Extranodal NK/T Cell Lymphoma, Nasal Type, Presenting with Primary Cutaneous Lesion Mimicking Granulomatous Panniculitis: A Case Report and Review of Literature
Panitta Sitthinamsuwan MD*, Tawatchai Pongpruttipan MD*, Leena Chularojmontri MD**, Penvadee Pattanaprichakul MD**, Archrob Khuhapinant MD, PhD***, Sanya Sukpanichnant MD*
Affiliation : * Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand **Department of Dermatology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand *** Division of Hematology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : Cutaneous extranodal NK/T-cell lymphoma, nasal type (NK/T) is relatively rare, associated with aggressive
behavior and poor prognosis. Histopathological findings, immunohistochemical study, and EBV-encoded RNA (EBER) in situ
hybridization are essential for the diagnosis.
Case Report : A 54-year-old Thai man with NK/T of the nasal cavity initially presented with cutaneous NK/T mimicking
granulomatous panniculitis. The skin biopsies were performed twice due to the marked necrosis in the first one. The second
biopsy revealed small, medium, and large atypical lymphoid cells infiltrating fat lobules with necrotic foci and granulomatous
reaction. Within the granulomatous inflammation, the atypical lymphoid cells showing involvement of the blood vessel
(angiocentricity) were noted. Immunostaining demonstrated that the atypical lymphoid cells marked with CD3, CD56, and
TIA-1, but they did not mark with CD5, CD20, CD15, or CD 30. EBER in situ hybridization was positive.
Conclusion : Cutaneous NK/T can produce granulomatous panniculitis. The recognition of atypical lymphoid cells showing
angiocentricity together with immunohistochemistry and EBER in situ hybridization are crucial for the correct diagnosis.
Keywords : Extranodal NK/T-cell lymphoma, Epstein Barr virus, Cutaneous lymphoma
