[Clinical features and prognosis of nasal type NK/T cell lymphoma]

To investigate the clinical features, treatment modalities and the prognosis of nasal type NK/T cell lymphoma.

The data of 39 such patients treated from June 2000 to December 2003 were retrospectively reviewed. Twenty three patients were treated by combined chemoradiotherapy, basing on anthracycline-containing CHOP or similar regimens (median 5 cycles). Eleven patients by chemotherapy alone, 2 by radiotherapy alone and 2 aged patients by palliative chemotherapy or radiotherapy. Radiotherapy was given by high energy photon ray combined with electron beam with a median curative dose of 56 Gy in conventional fractionation. Bivariate correlations and univariate prognostic factors were analyzed.

Median follow-up time for the 21 patients who were still alive was 22.5 months. The overall remission rate (RR) after initial treatment was 66.7% (21 CR, 3 PR). Chemotherapy alone got a CR rate of only 37.5%. The overall local control rate was 59.4%. Local relapse rate after curative radiotherapy was 25.0%. Radiotherapy was positively correlated with local control (P = 0.000) and time to disease progression (TTP, P = 0.002). Skin and intestine were among the extranodal relapse sites. Fifteen patients had highly aggressive tumors with a median survival time of only 5 months. Univariate analysis showed that significant favorable survival prognostic factors were: radiotherapy (P = 0.001); lower risk International Prognostic Index (IPI, P = 0.001); complete remission after primary treatment (P = 0.000); pre-diagnostic history > 2 months (P = 0.024); and free of skin involvement (P = 0.034).

Most of nasal type NK/T cell lymphoma are in early stage when diagnosed. Radiotherapy remains to be the mainstay of treatment. Combined chemoradiotherapy needs further improvement for the progressive disease type. Some patients may have highly aggressive tumors with poor prognosis. Optimal prognostic factors and individualized treatment regimens need to be investigated.