Definitive radiotherapy dose escalation with chemotherapy for treating non-metastatic oesophageal cancer

The locoregional failure rate remains high after concurrent chemoradiotherapy with standard-dose radiotherapy (RT, 50–50.4 Gy) for oesophageal cancer (EC). This retrospective study evaluated whether RT dose escalation was effective among 115 consecutive patients with non-metastatic EC (July 2003 to November 2016). Forty-four patients received an RT dose of <66 Gy and 71 patients received ≥66 Gy, with most patients receiving concurrent cisplatin plus fluorouracil. The median follow-up was 12 months for all patients (52 months for 18 surviving patients). The ≥66 Gy group had significantly higher 3-year rates of overall survival (17.9% vs. 32.1%, p = 0.026) and local progression-free survival (46.1% vs. 72.1%, p = 0.005), but not disease progression-free survival (11.4% vs. 21.9%, p = 0.059) and distant metastasis-free survival (49% vs. 52.6%, p = 0.852). The ≥66 Gy group also had significantly better 5-year overall survival compared with 41.4–65.9 Gy. The only significant difference in treatment-related toxicities involved acute dermatitis (7% vs. 28%, p = 0.009). Inferior overall survival was associated with poor performance status, clinical N2–3 stage and not receiving maintenance chemotherapy. In conclusion, patients with inoperable EC experienced better survival outcomes and acceptable toxicities if they received higher dose RT (≥66 Gy) rather than lower dose RT (<66 Gy).