Weineke criteria, Ki-67 index and p53 status to study pediatric adrenocortical tumors: Is there a correlation?

Purpose: Adrenocortical tumors (ACTs) are rare in pediatric age group. Pediatric ACTs behave differently from their histologically similar adult counterparts and Weiss criteria often cannot accurately predict their clinical behavior. Wieneke et al. proposed a set of 9 macroscopic and microscopic criteria for diagnosis of malignancy in pediatric ACTs. The aim of the present study was to validate the Wieneke criteria in pediatric ACTs and to correlate Ki-67 labeling index and p53 expression with the Wieneke score.

Methods: Our study comprised 17 cases of pediatric ACTs more than 11years, from January 2005 to December 2015. Relevant clinical features were obtained from records. Comprehensive analysis of gross and microscopic features was performed, according to the criteria proposed by Wieneke et al. Each tumor was categorized as benign, intermediate for malignancy or malignant. Ki-67 and p53 immunostaining was done in all cases. The patients were followed-up over a period of 6months to 60months.

Results: Applying Wieneke criteria, there were 9 benign and 7 malignant cases, and 1 case was assigned as intermediate for malignancy. The most significant markers in favor of malignancy were capsular and venous invasion, followed by the presence of mitotic figures >15/20 HPF. p53 was over-expressed in 86% of the carcinomas. We found a significant correlation between Ki-67 index and Wieneke scoring system. All cases of adenoma achieved complete remission, while 3 patients with carcinoma died.

Conclusion: Our study validates the utility of Wieneke criteria in differentiating adrenocortical carcinomas from adenomas in pediatric age group. Moreover, Ki-67 index and p53 status can be used as supplementary tools in distinguishing adrenocortical carcinomas from adenomas.