EBER-negative inflammatory pseudotumor-like follicular dendritic cell sarcoma of liver: A case report.

RATIONALE: Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) of the liver is rare. It was previously believed that Epstein-Barr virus (EBV) positivity was a necessary criterion for pathological diagnosis. However, we found that there were also cases of EBV negativity. Therefore, clinicians and pathologists are reminded that EBV positivity is not a necessary condition for diagnosis. PATIENT CONCERNS: A 70-year-old female underwent computed tomography (CT) examination for upper abdominal discomfort, which revealed the presence of a liver tumor. Follow-up revealed that the tumor had progressively increased in size. DIAGNOSIS: The final diagnosis was an IPT-like follicular cell sarcoma, based on CT, MRI, HE staining, and immunohistochemical staining. INTERVENTIONS: The patient underwent a laparoscopic left hemihepatectomy. OUTCOMES: The patient has not undergone any special treatment, such as radiotherapy and chemotherapy, and has been followed up for over 3 years without experiencing any recurrence. LESSONS: IPT-like FDCS is a rare tumor that lacks definitive criteria, and its diagnosis mainly relies on pathological findings. Previously, it was believed that being EBV-positive was an important condition for diagnosis. Primary IPT-like FDCS in the liver is even rarer, and the patient in this case tested negative for EBV. It may be necessary for pathologists to consider the role of EBV in the diagnosis of IPT-like FDCS.

Extranodal follicular dendritic cell sarcoma of the tonsil: An extremely rare clinical entity.

Follicular dentritic cell sarcomatous neoplasms originate from dendritic cells contained within the lymph nodes. In extranodal location, these neoplasms, are rare clinical entities, and even more so, their location in the head-neck region is extremely rare. Only 17 cases of primary dendritic cell sarcoma of the tonsil are reported in the literature at present. Being such a rare entity, histopathological diagnosis can be complex and requires great expertise and proper immunohistochemical analysis [1]. We present a case of a 48-year-old young man diagnosed with follicular dendritic cell sarcoma of the tonsil who underwent, probably for the first time in the literature, transoral robotic surgical resection.

Pancreatic follicular dendritic cell sarcoma: a case report.

BACKGROUND: Follicular dendritic cell sarcoma (FDCS) is a rare, low-to-moderate-grade malignant tumor, which occurs in the dendritic cells of the germinal center. Pancreatic FDCS (PFDCS) is extremely rare, with only a few reported cases. Presently, the etiology and pathogenesis of pancreatic FDCS are still unclear, and the clinical symptoms and signs as well as the laboratory diagnosis lack specificity. Although PFDCS presents better histological and morphological characteristics and a distinct immunophenotype, it can be easily missed and/or misdiagnosed if it occurs outside the node. Lymph node FDCS are easier to diagnose because of the rarity of fusiform cell tumors in lymph nodes. CASE DEMONSTRATION: Herein, we reported a 67-year-old female patient with upper-left abdominal pain without obvious cause and was admitted for treatment. A computed tomography (CT) scan revealed a cystic solid mass in the pancreatic tail toward the greater curvature of the stomach, with an obvious enhancement of the cyst wall in enhanced scanning. Subsequently, the patient underwent surgical resection and the resected sample was sent for pathological biopsy. According to the results, the pathology was consistent with the histological morphology and immunohistochemical characteristics of FDCS, and the Epstein-Barr virus (EBV)-encoded RNA was negative for in situ hybridization. Three months post-resection, the patient returned to the hospital for chemotherapy. This case report is aimed to improve the clinical recognition of FDCS. CONCLUSION: Pancreatic FDCS is a rare disease. Herein, we have reported a case of pancreatic FDCS and analyzed its clinical and pathological features and differential diagnosis to improve the understanding of FDCS.

Follicular dendritic cell sarcoma arising in the stomach and abdominal cavity: A case report.

RATIONALE: Follicular dendritic cell sarcoma (FDCS) is a rare mesenchymal tumor that typically develops in lymph nodes; it is clinically uncommon and has only occasionally been documented in cases of soft tissue, liver and spleen, and retroperitoneum; it is also extremely uncommon to develop in the stomach. PATIENT CONCERNS: A 64-year-old woman who discovered a lump in her left upper abdomen 6 months prior and was taken to the hospital due to excruciating abdominal pain. DIAGNOSIS: An abdominal computed tomography scan showed a soft tissue mass around the cardia. The immunohistochemical and postoperative histopathology results were compatible with FDCS. INTERVENTIONS: The patient underwent "radical total gastrectomy and esophagojejunostomy" (Roux-Y anastomosis). OUTCOMES: The patient recovered well 2 months after surgery. LESSONS: We report a case of FDCS occurring in the stomach and abdominal cavity, which was unique in terms of clinical location, clinical presentation, and imaging signs. This case report aims to enhance clinicians' understanding and diagnosis of FDCS in the stomach and abdominal cavity and reduce the rate of clinical misdiagnosis.

Pancreatic follicular dendritic cell sarcoma: a rare case report and systematic literature review of 7 cases.

INTRODUCTION: Pancreatic follicular dendritic cell sarcoma (FDCS) is an exceptionally rare and low-to-moderate malignancy, with only seven reported cases to date. Clinical diagnosis of FDCS is challenging due to the lack of distinct biological and radiographic features. CASE PRESENTATION: A 67-year-old woman presented to the hospital with a 4-day history of severe abdominal pain. Imaging studies (CT and MRI) revealed a large cystic mass located at the tail of the pancreas, which was suspected to be myeloid sarcoma (MS) based on EUS and CT-guided pancreatic puncture. Postoperative pathology and immunohistochemistry confirmed the diagnosis of pancreatic FDCS. After the diagnosis was confirmed, the patient received postoperative chemotherapy with the CHOP regimen. At 11 months of follow-up, there was no evidence of recurrence. Seven published cases have been reviewed to comprehensively summarize the clinical characteristics, diagnosis, and treatment options of FDCS. CONCLUSION: While imaging can be useful in detecting pancreatic FDCS, it should be interpreted with caution as it can be challenging to differentiate from other pancreatic tumors. Pathology and immunohistochemistry are considered the gold standard for diagnosis, with CD21, CD23, and CD35 being specific tumor cell markers. However, preoperative diagnosis of pancreatic FDCS remains difficult, and the pancreatic puncture may further increase the risk of misdiagnosis. The disease is highly prone to recurrence and metastasis, and surgery is the preferred method for both diagnosis and treatment of localized disease.

Extranodal Follicular Dendritic Cell Sarcoma of the Head and Neck Region: A Clinicopathological Study of 7 Cases.

Background. Follicular dendritic cell (FDC) sarcoma is a rare neoplasm arising from follicular dendritic cells (FDCs). It can be nodal or extranodal. Histological diagnosis of extranodal FDC sarcoma in the head and neck region is challenging and a significant percentage are misdiagnosed. Objectives. To report clinicopathological features of head and neck extranodal FDC sarcoma cases and discuss differential diagnoses. Methods. Seven head and neck extranodal FDC sarcomas were retrieved and clinicopathological features were noted. Results. Two tumors each involved parapharyngeal space and tonsil while remaining cases involved the parotid, soft tissue of neck and oropharynx. Age range was 12 to 79 years (mean and median age were 40 and 44 years respectively) and there was a male predilection (6 males: 1 female). All showed spindle to ovoid cells arranged in fascicles, whorls and/or storiform pattern. Mitoses ranged from 3 to 20/mm2. All tumors expressed CD21 and CD23. Two patients died of their disease at 9 and 16 months. Both had tumors larger than 5 cm with ≥10 mitoses/mm2. Three patients were alive at 12, 44 and 184 months. Conclusions. There was a distinct male predominance in our cohort. FDC sarcoma should be included in the differential diagnosis of spindle cell extranodal neoplasms in the head and neck with a whorled growth pattern and intratumoral lymphocytes. Head and neck region tumors show similar clinicopathologic characteristics as their counterparts at other locations with potential for aggressive behavior especially in tumors greater than 5 cm in size and with high mitotic rates.

Follicular Dendritic Cell Sarcoma of Uterine Corpus: Report of 2 Cases.

Follicular dendritic cell sarcoma is a rare dendritic/histiocytic tumor of intermediate malignant potential, which often involves extranodal sites, most commonly the gastrointestinal tract and mediastinum with only 5 cases reported in the female genital tract. We present the clinical and pathologic features of 2 such examples arising in the uterine corpus. Both patients (63 and 72-yr old) presented with postmenopausal bleeding and underwent an endometrial biopsy diagnostic of follicular dendritic cell sarcoma that was followed by hysterectomy. The tumors were polypoid, 3.5 and 5.0 cm, and were confined to the endometrium. Microscopically, ovoid to round to spindled tumor cells with pale eosinophilic cytoplasm and vesicular nuclei were arranged predominantly in sheets with an accompanying lymphocyte-rich inflammatory infiltrate. The tumor cells were positive for CD35, CD23, D2-40 in both tumors and additionally positive for CD21 in 1 tumor, all highlighting cell bodies and processes. Patients were alive without evidence of disease at 1 and 4 years with no adjuvant treatment. These cases highlight the importance of entertaining a broad differential diagnosis in lesions with epithelioid and/or spindled morphology involving the uterus.

Pancreatic follicular dendritic cell sarcoma: one case report and literature review.

Pancreatic follicular dendritic cell sarcoma (FDCS) is a rare neoplasm with unclear pathological characteristics. In this study, we report one case of pancreatic FDCS and review published cases to summarize the characteristics and treatment of pancreatic FDCS. A man in his early 30 s was admitted for jaundice, abdominal fullness, and weight loss for 15 days. Computed tomography revealed a large capsule solid mass in the pancreatic head together with a dilated bile duct and enlarged retroperitoneal lymph nodes. Serum biochemistry revealed high total bilirubin levels (313.9 µmol/L) and normal tumor marker levels. Pancreatoduodenectomy was performed, but no chemotherapy was administrated at the patient's behest. The pathologic diagnosis was pancreatic FDCS infiltrating the duodenal seromuscular layer and common bile duct. The patient presented with liver metastasis 3 months after surgery and died 8 months after surgery from multiorgan failure. Pancreatic FDCS is a rare disease with high invasiveness. Our previous case exhibited paraneoplastic syndrome together with this disease, and further investigation is needed to confirm whether paraneoplastic syndrome is a typical syndrome of pancreatic FDCS.

Thoracic follicular dendritic cell sarcoma - an outlandish presentation of a rare tumour with review of literature.

Follicular dendritic cell sarcoma is a rare low grade malignant neoplasm that arises from follicular dendritic cells in lymphoid tissue germinal centres and accounts for 0.4% of all soft tissue sarcomas. It is extremely rare to have pulmonary follicular dendritic cell sarcoma with endobronchial extension and as an anterior mediastinal mass with mediastinal lymph node involvement. We present the case of a 34-year-old male non-smoker who had been experiencing chest pain for three months. A lobulated left peri-hilar mass with endobronchial spread into the left main bronchus and mediastinal lymphadenopathy was identified on a chest CT. The bronchoscope-guided cryobiopsy of the endobronchial mass was inconclusive. After a thorough multidisciplinary discussion, the patient underwent left sided pneumonectomy, mediastinal mass resection, and systematic lymph node dissection. Histologic examination using immunohistochemistry revealed follicular dendritic cell sarcoma.

Radiologic and Histopathologic Features of a Neck-Localised Follicular Dendritic Cell Sarcoma: A Case Report and Literature Review.

Follicular dendritic cell sarcoma (FDCS) is an uncommon tumour. The pathological features of FDCS have been extensively described in the literature, but there are few reports on its imaging features. A 48-year-old man presented at our hospital with a mass in the left submandibular region without associated oral complaints. Contrast-enhanced magnetic resonance imaging revealed a mass with smooth margins, and postoperative histopathological and immunohistochemical findings were consistent with FDCS. At present, our understanding of FDCS is still insufficient, and its diagnosis is dependent on pathological evaluation. We aim to provide a bit of information for clinicians to consider when they see these types of tumours. Key Words: Follicular dendritic cell sarcoma, Magnetic resonance imaging, Imaging features, Histopathology.

Follicular dendritic cell sarcoma of the nasopharynx: a case report and literature review.

Follicular dendritic cell sarcoma (FDCS) of the nasopharynx is a rare malignant tumor that has been described in only a few case reports, and its differential diagnoses include diverse clinicopathologic entities. FDCS is often initially misdiagnosed, especially when examining small biopsy specimens. We herein report a case of FDCS arising in the nasopharynx that was initially misdiagnosed as a nerve sheath tumor. A 44-year-old woman presented with persistent obstruction of the left nasal cavity and underwent an excisional biopsy. The specimen demonstrated morphologic and immunohistochemical features of FDCS. In situ hybridization for Epstein-Barr virus-encoded RNA was negative. The patient was treated with chemotherapy and radiotherapy. The sarcoma recurred near the original site more than 3 years after the initial treatment and was completely resected. At the time of this writing, the patient had remained disease-free for 1 year after resection. This case is being reported to improve the clinical recognition of FDCS.

Follicular dendritic cell sarcoma of the thigh: a clinicopathological report and management approach.

Follicular dendritic cells are antigen-presenting immune accessory cells of mesenchymal origin. Follicular dendritic cell sarcomas (FDCS) typically occur in nodal and extranodal sites. However, presentation in the extremity has rarely been reported. A woman in her 60s had a painless, slow-growing right posterior thigh swelling, which had been present for 9 months. Imaging revealed a subcutaneous lesion in the posterior aspect of the right mid-thigh. Fine-needle aspiration cytology from the lesion was suggestive of a malignant spindle cell neoplasm, and she underwent its wide local excision. Immunohistochemistry showed expression of epithelial membrane antigen and CD35, but an absence of cytokeratin, desmin, CD23 and S100. The Ki-67 index was low and a diagnosis of FDCS was made. The lack of clinical guidelines was a challenge in the treatment of this rare case. A multidisciplinary board discussion played a critical role in the planning of the patient's adjuvant treatment.