Abstract
We have experienced a case of ectopic ACTH syndrome due to thymic carcinoid, which is the fifth case reported in Japan. The case is a 23-year-old male, who presented the high blood pressure of 180-140 mmHg, moon face, suggillation, acne, hirsutism and a striae cutis. On laboratory findings there were hypokalemia and hyperglycemia with fasting blood sugar of 170 mg/dl, for which insulin therapy was started. The levels of urine 17-OHCS, 17-KS and plasma cortisol, ACTH, 11-OHCS, were also abnormally high, and these high hormone levels could not be inhibited even with administration of 8 mg/day of dexamethasone. Operation was performed under the diagnosis of thymoma and a mass weighing approximately 160 g was excised, but total excision was not possible because of tumor invasion to pleula and superior vena cava. However, the operation resulted in remarkable improvement of clinical symptoms and laboratory findings. That is, fasting blood sugar decreased to 72 mg/dl so that insulin was no longer necessary, blood pressure became normal and hormone levels also became normal. Histological diagnosis was thymic carcinoid, and ACTH-like immunoreactivity in the tissue showed the remarkably high value of 12000 ng/g tissue.
