The significance of combining radiotherapy with chemotherapy for early stage extranodal natural killer/T-cell lymphoma, nasal type: a systematic review and meta-analysis.

Abstract Radiotherapy is regarded as a primary treatment for early stage extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTL). However, whether combined modality treatment (CMT) comprising radiotherapy and chemotherapy is necessary remains controversial. A systematic review and meta-analysis of studies was performed to evaluate the significance of combining radiotherapy with chemotherapy for early stage ENKTL. Comparison of CMT and radiotherapy alone (RT) showed no significant difference by the measurement of complete response (CR) (odds ratio [OR] 1.07; 95% confidence interval [CI] 0.73-1.58; p = 0.73), 5-year overall survival rate (OS) (HR 0.73; 95% CI 0.45-1.19; p = 0.21) and progression-free survival rate (PFS) (HR 0.76; 95% CI 0.50-1.17; p = 0.21). Additional chemotherapy did not decrease systemic failure (OR 1.52; 95% CI 0.97-2.40; p = 0.07), as well as locoregional failure (OR 0.94; 95% CI 0.52-1.73; p = 0.85). The results may support the assertion that the combination of radiotherapy with chemotherapy cannot improve treatment outcomes, but rather it increases adverse effects and financial costs. However, these results should be interpreted with caution.