Pediatric follicular dendritic cell sarcoma of the head and neck: a case report and review of the literature.

OBJECTIVE: Follicular dendritic cell sarcoma is a rare disease with a non-specific and insidious presentation that is further complicated by difficult diagnostic and therapeutic assessment. METHODS: The database PubMed was searched for reports of follicular dendritic cell sarcoma between 1986 (first case published) and 2012. All of the articles presenting informations regarding one or more cases of follicular dendritic cell sarcoma of the head and neck region, in patients less than 18 years of age, were included. The reference lists for pertinent reports were also scanned to ensure that all relevant literature was included. RESULTS: We present a case of a 14 year-old girl, with a 2-month history of a right-sided level II neck mass. After a carefull radiologic evaluation the mass was resected combined with a right selective neck dissection. Histology with immunohistochemical staining was positive for follicular dendritic cell sarcoma. No recurrence was seen after 31 months follow-up. The literature search identified six more cases of pediatric follicular dendritic cell sarcoma of the head and neck. This is the first female patient with follicular dendritic cell sarcoma in the pediatric population. CONCLUSIONS: Current treatment of head and neck follicular dendritic cell sarcoma consists of wide radical resection, with associated radiotherapy or chemotherapy only for cases with aggressive disease such as extracapsular invasion, tumor size ≥6 cm or after failure of the first-line surgical treatment.

Folliculocentric B-cell-rich follicular dendritic cells sarcoma: a hitherto unreported morphological variant mimicking lymphoproliferative disorders.

We report three cases of follicular dendritic cell sarcoma (FDCS) showing a hitherto undescribed histological pattern consisting of nodular tumor growth associated with small B lymphocytes. FDCS tumor cells consistently showed large epithelioid features and were intermingled with small lymphocytes in the nodules in two cases, whereas they formed cohesive aggregates surrounded by lymphocyte mantle in the other. These features were easily confused with lymphomatous proliferations and, in particular, subtypes of Hodgkin lymphoma, high-grade follicular lymphoma, and germinotropic large B-cell lymphomas. The diagnosis was established by the use of a broad panel of antibodies that showed a variable expression of the FDC markers CD21, CD23, CD35, clusterin, podoplanin, claudin 4, epidermal growth factor receptor, and CXCL13. The associated B lymphocytes revealed a mantle zone B phenotype, with expression of CD20 and PAX5, together with TCL1 and IgD. Of notice, in all cases, morphological features suggesting hyaline-vascular Castleman disease were recognized in the interfollicular areas, containing scattered epithelioid cells similar to those found in the nodules, thus providing a useful clue for FDCS diagnosis. Of the 3 cases, 1 presented multiple recurrences unresponsive to chemotherapy and radiotherapy and finally died of disease 14 years after diagnosis. This study further emphasizes the extreme variability of morphological presentation of FDCS and expands the spectrum of lesions showing a nodular growth pattern occurring in human lymph nodes.