Clinicopathologic features and treatment outcome of mature T-cell and natural killer-cell lymphomas diagnosed according to the World Health Organization classification scheme: a single center experience of 10 years.

BACKGROUND: Data on mature T-cell and natural killer (NK)-cell lymphomas diagnosed with the World Health Organization (WHO) classification scheme are scarce. They are regarded to be more common in Asian populations. METHODS: Consecutive T-cell and NK-cell lymphomas classified according to the WHO scheme within 10 years in a Chinese population were reviewed. RESULTS: There were 148 cases, constituting 16.6% (T-cell, n=90, 10.1%, NK-cell, n=58, 6.5%) of all non-Hodgkin lymphomas in this period. There was a male predominance (male:female = 2.5), young age at diagnosis (median age 50 years, range 8-86) and frequent extranodal presentation. Commonest T-cell lymphomas included anaplastic large cell lymphoma (ALCL, n=25, median age 35 years, nodal 60%, stage I/II 60%), peripheral T-cell lymphoma, unspecified (PTCL, n=24, median age 54 years, nodal 42%, stage I/II 42%), and angioimmunoblastic T-cell lymphoma (AILT, n=19, median age 67 years, nodal 95%, stage I/II 26%). Overall frequencies of T-cell lymphomas were comparable to Western patients. AILT, PTCL and ALCL were aggressive with a poor outcome. NK-cell lymphomas were predominantly extranodal (96%) and aggressive, with a frequency much higher than Western patients. CONCLUSIONS: The apparent high prevalence of T-cell and NK-cell lymphomas in the Chinese was due to more frequent NK-cell but not T-cell lymphomas.