[Early recognition of C-cell carcinoma by family screening (author's transl)].

All available family members of five patients with C-cell carcinoma (medullary carcinoma of the thyroid) were tested for their basal serum-calcitonin level and after pentagastrin stimulation. In two females, aged 12 and 25 years, from two different families, serum-calcitonin was elevated, but only after repeated tests or after pentagastrin stimulation, to definitely abnormal levels. Neither had palpable thyroid nodules, lymph-adenopathy or diarrhoea. The thyroid scan was normal and there were no storage defects. But because of the family history and the elevated serum-calcitonin levels total thyroidectomy was performed in both. The specimens revealed multicentric, bilateral C-cell carcinomas. The serum-calcitonin concentration became completely normal postoperatively, so that one may justifiably speak of a curative effect of the thyroidectomy in these two instances of early diagnosis.