Sustained remission after ABVD treatment for interdigitating dendritic cell sarcoma

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare neoplastic proliferation of dendritic cells [1]. EBV and HSV8 viral infections are thought to be involved in its pathogenesis, but understanding their role requires further studies [2]. IDCS usually affects adults with a median age at diagnosis of 51 years. Clinical manifestation usually includes lymphadenopathy, but extranodal presentation has also been reported [1, 3, 4]. Up-to-date studies on IDCS treatment and outcome are based on single case reports or very small series [1–6]. It was demonstrated that this neoplasm displays an aggressive clinical course, but a standard therapeutic approach has not been established so far. Different treatment modalities have been attempted, but they have mostly been ineffective [6, 7]. Herein, we report on a 22-year-old female with IDCS manifested as peripheral and mediastinal lymphadenopathy, who responded completely to ABVD (adriamycin, bleomycin, vinblastine, dacar-bazine). A 22-year-old, previously healthy female was referred to our Haematological Department with a diagnosis of IDCS. Eight months prior to admittance she accidentally noticed an enlarged cervical lymph node. No general symptoms were present at that time. The diagnostic work-up was started. Common reactive causes of lymphade-nopathy were carefully excluded. Computed tomography (CT) scan of the neck revealed bilaterally enlarged lymph nodes (size 4.5 cm × 3.5 cm). Chest X-ray and CT scan of the abdomen did not detect any abnormalities. Positron emission tomography (PET) scan performed in February 2010 showed increased glucose uptake in the right cer-vical area. Histological examination of the excised lymph node was done and the study revealed sheets of spindled cells with a whorled pattern. The nuclei of these cells were spindled or ovoid (Fig. 1). There were some multinucle-ate cells. The cytoplasm was slightly eosinophilic. Among these spindled cells, there were numerous lymphocytes and plasma cells. Necrosis was absent. The neoplas-tic cells were strongly positive for S-100 protein (Fig. 2), fascin (Fig. 3) and vimentin. They weakly expressed CD68 (Fig. 4) and CD45 antigens. CD1a and CD30 were absent, whereas expression of CD4 was positive. A preliminary diagnosis of IDCS was proposed. Due to the rarity of this disease , the lymph node was examined by two other pathologists and the final diagnosis was established three months later. On admission to our Centre the physical examination was normal except the enlargement of the right cervical lymph node. Blood tests showed haemoglobin concentration of 12.8 g/dl, white blood cell (WBC) count of 6.8 …