Transsphenoidal selective removal of the functioning pituitary microadenomas--operative results (author's transl)

Abstract

From December 1974 to October 1977, 11 transsphenoidal microsurgical operations were performed on 11 patients with functioning pituitary microadenomas. Of these patients, 6 had symptoms of hypersecretion of human growth hormone (acromegaly with or without diabetes mellitus), and the remaining 5 showed symptoms due to hypersecretion of prolactin (galactorrhea with or without amenorrhea). Preoperatively, elevated serum HGH concentration was observed in the acromegalic patients (12-86 ng/ml), and they were responsive to intravenous TRH. Elevated serum prolactin (PRL) concentration was also observed in 3. The secretional function of other anterior pituitary hormones was normal or slightly decreased. Elevated serum PRL concentration was noticed in all of the patients with galactorrhea (200-1050 ng/ml), and they were variably responsive to intravenous TRH. The other anterior pituitary hormones were normal or slightly decreased. Neuroradiological examination revealed that each adenoma was an enclosed tumor without suprasellar extension. The sella turcica was of almost normal size, but discrete bulging of the sellar wall was seen. Anteroposterior tomograms showed unilaterally depressed sellar floor, and lateral projection revealed double contour of the sellar wall. Selective gross total removal was attempted through the transsphenoidal procedure. The adenomas were found within the pituitary gland just adjacent to the discrete bulging of the sellar floor. The size of the tumor varied from 5 to 10 mm in diameter. A small cyst was found within the adenoma tissue in 2 patients with galactorrhea, who, as others, had not undergone prior therapy. Diabetes inspidus was a postoperative hazard in 4 cases. Neither operative deaths nor complications were recorded. Postoperatively, a marked decrease of serum HGH concentration below 5 ng/ml and relief of clinical symptoms was obtained in 4 acromegalic patients. In one of the other 2 patients, because of insufficient reduction of serum HGH concentration, postoperative irradiation was given, but no responsiveness was noted. In the patients with galactorrhea, the elevated serum PRL concentration was significantly reduced immediately after the operation, and there was no further lactation. During follow-up period ranging from 1 to 34 months, regular menstration was observed in 6 out of 9 female patients, biphasic basal body temperature in 2, and pregnancy in 1 patient. In the patients who underwent removal of the microprolactinoma, there was a tendency of gradual increase of serum PRL concentration, and galactorrhea recurred in 1 patient. Ethanol fixation of the tumor bed should have been undertaken during surgery.