title: Clinicopathologic characteristics of inflammatory pseudotumor-like follicular dendritic cell sarcoma.
abstract: Inflammatory pseudotumor (IPT)-like follicular dendritic cell (FDC) sarcoma is a recently described rare tumor and considered a unique entity, with different histologic appearances and behavior from those of the classical FDC sarcoma. This study analyzed the clinical and pathological findings of two such cases that the authors encountered and 36 previously reported cases identified in the literature. Assessment of all 38 cases showed a slight female predominance (2.2:1) with a median age of 56.5 years. Seventeen patients complained of abdominal discomfort or pain, while fifteen patients had no clinical symptom. Almost all cases occurred in liver (n=20) or spleen (n=17). Except in one case, all patients underwent surgical resection of the tumor alone. Histologic features showed a mixture of chronic inflammatory cells and variable amounts of spindle cells with vesicular nuclei and distinct nucleoli. The tumor cells expressed conventional FDC markers such as CD21 (75%), CD35 (92%), CD23 (62%), clusterin (75%), and CNA.42 (100%). EBV was detected in thirty-five cases (92.1%) by Epstein-Barr virus (EBV)-encoded RNA in situ hybridization, and EBV-latent membrane protein-1 was expressed in 90% of the cases. With a median follow-up of 21 months, 29 patients (85.3%) were alive and well, 4 (11.8%) were alive with disease, one patient (2.9%) died of disease. Only four patients with hepatic tumors underwent recurrence or metastasis after initial treatment. Epstein-Barr virus is thought to play a role in the development of the tumor; however, the pathogenesis of the disease and the origin of tumor cells remain unclear.
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Rong
authors: R
authors: Ge
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Chuangfeng
authors: C
authors: Liu
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Xiangang
authors: X
authors: Yin
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Jinping
authors: J
authors: Chen
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Xincheng
authors: X
authors: Zhou
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Chunxin
authors: C
authors: Huang
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Wenying
authors: W
authors: Yu
authors: Department of Diagnosis, Ningbo Diagnostic Pathology Center Ningbo 315021, China.
authors: Xiaohan
authors: X
authors: Shen
mesh_terms: D015746:Abdominal Pain / Q000209:etiology; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D004279:DNA, Viral / Q000235:genetics; D054740:Dendritic Cell Sarcoma, Follicular / Q000150:complications / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000601:surgery / Q000821:virology; D020566:Dendritic Cells, Follicular / Q000737:chemistry / Q000473:pathology* / Q000821:virology; D005260:Female; D006104:Granuloma, Plasma Cell / Q000150:complications / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000601:surgery / Q000821:virology; D006498:Hepatectomy; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008113:Liver Neoplasms / Q000737:chemistry / Q000150:complications / Q000401:mortality / Q000473:pathology* / Q000601:surgery / Q000821:virology; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D011237:Predictive Value of Tests; D012307:Risk Factors; D013156:Splenectomy; D013160:Splenic Neoplasms / Q000737:chemistry / Q000150:complications / Q000401:mortality / Q000473:pathology* / Q000601:surgery / Q000821:virology; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D004279:DNA, Viral
keywords: Epstein-Barr virus; Follicular dendritic cell sarcoma; inflammatory pseudotumor; liver; spleen