Short-term efficacy and long-term survival of nasopharyngeal carcinoma patients with radiographically visible residual disease following observation or additional intervention: A real-world study in China.

Background: To explore the short- and long-term outcomes in patients with nasopharyngeal carcinoma (NPC) with magnetic resonance imaging (MRI)-detected residual disease at 3 months post-treatment who received intervention either promptly (0 month) or following observation (after an additional 3 months). Methods: A total of 272 patients with residual disease at 3 months post-treatment (observation [observation for additional 3 months]: 122, intervention [prompt intervention]: 150) were analyzed. Univariate and multivariate analyses were performed to examine the survival. Adverse events were analyzed in all patients. Results: Patients in the observation group had a lower 3-year overall survival (77.1% vs. 85.2%), progression-free survival (10.2% vs. 18.1%), and locoregional relapse-free survival (10.2% vs. 20.6%) (all p < .05), but not distant metastasis-free survival (83.8% vs. 78.4%, p = .189), whereas patients in the intervention group achieved higher complete remission (CR) rates (43.3% vs. 21.2%, p = .003). Patients who achieved CR after prompt intervention had a better survival rate than those who achieved observation-CR or non-CR (p < .001). Multivariate analyses revealed that a wait-and-see policy was an independent prognostic factor for impaired survival (p < .001). No significant differences of acute or late toxicities were observed between the two groups. Conclusions: Patients with NPC with MRI-detected residual disease 3 months post-radiotherapy should be encouraged to undergo prompt intervention rather than adopting a passive wait-and-see policy.