Verma V, et al. - This study was planned to assess the overall survival (OS) in patients with metastatic (M1) nasopharyngeal cancer (NPC) undergoing chemotherapy alone versus chemoradiotherapy (CRT). Compared to patients receiving chemotherapy alone, patients undergoing definitive radiotherapy (RT) and chemotherapy experienced higher survival. Authors suggested risk stratification and patient selection for such combined modality interventions as critical.

Methods

• Researchers searched the National Cancer Data Base for M1 NPC cases.
• They excluded patients undergoing no/unknown chemotherapy and/or with unknown/nondefinitive radiotherapy (RT) doses (<60 Gy).
• They determined clinical factors associated with RT administration with logistic regression analysis.
• They evaluated OS between both cohorts using Kaplan-Meier analysis.
• Cox proportional hazards modeling was used to assess factors associated with OS.
• Between matched populations, survival was then evaluated using inverse-probability–weighted regression adjustment.
• In this study, OS between groups was also measured in patients surviving ≥1 and ≥3 years to address bias from poor-prognostic subsets (eg, widely disseminated disease), and those receiving CRT ≤30 and ≤60 days of each other (surrogates for concurrent CRT) versus >30 and >60 days (sequential) of each other.

Results

• This study included 555 patients; 296 (53%) received chemotherapy alone and 259 (47%) underwent CRT.
• Researchers noticed that patients undergoing CRT more often had private insurance (P=.001) and lived in areas with higher education levels (P=.028).
• In the chemotherapy-only and CRT cohorts, median OS were 13.7 and 25.8 months, respectively (P<.001); between matched populations, the differences persisted (P < .001).
• Multivariate analysis suggested that receipt of additional RT independently predicted for improved OS (P < .001).
• When evaluating patients surviving for ≥1 (P < .001) and ≥3 (P=.002) years, OS differences between cohorts remained apparent .
• Improved OS was observed among patients who received concurrent or sequential CRT compared to those receiving chemotherapy alone, for both the 30-day (P < .001) and 60-day cutoffs (P < .001).