A Case of Multiple Endocrine Neoplasia Type II b: Endocrinological Evaluation and Family Screening

The case of a 27 year-old woman with typical manifestations of multiple endocrine neoplasia type II b is reported. Medullary carcinoma of the thyroid was detected on the occasion of an operation for goiter when she was 22years of age. Constipation due to megacolon caused by intestinal neuroma had persisted since childhood. Neuroma of the tongue and lips, hypertrophic corneal nerve and Marfanoid habitus were also found. The presence of pheochromocytoma was suggested in view of the positive cold pressor and results of glucagon loading tests, but this remains inconclusive. There was prolonged and exaggerated response of growth hormone and luteinizing hormone after provocative tests for anterior pituitary gland, in spite of normal basal levels. Screening of her family members for medullary carcinoma of the thyroid was carried out by measurement of immunoreactive calcitonin. Two siblings were shown to be hypercalcitoninemic, presumably due to occult medullary carcinoma of the thyroid. This case appeared to be the first in Japan showing multiple endocrine neoplasia type II b accompanied by familial hypercalcitoninemia.