Tubulopapillary adrenocortical adenoma in a patient with familial adenomatous polyposis: a morphologic, ultrastructural, and molecular study

• Published in: Human pathology Vol. 87; pp. 51 - 56
• Main Authors: Huang, Huiya, Chang, Jason, Rosati, Stefano, Geurts, Jennifer, Mackinnon, A. Craig
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.2019; Elsevier Limited
• Subjects: Adrenal glands; Adrenocortical adenoma; APC gene; Colorectal cancer; Deoxyribonucleic acid; DNA; Familial adenomatous polyposis; Genetic disorders; Genetic testing; Localization; Morphology; Mutation; Neuroendocrine tumors; Patients; Polyps; Stains & staining; Tubulopapillary adenoma; Tumors; Tubulopapillary adenoma; Adrenocortical adenoma; Familial adenomatous polyposis; APC gene
• ISSN: 0046-8177; 1532-8392
• DOI: 10.1016/j.humpath.2018.08.022

Patients with familial adenomatous polyposis have a higher incidence for developing adrenal neoplasms, most of which are nonfunctioning with conventional histologic appearance. We report a patient with a history of multiple colon polyps who developed an adrenocortical adenoma with unusual morphology. The tumor showed a tubulopapillary architecture and plasmacytoid cytomorphology that were distinct from conventional adrenocortical adenomas. β-Catenin stain showed aberrant nuclear positivity in the tumor, suggesting an altered β-catenin–related pathway. The unusual morphology prompted molecular characterization, and sequencing demonstrated the patient to be germline heterozygous for a 5-base-pair APC deletion at codon 1309 with loss of heterozygosity in the tumor. Our study provides further evidence of genetic predisposition to extraintestinal tumors in the familial adenomatous polyposis population. •This case describes the highly unusual finding of an adrenocortical adenoma with distinct histology in a familial adenomatous polyposis (FAP) patient, which has been seldom reported in the literature.•The tumor demonstrates a unique tubulopapillary and plasmacytoid histologic appearance with β-catenin nuclear translocation.•The case also demonstrates the importance of careful histologic assessment for prompting a molecular workup for hereditary changes in the APC gene.•This is the first report of APC codon 1309 variant associated with the development of adrenal cortical adenoma found in an FAP patient.•Our report provides further evidence that germline APC mutations contribute to higher incidence of extraintestinal tumors in FAP patients.