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

PURPOSE: 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.

METHODS: 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).

RESULTS: 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.

CONCLUSIONS: 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.