Intracranial follicular dendritic cell sarcoma. Case report.
ABSTRACT Intracranial occurrence of follicular dendritic cell (FDC) sarcoma, a rare tumor derived from dendritic cells of the lymphoid follicle, has not yet been described. Therefore, the case of a 53-year-old man presenting with an intracranial mass invading the clivus is reported. The diagnosis of FDC sarcoma was confirmed by immunohistochemical staining for dendritic cell markers, that is, CD21, CD23, and CD35. Due to some similarities with meningioma, intracranial FDC sarcoma might be an underdiagnosed disease.
- [show abstract] [hide abstract]
ABSTRACT: Extranodal follicular dendritic cell (FDC) sarcoma of the head and neck region is uncommon, with 16 well-documented cases previously reported (four in the tonsil, four in the pharynx, two in the palate, five in the soft tissue, and one in the thyroid). We here report an additional three cases of extranodal FDC sarcoma in the tonsil (two cases) and pharynx (one case). In these new cases, the neoplastic cells were arranged in diffuse, fascicular, and vaguely whorled growth patterns. A background lymphocytic infiltrate was sprinkled throughout the neoplasms, with focal prominent perivascular cuffing. Scattered multinucleated giant cells were present. Immunohistochemically, tumor cells were strongly and diffusely positive for follicular dendritic cell markers CD21 and CD35. Tumor cells were diffusely positive for fascin and negative for leukocyte common antigen, S-100 protein, cytokeratin, and Epstein-Barr virus (EBV) latent membrane protein-1 (EBV-LMP). EBV was also not detected in the tumor cells by in situ hybridization for EBV-encoded RNAs. FDC sarcomas are probably an underrecognized neoplasm, especially when they occur in extranodal sites in the head and neck region. Two of the three new cases we report were initially misdiagnosed, and five cases of extranodal FDC sarcoma in the head and neck region reported in the recent literature were initially misdiagnosed. Our aim is to complement the current understanding of this neoplasm and alert pathologists to this rare entity in this region to avoid misdiagnosis. Recognition of extranodal FDC sarcoma requires a high index of suspicion, but this tumor has numerous distinctive histological features that should bring the neoplasm into the differential diagnosis. Confirmatory immunohistochemical staining with follicular dendritic cell markers such as CD21 and/or CD35 is essential for the diagnosis. Correct characterization of this neoplasm is imperative given its potential for recurrence and metastasis.Modern Pathology 02/2002; 15(1):50-8. · 5.25 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell neoplasms, the International Lymphoma Study Group (ILSG) stained 61 tumours of suspected histiocytic/dendritic cell type with a panel of 15 antibodies including those reactive with histiocytes (CD68, lysozyme (LYS)), Langerhans cells (CD1a), follicular dendritic cells (FDC: CD21, CD35) and S100 protein. This analysis revealed that 57 cases (93%) fit into four major immunophenotypic groups (one histiocytic and three dendritic cell types) utilizing six markers: CD68, LYS, CD1a, S100, CD21, and CD35. The four (7%) unclassified cases were further classifiable into the above four groups using additional morphological and ultrastructural features. The four groups then included: (i) histiocytic sarcoma (n=18) with the following phenotype: CD68 (100%), LYS (94%), CD1a (0%), S100 (33%), CD21/35 (0%). The median age was 46 years. Presentation was predominantly extranodal (72%) with high mortality (58% dead of disease (DOD)). Three had systemic involvement consistent with 'malignant histiocytosis'; (ii) Langerhans cell tumour (LCT) (n=26) which expressed: CD68 (96%), LYS (42%), CD1a (100%), S100 (100%), CD21/35 (0%). There were two morphological variants: cytologically typical (n=17) designated LCT; and cytologically malignant (n=9) designated Langerhans cell sarcoma (LCS). The LCS were often not easily recognized morphologically as LC-derived, but were diagnosed based on CD1a staining. LCT and LCS differed in median age (33 versus 41 years), male:female ratio (3.7:1 versus 1:2), and death rate (31% versus 50% DOD). Four LCT patients had systemic involvement typical of Letterer-Siwe disease; (iii) follicular dendritic cell tumour/sarcoma (FDCT) (n=13) which expressed: CD68 (54%), LYS (8%), CD1a (0%), S100 (16%), FDC markers CD21/35 (100%), EMA (40%). These patients were adults (median age 65 years) with predominantly localized nodal disease (75%) and low mortality (9% DOD); (iv) interdigitating dendritic cell tumour/sarcoma (IDCT) (n=4) which expressed: CD68 (50%), LYS (25%), CD1a (0%), S100 (100%), CD21/35 (0%). The patients were adults (median 71 years) with localized nodal disease (75%) without mortality (0% DOD). In conclusion, definitive immunophenotypic classification of histiocytic and accessory cell neoplasms into four categories was possible in 93% of the cases using six antigens detected in paraffin-embedded sections. Exceptional cases (7%) were resolvable when added morphological and ultrastructural features were considered. We propose a classification combining immunophenotype and morphology with five categories, including Langerhans cell sarcoma. This simplified scheme is practical for everyday diagnostic use and should provide a framework for additional investigation of these unusual neoplasms.Histopathology 08/2002; 41(1):1-29. · 2.86 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Neoplasms of reticular dendritic origin are extremely rare and include the follicular dendritic cell sarcoma (FDCS) and the interdigitating reticulum (or dendritic) cell sarcoma (IDCS). In this article, we review the literature pertaining to the two diseases and describe clinical observations and salient pathologic features, including information provided by authors of FDCS and IDDCS reports. We performed a computerized database search for published articles regarding FDCS and IDDCS. The articles were evaluated critically by the authors. Simple descriptive statistics were used to analyze the data. There are 51 cases of FDCS and 21 cases of IDDCS that are well documented in the literature. The pathologic diagnosis of FDCS and IDDCS is often challenging and requires morphologic, immunophenotypic, cytochemical, and electron-microscopic analysis. Patients with FDCS usually present with cervical or axillary lymphadenopathy, but extranodal disease has been described. In at least some patients, preexisting Castleman's disease has been recognized. Resected localized disease may be prevented from recurrence by consolidative radiotherapy. Chemotherapy regimens have shown nondurable antitumor activity in FDCS. Patients with IDDCS usually present with lymphadenopathy. The clinical course of IDDCS has been variable, but it seems to be more aggressive than that of FDCS. Variable degrees of remission may be achieved with chemotherapy. FDCS and IDDCS are rare neoplasms that may pose difficulty in pathologic diagnosis. IDDCS seems to display a more aggressive behavior than FDCS. Patients with IDDCS and FDCS can eventually die of disease progression. The role of chemotherapy and radiotherapy is not clearly defined.American Journal of Hematology 11/1998; 59(2):161-7. · 4.00 Impact Factor