CMED in the treatment of nasal natural killer cell lymphoma with distant metastases.

Introduction: Nasal natural killer (NK) cell lymphoma that showed distant metastases generally showed an poor prognosis. We described a group of patients with these atypical presentation and that were treated with an intensive, short chemotherapy/radiotherapy regimen.

Methods: Sixty-one patients fulfilled the criteria for NK cell lymphoma with distant metastases and all have very poor prognostic factors: high clinical risk, multiple extranodal presentation and bulky disease (tumor mass >10 cm). They were treated with CMED (cyclophosphamide 2000 mg/m(2), iv, day 1, methotrexate 400 mg/m(2), iv, day 1(with leucovorin rescue), etoposide 400 mg/m(2) twice and dexametasone 40 mg daily for 4 days). If complete response (CR) was observed, they were received adjuvant radiotherapy (50 Gy) to nasal region. Patients with failure were treated with different salvage treatments.

Results: Forty nine patients achieved CR and 12 were considered failure, all patients that were failure and nine that relapse die secondary to tumor progression. Median follow-up were 46 months (range 34-68 months). Median has not been observed in relapse-free survival (RFS) and overall survival (OS). Actuarial curves at 5 years showed that RFS was 81% and OS was 65%. Treatment was well tolerated.

Conclusions: Nasal NK cell lymphoma with distant metastases is considered an rare clinical entity, probably is under diagnosis because it has been included as stage III and IV in previous reports, that showed an very poor RFS and OS. The treatment herein report could achieve good response and outcome, but it is evident that more specific and aggressive therapy is necessary in these setting of patients.