Prognostic Factors of Adrenocortical Carcinoma: An Analysis of the Surveillance Epidemiology and End Results (SEER) Database

Objective: To define the prognostic factors associated with overall survival (OS) and cancer-specific survival (CSS) for adrenocortical carcinoma (ACC). Patients and Methods: We used the Surveillance, Epidemiology and End Results (SEER) database (1973-2014) to identify ACC patients. Correlated variables, including age, sex, race, tumor laterality, marital status at diagnosis, treatment of primary site, lymph node dissection, radiation therapy, chemotherapy, tumor size and tumor stage, were extracted. Univariate and multivariate Cox regression were used to define the prognostic factors. Harrell's concordance index (C index) was calculated to evaluate the discrimination ability for the prognostic predictive models. Results: There were 749 ACC patients identified from the database. The overall median survival time was 22 (95%CI, 18-25) months. In multivariate analysis, age, treatment, chemotherapy and tumor stage were independent risk factors for both overall and cancer-specific survival. Tumor stage had a dominant effect on the cancer prognosis. Additionally, the ENSAT stage had better discrimination than the AJCC stage group in different predictive models. Conclusion: Our study shows that age, treatment of primary site, chemotherapy and tumor stage were prognostic factors for overall and cancer-specific mortality in ACC patients. Among these factors, tumor stage had a dominant effect. The ENSAT stage was more discriminative than the 7th AJCC stage group. Further multi-center prospective validation is still needed to confirm these outcomes.