Analysis of definitive chemo-radiotherapy for esophageal cancer with supra-clavicular node metastasis based on CT in a single institutional retrospective study: a propensity score matching analysis

BACKGROUND: The prognostic value of supra-clavicular lymph node (SCLN) metastases in esophageal cancer (EC) is still not clear. METHOD: From January 2009 to December 2015, a survival analysis was performed to retrospectively identify the prognostic value of SCLN metastasis on survival on 751 patients with EC treated with definitive chemo-radiotherapy (dCRT). RESULTS: The median follow-up duration for living patients was 56.6 months. The median overall survival (OS) for all patients was 16.6 months. Patients with SCLN metastasis had a much poorer prognosis for OS (χ(2) = 17.342, P < 0.001), distant metastasis-free survival (DMFS) (χ(2) = 24.793, P < 0.001) and progression-free survival (PFS) (χ(2) = 25.802, P < 0.001) than those without SCLN metastasis. The same results were found after propensity score matching. Nonetheless, the prognosis of patients with cervical or upper thoracic EC metastasis in SCLN was better than those of patients with middle or lower thoracic EC metastasis in SCLN for OS (χ(2) = 4.516, P = 0.038), DMFS (χ(2) = 8.326, P = 0.004) and PFS (χ(2) = 6.255, P = 0.012). Univariate analysis showed that gender, middle or lower thoracic EC with SCLN metastasis, tumor length, tumor diameter, concurrent chemo-radiotherapy (CCR) and number of lymph nodes were prognostic factors for PFS. Gender, age, middle or lower thoracic EC with SCLN metastasis, tumor diameter, tumor length, and number of lymph nodes were prognostic factors for DMFS. According to the multivariate analysis, only middle or lower thoracic EC with SCLN metastasis and number of lymph nodes were independent prognostic factors for DMFS and PFS. CONCLUSION: For patients with cervical or upper thoracic EC, metastasis in SCLN should be considered to be regional lymph nodes and treated with curative intent if the total number of lymph nodes is limited. However, for patients with middle or lower thoracic EC, metastasis should be considered to be a higher level N stage or M1 stage, and it is thus necessary to provide consolidation chemotherapy after dCRT.