Clinicopathological analysis of T-cell lymphoma in Taiwan according to WHO classification: high incidence of enteropathy-type intestinal T-cell lymphoma

Objectives: The clinicopathological characteristics of malignant lymphomas vary according to geography, especially for the T-cell lymphoma (TCL). The aim of this study is to demonstrate the incidence and clinicopathological characteristics of TCL in Taiwan according to WHO classification. Methods: Archival tissue from 600 malignant lymphomas during the period of 1995-2002 was retrieved, there were 74 cases diagnosed with TCL. Hematoxylin and eosin slides stained and other special studies were reviewed. All cases were reclassified according to the WHO classification. Clinical data, including age, gender, clinical staging, and follow-up, were scrutinized. Results: There were 52 males and 22 females with male predilectation. The incidence of TCL in malignant lymphoma was 12.3%. The most prevalent histologic subtype was peripheral T-cell lymphoma (PTCL), followed by nasal T-cell/Natural killer- (T-/NK-) cell lymphoma, T-lymphoblastic lymphoma (LBL), anaplastic large cell lymphoma, and enteropathy-type intestinal lymphoma (ETCL). Clinically, 39 cases (49%) had higher clinical stage (III/IV). Overall 2-year and 5-year survival rate was 51.4% and 34.7%, respectively. It was noteworthy that ETCL had high incidence rate (8.1%) and high mortality. There was significant difference in survival rates in respect of clinical stages and histological subtypes. Conclusions: TCL is relatively less frequent in Taiwan, compared to other countries in Asian and western countries. The most common histological subtypes are PTCL, unspecified and T-/NK-cell lymphoma. Five-year survival rate is 34.7%. ETCL has higher incidence rate in Taiwan. The clinical stage and histological subtypes are prognostic parameters in determining the survival rates.