[Adrenal cortical carcinoma in children: a clinicopathological analysis of 25 cases]

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of adrenal cortical carcinoma (ACC) in children. Methods: Twenty-five children with ACC diagnosed in the Department of Pathology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China from March 2014 to August 2022 were retrospectively analyzed. The related literature was reviewed. Results: A total of 25 children with ACC were collected, including 11 males and 14 females, with a male to female ratio of 1.0∶1.3. The patient ages ranged from 8 months to 14 years (median, 4 years). Eighteen cases with clinical data had functional tumors (18/22, 81.8%) presenting with virilization or precocious puberty (15/18), symptoms related to hypercortisolism (8/18) or endocrine symptoms mixed with both (5/18), while 3 cases (3/22, 13.6%) had unknown clinical data. The clinical manifestations of four patients with nonfunctional tumors were an abdominal mass and/or abdominal pain, walking instability and others. Grossly, the average maximum diameter of the tumor was 9.4 cm. Most of the tumors were nodular and partially encapsuled. The cut surfaces were gray or gray brown, soft with hemorrhage. Histologically, the tumor cells were diffusely distributed, separated by a vascular-rich network. The tumor cells were large, with distinct nucleoli, abundant eosinophilic or clear cytoplasm, and round or oval nuclei. The mitotic index was high, and atypical mitoses were common. Necrosis, calcification, capsule invasion or/and venous invasion were present. In some cases, the tumor invaded the surrounding soft tissues or kidneys. Immunohistochemically, the tumor cells were diffusely positive for syn and SF1 and focally positive for α-inhibin, Melan A and Calretinin, but negative for CgA. Ki-67 proliferation index ranged from 2%-90%. TP53 gene status was examined in 7 cases, in which mutations were detected in 4 cases. Follow-up data was obtained in 21 patients, among whom 18 received chemotherapy and 3 received radiotherapy. Distant metastasis occurred in 13 patients. Median progression-free survival (PFS) was 11.2 months and median overall survival (OS) was 54.7 months. Patients aged less than 5 years had a better prognosis for OS (P<0.05) than the older ones (≥5 years), but a similar PFS (P>0.05). Male patients and Ki-67 proliferation index <15% had a better prognosis tendency for OS, but there was no statistically significant difference (P>0.05). Conclusions: ACC in children is a rare, often functional tumor associated with Li-Fraumeni genetic syndrome and has a poor prognosis. Diagnosis and differential diagnosis require a combination of morphological, phenotypic and clinical analysis.