A response-adapted approach to treatment using chemotherapy (CT) and radiotherapy (RT) may benefit patients with early extranodal nasal-type NK/T-cell lymphoma (ENKTCL), according to study results reported in the American Journal of Hematology.
“Due to its rarity and heterogeneity, optimizing the combination and sequence of RT and CT for early-stage ENKTCL remains challenging,” explained the researchers in their report.
They conducted a multicenter, retrospective analysis of outcomes for 1360 patients enrolled in the China Lymphoma Collaborative Group database who were treated with RT with or without nonanthracycline-based CT for ENKTCL. Treatments involved RT alone or sequential therapies including either RT prior to CT (RT+CT) or CT prior to RT (CT+RT). The patient population was stratified according to the nomogram-revised risk index.
A total of 382 patients were treated with RT alone, 131 were treated with RT+CT, and 847 patients were treated with CT+RT. Patients with high- or intermediate-risk status who received both RT and CT showed a significantly higher 5-year overall survival (OS) rate than did those who received RT alone (73.2% vs 60.9%, respectively; P <.001). For survivors, the median study follow-up time was 43 months.
High-/intermediate-risk patients also experienced a significant 5-year progression-free survival (PFS) benefit with RT and CT compared with RT alone (63.6% vs 54.2%, respectively; P <.001). Low-risk patients showed no significant difference for either OS or PFS.
The order of sequencing with RT and CT did not appear to affect OS or PFS rates for high- and intermediate-risk patients. The 5-year OS rates were for high-/intermediate-risk patients given RT+CT and CT+RT were 77.7% and 72.4%, respectively (P =.290); 5-year PFS rates were 67.1% and 63.1%, respectively (P =.592).
Patients who showed a complete response following induction CT did not show significantly different OS or PFS rates whether they began RT during or after the first 3 cycles of CT; however, among patients who did not have a complete response, early RT resulted in better PFS compared with late RT (63.4% vs 47.6%, respectively; P =.019).
To improve care for patients with ENKTCL, particularly with high-/intermediate-risk early-stage disease, the researchers recommended a response-adapted strategy involving CT+RT or RT+CT.
Qi SN, Yang Y, Zhang YJ, et al. Risk-based, response-adapted therapy for early-stage extranodal nasal-type NK/T-cell lymphoma in the modern chemotherapy era: a China Lymphoma Collaborative Group (CLCG) study [published online May 25, 2020]. Am J Hematol. doi: 10.1002/ajh.25878