Successful Use of Brentuximab Vedotin for Treatment of CD30-positive Primary Cutaneous Extranodal Natural Killer/T-Cell Lymphoma

A 75-year-old Chinese man with a history of diabetes mellitus presented with multiple tender dermal violaceous ulcerative nodules over his extremities, which have increased in size and extent since their appearance 3 months ago (Figure 1). He reported a history of weight loss without fever or nasal symptoms. Histology from skin punch biopsies taken from his left arm and left thigh showed sheet-like infiltrate of medium-to-large atypical lymphoid cells. Immunohistochemistry (IHC) revealed positive staining with cytoplasmic CD3, CD2, CD56, CD30 and granzyme B. IHC staining for CD30 was variably weakly positive in a minority of the atypical lymphoid cells, ranging from less than 5% positivity in the left thigh specimen and 10-20% weak positivity in the left arm specimen, where atypical lymphoid cells appear larger. Ki-67 proliferation fraction was 90%. There was widespread nuclear positivity for Epstein-Barr virus-encoded small RNAs (EBER). IHC staining was negative for CD10, CD79a, CD 123 and TCL1 (Figures 2 and 3). A Positron Emission Tomography and Computed Tomography (PETCT) showed multiple enhancing and hypermetabolic nodular skin lesions with no involvement of lymph nodes and other organs (Figure 4). He was diagnosed with high-risk, advanced stage primary cutaneous extranodal natural killer/T-cell lymphoma, nasal type (ENKTL-NT). He received upfront treatment with Brentuximab vedotin (BV) in addition to chemotherapy (Table 1) which resulted in complete response.