ABSTRACT: We describe a case of a 44 year-old woman diagnosed with follicular dendritic cell sarcoma (FDCS). FDCS is a very rare disease affecting the dendritic antigen presenting cells and is often misdiagnosed. Surgery is considered the best treatment modality, followed by chemotherapy. In our case, surgical excision was not possible, therefore the patient received two lines of chemotherapy followed by bone marrow allotransplantation, then a third line of chemotherapy with a complete metabolic response seen on PET/computed tomography (CT) follow-up 29 months later. A review of the literature has been performed.
KEYWORDS: intraperitoneal, follicular dendritic cell sarcoma (FDCS), chemotherapy, bone marrow allotransplantation
RECEIVED: June 9, 2013. RESUBMITTED: March 23, 2014. ACCEPTED FOR PUBLICATION: March 24, 2014.
ACADEMIC EDITOR: William C. S. Cho, Editor in Chief
TYPE: Case Report
FUNDING: Authors disclose no funding sources.
COMPETING INTEREST: Authors disclose no potential conflicts of interest.
COPYRIGHT: © the authors, publisher and licensee Libertas Academica Limited. his is an open-access article distributed under the terms of the Creative Commons CC-BY-NC 3.0 License.
Follicular dendritic cell sarcoma (FDCS) is a neoplastic proliferation of spindled to ovoid cells showing morphologic and phenotypic features of follicular dendritic cells and was firstly described by Monda in 1986.1 Only few case reports and retrospective series have been published.2–15 FDCS mainly affects head and neck lymph nodes.16 Intraperitoneal location of FDCS is a very uncommon discovery and is associated with a particularly aggressive clinical course.2,13
In this report, we present a case of advanced intraperitoneal FDCS treated successfully with chemotherapy and bone marrow allotransplantation.
A 44 year-old woman with no known previous medical history, presented with a painless periumbilical mass, associated with intermittent constipation. An abdominal computed tomography (CT) was performed and showed a homogeneous enhancing mass in the lesser omentum, 5 cm in diameter and located in front of the pancreas.
Another subhepatic heterogeneous enhancing mass of 5.9 × 8.6 × 7 cm was also detected and a retroperitoneal lymph node without involvement of adjacent structures, suggestive of lymphoma (Fig. 1A and B). The 18-FDGPET/CT showed two hypermetabolic masses, corresponding to those described on CT, with multiple retroperitoneal and right iliac hypermetabolic lymph nodes (Fig. 2).
A laparoscopic excisional-biopsy of the main mass was performed to confirm the suspicion of lymphoma diagnosis. Macroscopically, an encapsulated nodular mass measuring 8.5 × 5.5 × 5.5 cm was identified. Histopathologic assessment of the resected specimen showed clusters of small lymphocytes and epithelioid cells with eosinophilic cytoplasm and indistinct borders (Fig. 3A).
We note sheets of ovoid cells with vesicular nuclei and pale eosinophilic cytoplasm. We note also mitotic activity, syncitial appearance, and the presence of interspersed lymphocytes (Fig. 3B). Immunohistochemical staining showed cells that were strongly positive for the FDCS marker CD23 (Fig. 3C) and negative for CD20, S-100-protein, and CD1a. ALK was also negative.
No monoclonal rearrangement of the T-cell receptor gamma-chain, of immunoglobulin heavy-chain gene or of immunoglobulin kappa light-chain gene was revealed by PCR. These findings were considered diagnostic of FDCS. Multidisciplinary discussion of the case agreed on a classical lymphoma-based chemotherapy with cyclophosphamide, adriamycin, vincristine, and prednisone (CHOP, six courses).