Manifestation, management and outcome of subclinical pituitary adenoma apoplexy

The objective of this study was to investigate the clinical features, diagnosis, treatment and outcomes of subclinical pituitary adenoma apoplexy (SPAA) in 185 consecutive patients between January 1990 and May 2007. Of the 185 patients, 133 (71.89%) underwent transsphenoidal tumor decompression and the remaining 52 patients (28.11%) underwent transcranial surgery. Preoperative and postoperative endocrinological hormone concentrations were measured in all patients. Pituitary imaging was obtained by CT scans or MRI. Follow-up outcomes were obtained from the records of outpatient visits and by telephone interviews. Visual disturbance, headache and pituitary function impairment improved significantly in all patients. Prolactinoma was the most frequent type of pituitary adenoma in our series (51.89%). SPAA usually occurred in patients with large or giant adenomas (85.95%). Postoperative follow-up ranged from 1 year to 17 years with a mean of 7.4+/-1.6 years. The tumor recurred in 23 patients, 18 of whom were treated with postoperative radiotherapy for either residual tumors (n=8) or recurrence (n=10). Long-term thyroid hormone replacement was necessary in eight patients and steroid hormone replacement in six patients. The incidence of SPAA is relatively high compared with that of acute pituitary apoplexy. The exact pathogenic mechanism of SPAA remains unknown. MRI is significantly better than CT scans for detection of SPAA. Transsphenoidal decompression is safe and effective. Surgical decompression should be performed as early as possible.