Second to none.
Top Line: Can treatment be de-escalated for favorable risk nasopharyngeal carcinoma (NPC)?
The Study: Last year, we learned that a next-gen platinum agent, lobaplatin, reduced toxicity compared to cisplatin for NPC. Another approach is to reduce the cumulative amount of chemo. EBV titers are an important prognostic factor for EBV-mediated nasopharyngeal carcinoma (NPC)--with lower pretreatment titers being associated with better outcomes. This randomizedphase 2 trial sought to determine if 2 cycles instead of 3 cycles concurrent cisplatin reduced toxicity while maintaining non-inferior progression-free survival in patients with low risk, locally advanced (stage III-IVb) NPC. Low risk was defined as <4000 copies/mL plasma EBV DNA. Radiation consisted of 68-70 Gy in 30-33 fractions with multiple lower dose levels, and cisplatin (100 mg/m2) was administered on days 1, 22, and +/- 43. Of >500 patients screened, 68% were considered low risk. Chemo compliance was higher in the 2-cycle group (99% v 89%), and half as many patients required dose reduction (18% v 36%). Toxicity was significantly lower across the board with 2 vs 3 cycles cisplatin, including grade 3+ mucositis (15.1% v 24.8%) and dermatitis (1.2% v 5.5%). All-grade late toxicities were also lower with 2 cycles, however the rates of late grade 3+ toxicities were similar. At 3 years, progression free survival was deemed non-inferior with 2 cycles cisplatin (88.0% v 90.4%), and there were no differences in overall survival, distant metastasis, or locoregional relapse. After treatment, 98% of patients in both arms had undetectable EBV DNA.
TBL: This single-center phase 2 study suggests a lower cumulative dose of concurrent cisplatin may reduce toxicity with comparable 3-year PFS for low risk, locally advanced NPC. | Li, J Clin Oncol 2022