To found a score system to estimate operation difficulty and surgical complexity of adrenal tumors.

A retrospective single-center analysis was made in 466 patierts with adrenal tumors who underwent retroperitoneal laparoscopic surgery by the same surgeon. The adrenal tumor score system (ATS) was based on the quantization of the following independent variables: size of the tumors, boundary with surrounding organs, boundary with abdominal great vessels, endocrine function and body mass index, which were associated with operation time and the amount of bleeding after screening, and a clinical validation was performed for the score system.

By univariate and multivariate Logistic regression analysis in 466 cases of adrenal tumor, size of the tumors, boundary with surrounding organs, boundary with abdominal great vessels, endocrine function and body mass index were all associated with operation time and the amount of bleeding (P<0.01). A correlation existed between ATS and operation time, blood loss during operation (P<0.01). And there were significant differences among high, moderate and low complexity groups.

ATS system covering all the major factors that influence operation difficulty and surgical complexity of adrenal tumors, has important clinical value of surgical treatment.