First Reported Implementation of Lenalidomide as Maintenance Therapy for Metastatic Follicular Dendritic Cell Sarcoma

First Reported Implementation of Lenalidomide as Maintenance Therapy for Metastatic Follicular Dendritic Cell Sarcoma | 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 First Reported Implementation of Lenalidomide as Maintenance Therapy for Metastatic Follicular Dendritic Cell Sarcoma Saarang Kashyap, Esha Sankhala, Ivan Huang, Samuel Liu, Anthony Imani, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6827215/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 Follicular dendritic cell sarcoma (FDCS) is an exceptionally rare, low- to intermediate-grade malignancy arising from mesenchymal-derived follicular dendritic cells, but can present with high-grade pathological features and may rapidly become fatal. Conventional therapeutic strategies, primarily consisting of surgical resection with adjunctive systemic chemotherapy, such as gemcitabine-docetaxel, ifosfamide, doxorubicin, or other regimens, remain inconsistently effective, with median survival notably reduced in advanced or recurrent disease. Given the limited therapeutic options and frequent relapse, there is a critical need for well-tolerated treatments that can improve long term outcomes for patients with metastatic FDCS. Here, we report the first documented clinical use of the immunomodulatory agent Lenalidomide (Revlimid) as maintenance therapy following chemotherapy. Remarkably, the patient achieved nearly total sustained remission with exceptional disease stabilization for approximately six years, experiencing only one manageable recurrence. This clinical response points to lenalidomide as a promising maintenance therapy for metastatic FDCS and may provide further basis for consideration of lenalidomide as a potential first line treatment. Figures Figure 1 Figure 2 Figure 3 Introduction FDCS is a rare type of neoplasm that arises from follicular dendritic cells, which are critical components of the immune system responsible for presenting antigens to B cells within lymph nodes 1 . FDCS accounts for less than 0.4% of all soft tissue sarcomas, and its presentation varies widely depending on the affected site 2 . While most cases occur in lymph nodes, extranodal FDCS has been reported in the liver, pancreas, tonsils, and other organs 3 . Immunohistochemistry is essential for diagnoses, with CD21, D2-40, CD23, and CD35 recognized as key follicular dendritic cell markers 4 5 , and additional markers such as fascin, clusterin, and podoplanin that may further support diagnosis 6 . Although these markers aid in identification, diagnosis remains challenging due to the tumor’s rarity, variable morphology, and lack of distinct clinical features. At the present, the primary approach for treating localized FDCS is surgical resection, representing approximately 85% of all cases, but there is not defined standard of care for metastatic FDCS 7 . However, FDCS recurrence remains common, with pooled analysis showing local recurrence in 28.1% and distant metastasis in 27.2% of patients following initial treatment 8 . For advanced FDCS, various chemotherapy regimens, such as CHOP (cyclophosphamide, doxorubicin, oncovin, and prednisone), gemcitabine, and ifosfamide amongst others have been employed, yet they generally offer only transient disease control and limited success in remission 6 . While some data suggests that radiation therapy (RT) may reduce locoregional recurrence rates, this does not consistently translate into improved disease outcomes. For example, in head and neck FDCS, patients receiving surgery plus RT had lower locoregional recurrence rates (15% for both vs. 45% for surgery) compared to surgery alone; however, there was no significant difference in disease free survival, time to first recurrence, death rate, and 5 year overall survival 9 . Here we present the first documented case of using Lenalidomide as a maintenance therapy in metastatic FDCS. Lenalidomide is an immunomodulatory drug widely used in the treatment of multiple myeloma and certain lymphomas 10 11 . It has several mechanisms of action, including promoting T cell activation, enhancing natural killer (NK) cell activity, and inhibiting angiogenesis 12 . This patient’s sustained response to lenalidomide, with only a single recurrence over a nearly 6 year timespan, suggests that it offers therapeutic benefit as a maintenance strategy in FDCS, particularly when conventional treatments fail to prevent relapse. Case Presentation The patient is a 54-year-old female with past medical history including right breast ductal carcinoma in situ, for which she underwent a right mastectomy and prophylactic left mastectomy with bilateral breast reconstruction in 2011. She was initially referred in June 2015 after a chest X-ray revealed a mass in the left perihilar region. CT and PET scans confirmed a 5 cm, intensely PET-avid left hilar mass, with no evidence of distant disease (Fig. 1 A). The patient underwent a left pneumonectomy in which a large tumor was resected, with clear surgical margins and no involvement of hilar lymph nodes (Fig. 1 B), and final pathology identified her tumor as a high-grade FDCS. The tumor cells demonstrated strong immunohistochemical positivity for CD21, CD23, and CD35 and were negative for keratin and other lineage-specific markers (Fig. 1 C). Additionally, focal expression of D2-40 and TTF-1 was noted, both of which have been previously documented in FDCS 13 14 (Fig. 1 D). Interestingly, the tumor also showed focal aberrant expression of synaptophysin, a neuroendocrine marker not typically associated with FDCS, which may reflect aberrant differentiation and further underscores the tumor’s high-grade, pleomorphic nature (Fig. 1 D). The presence of high-grade features, such as significant cytologic atypia, extensive necrosis, and a high proliferative index indicated a potentially aggressive clinical course (Fig. 2 A). After consultation with sarcoma experts at USC and Cedars-Sinai, adjuvant CHOP chemotherapy was initiated after the left pneumonectomy. However, following her initial cycle of CHOP chemotherapy in early 2016, the patient developed severe side effects, including significant nausea, vomiting, and bone pain. Despite adjustments to antiemetic therapy, she decided to discontinue CHOP after two cycles due to persistent side effects. Follow-up CT scans showed no further evidence of disease progression, and she was transitioned to regular surveillance. In 2017, the patient experienced abdominal pain and bloating. An April PET scan identified a 2.2 cm pelvic mass, and biopsy confirmed FDCS (Fig. 2 B). In November of the same year, she underwent an exploratory laparotomy, which included tumor debulking, a left salpingo-oophorectomy, partial omentectomy, and rectosigmoid resection with low anterior anastomosis. Intraoperatively, multiple tumor nodules were found in the left ovary, fallopian tube, rectal serosa, bladder wall, and sigmoid mesentery. Pathology confirmed metastatic FDCS, and clear margins were achieved in most resected tissues, though the disease was extensive. Postoperatively, the patient received six cycles of paclitaxel and gemcitabine chemotherapy, achieving initial disease stabilization. Due to failure of previous chemotherapy regimens, the patient was started on 20 mg Lenalidomide 4 months after paclitaxel and gemcitabine treatment. This initial regimen led to significant gastrointestinal side effects, prompting a dose reduction to 10 mg daily, which she tolerated well. By 2019, imaging indicated stable disease with no new metastases. A PET scan at the end of the year showed minimal residual metabolic activity. The patient continued on 10 mg of Lenalidomide daily, showing no indication of new metastases through 2020, 2021, and 2022, as confirmed by regular CT and PET scans. In late 2022, a PET scan revealed a moderately to intensely active heterogeneous mass in the splenic hilum, which appeared larger and more active compared to prior imaging, raising strong suspicion of a neoplastic lesion (Fig. 2 C). In January 2023, the patient underwent surgery, which included the excision of the recurrent tumor, an in-continuity distal pancreatectomy and splenectomy, and a partial omentectomy. Pathology confirmed the mass as metastatic FDCS. Following recovery, the patient resumed Revlimid at 10 mg daily, with ongoing regular monitoring showing stable disease and no new activity. Through late 2023 and 2024, PET scans showed no new areas of increased metabolic activity, and there was no reported disease relapse (Fig. 2 D). A chronological overview of the patient’s clinical course, including diagnosis, recurrences, surgical procedures, systemic therapies, and the achievement of disease-free status is given in Fig. 3 . Continuous monitoring with Natera's circulating tumor DNA (ctDNA) testing shows stable ctDNA levels, with no notable increases since early 2023 (Supplemental Fig. 1). Throughout her follow-up visits, the patient has generally reported a good quality of life, managing mild hot flashes and occasional bone pain with over-the-counter medications. She remains physically active, able to exercise regularly without major limitations. Discussion There has been limited exploration into the role of maintenance therapy in FDCS. A recent report described two patients with bulky abdominopelvic FDCS who were treated with a chemoimmunotherapy regimen combining gemcitabine and docetaxel with pembrolizumab 15 . One patient, who achieved a complete metabolic response after six cycles, continued on the same regimen as maintenance therapy. The other patient, who had hepatic metastases, transitioned to pembrolizumab (PD-1 inhibitor) maintenance following initial therapy and demonstrated tumor shrinkage and symptom improvement. Both patients exhibited intermediate PD-L1 expression and sustained clinical responses with good tolerability. In another instance, the use of just pembrolizumab led to complete remission and a progression-free survival of 24 months in a patient with metastatic tonsillar FDCS following chemoradiotherapy 16 . These cases suggest that immunomodulatory treatment has been successful when applied towards FDCS. Considering previous immunotherapy in preventing FDCS spread and recurrence, lenalidomide represents a compelling candidate given its immunomodulatory properties and previously established role in hematologic malignancies 17 . Lenalidomide has become a cornerstone of maintenance therapy in newly diagnosed multiple myeloma (NDMM) following autologous hematopoietic stem cell transplantation (auto-HSCT) 18 19 . Multiple randomized clinical trials, like CALGB 100104, IFM 2005-02, and GIMEMA RV-MM-PI-209, have demonstrated significant progression free survival with hazard ratios of 0.38 and 0.53 in the CALGB and IFM trials, respectively, compared to placebo or no maintenance therapy 20 . A comprehensive patient-level meta-analysis of three randomized controlled trials demonstrated that lenalidomide maintenance therapy following auto-HSCT in newly diagnosed multiple myeloma not only significantly prolonged progression-free survival but also conferred a clinically meaningful overall survival benefit, reducing the risk of death by 25% compared to placebo or observation, with a favorable trend also observed in earlier analyses 21 . While these data show lenalidomide as an important maintenance therapy considering multiple myeloma, the mechanistic rationale for using lenalidomide in FDCS is supported by parallels with follicular lymphoma (FL). Lenalidomide, particularly when combined with rituximab, has significantly improved progression-free survival (PFS) in relapsed or refractory FL, even in rituximab-refractory disease 22 . In the RELEVANCE trial, a combined regimen of rituximab and lenalidomide demonstrated comparable efficacy to rituximab plus chemotherapy in previously untreated FL, with a 3-year PFS rate of 77% and fewer grade 3–4 hematologic toxicities such as neutropenia 23 . Given the overlapping histologic and immunophenotypic features between FDCS and FL, both of which can present as nodular proliferations with spindle or atypical large cells and may express dendritic or lymphoid markers such as CD21, CD35, and S-100, therapies effective in FL may reasonably be considered in FDCS, especially in relapsed or refractory settings 24 25 26 . Lenalidomide offers a sound and potentially well-tolerated therapeutic alternative for patients with FDCS, especially when standard chemotherapy is inadequate or contraindicated. In the case presented here, the use of lenalidomide led to long-term disease stabilization extending through 6 years with one recurrence, suggesting that this immunomodulatory therapy may offer durable control in FDCS. As conventional treatment options remain limited and long-term toxicities of chemotherapy are a concern, the introduction of Lenalidomide as a maintenance therapy may represent a paradigm shift in the management of this rare malignancy. Methods Case Report This case report presents a patient diagnosed and treated for follicular dendritic cell sarcoma (FDCS) at Cedars-Sinai Medical Center, Los Angeles, CA. The patient provided written informed consent for use of anonymized clinical data and imaging for publication. Clinical data were retrospectively collected through comprehensive chart review and included pathology, surgical history, imaging, treatment regimens, laboratory results, and follow-up outcomes. Histopathology and Immunohistochemistry Diagnostic confirmation of FDCS was performed through histopathological evaluation and immunohistochemistry (IHC). Surgical specimens, including pneumonectomy and metastatic tissues, were formalin-fixed and paraffin-embedded (FFPE). Tissue sections (approximately 4 µm thick) were stained with hematoxylin and eosin (H&E) for morphological evaluation. Immunohistochemical staining was conducted using automated platforms at Cedars-Sinai Medical Center, with standard antigen retrieval protocols utilizing heat-induced epitope retrieval (HIER) techniques. The presence of FDCS was verified by diffuse positive staining for follicular dendritic markers (CD21, CD23, CD35), focal positivity for TTF-1 and D2-40, and absence of staining for epithelial (pancytokeratin) and lineage-specific markers (CD3, CD20, CD45, Desmin, S100, Napsin A, PAX-8, among others). Appropriate positive and negative controls were included to ensure the accuracy of staining results. Imaging and Disease Monitoring Longitudinal disease monitoring was conducted via serial 18F-FDG PET/CT and CT scans from 2015 through 2025. Imaging data was collected and reviewed by board-certified radiologists at Cedars-Sinai Medical Center. Imaging studies assessed both metabolic activity and anatomical changes across thoracic, abdominal, and pelvic regions. Circulating tumor DNA (ctDNA) testing (Signatera™, Natera Inc.) was incorporated as a non-invasive method to track minimal residual disease and treatment response from 2023 onward. Data Availability The study data will be made available upon request to the corresponding author. Declarations Author Contributions Statement K.K.S. provided clinical care and treatment for the patient. K.K.S. and S.K. conceptualized the study. S.K. and E.S. were responsible for data collection and S.K. was responsible for all figure (Fig 1-3 and Supplemental Figure) creation. Manuscript writing was conducted by S.K., E.S., I.H., S.L., A.I., J.H., M.B., M.L., and B.H. All authors reviewed the manuscript. Funding Declaration We do not have external funding for this research. Ethics Statement and Consent to Publish Declaration The patient provided written informed consent for the use of anonymized clinical data and imaging for publication. Clinical trial number: not applicable. References Kairouz, S., Hashash, J., Kabbara, W., McHayleh, W. & Tabbara, I.A. Dendritic cell neoplasms: An overview. American Journal of Hematology 82 , 924–928 (2007). Jain, P., et al. Characteristics, management, and outcomes of patients with follicular dendritic cell sarcoma. British Journal of Haematology 178 , 403–412 (2017). Zhao, X., Sun, D. & Zhang, G. Clinicopathological characteristics of extranodal follicular dendritic cell sarcoma: A report of two cases. Oncology Letters 21 (2021). Sood, R. & Mehta, A. Histopathological and immunohistochemical clues to the illusive diagnosis of follicular dendritic cell sarcoma: A clinicopathological masquerader. Indian Journal of Cancer 59 (2022). Jing, Y., Ye, H., Luo, S. & Wang, J. Description of two cases of follicular dendritic cell sarcoma, including next-generation sequencing analysis. Diagnostic Pathology 20 (2025). Sasaki, M., Izumi, H., Yokoyama, T., Kojima, M. & Hosono, A. Follicular dendritic cell sarcoma treated with a variety of chemotherapy. Hematological Oncology 35 , 905–908 (2017). Soriano, A.O., et al. Follicular dendritic cell sarcoma: A report of 14 cases and a review of the literature. American Journal of Hematology 82 , 725–728 (2007). Saygin, C., Uzunaslan, D., Ozguroglu, M., Senocak, M. & Tuzuner, N. Dendritic cell sarcoma: A pooled analysis including 462 cases with presentation of our case series. Critical Reviews in Oncology/Hematology 88 , 253–271 (2013). Pang, J., et al. Follicular dendritic cell sarcoma of the head and neck: Case report, literature review, and pooled analysis of 97 cases. Head & Neck 38 , E2241-E2249 (2016). Zhang, C.-W., Wang, Y.-N. & Ge, X.-L. Lenalidomide use in multiple myeloma (Review). Molecular and Clinical Oncology 20 (2023). Holstein, S.A. & McCarthy, P.L. Immunomodulatory Drugs in Multiple Myeloma: Mechanisms of Action and Clinical Experience. Drugs 77 , 505–520 (2017). Semeraro, M. & Galluzzi, L. Novel insights into the mechanism of action of lenalidomide. OncoImmunology 3 , e28386 (2014). Emechebe, D.Y., Dodd, L., Villalobos, A. & Zhu, L.C. Cytological diagnosis of follicular dendritic cell sarcoma with a unique pattern of D2-40 immunoexpression. Diagnostic Cytopathology 52 (2024). Lopez-Hisijos, N., Omman, R., Pambuccian, S. & Mirza, K. Follicular Dendritic Cell Sarcoma or Not? A Series of 5 Diagnostically Challenging Cases. Clinical Medicine Insights: Oncology 13 , 117955491984453 (2019). Sahin, B. & Guvenc, B. 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McCarthy, P.L., et al. Lenalidomide Maintenance After Autologous Stem-Cell Transplantation in Newly Diagnosed Multiple Myeloma: A Meta-Analysis. Journal of Clinical Oncology 35 , 3279–3289 (2017). Blair, H.A. Lenalidomide: A Review in Previously Treated Follicular Lymphoma. Drugs 80 , 1337–1344 (2020). Morschhauser, F., et al. Rituximab plus Lenalidomide in Advanced Untreated Follicular Lymphoma. New England Journal of Medicine 379 , 934–947 (2018). Younes, S., Rojansky, R.B., Menke, J.R., Gratzinger, D. & Natkunam, Y. Pitfalls in the Diagnosis of Nodular Lymphocyte Predominant Hodgkin Lymphoma: Variant Patterns, Borderlines and Mimics. Cancers 13 , 3021 (2021). Said, J. Follicular lymphomas and histiocytic/dendritic neoplasms related? Blood 111 , 5418–5419 (2008). Kurshumliu, F., et al. Divergent immunohistochemical expression of CD21 and CD23 by follicular dendritic cells with increasing grade of follicular lymphoma. World Journal of Surgical Oncology 17 (2019). Additional Declarations No competing interests reported. Supplementary Files SupplementaryFigures.pdf 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-6827215","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":478860416,"identity":"80be313f-f202-45f8-b7c5-02c22fdef32f","order_by":0,"name":"Saarang Kashyap","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2klEQVRIiWNgGAWjYDACHgYGZgYDGzkw5wGIOECUloI0YzAngXgtHw4nNhCtRb7n8OPPBQbM6fMdeAw/JNQwyPHdSMCvxeBsm5n0DAO23I0HeIwlEo4xGEsS1MLPYMbMY8CTu7GBx4whgY0hcQMhLfL97J8/8xhIpBuCtfxjqCeoheFsj4E0j4FBgjwDUEtiG0OCAUGHnTlTBtSSYLiBma1YIrFPwnDmmQcEHNaTvvkzz5//8vLtzRs/fPhmI893nJDD4NYdBlMSRCoHW9dAguJRMApGwSgYWQAAE8U/3GhaOkQAAAAASUVORK5CYII=","orcid":"","institution":"University of California","correspondingAuthor":true,"prefix":"","firstName":"Saarang","middleName":"","lastName":"Kashyap","suffix":""},{"id":478860417,"identity":"f865da9e-ca84-469c-9ab3-e829d52abaeb","order_by":1,"name":"Esha Sankhala","email":"","orcid":"","institution":"University of Queensland","correspondingAuthor":false,"prefix":"","firstName":"Esha","middleName":"","lastName":"Sankhala","suffix":""},{"id":478860418,"identity":"77caef23-dfb3-405b-bb11-1a9d1afbbed4","order_by":2,"name":"Ivan Huang","email":"","orcid":"","institution":"University of California","correspondingAuthor":false,"prefix":"","firstName":"Ivan","middleName":"","lastName":"Huang","suffix":""},{"id":478860423,"identity":"0a31d39b-45fa-44ac-a0e4-b9517aec8391","order_by":3,"name":"Samuel Liu","email":"","orcid":"","institution":"University of California","correspondingAuthor":false,"prefix":"","firstName":"Samuel","middleName":"","lastName":"Liu","suffix":""},{"id":478860424,"identity":"dbebeb56-c58c-4733-ab22-56691d782e0a","order_by":4,"name":"Anthony Imani","email":"","orcid":"","institution":"University of California","correspondingAuthor":false,"prefix":"","firstName":"Anthony","middleName":"","lastName":"Imani","suffix":""},{"id":478860425,"identity":"ad9a7ce7-8246-4299-9c3f-cabcdf6db99a","order_by":5,"name":"James Heeter","email":"","orcid":"","institution":"University of California","correspondingAuthor":false,"prefix":"","firstName":"James","middleName":"","lastName":"Heeter","suffix":""},{"id":478860426,"identity":"ca020b48-adfb-4513-be52-8161830e846e","order_by":6,"name":"Michael Blekherman","email":"","orcid":"","institution":"University of California","correspondingAuthor":false,"prefix":"","firstName":"Michael","middleName":"","lastName":"Blekherman","suffix":""},{"id":478860427,"identity":"c686c6fe-14e8-4bf7-9493-329025500b01","order_by":7,"name":"Matt Lawson","email":"","orcid":"","institution":"University of California","correspondingAuthor":false,"prefix":"","firstName":"Matt","middleName":"","lastName":"Lawson","suffix":""},{"id":478860428,"identity":"8f56ea71-a7ca-451d-9ad7-02c6a8c11d80","order_by":8,"name":"Brian Hang","email":"","orcid":"","institution":"University of California, Los Angeles","correspondingAuthor":false,"prefix":"","firstName":"Brian","middleName":"","lastName":"Hang","suffix":""},{"id":478860429,"identity":"ddae4685-fe26-4a76-86af-cb66aa36f69d","order_by":9,"name":"Kamalesh K. Sankhala","email":"","orcid":"","institution":"Cedars Sinai Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Kamalesh","middleName":"K.","lastName":"Sankhala","suffix":""}],"badges":[],"createdAt":"2025-06-05 08:53:29","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6827215/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6827215/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":85992326,"identity":"e4991d4a-c8b1-497f-ab62-8d063730e387","added_by":"auto","created_at":"2025-07-04 05:33:38","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":24168497,"visible":true,"origin":"","legend":"\u003cp\u003e(A) PET scan showing initial diagnosis of FDCS as a hypermetabolic left hilar mass. (B) Gross image of left pneumonectomy specimen demonstrating a 4.9 cm heterogeneous hilar mass inseparable from the left upper lobe and mediastinum (C) Immunohistochemistry (IHC) shows tumor cell positivity for follicular dendritic cell sarcoma (FDCS) markers CD21, CD23, and CD35. (D) Immunohistochemistry shows focal positivity of D2-40, TTF-1 and synaptophysin. These findings support the diagnosis of FDCS metastatic to lung, consistent with high-grade malignant features and aberrant lineage marker expression.\u003c/p\u003e","description":"","filename":"Figure1FinalV2.png","url":"https://assets-eu.researchsquare.com/files/rs-6827215/v1/d347c3fb24bfd2ce8868ef06.png"},{"id":85992323,"identity":"00c13aed-9e5b-43d9-a9ca-56a2b07fe2bc","added_by":"auto","created_at":"2025-07-04 05:33:38","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":16156447,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Hematoxylin and eosin (H\u0026amp;E) staining at 40x magnification reveals epithelioid and spindle cells with marked cytologic atypia and areas of necrosis.(B) First recurrence of FDCS identified by PET scan, demonstrating a new hypermetabolic metastatic lesion in the left pelvis a year after patient received 2 cycles CHOP chemotherapy. (C) PET scan capturing subsequent recurrence as an intensely active, heterogeneous mass at the splenic hilum after nearly 4 years treatment with Lenalidomide. (D) Follow-up PET imaging showing no evidence of recurrent or active disease following ongoing Lenalidomide therapy at present.\u003c/p\u003e","description":"","filename":"Figure2FinalV2.png","url":"https://assets-eu.researchsquare.com/files/rs-6827215/v1/068312aba328655b4302ad7a.png"},{"id":85992322,"identity":"8301411c-061c-4967-9533-7b4ddc5c3364","added_by":"auto","created_at":"2025-07-04 05:33:38","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":2428096,"visible":true,"origin":"","legend":"\u003cp\u003eTimeline illustrating the patient's clinical course from initial follicular dendritic cell sarcoma (FDCS) diagnosis through sequential recurrences, surgical interventions, systemic treatments, and current disease-free status\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure3Final.png","url":"https://assets-eu.researchsquare.com/files/rs-6827215/v1/d3c1cbc963517542d62b9559.png"},{"id":92091620,"identity":"3c210dbc-ea9e-4386-9912-8b20fa8010f2","added_by":"auto","created_at":"2025-09-24 13:47:56","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":39527306,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6827215/v1/096526c8-6e33-4124-9a32-41b4e2445c21.pdf"},{"id":85992321,"identity":"5989a94d-769d-4349-9ffe-430051c4c495","added_by":"auto","created_at":"2025-07-04 05:33:38","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":128097,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryFigures.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6827215/v1/f8a55a773723ad2f394f44f9.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"First Reported Implementation of Lenalidomide as Maintenance Therapy for Metastatic Follicular Dendritic Cell Sarcoma","fulltext":[{"header":"Introduction","content":"\u003cp\u003eFDCS is a rare type of neoplasm that arises from follicular dendritic cells, which are critical components of the immune system responsible for presenting antigens to B cells within lymph nodes\u003csup\u003e1\u003c/sup\u003e. FDCS accounts for less than 0.4% of all soft tissue sarcomas, and its presentation varies widely depending on the affected site\u003csup\u003e2\u003c/sup\u003e. While most cases occur in lymph nodes, extranodal FDCS has been reported in the liver, pancreas, tonsils, and other organs\u003csup\u003e3\u003c/sup\u003e. Immunohistochemistry is essential for diagnoses, with CD21, D2-40, CD23, and CD35 recognized as key follicular dendritic cell markers\u003csup\u003e4 5\u003c/sup\u003e, and additional markers such as fascin, clusterin, and podoplanin that may further support diagnosis\u003csup\u003e6\u003c/sup\u003e. Although these markers aid in identification, diagnosis remains challenging due to the tumor\u0026rsquo;s rarity, variable morphology, and lack of distinct clinical features.\u003c/p\u003e \u003cp\u003eAt the present, the primary approach for treating localized FDCS is surgical resection, representing approximately 85% of all cases, but there is not defined standard of care for metastatic FDCS \u003csup\u003e7\u003c/sup\u003e. However, FDCS recurrence remains common, with pooled analysis showing local recurrence in 28.1% and distant metastasis in 27.2% of patients following initial treatment\u003csup\u003e8\u003c/sup\u003e. For advanced FDCS, various chemotherapy regimens, such as CHOP (cyclophosphamide, doxorubicin, oncovin, and prednisone), gemcitabine, and ifosfamide amongst others have been employed, yet they generally offer only transient disease control and limited success in remission\u003csup\u003e6\u003c/sup\u003e. While some data suggests that radiation therapy (RT) may reduce locoregional recurrence rates, this does not consistently translate into improved disease outcomes. For example, in head and neck FDCS, patients receiving surgery plus RT had lower locoregional recurrence rates (15% for both vs. 45% for surgery) compared to surgery alone; however, there was no significant difference in disease free survival, time to first recurrence, death rate, and 5 year overall survival\u003csup\u003e9\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eHere we present the first documented case of using Lenalidomide as a maintenance therapy in metastatic FDCS. Lenalidomide is an immunomodulatory drug widely used in the treatment of multiple myeloma and certain lymphomas\u003csup\u003e10 11\u003c/sup\u003e. It has several mechanisms of action, including promoting T cell activation, enhancing natural killer (NK) cell activity, and inhibiting angiogenesis\u003csup\u003e12\u003c/sup\u003e. This patient\u0026rsquo;s sustained response to lenalidomide, with only a single recurrence over a nearly 6 year timespan, suggests that it offers therapeutic benefit as a maintenance strategy in FDCS, particularly when conventional treatments fail to prevent relapse.\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eThe patient is a 54-year-old female with past medical history including right breast ductal carcinoma in situ, for which she underwent a right mastectomy and prophylactic left mastectomy with bilateral breast reconstruction in 2011. She was initially referred in June 2015 after a chest X-ray revealed a mass in the left perihilar region. CT and PET scans confirmed a 5 cm, intensely PET-avid left hilar mass, with no evidence of distant disease (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA). The patient underwent a left pneumonectomy in which a large tumor was resected, with clear surgical margins and no involvement of hilar lymph nodes (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB), and final pathology identified her tumor as a high-grade FDCS.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe tumor cells demonstrated strong immunohistochemical positivity for CD21, CD23, and CD35 and were negative for keratin and other lineage-specific markers (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC). Additionally, focal expression of D2-40 and TTF-1 was noted, both of which have been previously documented in FDCS\u003csup\u003e13 14\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD). Interestingly, the tumor also showed focal aberrant expression of synaptophysin, a neuroendocrine marker not typically associated with FDCS, which may reflect aberrant differentiation and further underscores the tumor\u0026rsquo;s high-grade, pleomorphic nature (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD). The presence of high-grade features, such as significant cytologic atypia, extensive necrosis, and a high proliferative index indicated a potentially aggressive clinical course (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA). After consultation with sarcoma experts at USC and Cedars-Sinai, adjuvant CHOP chemotherapy was initiated after the left pneumonectomy.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eHowever, following her initial cycle of CHOP chemotherapy in early 2016, the patient developed severe side effects, including significant nausea, vomiting, and bone pain. Despite adjustments to antiemetic therapy, she decided to discontinue CHOP after two cycles due to persistent side effects. Follow-up CT scans showed no further evidence of disease progression, and she was transitioned to regular surveillance.\u003c/p\u003e \u003cp\u003eIn 2017, the patient experienced abdominal pain and bloating. An April PET scan identified a 2.2 cm pelvic mass, and biopsy confirmed FDCS (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). In November of the same year, she underwent an exploratory laparotomy, which included tumor debulking, a left salpingo-oophorectomy, partial omentectomy, and rectosigmoid resection with low anterior anastomosis. Intraoperatively, multiple tumor nodules were found in the left ovary, fallopian tube, rectal serosa, bladder wall, and sigmoid mesentery. Pathology confirmed metastatic FDCS, and clear margins were achieved in most resected tissues, though the disease was extensive. Postoperatively, the patient received six cycles of paclitaxel and gemcitabine chemotherapy, achieving initial disease stabilization. Due to failure of previous chemotherapy regimens, the patient was started on 20 mg Lenalidomide 4 months after paclitaxel and gemcitabine treatment. This initial regimen led to significant gastrointestinal side effects, prompting a dose reduction to 10 mg daily, which she tolerated well.\u003c/p\u003e \u003cp\u003eBy 2019, imaging indicated stable disease with no new metastases. A PET scan at the end of the year showed minimal residual metabolic activity. The patient continued on 10 mg of Lenalidomide daily, showing no indication of new metastases through 2020, 2021, and 2022, as confirmed by regular CT and PET scans. In late 2022, a PET scan revealed a moderately to intensely active heterogeneous mass in the splenic hilum, which appeared larger and more active compared to prior imaging, raising strong suspicion of a neoplastic lesion (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eC). In January 2023, the patient underwent surgery, which included the excision of the recurrent tumor, an in-continuity distal pancreatectomy and splenectomy, and a partial omentectomy. Pathology confirmed the mass as metastatic FDCS. Following recovery, the patient resumed Revlimid at 10 mg daily, with ongoing regular monitoring showing stable disease and no new activity.\u003c/p\u003e \u003cp\u003eThrough late 2023 and 2024, PET scans showed no new areas of increased metabolic activity, and there was no reported disease relapse (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eD). A chronological overview of the patient\u0026rsquo;s clinical course, including diagnosis, recurrences, surgical procedures, systemic therapies, and the achievement of disease-free status is given in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Continuous monitoring with Natera's circulating tumor DNA (ctDNA) testing shows stable ctDNA levels, with no notable increases since early 2023 (Supplemental Fig.\u0026nbsp;1).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThroughout her follow-up visits, the patient has generally reported a good quality of life, managing mild hot flashes and occasional bone pain with over-the-counter medications. She remains physically active, able to exercise regularly without major limitations.\u003c/p\u003e "},{"header":"Discussion","content":"\u003cp\u003eThere has been limited exploration into the role of maintenance therapy in FDCS. A recent report described two patients with bulky abdominopelvic FDCS who were treated with a chemoimmunotherapy regimen combining gemcitabine and docetaxel with pembrolizumab\u003csup\u003e15\u003c/sup\u003e. One patient, who achieved a complete metabolic response after six cycles, continued on the same regimen as maintenance therapy. The other patient, who had hepatic metastases, transitioned to pembrolizumab (PD-1 inhibitor) maintenance following initial therapy and demonstrated tumor shrinkage and symptom improvement. Both patients exhibited intermediate PD-L1 expression and sustained clinical responses with good tolerability. In another instance, the use of just pembrolizumab led to complete remission and a progression-free survival of 24 months in a patient with metastatic tonsillar FDCS following chemoradiotherapy\u003csup\u003e16\u003c/sup\u003e. These cases suggest that immunomodulatory treatment has been successful when applied towards FDCS.\u003c/p\u003e \u003cp\u003eConsidering previous immunotherapy in preventing FDCS spread and recurrence, lenalidomide represents a compelling candidate given its immunomodulatory properties and previously established role in hematologic malignancies\u003csup\u003e17\u003c/sup\u003e. Lenalidomide has become a cornerstone of maintenance therapy in newly diagnosed multiple myeloma (NDMM) following autologous hematopoietic stem cell transplantation (auto-HSCT)\u003csup\u003e18 19\u003c/sup\u003e. Multiple randomized clinical trials, like CALGB 100104, IFM 2005-02, and GIMEMA RV-MM-PI-209, have demonstrated significant progression free survival with hazard ratios of 0.38 and 0.53 in the CALGB and IFM trials, respectively, compared to placebo or no maintenance therapy\u003csup\u003e20\u003c/sup\u003e. A comprehensive patient-level meta-analysis of three randomized controlled trials demonstrated that lenalidomide maintenance therapy following auto-HSCT in newly diagnosed multiple myeloma not only significantly prolonged progression-free survival but also conferred a clinically meaningful overall survival benefit, reducing the risk of death by 25% compared to placebo or observation, with a favorable trend also observed in earlier analyses\u003csup\u003e21\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eWhile these data show lenalidomide as an important maintenance therapy considering multiple myeloma, the mechanistic rationale for using lenalidomide in FDCS is supported by parallels with follicular lymphoma (FL). Lenalidomide, particularly when combined with rituximab, has significantly improved progression-free survival (PFS) in relapsed or refractory FL, even in rituximab-refractory disease\u003csup\u003e22\u003c/sup\u003e. In the RELEVANCE trial, a combined regimen of rituximab and lenalidomide demonstrated comparable efficacy to rituximab plus chemotherapy in previously untreated FL, with a 3-year PFS rate of 77% and fewer grade 3\u0026ndash;4 hematologic toxicities such as neutropenia\u003csup\u003e23\u003c/sup\u003e. Given the overlapping histologic and immunophenotypic features between FDCS and FL, both of which can present as nodular proliferations with spindle or atypical large cells and may express dendritic or lymphoid markers such as CD21, CD35, and S-100, therapies effective in FL may reasonably be considered in FDCS, especially in relapsed or refractory settings\u003csup\u003e24 25 26\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eLenalidomide offers a sound and potentially well-tolerated therapeutic alternative for patients with FDCS, especially when standard chemotherapy is inadequate or contraindicated. In the case presented here, the use of lenalidomide led to long-term disease stabilization extending through 6 years with one recurrence, suggesting that this immunomodulatory therapy may offer durable control in FDCS. As conventional treatment options remain limited and long-term toxicities of chemotherapy are a concern, the introduction of Lenalidomide as a maintenance therapy may represent a paradigm shift in the management of this rare malignancy.\u003c/p\u003e "},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003cdiv id=\"Sec4\" class=\"Section3\"\u003e \u003ch2\u003eCase Report\u003c/h2\u003e \u003cp\u003eThis case report presents a patient diagnosed and treated for follicular dendritic cell sarcoma (FDCS) at Cedars-Sinai Medical Center, Los Angeles, CA. The patient provided written informed consent for use of anonymized clinical data and imaging for publication. Clinical data were retrospectively collected through comprehensive chart review and included pathology, surgical history, imaging, treatment regimens, laboratory results, and follow-up outcomes.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e\n\u003ch3\u003eHistopathology and Immunohistochemistry\u003c/h3\u003e\n\u003cp\u003eDiagnostic confirmation of FDCS was performed through histopathological evaluation and immunohistochemistry (IHC). Surgical specimens, including pneumonectomy and metastatic tissues, were formalin-fixed and paraffin-embedded (FFPE). Tissue sections (approximately 4 \u0026micro;m thick) were stained with hematoxylin and eosin (H\u0026amp;E) for morphological evaluation. Immunohistochemical staining was conducted using automated platforms at Cedars-Sinai Medical Center, with standard antigen retrieval protocols utilizing heat-induced epitope retrieval (HIER) techniques. The presence of FDCS was verified by diffuse positive staining for follicular dendritic markers (CD21, CD23, CD35), focal positivity for TTF-1 and D2-40, and absence of staining for epithelial (pancytokeratin) and lineage-specific markers (CD3, CD20, CD45, Desmin, S100, Napsin A, PAX-8, among others). Appropriate positive and negative controls were included to ensure the accuracy of staining results.\u003c/p\u003e\n\u003ch3\u003eImaging and Disease Monitoring\u003c/h3\u003e\n\u003cp\u003eLongitudinal disease monitoring was conducted via serial 18F-FDG PET/CT and CT scans from 2015 through 2025. Imaging data was collected and reviewed by board-certified radiologists at Cedars-Sinai Medical Center. Imaging studies assessed both metabolic activity and anatomical changes across thoracic, abdominal, and pelvic regions. Circulating tumor DNA (ctDNA) testing (Signatera\u0026trade;, Natera Inc.) was incorporated as a non-invasive method to track minimal residual disease and treatment response from 2023 onward.\u003c/p\u003e\n\u003ch3\u003eData Availability\u003c/h3\u003e\n\u003cp\u003eThe study data will be made available upon request to the corresponding author.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor Contributions Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eK.K.S. provided clinical care and treatment for the patient. K.K.S. and S.K. conceptualized the study. S.K. and E.S. were responsible for data collection and S.K. was responsible for all figure (Fig 1-3 and Supplemental Figure) creation. Manuscript writing was conducted by S.K., E.S., I.H., S.L., A.I., J.H., M.B., M.L., and B.H. All authors reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding Declaration\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;We do not have external funding for this research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics Statement and Consent to Publish Declaration\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;The patient provided written informed consent for the use of anonymized clinical data and imaging for publication. Clinical trial number: not applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eKairouz, S., Hashash, J., Kabbara, W., McHayleh, W. \u0026amp; Tabbara, I.A. 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Follicular lymphomas and histiocytic/dendritic neoplasms related? \u003cem\u003eBlood\u003c/em\u003e\u003cstrong\u003e111\u003c/strong\u003e, 5418\u0026ndash;5419 (2008).\u003c/li\u003e\n\u003cli\u003eKurshumliu, F., \u003cem\u003eet al.\u003c/em\u003e Divergent immunohistochemical expression of CD21 and CD23 by follicular dendritic cells with increasing grade of follicular lymphoma. \u003cem\u003eWorld Journal of Surgical Oncology\u003c/em\u003e\u003cstrong\u003e17\u003c/strong\u003e(2019).\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":"","lastPublishedDoi":"10.21203/rs.3.rs-6827215/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6827215/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eFollicular dendritic cell sarcoma (FDCS) is an exceptionally rare, low- to intermediate-grade malignancy arising from mesenchymal-derived follicular dendritic cells, but can present with high-grade pathological features and may rapidly become fatal. Conventional therapeutic strategies, primarily consisting of surgical resection with adjunctive systemic chemotherapy, such as gemcitabine-docetaxel, ifosfamide, doxorubicin, or other regimens, remain inconsistently effective, with median survival notably reduced in advanced or recurrent disease. Given the limited therapeutic options and frequent relapse, there is a critical need for well-tolerated treatments that can improve long term outcomes for patients with metastatic FDCS. Here, we report the first documented clinical use of the immunomodulatory agent Lenalidomide (Revlimid) as maintenance therapy following chemotherapy. Remarkably, the patient achieved nearly total sustained remission with exceptional disease stabilization for approximately six years, experiencing only one manageable recurrence. This clinical response points to lenalidomide as a promising maintenance therapy for metastatic FDCS and may provide further basis for consideration of lenalidomide as a potential first line treatment.\u003c/p\u003e","manuscriptTitle":"First Reported Implementation of Lenalidomide as Maintenance Therapy for Metastatic Follicular Dendritic Cell Sarcoma","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-04 05:33:33","doi":"10.21203/rs.3.rs-6827215/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":"fb3647a1-5088-4921-9590-729436ac5eb8","owner":[],"postedDate":"July 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-24T13:39:15+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-04 05:33:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6827215","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6827215","identity":"rs-6827215","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}