent for publication Informed consent was obtained from the patient for publication of this case report and any accompanying images, and can be provided by the corresponding author upon reasonable request. Clinical trial number Not applicable Availability of data and materials Data sharing is not applicable to this article as no datasets were generated or analysed during the current study Competing interests The authors declare that they have no conflicts of interest. Funding Nil Authors’ contributions SKP Contributed to the conception, data collection, analysis, writing of the original draft, editing, and finalizing the version to be submitted. AS Contributed to the conception of the study, supervised, analyzed, and wrote the original draft, edited, and finalized the version to be submitted. SS wrote the original draft, edited, and finalized the version to be submitted. GGLP supervised the study and edited and finalized the version to be submitted. References Kaufman DS, Shipley WU, Feldman AS. Bladder cancer. Lancet. 2009 Jul 18;374(9685):239-49. Leslie SW, Sajjad H et al.. Bladder Stones. [Updated 2023 Jul 31]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 January. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441944/ Schwartz BF and Stoller ML. The vesical calculus. Urol Clin North Am 2000;27:333-46 Jhamb M, Lin J, Ballow R, Kamat AM, Grossman HB, Wu X. Urinary tract diseases and bladder cancer risk: a case–control study. Causes of cancer and controls. 2007 Oct;18:839-45. Amin MB, Grignon DJ, Srigley JR, Eble JN. Nonneoplastic lesions in the urinary bladder. In: Urological Pathology. Philadelphia : Wolter Kluwers; 2014. p. 315. Cheng L, MacLennan GT, Bostwick DG. Non-neoplastic disorders of the urinary bladder. In: Urologic Surgical Pathology. 4 th Ed. Philadelphia: Elsevier, 2020. P. 218-9. Symeonidis EN, Symeonidis A, Gkekas C, Georgiadis C, Malioris A, Papathanasiou M. Urothelial neoplasm in a 19-year-old male patient with urine discoloration, negative laboratory, and imaging workup: Should we investigate the findings or symptoms?. Clin Case Rep. 2019;7(3):409-412. Symeonidis EN, Memmos D, et al. Jackstone: Calculus "Toy’ in the bladder. A Case Report of Rare Entity and Comprehensive Review of the Literature. Acta Med Litu. 2022;29(1):149-156. Cicione A, DE Nunzio C, Manno S, et al. Bladder stone management: An update. Minerva Urol Nefrol. 2018;70(1):53-65. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6965369","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":492384630,"identity":"d60d2f16-61d3-4a4f-9e36-c5230a00ae4f","order_by":0,"name":"Sanjana Kamath Panchmal","email":"","orcid":"","institution":"Manipal Academy of Higher Education","correspondingAuthor":false,"prefix":"","firstName":"Sanjana","middleName":"Kamath","lastName":"Panchmal","suffix":""},{"id":492384632,"identity":"6470878c-9239-448a-8d97-b183683b64f7","order_by":1,"name":"Adarsh Sugathan","email":"","orcid":"","institution":"Kasturba Medical College Hospital 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site\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6965369/v1/67c6478ff09150c6d6d337da.png"},{"id":88002653,"identity":"36b34126-c1e2-412f-b6a1-f93d7d032105","added_by":"auto","created_at":"2025-07-31 10:28:28","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":782715,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA.\u003c/strong\u003e Necrotic material, numerous refractile crystalline structures (arrow), no evidence of neoplasm (Hematoxylin and Eosin, x10)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eB.\u003c/strong\u003e Necrotic material, numerous refractile crystalline structures (arrow), no evidence of neoplasm (Hematoxylin and Eosin, x20)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6965369/v1/034d9d625b20c3d3d855990d.png"},{"id":88002666,"identity":"22112995-3c4d-4c8e-ab8b-7dff45752375","added_by":"auto","created_at":"2025-07-31 10:28:29","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":857476,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA.\u003c/strong\u003e Polarizing microscopy: rosette-like, spherical, wedge-shaped, flat-plated, and spiky thorn-like (arrow) appearances suggestive of urate crystals (Hematoxylin and Eosin, x4)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eB.\u003c/strong\u003e Polarizing microscopy: rosette-like, spherical, wedge-shaped, flat-plated, and spiky thorn-like (arrow) appearance suggestive of urate crystals (Hematoxylin and Eosin, x10)\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6965369/v1/262d9bb60c705a2b03bac566.png"},{"id":93659177,"identity":"f9bee87c-34d1-4da7-a32f-1e2b57f46c61","added_by":"auto","created_at":"2025-10-16 07:47:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2985147,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6965369/v1/ace603dc-4367-4677-bf3b-d5da488af4bf.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A Bladder Stone Masquerading as Recurrent Tumor: A Diagnostic Pitfall in Post-TURBT Surveillance","fulltext":[{"header":"BACKGROUND","content":"\u003cp\u003eThe spectrum of urinary bladder tumors ranges from benign papillomas to invasive urothelial carcinoma [1][2]. Bladder stones, or cystoliths, have been recognized since the 5th century BC as noted in the works of Hippocrates. Despite their long history, they remain rare, accounting for only 5% of all urinary tract calculi [3]. Primary bladder stones, which occur without any anatomical, functional, or infectious causes, are typically composed of ammonium urate or calcium oxalate, and infrequently recur post-treatment. Secondary cystoliths are more commonly observed in elderly patients or those with spinal cord injuries, generally associated with bladder outlet obstruction.Historically, bladder calculi or cystolith were prevalent among children in Europe before 1800 and continue to be relatively common in certain regions of Asia and the Middle East. Most affected individuals were boys under the age of 10 years, with stones composed of calcium oxalate and ammonium acid urate, and typically no renal stones present. A diet low in protein and minerals, along with insufficient fluid intake, appears to contribute to stone formation in these children. In North America and Europe, only 2%–3% of bladder calculi cases are pediatric. Bladder stones predominantly affect men with bladder outlet obstruction and their children in developing countries. While most stones are free-floating in the bladder, they can occasionally form around sutures after surgery. The symptoms commonly include hesitancy, frequency, nocturia, hematuria, dysuria, and suprapubic pain radiating to the penis. Diagnostic procedures, such as radiography or cystoscopy, are typically employed, with cystoscopy being particularly definitive because of its ability to detect radiolucent uric acid stones [4,5,6].\u003c/p\u003e\n\u003cp\u003eThe management of bladder calculi typically involves endourological techniques, such as laser cystolithotripsy or percutaneous cystolithotomy. Open transvesical cystolithotomy was reserved for select cases. [7].\u003c/p\u003e"},{"header":"CASE PRESENTATION","content":"\u003cp\u003eWe present an intriguing case involving an 80-year-old diabetic patient who underwent TURBT for a right posterolateral bladder lesion (low-grade carcinoma bladder) six months ago. During follow-up cystourethroscopy, a 1.5x1.5 cm polyp was noted on the scar site. (Fig. 1) Clinical suspicion led to a recurrent malignancy, warranting further investigation.\u003c/p\u003e\n\u003cp\u003eElevated blood sugar and glycated hemoglobin levels were noted. Urine analysis was within normal limits, cytology was negative for malignant cells, and pH was acidic. Ultrasonography revealed a 1.6 x 1.7 cm polyp in the lateral wall. Biopsies were performed during the cystourethroscopy.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eHistopathological examination revealed necrotic material, numerous refractile crystalline structures (Figure 2A, B), a foreign body giant cell reaction, and a mixed inflammatory infiltrate. Importantly, no evidence of neoplasms was found. Polarizing microscopy revealed characteristic rosette-like, spherical, wedge-shaped, flat-plated, and spiky thorn-like appearances, leading to the diagnosis of vesical calculus (cystolith). (Fig. 2C, D)\u003c/p\u003e\n\u003cp\u003eThe patient was reassured of the absence of malignancy and advised follow-up according to the guidelines. This case underscores the necessity of considering cystoliths in the differential diagnosis of recurrent lesions, especially at previous surgical sites.\u003c/p\u003e"},{"header":"DISCUSSION AND CONCLUSION","content":"\u003cp\u003eBladder calculi, although historically well-documented, continue to pose diagnostic challenges owing to their ability to mimic neoplastic processes, particularly in patients with a history of bladder malignancy. While their overall prevalence has decreased in developed nations owing to improved nutrition and hygiene, they remain clinically significant in specific populations, including the elderly and individuals with prior urological interventions [2,3].\u003c/p\u003e\n\u003cp\u003eIn the present case, the patient had a history of low-grade urothelial carcinoma for which TURBT was performed. During surveillance, a new lesion was detected at the surgical site, raising immediate suspicion of tumor recurrence. This clinical context naturally leads to a differential dominance by malignancy, given the high rate of recurrence in non-muscle invasive bladder cancer (NMIBC). However, histopathology revealed the lesion to be a cystolith, which is a rare and unexpected finding in this setting.\u003c/p\u003e\n\u003cp\u003eBladder stone formation at a TURBT site is highly unusual, but can be explained pathophysiologically. Post-surgical changes, such as mucosal injury, local ischemia, or exposure of the muscularis propria, can create a nidus for crystal deposition. Inflammatory exudates or residual suture material may further contribute to stone formation [3,5]. Over time, mineral deposition around this nidus can result in the development of calculus, particularly in patients with risk factors such as poor hydration, urinary stasis, or metabolic derangements such as hyperglycemia, as was seen in this diabetic patient.\u003c/p\u003e\n\u003cp\u003eThis case underscores that suspicious lesions warrant prompt endoscopic evaluation, regardless of negative urine cytology or imaging, as subtle lesions may otherwise be missed. Physicians must maintain a high index of suspicion even when the symptoms are mild or atypical.\u003c/p\u003e\n\u003cp\u003eThe histological appearance of the bladder polyp in this case was similar to that of a malignant recurrence. However, characteristic features such as necrotic debris, birefringent crystalline structures, foreign body giant cell reaction, and the absence of cytological atypia helped to confirm the benign etiology. Polarizing microscopy findings displaying rosette-like, wedge-shaped, and thorny crystals were indicative of urate-based stones [2,5]. This highlights the essential role of histopathological examination in differentiating benign mimickers from true malignancies, particularly when imaging and endoscopic findings are inconclusive [6].\u003c/p\u003e\n\u003cp\u003eFrom a clinical standpoint, bladder cancer recurrence following TURBT is common and typically presents as a papillary growth on cystoscopy. The recurrence rate for low-grade NMIBC can range from 31% to 78%, depending on the tumor size, multiplicity, and initial grade [1]. Therefore, any new lesion, especially at a prior surgical site, requires a high index of suspicion. However, overreliance on endoscopic appearance alone can lead to misdiagnosis and overtreatment.\u003c/p\u003e\n\u003cp\u003eHowever, this patient was not isolated. Similar results have been reported in the literature. For instance, Schwartz and Stoller noted that calculi could form around surgical material, mimicking neoplasia [3]. As described by Symeonidis et al. [7], delayed diagnosis of recurrent or mimicking lesions can affect outcomes. Stone-like lesions fixed to the bladder mucosa have previously been reported in rare contexts [8], further confirming the need for histological validation. Amin et al. and Cheng et al. also emphasized that some bladder stones may provoke local inflammation and polypoid changes, further complicating the diagnostic process [5,6]. Moreover, infections with urease-producing bacteria, such as \u003cem\u003eProteus mirabilis\u003c/em\u003e can lead to struvite stone formation, particularly in patients undergoing multiple urological interventions or catheterizations [4,6].\u003c/p\u003e\n\u003cp\u003eThis case reinforces the importance of integrating histological assessments with clinical and radiological findings for post-TURBT surveillance. It also prompts clinicians to consider uncommon but benign entities, such as cystoliths, particularly in elderly men with diabetes or metabolic predispositions [3,4]. Detailed patient history, metabolic evaluation, and awareness of rare presentations can guide more precise and conservative management strategies.\u003c/p\u003e\n\u003cp\u003eMoreover, this case highlights the potential underreporting of post-TURBT stone formation, which may be dismissed as insignificant or mistaken for scar tissue or tumor regrowth. There may be a role for future studies or case series exploring the incidence of stone formation at TURBT sites and identifying risk factors associated with this phenomenon [9]\u003c/p\u003e\n\u003cp\u003eThis diagnostic dilemma is relevant not only for urologists but also for pathologists and general clinicians. Any new lesion at the prior operative site should be viewed with scrutiny and biopsied. The broader lesson is that atypical presentations, even in expected locations, may reflect benign mimickers and not true recurrence.\u003c/p\u003e\n\u003cp\u003eIn conclusion, bladder calculus may masquerade as a recurrent malignancy in patients with prior urothelial carcinoma. Accurate diagnosis through biopsy and detailed histopathological analysis is essential to prevent mismanagement. Vigilance for benign mimickers is imperative in the postoperative surveillance of bladder cancer patients. Awareness of such presentations can aid in preventing unnecessary interventions and anxiety for patients, and ensure appropriate long-term surveillance tailored to actual recurrence risk.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eTURBT\u003c/strong\u003e: Transurethral Resection of Bladder Tumor.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003ecm\u003c/strong\u003e \u0026ndash; Centimetres\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eNMIBC\u003c/strong\u003e: Non-Muscle Invasive Bladder Cancer.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and Consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Institutional Ethics Committee of KMC Mangalore waived the need for ethical approval.\u0026nbsp;Informed consent was obtained from the patient for participation. The study adhered to Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consent was obtained from the patient for publication of this case report and any accompanying images, and can be provided by the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData sharing is not applicable to this article as no datasets were generated or analysed during the current study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNil\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors’ contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSKP Contributed to the conception, data collection, analysis, writing of the original draft, editing, and finalizing the version to be submitted.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAS Contributed to the conception of the study, supervised, analyzed, and wrote the original draft, edited, and finalized the version to be submitted.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSS wrote the original draft, edited, and finalized the version to be submitted.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGGLP supervised the study and edited and finalized the version to be submitted.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eKaufman DS, Shipley WU, Feldman AS. Bladder cancer. Lancet. 2009 Jul 18;374(9685):239-49. \u003c/li\u003e\n\u003cli\u003eLeslie SW, Sajjad H et al.. Bladder Stones. [Updated 2023 Jul 31]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 January. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441944/\u003c/li\u003e\n\u003cli\u003eSchwartz BF and Stoller ML. The vesical calculus. Urol Clin North Am 2000;27:333-46\u003c/li\u003e\n\u003cli\u003eJhamb M, Lin J, Ballow R, Kamat AM, Grossman HB, Wu X. Urinary tract diseases and bladder cancer risk: a case\u0026ndash;control study. Causes of cancer and controls. 2007 Oct;18:839-45.\u003c/li\u003e\n\u003cli\u003eAmin MB, Grignon DJ, Srigley JR, Eble JN. Nonneoplastic lesions in the urinary bladder. In: Urological Pathology. Philadelphia : Wolter Kluwers; 2014. p. 315.\u003c/li\u003e\n\u003cli\u003eCheng L, MacLennan GT, Bostwick DG. Non-neoplastic disorders of the urinary bladder. In: Urologic Surgical Pathology. 4\u003csup\u003eth\u003c/sup\u003e Ed. Philadelphia: Elsevier, 2020. P. 218-9.\u003c/li\u003e\n\u003cli\u003eSymeonidis EN, Symeonidis A, Gkekas C, Georgiadis C, Malioris A, Papathanasiou M. Urothelial neoplasm in a 19-year-old male patient with urine discoloration, negative laboratory, and imaging workup: Should we investigate the findings or symptoms?. Clin Case Rep. 2019;7(3):409-412. \u003c/li\u003e\n\u003cli\u003eSymeonidis EN, Memmos D, et al. Jackstone: Calculus \u0026quot;Toy\u0026rsquo; in the bladder. A Case Report of Rare Entity and Comprehensive Review of the Literature. Acta Med Litu. 2022;29(1):149-156. \u003c/li\u003e\n\u003cli\u003eCicione A, DE Nunzio C, Manno S, et al. Bladder stone management: An update. Minerva Urol Nefrol. 2018;70(1):53-65.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Bladder cancer, Cystolith, Histopathological examination, TURBT, Bladder calculus, Diagnostic pitfall","lastPublishedDoi":"10.21203/rs.3.rs-6965369/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6965369/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003cbr\u003e\n \u003c/strong\u003eLesions arising at sites of prior transurethral resection of bladder tumor (TURBT) are often presumed to indicate tumor recurrence, especially in patients with a known history of urothelial carcinoma. However, non-neoplastic mimics exist, which may lead to overtreatment if not properly\u003c/p\u003e\n\u003cp\u003eidentified.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase Presentation:\u003cbr\u003e\n \u003c/strong\u003eWe report the case of an 80-year-old man with a prior diagnosis of low-grade bladder cancer who was found to have a polypoid lesion at the TURBT scar site during routine surveillance. Although malignancy was suspected, biopsy and histological evaluation revealed a crystalline-rich necrotic mass consistent with a cystolith.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003cbr\u003e\n \u003c/strong\u003eThis rare presentation highlights how bladder stones, particularly when adherent to the urothelial mucosa, can simulate neoplastic polyps. Vigilance and confirmatory pathology are essential in such cases to avoid\u003c/p\u003e\n\u003cp\u003emisdiagnoses.\u003c/p\u003e","manuscriptTitle":"A Bladder Stone Masquerading as Recurrent Tumor: A Diagnostic Pitfall in Post-TURBT Surveillance","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-31 10:28:23","doi":"10.21203/rs.3.rs-6965369/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"599e4cf0-244c-4e10-a6cf-8dfb3c8d0976","owner":[],"postedDate":"July 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-16T07:39:14+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-31 10:28:23","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6965369","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6965369","identity":"rs-6965369","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}