The Predictors and Clinical Impact of Positive Resection Margins on Frozen Section in Gastric Cancer Surgery

Purpose: The aim of this study is to compare the characteristics of tumor and prognosis, depending on the status of resection margin involvement, on the frozen section diagnosis in gastric cancer. Materials and Methods: This study was conducted retrospectively, in 83 margin-positive patients on the frozen section diagnosis, who underwent gastrectomy from July 1995 to September 2006. The control group was selected by matching the age, gender, TNM stage and status of adjuvant chemoradiotherapy, among those who had shown clear resection margins. The characteristics of tumor and patient survival are investigated, and they were analyzed between the two groups. Results: The tumor size was significantly larger in the study group than that of the control group (P=0.037). There was significant difference between the two groups in location of the tumors (P=0.003). Multivariate analysis indicated that only the location and Lauren's classification are independent factors, which affected the resection margin involvement. Median survival was $41.0{\pm}11.5$ months in the study group and $93.0{\pm}30.3$ months in the control group (P=0.049). In the survival analysis, it was investigated that TNM stage and the resection margin involvement of the frozen section diagnosis were the critical variables. Conclusions: When the tumor is located at the middle or the upper third, or the Lauren's indeterminate type, they are highly likely to show the resection margin involvement on the frozen section diagnosis, and it can, therefore, have negative effects on the prognosis. It is considered as good to perform more extensive resection as possible, during the initial resection.