Impact of Micro- and Macroscopically Positive Surgical Margins on Survival after Resection of Adrenocortical Carcinoma

Adrenocortical carcinoma (ACC) is a rare, aggressive cancer; complete surgical resection offers the best chance for long-term survival. The impact of surgical margin status on survival is poorly understood. Our objective was to determine the association of margin status with survival. Patients with ACC were identified from the National Cancer Data Base, 1998-2012, and stratified based on surgical margin status (negative vs. microscopically positive [+] vs. macroscopically [+]). Univariate/multivariate regression/survival analyses were utilized to determine factors associated with margin status and overall survival (OS). A total of 1553 patients underwent surgery at 589 institutions: 86% had negative, 12% microscopically (+), and 2% macroscopically (+) margins. Those with microscopically (+) and macroscopically (+) margins more often received adjuvant chemotherapy (39.4% macroscopically (+) vs. 38.5% microscopically (+) vs. 25.2% negative margins, p < 0.001). For unadjusted analysis, there was a significant difference in OS between the groups (log-rank p < 0.001), with median survival times of 58 months (95% confidence interval [CI] 49-66) for those with negative margins, 22 months (95% CI 18-34) microscopically (+), and 14 months (95% CI 6-27) macroscopically (+) margins. After adjustment, both microscopically (+) (HR 1.76, p < 0.001) and macroscopically (+) (HR 2.10, p = 0.0019) margin status were associated with compromised survival. Having micro- or macroscopically (+) margin status after ACC resection is associated with dose-dependent compromised survival. These results underscore the importance of achieving negative surgical margins for optimizing long-term patient outcomes.