Follicular Dendritic Cell Tumor Research Articles

Repeated hepatectomies for recurrent follicular dendritic cell tumour of liver: a case report

Follicular dendritic cell tumour is a very rare tumour of unknown aetiology. We report a case of follicular dendritic cell tumour of liver which was treated with extended right hemihepatectomy but recurred twice in the remaining left lobe within 3 years. The recurrent tumours were removed by further liver resection. The mainstay of treatment for this rare tumour is surgical resection.

Angiomyoid and follicular dendritic cell proliferative lesions in Castleman's disease of hyaline-vascular type: a study of 10 cases.

Castleman's disease of hyaline-vascular type (HV CD) may rarely be associated with a confusing variety of stromal cell overgrowths and neoplasms. We report here on the pathologic and clinical findings of 10 such cases. In addition to the usual complex histoimmunophenotype of the stroma of HV CD and some unusual features that mimicked neoplasms, we observed focal proliferations of angiomyoid (five cases) and follicular dendritic cell type (five cases). The former were nonneoplastic growths featuring compact tangles of spindle cells, exhibiting immunoreactivity for smooth muscle actin and interpreted as vessel-related pericytes and myoid cells. The latter were neoplastic growths of oval to spindle cells intermixed with lymphocytes; the tumor cells grew in long, intersecting bundles, featured various degree of atypia, and expressed the markers of follicular dendritic cells (CD21, CD35, KiM4p). The two types were clinically distinct. Four of five patients with angiomyoid proliferations were young women, who presented with an abdominal mass and were cured by surgery; that is, they had a clinical profile similar to that of patients with the stroma-rich variant of HV CD. The follicular dendritic cell proliferations were in older patients of either gender presenting with masses at various sites, recapitulating the profile of follicular dendritic cell tumors arising independently from HV CD; in three patients with long-term follow-up, recurrences or metastases developed at various intervals from the initial diagnosis (1 1/6, 3 1/2, and 11 years), and one patient died as a result. This study confirms the potential for, and the variety of, stromal cell proliferations in HV CD. Because their biologic behavior differs, correct identification of these various proliferative lesions is clinically important.

Follicular Dendritic Cell Tumor in Castleman's Disease

We report two cases of follicular dendritic cell tumor associated with Castleman's disease, one of the hyaline vascular type and one a mixed hyaline-vascular and plasma cell type. The reactive lymphoid follicles in both cases contained a proliferation of abnormal follicular dendritic cells characterized by enlarged, irregular contoured nuclei and prominent nucleoli (in-situ component). Both tumors had similar histology. They were vaguely fascicular and composed by eosinophilic, ovoid to spindled cells with vesicular nuclei and prominent nucleoli admixed with small lymphocytes. Some of these cells seen in the reactive follicles were similar in appearance to the ones seen in the adjacent invasive tumors. The association of follicular dendritic cell tumor with Castleman's disease and the presence of in-situ follicular dendritic cell tumor within reactive lymphoid follicles suggests that there may be a progression from dysplastic follicular dendritic cells to follicular dendritic cell tumor in Castleman's disease. The sequence of events and the likelihood that patients with Castleman's disease showing follicles with dysplastic changes will develop follicular dendritic cell tumors is not known at this time owing to the limited number of cases reported.

Follicular Dendritic Cell Tumor of the Mesentery

Follicular dendritic cell (FDC) tumor is an exceedingly rare malignant neoplasm and occurs mainly in the cervical lymph nodes. We report a mesenteric FDC tumor occurring in a 66-year-old female, that manifested with intraabdominal multifocal recurrence 7 years after resection of the primary tumor. Histologically, both primary and recurrent tumors were composed of oval to spindle cells with paley eosinophilic cytoplasms, indistinct cell borders, round to elongated nuclei with clear or finely dispersed chromatin, and medium to large nucleoli. Characteristically, the tumor cells were growing in sheets, fascicles, and sometimes in whorls and a storiform pattern. In addition, focal necrosis, nuclear pleomorphism and abnormal mitoses were also observed. The neoplastic cells were intimately admixed with small lymphocytes. The diagnosis was confirmed by positive immunoreactivity with CD21 and CD35 antibodies and by ultrastructural demonstration of convoluted interdigitating cell processes connected by scattered desmosome-like junctions. Although our case showed a low proliferative activity evaluated by MIB-1, multifocal recurrence has occurred. The clinicopathologic features and differential diagnosis of FDC tumors are discussed with the review of the literature.

Follicular Dendritic Cell Tumor

Follicular dendritic cell (FDC) tumor is an extremely rare malignant neoplasm with approximately 17 well-documented cases in the literature. We report 13 additional cases of this distinctive neoplasm. There were seven men and six women, with a mean age of 46.5 years (range, 27-62 years). There was involvement of cervical lymph nodes (six cases), mediastinum (three cases), axilla, tonsil, spleen, and peripancreatic soft tissues (one case each). The neoplasms were grey to tan, ranging in size from 1 to 13 cm. They were formed by oval to spindle cells with eosinophilic cytoplasm growing in sheets and fascicles, with a focal storiform pattern and whorls reminiscent of those seen in meningioma. The nuclei were oval or elongated with thin nuclear membranes, inconspicuous or small eosinophilic nucleoli, and clear or dispersed chromatin. Typically, the tumor cells were intimately admixed with small lymphocytes, with a prominent perivascular cuffing. Multinucleated tumor cells were present in seven cases. Necrosis, marked cellular atypia, high mitotic rate, and/or abnormal mitoses were present in seven cases. The tumor cells were positive for CD21 (10 of 11), CD35 (10 of 11), Ki-M4p (seven of eight) Ki-FDRC1p (six of seven), vimentin (five of nine), and S100 protein (five of nine). One case stained with actin. In situ hybridization, done in six cases, did not show Epstein-Barr virus RNA sequences. Ultrastructural examination of eight cases showed long, complex, occasionally interdigitating cytoplasmic processes joined by desmosomes. The behavior of these tumors is more akin to that of a low-grade soft tissue sarcoma than a malignant lymphoma and is characterized by local recurrences and occasional metastases. Two patients died of tumor, two were alive with recurrent or metastatic disease, eight were alive with no disease, and one was lost to follow-up.

Extranodal occurrence of follicular dendritic cell tumor

Extranodal occurrence of follicular dendritic cell tumor

Follicular Dendritic Cell Tumors of the Oral Cavity

Follicular dendritic cell tumors are uncommon, and all the reported cases have occurred as primary lymph node tumors. We report two cases in the oral cavity, one in the soft palate and one in the tonsil. The tumors were characterized by sheets, whorls, and storiform arrays of spindly and syncytial-appearing cells with oval nuclei, fine chromatin, distinct nucleoli, and occasional nuclear pseudoinclusions. Multinucleated forms were present and were prominent in one case. An unusual feature was the presence of irregular pseudovascular spaces, which could raise a concern for vascular neoplasm. Because the tumors showed cohesive growth and a sharp interface with the fibrous stroma, they could also be mistaken for carcinoma, sarcoma, or melanoma. After radiation therapy, the palatal tumor showed a greater degree of nuclear pleomorphism, numerous nuclear pseudoinclusions, and striking nuclear grooving and foldings, mimicking interdigitating reticulum cell tumors. The diagnosis in both cases was confirmed by immunoreactivity with CD21 and CD35 and by ultrastructural demonstration of interdigitating cell processes with desmosomes. Both tumors also showed unexpected immunoreactivity with muscle-specific actin. Follicular dendritic cell tumor merits wider recognition of its possible extranodal occurrence as well as its full morphological spectrum in order to better define its behavior.