NK/T‐Cell Lymphoma Presenting as Subcutaneous Nodules in a Previously Healthy Young Woman: an Unusual Granulomatous Component Found on Biopsy

Abstract

A 27‐year‐old previously healthy woman presented with an acute onset of multiple tender subcutaneous nodules and nasal congestion. Biopsy of an arm nodule revealed an atypical, dense, diffuse cellular infiltrate, predominantly involving the deep dermis and the subcutaneous fat lobules. The infiltrate consisted of a spectrum of small, medium to large sized lymphocytes with the large lymphocytes predominating. The lymphoid cells showed irregular nuclear contours, fine chromatin, and indistinct nucleoli. Mitoses were frequent. A significant granulomatous component was present. In foci the infiltrate revealed an angiotropic and angiodestructive pattern. Large areas of tumor cell necrosis were noted. The subcutaneous infiltration was reminiscent of a lobular panniculitis, with areas resembling subcutaneous panniculitis‐like T‐cell lymphoma. Special stains for infectious organisms were negative. The neoplastic cells were CD2+, CD7+, CD3‐, CD5‐, CD8+, CD56+, CD52+, TIA‐1+, perforin+, granzyme‐B+, and LMP‐1‐. The infiltrate was EBV+. Flow cytometry showed 93% of cells to be NK cells. Workup revealed many nodules in the abdominal wall, lungs, and liver as well as sinusitis. The patient failed CHOP and ICE chemotherapy. The nodules resolved after three cycles of L‐aspariginase, vincristine, and dexamethasone. NK/T‐cell lymphoma usually affects middle‐aged and older adults. This case contains an unusual granulomatous component on biopsy.