't-cell/natural killer-cell neoplasms presenting as leukemia- case series from single tertiary care center'

background: mature t/ nk-cell neoplasms are a rare group of disorders and their presentation as leukemia is even rarer. most of the previous studies have focused on mature b-cell lineage leukemias and there is a paucity of data on mature t/nk-cell lineage leukemias. we, therefore, planned this study to analyze their spectrum, frequency, morphology and immunophenotypic features. methods: all cases of lymphomas presenting as leukemia over a period of two and a half years were evaluated. detailed analysis of cases with t/nk-cell lineage was done for their clinical, hematological and immunophenotypic features. results: a total of 262 cases of mature lymphoid neoplasms presented as leukemia during the study period. of whom, only 8 (3.1%) cases were of t /nk-cell lineage and the remaining (96.9%) were of b-cell lineage. of 8 cases, 4 (50%) had t-prolymphocytic leukemia, 2 (25%) had chronic lymphoproliferative disorder- natural killer cell and 1 (12.5%) case of each t-large granular lymphocytic leukemia and hepatosplenic γ/δ t-nhl. conclusion: t/nk-cell leukemias are rare. along with clinical and morphological features, pattern of immunophenotypic markers is vital for their diagnosis and subcategorization.