Influence of neoadjuvant chemoradiation on the number and size of analyzed lymph nodes in esophageal cancer.

BACKGROUND: Studies have shown that along with primary tumor response, lymph node status after RTx/CTx is one of the most important prognostic factors for advanced esophageal carcinoma. The goal of our study was to investigate the influence of neoadjuvant radiochemotherapy (RTx/CTx) on lymph nodes (LN). MATERIALS AND METHODS: From 1997 until 2006, 297 patients underwent surgery for advanced esophageal carcinoma. Of these, 192 received preoperative chemoradiation (5-FU, cisplatin, 36 Gy). The following matched subgroups were chosen: Group I, 20 with surgery alone: 10 adenocarcinoma (AC), 10 squamous cell carcinoma (SCC); Group II, 20 with minor response (10 AC, 10 SCC); Group III, 20 with major response (10 AC, 10 SCC). Tumor response was graded as "minor" or "major" according to the Cologne Regression Scale, the LN size determined by the largest measured diameter. RESULTS: A total of 1967 LNs from 60 patients were examined. Of these, 161 LNs showed metastasis. The median number of LNs examined per patient was not significantly higher in group I compared with the group with pretreatment (32 vs 31). Group I and group II showed LN metastasis (LNM) in 65% of cases, and group III in only 20% (p = 0.011). LNMs after pretreatment had significantly smaller median diameters (5.0 mm) than those without (7.0 mm) (p < 0.02). Nonmetastatic LN size did not vary between the three groups. LN size with and without metastasis did not differ between AC and SCC or between major and minor responders. CONCLUSION: With good response to neoadjuvant radiochemotherapy, the size and the number of metastatic LNs is significantly reduced regardless of histologic cancer type.