Endocrine Abstracts

Introduction: MUTYH (MutY homolog Escherichia coli, homolog of MYH, hMYH) is a repair enzyme with a crucial role in the correction of DNA errors, being considered a protective factor of the cell. MUTYH mutations have been linked to MUTYH-associated polyposis syndrome (MAP), an autosomal recessive disorder characterized by multiple colorectal adenomas. Patients with MAP show a much higher lifetime risk of gastrointestinal cancers as an additional role of MUTYH, it appears to contribute in the involvement of pathologies based on oxidative stress damage, as well as in the prevention of inflammatory and degenerative based disorders. Although the development of extraintestinal pathology is not fully defined, it seems to increase the risk of tumors and endocrinological pathology.

Materials and methods: Prospective study, selecting 27 living patients diagnosed and registered with MUTYH syndrome under follow-up from the Digestive Department of the Hospital Universitario de Navarra (HUN) with current or past follow-up in the Endocrinology Department. Radiological tests, clinical, and analytical variables were analyzed.

Results: The study population included 14 men (51.8%) and 13 women (48.2%), with a mean age of 56 years. The median age at diagnosis of FAP was 48 years, with a mean follow-up time of 8 years. All patients had an abdominal imaging study (CT or MRI), detecting lesions in 3/27 (11.11%). The average size was 2 cm. One of the patients had bilateral adenomas, while the other two were unilateral. Of note, one of them showed calcifications in both glands in the CT scan. All were incidental findings presented as non-functioning adenomas in the analytical tests performed. The study consisted of the overnight 1 mg dexamethasone suppression test, catecholamine/metanephrine determination, adrenal androgen production, and if appropriate, screening of primary hyperaldosteronism. No major endocrinological alterations (defined as nodular disease or thyroid carcinoma, thyroid autoimmunity, diabetes, obesity) were detected when comparing both groups. There were also no differences in gender, age, or time since diagnosis.

Conclusions: Adrenal lesions are common in patients with MUTYH who undergo abdominal imaging. They appear to follow a benign and slowly progressive course, presenting clinically and analytically as non-functioning lesions.