Relapse of the pituitary adenoma with a change of its hormonal activity in a female patient with multiple endocrine neoplasia syndrome type 1

Multiple endocrine neoplasia syndrome type 1 (MEN1, Wermer's syndrome) is a group of heterogeneous inherited diseases, with its pathogenesis related to hyperplasia or neoplasms of several endocrine glands. This syndrome is characterized by autosomal dominant mode of inheritance, high penetrance and similar prevalence among males and females. Prevalence of MEN1 is estimated to be 1:100,000 of the population. An interesting feature of the presented clinical case is a relapse and transformation of pituitary tumor from a prolactin-secreting into the mixed one, with distinct compartments of ACTH- and prolactin-secreting, in a female patient with a family MEN1 syndrome, with involvement of the pancreas, parathyroid and pituitary glands. Her brother had a synchronous manifestation of the same types of tumors, except corticotropinoma. The presented clinical case highlights the necessity of a comprehensive and life-long follow-up of MEN1 patients for a timely detection of neoplasms and appropriate treatment.