[Lump in the neck: 4 patients with a medullary thyroid carcinoma].

In a 25-year-old man, medullary thyroid carcinoma (probably a solitary sporadic form) was diagnosed following investigation of a small lump in the patient's neck. This was removed and followed up with further treatment. In a 27-year-old man, episodes of headache, palpitations and excessive perspiration (due to a pheochromocytoma) and a positive family history of thyroid problems led to further investigations and the subsequent diagnosis of multiple endocrine neoplasia (MEN) type 2A. The patient died at 48 years of age as the result of liver metastases. A total thyroidectomy had been carried out on a 19-year-old man with familial medullary thyroid carcinoma. The calcitonin levels remained elevated, but no tumour residues could be found. A 16-year-old girl with MEN type 2B had also previously undergone surgery. Her main complaint consisted of persistent constipation. Thyroid carcinomas usually present as a nodule in the neck. In 25% of cases, medullary thyroid carcinoma is part of the MEN2 syndrome. The clinical approach for medullary thyroid carcinoma is based on pathological findings following fine needle aspiration biopsy. The results of DNA tests determine the course of treatment and the need for family testing. In families with a hereditary form, there is a clear genotype-phenotype correlation. Early diagnosis and treatment can improve life expectancy.