Patterns of recurrence after oesophagectomy and postoperative chemoradiotherapy versus surgery alone for oesophageal squamous cell carcinoma

Background: Patterns of recurrence after surgery with postoperative chemoradiotherapy (S-CCRT) or surgery alone in patients with oesophageal squamous cell carcinoma (SCC) may differ. This might influence the nature and timing of subsequent management strategies. Methods: Patients with SCC who had undergone R0 resection were included. Propensity score matching was used to select matched groups. Survival and recurrence were compared by Kaplan–Meier analysis. Univariable and multivariable Cox regression analyses were used to identify prognostic factors for overall and disease-free survival. Results: A total of 1390 patients were included, of whom 1000 had surgery alone and 390 underwent S-CCRT. Propensity score matching yielded 213 well balanced pairs. The 3-year overall survival rate and median survival time in the S-CCRT group were 0·50 and 36·5 (95 per cent c.i. 25·1 to 52·6) months respectively, compared with 0·38 and 22·8 (18·2 to 29·0) months in the surgery-alone group (P = 0·006). The 3-year disease-free survival rate and median disease-free survival time in the S-CCRT group were 0·46 and 30·6 (22·2 to 39·3) months respectively, compared with 0·36 and 17·6 (11·3 to 23·9) months in the surgery-alone group (P = 0·006). The 2-year freedom from locoregional recurrence rate was 0·87 and 0·77 in the S-CCRT and surgery-alone groups respectively (P = 0·003). In multivariable analysis, independent prognostic factors for disease-free survival included age over 56 years, pT3–4 category, pN category, poor differentiation, tumour length exceeding 4·0 cm, and receiving postoperative chemoradiotherapy (hazard ratio 0·62, 95 per cent c.i. 0·47 to 0·81; P < 0·001). Conclusion: Oesophagectomy with postoperative chemoradiotherapy was associated with longer survival and lower recurrence rates, especially at a locoregional level, compared with surgery alone.