Curability Of Radiotherapy In Elderly Patients With Earlystage Extranodal Nasal-Type Nk/T-Cell Lymphoma: A Multicenter Study From The China Lymphoma Collaborative Group (Clcg)

The purpose of the present study was to determine the curability of radiotherapy and potential benefit of a new chemotherapy regimen in elderly patients with early-stage extranodal nasal-type NK/T-cell lymphoma (NKTCL). In a multicenter study, 321 elderly patients (age > 60 years) with early-stage NKTCL were reviewed retrospectively. Patients received radiotherapy alone (n = 87), chemotherapy alone (n = 59), or combined modality therapy (CMT, n = 175). Patients were classified into groups of either low- or high-risk using four prognostic factors. Observed survival in the study cohort versus expected survival in the age- and sex- matched general Chinese population was plotted by using a conditional approach and compared by standardized mortality ratio (SMR). Radiotherapy achieved a favorable prognosis in elderly early-stage patients and significantly improved prognosis compared with chemotherapy alone. The 5-year overall survival (OS) and progression-free survival (PFS) were 61.2% and 56.4% for radiotherapy compared with 44.7% and 38.3% for chemotherapy alone ( P < 0.001). Low-risk patients showed significantly improved survival compared with high-risk patients. Patients treated with a new CMT regimen demonstrated a significantly improved PFS compared with the old CMT regimen (71.2% vs. 44.2%, respectively, P = 0.017). Low-risk patients following radiotherapy (SMR, 0.703; P = 0.203) and high-risk patients that achieved PFS at 24 months (SMR, 1.490; P = 0.111) after radiotherapy showed survival equivalent to the general Chinese population. Our findings highlight the curability of radiotherapy and provide a risk-adapted follow-up and counsel system for elderly early-stage patients.