Medullary carcinoma of the thyroid.

: Three patients with medullary carcinoma of the thyroid gland, one sporadic and two familial, are described. One of the patients presented at a late stage of the disease with evidence of wide dissemination and severe diarrhea, which was controlled by indomethacin. The value of venous catheterization and plasma thyrocalcitonin measurements in evaluating the extent of the disease was demonstrated in this case.