[Multiple endocrine neoplasia (MEN)].

CLINICAL ISSUE: Multiple endocrine neoplasia (MEN) types 1 and 2 are hereditary cancer syndromes. They are characterized by the occurrence of many benign and malignant tumor types.

STANDARD TREATMENT: Carriers of a MEN1 or RET gene mutation can be identified before manifestation of the disease. Family screening allows the early diagnosis and therapy of gene carriers.

TREATMENT INNOVATIONS: Early thyroidectomy in young patients with MEN2 results in a high cure rate of medullary thyroid carcinoma (MTC). Treatment with tyrosine kinase inhibitors (TKI), such as vadetanib and cabozantinib, represents an important new therapeutic option for patients with progressive metastatic MTC. Neuroendocrine tumors (MEN1) are treated surgically and progressive disease is treated with somatostatin or everolimus.

DIAGNOSTICS: The most important imaging methods for monitoring of MTC are sonography of the neck and upper abdomen and computed tomography (CT) of the lungs. In cases of MEN1 metastases can be localized by DOTATOC positron emission tomography CT (PET/CT).

PERFORMANCE: Using these methods up to 70 % of tumors and metastases can be detected, depending on the localization, size and endocrine activity. Follow-up investigations with CT is an important tool for monitoring changes in tumor mass which are important criteria for decisions concerning TKI therapy.

ACHIEVEMENTS: Together with the doubling time of tumor markers, tumor progression monitored by imaging methods or response evaluation criteria In solid tumors (RECIST) are prognostic factors and provide indications for initiating systemic therapy (e.g.

TKI) PRACTICAL RECOMMENDATIONS: Patients with MEN syndromes should be treated in specialized centers because of the complexity and rarity.