Benign adrenocortical tumor exhibiting high p53 positivity via immunohistochemistry diagnosed as Li-Fraumeni syndrome

Abstract

A 22-month-old boy presented with penile enlargement and pubic hair growth. Blood tests and contrast-enhanced abdominal computed tomography revealed an androgen-producing tumor in the left adrenal gland, which was resected laparoscopically. Based on the Wienecke criteria, the pathological diagnosis was benign adrenocortical tumor. However, p53-immunohistochemistry showed >90% positive cells, which is atypical for adenomas. At 20-month follow-up without adjuvant therapy, testosterone levels were below detection threshold, with no signs of recurrence on imaging. Genetic testing revealed a pathogenic heterozygous germline TP53 variant (c.733G>A, p.Gly245Ser), confirming Li-Fraumeni syndrome. Distinguishing benign from malignant tumors is more challenging in pediatric adrenal cortex tumors than in other organs. In atypical cases, malignancy and genetic testing should be considered.