Background: Mature T and NK cell lymphomas are rare aggressive diseases, comprising about 10% to 15% of non–Hodgkin lymphoma (NHL), showing geographic variation with certain types. A retrospective study was carried out to analyse the distribution and frequency of various types of mature T and NK/T cell lymphomas diagnosed at our Institute.

Results: 245 cases of mature T and NK cell lymphomas were diagnosed forming nearly 10% of all cases of NHL, with Peripheral T cell lymphoma– Not otherwise specified(PTCL–NOS) the commonest type, followed by Anaplastic Large Cell Lymphoma (ALCL). Forty seven cases had extranodal presentation, upper aero digestive tract being the commonest site.

Conclusions: We found a higher incidence of PTCL NOS and ALCL cases and a lower frequency of Angioimmunoblastic T Cell Lymphoma (AITL) as compared to the western studies.