Tumor response and survival outcomes of salvage concurrent chemoradiotherapy with three-dimensional conformal radiotherapy and 5-fluorouracil/platinum-based chemotherapy for postoperative locoregional recurrence of esophageal squamous cell carcinoma

BACKGROUND: Salvage concurrent chemoradiotherapy is effective against locoregional recurrence after curative resection of esophageal squamous cell carcinoma. However, there is no consensus on its application. We investigated the outcomes of salvage concurrent chemoradiotherapy (60 Gy in 30 fractions) with three-dimensional conformal radiotherapy and 5-fluorouracil/platinum-based chemotherapy. METHODS: We retrospectively investigated the outcomes and prognostic factors in 51 patients with esophageal squamous cell carcinoma treated with salvage concurrent chemoradiotherapy. RESULTS: The median follow-up was 17.5 (range, 2.8–116.1) months. The overall response, complete response, and partial response rates were 74.5%, 49.0%, and 25.5%, respectively. The median progression-free survival was 8.2 months; the 3-year progression-free survival rate was 22.9%. The median overall survival was 23.1 months; the 3-year overall survival rate was 40.7%. Overall survival was significantly longer in patients with a complete response than in those without (median overall survival: not reached vs. 15.3 months); 3-year overall survival rate: 62.5% vs. 20.3% (hazard ratio: 0.222; P < 0.001). Multivariate analysis showed that the independent prognostic factor for overall survival was < 25 mm longest diameter of metastatic lymph nodes (hazard ratio: 3.71). CONCLUSIONS: Salvage concurrent chemoradiotherapy (60 Gy in 30 fractions) with three-dimensional conformal radiotherapy and 5-fluorouracil/platinum-based chemotherapy was an effective and safe treatment for locoregional recurrence after curative resection of esophageal squamous cell carcinoma, especially in those approaching a complete response. Additionally, a shorter longest diameter of metastatic lymph nodes may be associated with better long-term survival. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10388-022-00936-3.