[Thyroid cancer with amyloid stroma. Results of a familial study].

We have recently studied a kindred in which there have been 2 proven and 2 probable cases of medullary thyroid carcinoma without pheochromocytoma, hyperparathyroidism or Cushing's disease. Four other members suffered from intestinal occlusion and death occurred in three of them. The family has been traced through 4 generations (80 members) and 47 members could be examined; circulating calcitonin and carcinoembryonic antigen levels were measured. This study leads to two conclusions: 1) Medullary thyroid carcinoma is transmitted as an autosomal dominant trait with a high degree of penetrance. 2) Carcinoembryonic antigen is a valuable tumour marker particularly if no calcitonin radioimmunoassay is avialable for the diagnosis of M.C.T.