Esophageal cancerThe pattern of cervical lymph node metastasis in thoracic esophageal squamous cell carcinoma may affect the target decision for definitive radiotherapy

BackgroundMetastasis to lymph nodes is a key determinant of thoracic esophageal squamous cell carcinoma (TE-SCC) prognosis. We sought to identify factors linked with cervical lymph node metastasis, which could be used to inform the decision of surgical and definitive radiotherapy.MethodsWe retrospectively reviewed records from 1715 patients who had had radical esophagectomy with three-field lymphadenectomy between January 1993 and March 2007 in our hospital. All patients included in the study had pathologically confirmed TE-SCC and no clinical evidence of cervical metastasis.ResultsCervical node metastases were found in 547 patients (31.9%); rates of cervical-node positivity were 44.2% for those with upper-thoracic tumors, 31.5% for mid-thoracic tumors, and 14.4% for lower-thoracic tumors. Univariate analysis showed that cervical node metastasis was associated with tumor site, differentiation, and length, pathologic T status, and pN status (P < 0.05); however, only tumor site and pN status retained significance in multivariate analysis (P < 0.05). Positive cervical nodes were most often found in the paraesophageal region (72.3%), followed by supraclavicular (24.4%); involvement of deep cervical (2.4%) or retropharyngeal nodes (0.9%) was rare (P < 0.0001). Positive cervical nodes were most often associated with upper TE-SCCs (60.1%), followed by middle TE-SCCs (31.2%) and lower TE-SCCs (10.6%).ConclusionsUpper TE-SCC with multiple involved nodes at any site was associated with a high rate of cervical node metastasis. These findings provide critical information for clinical decision-making regarding the extent of nodal dissection or the size of radiation fields in definitive radiotherapy.