Adjuvant chemotherapy was associated with improved overall survival rates at 3 years in patients who had surgery for gastroesophageal cancer, based on retrospective data from more than 10,000 adults.
Preoperative chemoradiotherapy and resection has shown benefits in patients with gastroesophageal adenocarcinoma, but the potential benefits of adjuvant chemotherapy (AC) after surgery in these patients has not been well studied, wrote Ali A. El Mokdad, MD, of the University of Texas Southwestern Medical Center, Dallas, and his colleagues (JAMA Oncol. 2017 Sep 21. doi: 10.1001/jamaoncol.2017.2805).
The researchers reviewed data from 10,086 patients in the National Cancer Database during 2006-2013. Of these, 814 (8%) received adjuvant chemotherapy after surgery and 9,272 (94%) received no additional intervention beyond postoperative observation. The average age of the patients was 61 years, and 88% were men.
The average survival rates at 3 years after surgery were 40 months for the adjuvant group and 34 months for the observation group (hazard ratio, 0.79). The overall survival rates in the adjuvant group were 94%, 54%, and 38% at 1,3, and 5 years, respectively, compared with rates of 88%, 47%, and 34%, in the observation group.
The findings were limited in part by the retrospective nature of the study, the researchers said. In addition, “the estimated effect of AC on overall survival is subject to selection bias and immortal time bias given that the study was observational,” they noted.
However, the results support the addition of chemotherapy for gastroesophageal surgery patients, and “provide compelling motivation to explore the potential benefit of adjuvant chemotherapy in a randomized clinical trial,” they said. “A two-arm phase 2 trial design using recurrence-free survival as a primary endpoint is an appealing first step,” they added.
The researchers had no financial conflicts to disclose.