Supraclavicular node metastasis in thoracic esophageal squamous cell carcinoma

Background Supraclavicular node metastasis is common in patients with esophageal cancer. However, considerable controversy remains regarding whether the supraclavicular node metastasis means regional node or distant metastasis. This research investigated the frequency of supraclavicular node metastasis in patients with esophageal squamous cell carcinoma (ESCC), identified the factors correlated with supraclavicular node metastasis, and evaluated the clinical relevance of supraclavicular node metastasis in thoracic ESCC. Methods We retrospectively analyzed the clinical data of 276 consecutive patients with thoracic ESCC who underwent esophagectomy with three-field lymph node dissection in the First Affiliated Hospital of Zhengzhou University from January 2000 to December 2008. Results The frequency of supraclavicular node metastasis was 26.1 %. Correlation analysis showed that higher tumor location, longer tumor length, higher pathologic T stage, and lower histologic grade were associated with a higher frequency of supraclavicular node metastasis (all p < 0.05). Patients with solitary supraclavicular node metastasis had a significantly lower 5-year cumulative survival rate than those with solitary cervical paraesophageal node metastasis (26.9 vs 50.3 %, p < 0.05). Conclusions Higher tumor location, longer tumor length, higher pathologic T stage, and lower histologic grade are associated with a higher frequency of supraclavicular node metastasis. Supraclavicular node metastasis indicates a worse prognosis for patients with thoracic ESCC compared with cervical paraesophageal node metastasis, and it should be classified as M1.