Introduction: Postoperative adjuvant radiation therapy (RT) and chemotherapy (aCRT) have been supposed to improve prognosis and outcomes in patients with node-positive thoracic esophageal squamous cell carcinoma (TESCC). Our aim was to analyze the impacts of interval between surgery and aCRT on prognosis, determining the optimal time interval.
Methods: We retrospectively reviewed 520 patients with TESCC between 2007 and 2015 treated with aCRT following radical esophagectomy without neoadjuvant chemotherapy and RT. These patients underwent RT (50-60 Gy) combined with 2-6 cycles chemotherapy after surgery. The time intervals were from 17 days to 145 days and divided into three groups: short interval group (≤28 days, S-Int group), medial interval group (≥29 and ≤ 56 days, M-Int group) and long interval group (≥57 days, L-Int group).
Results: Median follow-up was 35.6 months and the 3-, 5-year survival rates and median survival were 49.5%, 36.6% and 35.9 months. The duration of postoperative interval was a predictor of survival outcomes. The median survival and 5-year survival rates in S-Int, M-Int and L-Int groups were 23.6 (32.1%), 44.2 (43.3%) and 32.0 (31.5%) months (P=0.007). The difference was statistically significant between the M-Int and S-Int or L-Int group but was not between the S-Int and L-Int group. Besides, toxic reactions including early, late and adverse events (grade ≥3) in M-Int group were significantly less than S-Int and show no significant differences with L-Int group.
Conclusion: The optimal time interval was from 29 days to 56 days (5-8 weeks) both in terms of survival outcomes and toxic reactions.
Keywords: TESCC; aCRT; adjuvant chemotherapy and radiation therapy; survival; thoracic esophageal squamous cell carcinoma; time interval; toxic reactions.
© 2020 Wu et al.