Executive functions recover earlier than episodic memory after microsurgical transsphenoidal resection of pituitary tumors in adult patients--a longitudinal study.

Pituitary tumors may lead to cognitive dysfunction, and the most prevalent deficits are impaired memory and attention. To investigate whether memory and executive functions improve after surgical treatment we performed a prospective longitudinal study comprising 106 patients with pituitary tumors. Psychometric evaluation was performed with the d2-Letter Cancellation test, the Trail Making test, the Digit Span test and the Intelligence Structure test-Verbal Memory test at three timepoints: preoperatively, and at 3 months and 12 months after surgery. The preoperative and postoperative maximum suprasellar tumor extension and hormone status was assessed in all participants. The main finding was that concentration, working memory, and attentional speed improved significantly within the first 3 months after surgery (p<0.05), while improvement of episodic memory was not observed until 12 months after surgery (p<0.001). In the patients harbouring non-functioning adenomas, prolactinomas or other sellar lesions, the most important factor promoting improvement of neurocognitive function was the removal of the suprasellar tumor extension.