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The role of circumferential resection margin in esophageal cancer: Does it influence local recurrence and survival?

23 Background: Established independent prognostic factors after resection are tumor stage, tumor grade, nodal involvement, lymph node ratio and tumor infiltration of the proximal or distal resection margin in esophageal cancer. In a few series the clinical and prognostic significance of the CRM involvement have been investigated, showing conflicting results in esophageal cancer. The purpose of this study was to analyze the significance of microscopic tumor involvement of the CRM on long-term survival and local recurrence (LR) following esophagectomy in T3 esophageal cancer.


METHODS
Between 1993 and 2008, 146 patients, with T3 esophageal tumors had undergone potentially curative transthoracic esophagectomy (TTE) with radical lymphadenectomy of the upper abdomen and mediastinum or transhiatal esophagectomy (THE) with microscopically tumor free proximal and distal resection margins. Surgical specimen were recorded as CRM positive (CRM+) if the distance from the CRM was measured microscopically 1mm or less; otherwise it was graded as CRM negative (CRM-). None of these patients had a neoadjuvant therapy.


RESULTS
In the whole study population, median survival for CRM-- and CRM+ patients was 13 and 15 months, respectively (p=.933). LR occurred in 48 patients (32.9%). Of these, 19 (39.6%) had a positive CRM and 29 patients (60.4%) a negative CRM. Of the remaining 98 patients (67.1%) without LR, in 40 patients (40.8%) CRM was positive, while 58 patients (59.2%) had a negative CRM (p=.887). The grading and tumor localization had no significant influence on the LR (p=.181 and .163). The TTE group included 104 patients, in 68 patients (65.4%) of them CRM was negative, in 36 (34.6%) CRM was positive. The THE group included 42 patients, in 19 patients (45.2%) CRM was negative, whereas in 23 patients (54.8%) CRM was positive, respectively (p=.025). CRM involvement had no statistical significant impact on LR or metastatic relapse in either node negative tumors (p=.384) or node positive tumors (p=.653).


CONCLUSIONS
After TTE a positive CRM was less seen without statistifical influence on median survival time. This study has shown that the presence of microscopic tumor of the CRM is not a significant prognostic variable.