Abstract

Background: Primary cutaneous T cell lymphoma is a diverse and rare group of diseases with clinical manifestations that, if not biopsied, are easily confused with benign skin diseases. Objective: To determine some clinical features of primary cutaneous T cell lymphomas and classify them according to the 2018 update of World Health Organization and European Organisation for Research and Treatment of Cancer classification. Methods: a case series study with 39 cases of primary cutaneous T cell lymphomas diagnosed at Pathology Department of University Medical Center at Ho Chi Minh city from 01/2018 to 02/2022. Results: Median age at diagnosis is 59 years old. Male:Female ratio is 1:2.3. In order of frequency, diagnoses were: subcutaneous panniculitis-like T cell lymphoma (35.8%), mycosis fungoides (28.2%), primary cutaneous anaplastic large cell lymphoma (15.4%), peripheral T cell lymphoma not otherwise specified (7.7%), extranodal NK/T cell lymphoma, nasal type (7.7%), primary cutaneous CD4 + small/medium T cell lymphoproliferative disorder (2.6%) and primary cutaneous CD8+ aggressive epidermotropic T- cell lymphoma (2.6%). Subcutaneous panniculitis-like T cell lymphoma always presents as subcutaneous nodule-tumor (100%); the most common site is lower extremities (71.4%). Mycosis fungoides has various appearance of skin lesions (36.4%) including patch-plaque (100%), and usually involves in trunk (90.9%). Extranodal NK/T cell lymphoma, nasal type always has skin ulcer (100%). Conclusion: The study documented the frequence and clinical characteristics of each subtype of primary cutaneous T cell lymphoma. The most common were subcutaneous panniculitis- like T cell lymphoma and mycosis fungoides. Although the morphology and location of skin lesions in the subtypes overlap, they still aid in the diagnosis of skin lymphoma.