Extranodal NK/T-Cell Lymphoma, Nasal Type: Experience of Management in a Referral Hospital in a Development Country.

Extranodal NK/T-cell lymphoma, nasal type is an entity of difficult diagnosis. It is characterized by damage and vascular destruction, necrosis, cytotoxic phenotype and Epstein Barr virus association. It is prominent in Asia, Mexico, Central and South America, predominantly in men.

It is an observational, descriptive and retrospective study, based on medical records of NK/T-cell lymphoma patients of the General Hospital of Mexico between 1992-2009.

Of 632 non-Hodgkin lymphomas (NHL), 113 had a T cell lymphoma. Only 32 cases (28.3%) were eligible for the study. The age range was 19-56 years with a media of 42. The male:female ratio was 2.2:1. The most frequent clinical presentation symptoms were nasal obstruction, facial swelling and pain. Central nervous system involvement was present only in two cases and bone marrow infiltration in one. Seventy eight percent were on clinical stages I or II and 56% had B symptoms. In 7/10 patients the Epstein Barr association was documented by hystopathological study. The treatment was completed in 31/32 individuals. Fifty five percent showed some response, regardless of the therapy used. The CHOP regimen was the first line treatment in 80.6% of cases and only 13% received fractionated radiotherapy as initial treatment. The CHOP arm had an overall response rate of 60% (complete remissions, unconfirmed complete remissions, partial remissions), and 100% of the patients in the radiotherapy arm presented complete response. Most patients of the radiotherapy arm were on stage IE. The overall survival rate was 63% at 36 months. The average follow-up was 40 months. There were no differences in overall survival rates between the two arms, but the radiotherapy arm had a higher rate of complete remissions.

In this study we report the clinical features and response to treatment of the patient population treated at the General Hospital of Mexico. The results are similar to other international reports. Although the incidence of NK/T-cell lymphoma is low, it is necessary to standardize its treatment and these preliminary data warrant further trial of radiotherapy as the initial treatment and chemotherapy as consolidation for advanced stages of the disease.

No relevant conflicts of interest to declare.