Favorable response to PD-1 inhibitor plus chemotherapy as first-line treatment for metastatic follicular dendritic cell sarcoma of the spleen: a case report.

Follicular dendritic cell sarcoma (FDCS) is an uncommon low-grade malignant sarcoma. For localized FDCS, surgery is the most commonly recommended therapy option. However, there is no standard treatment protocol for metastatic FDCS. Here, we present a 68-year-old female with primary spleen FDCS who had multiple peritoneal metastases. She was treated with sintilimab (PD-1 inhibitor) plus chemotherapy (epirubicin plus ifosfamide) as first-line treatment achieving partial response (PR) and a relatively long progression-free survival (PFS) of 17 months. This case suggests that PD-1 inhibitor plus chemotherapy as first-line therapy seem to be a promising treatment option for metastatic FDCS.

18 F-FDG PET/CT in Extensive Follicular Dendritic Cell Sarcoma With Response Assessment to Chemotherapy.

ABSTRACT: Follicular dendritic cell sarcoma (FDCS) is a low-grade sarcoma of mesenchymal dendritic cell origin, and it constitutes <0.4% of soft tissue sarcomas. We report a rare case of FDCS in a 32-year-old man. 18 F-FDG PET/CT demonstrated the involvement of cervical, axillary, mediastinal, abdominal, and pelvic groups of lymph nodes and spleen. A cervical lymph node biopsy suggested FDCS. 18 F-FDG PET/CT scan done after 3 cycles of chemotherapy (CHOP regime) revealed a complete metabolic response. This case presents the rarity of extensive presentation and complete response to the CHOP regime.

Unexpected Favorable Outcome to PD-1 Antibody Plus Lenvatinib in a Patient With Recurrent Intestinal Follicular Dendritic Cell Sarcoma: A Case Report and Literature Review.

Background: Follicular dendritic cell sarcoma (FDCS) is an uncommon malignant cancer, and there is no standard treatment to date. Resection followed by adjuvant chemotherapy or radiation is considered the most commonly used strategy for treatment. However, the treatment for patients who have progressed after systemic treatment is more controversial. Case summary: In this case report, we describe a 57-year-old man with primary small intestine FDCS where surgery and second-line systemic chemotherapy failed. After disease progression (PD), the patient received sintilimab plus lenvatinib as third-line treatment and achieved a progression-free survival (PFS) with 7 months. Conclusion: This is the first report of a FDCS patient treated with immune checkpoint inhibitors (ICIs) and antiangiogenic agents, sintilimab and lenvatinib, as third-line therapy. Our case provides a potential therapeutic option for patients with FDCS who progressed after multiline therapy.

Follicular dendritic cell sarcoma of the uterine cervix: a case report.

BACKGROUND: Follicular dendritic cell sarcoma (FDCS) is a rare mesenchymal tumor that mostly occurs in systemic lymph nodes. FDCS in the uterine cervix has not yet been reported. CASE PRESENTATION: A 49-year-old woman was referred to our department with a cervical tumor, which was histologically suspected to be undifferentiated carcinoma. She underwent hysterectomy, salpingo-oophorectomy, and pelvic lymphadenectomy after neoadjuvant chemotherapy with paclitaxel and carboplatin. The resected specimen contained high numbers of spindle cells and was immunohistochemically confirmed to be FDCS. The tumor was completely resected and recurrence was not detected at a 16-month follow-up. CONCLUSION: FDCS is an extremely rare malignant tumor in the uterine cervix, and an accurate diagnosis and complete resection are essential for a good prognosis.

Follicular dendritic cell sarcoma and its response to immune checkpoint inhibitors nivolumab and ipilimumab.

Follicular dendritic cell sarcoma (FDCS) is a rare and unusual cancer that arises from sustentacular cells of the lymph node that present antigen to B cells, rather than lymphocytes themselves. While surgery for primary disease is still paramount in primary management, for unresectable, recurrent and metastatic tumours, FDCS is frequently treated with anthracycline-based lymphoma chemotherapy regimens. In recent years, it is clear that Programmed Cell Death 1 (PD1)-directed immune checkpoint inhibitors (ICIs) are active in Hodgkin lymphoma, but significantly less active in non-Hodgkin's lymphoma. These data raised the question of whether FDCS respond to ICI therapy. We present two patients with FDCS who were treated with nivolumab and ipilimumab with evidence of tumour response. These cases also highlight the difficulty in arriving at a proper diagnosis, emphasising the need for expert review of pathology to optimise treatment for these and other patients with sarcoma.

Temozolomide targets and arrests a doxorubicin-resistant follicular dendritic-cell sarcoma patient-derived orthotopic xenograft mouse model.

Follicular dendritic cell sarcoma (FDCS) is a very rare and highly recalcitrant disease. A patient's doxorubicin-resistant FDCS was previously established orthotopically on the right high thigh into the biceps femoris of mice to establish a patient-derived orthotopic xenograft (PDOX) model. The aim of the present manuscript was to identify an effective drug for this recalcitrant tumor. Here, we evaluated the efficacy of temozolomide (TMZ), trabectedin (TRAB) and pazopanib (PAZ) on the FDCS PDOX model. PDOX mouse models were randomized into five groups of eight to nine mice, respectively. Group 1, untreated control with PBS, i.p.; Group 2, treated with doxorubicin (DOX), 2.4 mg/kg, i.p., weekly for 3 weeks; Group 3, treated with PAZ, 50 mg/kg, oral gavage, daily for 3 weeks; Group 4, treated with TMZ, 25 mg/kg, oral gavage, daily for 3 weeks; Group 5, treated with TRAB, 0.15 mg/kg, i.v., weekly for 3 weeks. Body weight and tumor volume were assessed 2 times per week. TMZ arrested the FDCS PDOX model compared to the control group (p < 0.05). PAZ and TRAB did not have significant efficacy compared to the control group (p = 0.99, p = 0.69 respectively). The PDOX tumor was resistant to DOX (p= 0.99). as was the patient. The present study demonstrates that TMZ is effective for a PDOX model of FDCS established from a patient who failed DOX treatment, further demonstrating the power of PDOX to identify effective therapy including for tumors that failed first line therapy.

Small intestine follicular dendritic cell sarcoma with liver metastasis: A case report.

RATIONALE: Follicular dendritic cell sarcoma (FDCS) is a rare neoplasia composed of spindle or oval cells with follicular dendritic cell differentiation, usually occurring in lymphoid tissue. In this report, we present a case of FDCS of the small intestine with liver metastasis. PATIENT CONCERNS: A 19-year-old female presented with recent onset of left upper abdominal pain. Abdominal computed tomography scan showed a large tumor mass in the liver lateral segment with compression to the pancreas upper part, and a smaller mass in the terminal ileum, respectively. High serum levels of amylase and lipase were noted. Resection of the tumors was performed. Microscopically, both tumors consisted of ovoid to spindle-shaped nuclei cells admixed with some lymphocytes arranged in fascicles, whorls, storiform arrays. Immunohistochemistry demonstrated that the tumor cells were positive for follicular dendritic cell markers, including CD21, CD23, and CD35. Epstein-Barr virus encoding small RNA (EBER; Inform EBER probe; Ventana Medical Systems, Tucson, AZ) in situ hybridization was negative. DIAGNOSES: According to the clinicopathological features, diagnosis of FDCS of intestinal origin was made. INTERVENTIONS: Resection of tumors located in the liver and at the small intestine was performed. After the operation, patient received adjuvant vinblastin chemotherapy. OUTCOMES: There was no evidence of recurrence at 8-month follow-up. LESSONS: It was unusual for FDCS of intestinal origin with liver metastasis and expressing with high serum levels of pancreatic enzymes.

Follicular dendritic sarcoma masquerading as fibrosing mediastinitis.

Fibrosing mediastinitis (FM) is a rare disorder resulting from abnormal immunological-mediated fibro-proliferative reaction in the mediastinum. Here, we describe a case of a 46-year-old female with an incidentally found 11×9 cm posterior mediastinal mass. Multiple biopsies of this unresectable, 18-fluorodeoxyglucose avid mass revealed marked fibrosis without any evidence of malignancy, suggesting idiopathic fibrosing mediastinitis as our initial diagnosis. Multiple interventions including a trial of steroids, fluconazole, and azathioprine to target fibrosing mediastinitis were not successful. Repeat biopsy was consistent with primary mediastinal follicular dendritic cell sarcoma. The manuscript highlights the heightened need for suspecting occult malignancies in cases of FM presenting with an indeterminate cause.

Follicular dendritic cell sarcoma treated with a variety of chemotherapy.

Follicular dendritic cell sarcoma (FDCS) is a very rare malignant tumor derived from follicular dendritic cells. Radical resection is the standard therapy for patients with local disease, but an optimal chemotherapy regimen has not been determined for unresectable disease. We report our experience of an FDCS patient with multiorgan involvement. In the present case, disease was only located in the pancreas initially and radical resection was performed. Multiple metastasis developed after the treatment and several factors that indicated a poor prognosis were observed. The present case had a very poor prognostic disease but survived for a long time with a good performance status because of the multiple chemotherapy regimens, which follow therapeutic strategies for malignant lymphoma and soft tissue sarcoma. As far as we know, this is the first study reporting the indication of bendamustine for FDCS patients.

Treatment of breast cancer 2 (BRCA2)-mutant follicular dendritic cell sarcoma with a poly ADP-ribose polymerase (PARP) inhibitor: a case report.

BACKGROUND: Follicular dendritic cell sarcoma is a rare tumour with clinical behaviour covering a spectrum from indolent to aggressive disease. Treatment recommendations are currently based on case reports and small series describing combinations of surgery, chemotherapy and radiotherapy providing the best patient outcomes. Recent knowledge on molecular aberrations in this disease have not yet impacted on therapeutic decisions. CASE PRESENTATION: We describe a case of progressive follicular dendritic cell sarcoma of the lung and pleura, treated based on knowledge of the tumour's molecular aberrations. The patient was initially treated with surgery, chemotherapy and radiotherapy and developed disease progression. Mutation testing by Caris molecular intelligence demonstrated a breast cancer 2 gene mutation and further treatment with carboplatin and veliparib achieved disease stabilisation. CONCLUSION: Understanding of the molecular profile of rare tumours is key to improve therapeutic decision making and patient outcomes.

High efficacy of tumor-targeting Salmonella typhimurium A1-R on a doxorubicin- and dactolisib-resistant follicular dendritic-cell sarcoma in a patient-derived orthotopic xenograft PDOX nude mouse model.

Follicular dendritic-cell sarcoma (FDCS) is a rare and recalcitrant disease. In the present study, a patient-derived orthotopic xenograft (PDOX) mouse model of FDCS was established in the biceps muscle of nude mice. The FDCS PDOX was resistant to both doxorubicin (DOX) and NVP-BEZ235, dactolisib (BEZ) an experimental agent which is a dual pan-phosphoinositide 3-kinase-mammalian target of rapamycin inhibitor. However, in contrast to DOX and BEZ, the FDCS PDOX was sensitive to the tumor-targeting bacterial strain, Salmonella typhimurium A1-R (S. typhimurium A1-R). The combination of S. typhimurium A1-R and either DOX or BEZ did not increase the antitumor efficacy of S. typhimurium A1-R, indicating that DOX and BEZ were not active in this PDOX model. The efficacy of S. typhimurium A1-R in this recalcitrant FDCS gives strong impetus to move bacterial therapy to clinical trials for this disease. The findings of the present study are of particular importance since it demonstrates that S. typhimurium A1-R is effective in a PDOX model of FDCS established from a patient who failed DOX therapy.

Follicular dendritic cell sarcoma of the tonsil.

Follicular dendritic cell sarcoma (FDCS) is an uncommon tumour within the spectrum of histiocytic and dendritic cell neoplasms that can occur at nodal and extra-nodal sites. Besides being rare, these tumours are difficult to diagnose. A 72-year-old man with a painless mass in the right tonsil was admitted to the Mersin University Hospital. Tonsillectomy was performed. Microscopically, the tumour consisted of spindle-shaped cells with large oval to polygonal nuclei. Lymphocytes were scattered among the tumour cells. Immunohistochemically, the cells were positive for CD23 and vimentin. The tumour was diagnosed as FDCS with histological and immunohistochemical findings. Recognition of extranodal FDCS requires knowledge of this entity and to consider it during the diagnosis. Confirmatory immunohistochemical staining is essential for diagnosis. Correct characterisation of this neoplasm is important because of its potential for recurrence and metastasis.

Follicular dendritic cell sarcoma of the neck: report of a case treated by surgical excision and COP plus (PEG)-liposomal doxorubicin.

BACKGROUND: Follicular dendritic cell (FDC) sarcoma is a rare neoplasm arising in lymph nodes but also in extranodal sites from accessory cells of the immune system that are essential for the function of antigen presentation and germinal center reaction regulation. FDC sarcoma has a significant recurrent and metastatic potential and for these reason it should be viewed as an intermediate grade malignancy. METHODS: We report the case of a 49-year old woman patient who showed persistent, enlarged, hard, cervical lymph node. The most common histologic feature was the presence of oval to spindle cells with elongated nuclei, vesicular or stippled chromatin and scant eosinophilic cytoplasm. Immunohistochemically, tumor cells were diffusely positive for follicular dendritic cell markers CD21, CD23 and negative for cytokeratin.The patient after complete excision of the lymph node underwent five courses of adjuvant chemotherapy with COP plus PEG-liposomal doxorubicin, considering the propensity of the tumor to metastasize. RESULTS: No hematological or cardiac toxicity were registered and among the other extra hematological effects only transitory palmar erythrodysesthesia is worthy of mention. After a follow up of 5 years the patient is alive and in CR. CONCLUSION: These results suggest that this therapeutic modality may be useful in the management of FDC sarcoma.