Prognostic Factors in Advanced Adrenocortical Carcinoma: Summary of a National Referral Center's 20 years of Experience

Context: Adrenocortical carcinoma (ACC) is a rare malignancy with poor prognosis for both locally advanced and metastatic disease. Standard treatment with combination etoposide-doxorubicin-cisplatin-mitotane (EDP-M) is highly toxic and some patients benefit from mitotane monotherapy. However, identification of these patients remains challenging. Objective: We present a summary of the Israeli national referral center's 20 years of experience in treating advanced ACC, with the aim of identifying prognostic factors and assisting in treatment decision making. Methods: We conducted a retrospective multivariate analysis of patients treated for metastatic or locally advanced ACC at Hadassah Medical Center between 2000 and 2020 to determine clinical, pathological, and treatment factors correlated with overall survival (OS). Results: In our cohort of 37 patients, a combination of modified European Network for the study of Adrenal Tumors (mENSAT) staging with either grade and R status, or age and symptoms was validated to stratify prognosis (P = .01 and P = .03, respectively). Patients who underwent R0 resection followed by radiotherapy or metastasectomy for oligometastatic disease had longer OS than patients with residual disease: median OS of 55 months vs 14 months, respectively, hazard ratio 3.1 (CI 1.4-6.7, P = .005). Patients treated with mitotane monotherapy had a significantly better prognosis, yet this result was attenuated in a multivariate analysis controlling for mENSAT and R status. Of patients treated with EDP-M, 41.4% experienced grade 3 or higher adverse events. Conclusion: Patients with advanced ACC achieving R0 status have a better prognosis and might benefit from mitotane monotherapy.