Survival outcomes of neoadjuvant and adjuvant chemoradiotherapy for locally advanced adenocarcinoma of the oesophagogastric junction: a retrospective cohort study using the SEER database.

BACKGROUND

Both neoadjuvant chemoradiotherapy (nCRT) and adjuvant chemoradiotherapy (aCRT) have survival advantages over surgery alone in patients with adenocarcinoma of the oesophagogastric junction (AEG). However, whether there is a difference in the survival benefit between these two treatments and who can benefit from them remains controversial, and there are currently no randomised controlled trials to address these issues. This study compared the survival outcomes of patients with locally advanced AEG receiving nCRT and aCRT.

METHODS

The data of patients with locally advanced AEG were collected from the Surveillance, Epidemiology, and End Results (SEER) database (2004-2015). Patients in the nCRT and aCRT groups were propensity-score matched 1:1, and the Kaplan-Meier method and log-rank test were used for survival analysis between the two groups. Univariable and multivariable Cox regression models were performed to identify the prognostic factors.

RESULTS

Of the 1,436 cases diagnosed as locally advanced AEG, we included 442 in the final analysis. The median overall survival (OS) of the nCRT and aCRT cohorts were 30.0 and 25.0 months, respectively (P=0.042), and the median tumour specific survival times were 37.0 and 31.0 months, respectively (P=0.249). Multivariable Cox regression analysis showed that OS was independently related to age [<60 years ≥70 years, hazard ratio (HR) =0.619, 95% CI: 0.510-0.751, P<0.001; 60-69 years ≥70 years, HR =0.661, 95% CI: 0.536-0.814, P<0.001] and N stage (N2 N1, HR =1.213, 95% CI: 1.002-1.468, P=0.048; N3 N1, HR =1.606, 95% CI: 1.190-2.167, P=0.002). Through stratifying patients by TNM stage, stage IIIB, and N1 stage, we observed that patients receiving nCRT had a better prognosis.

CONCLUSIONS

Patients receiving nCRT had significantly better survival than those receiving aCRT. nCRT may offer some therapeutic benefits in patients with IIIB stage AEG.