Exploring endocrinological pitfalls in pituitary surgery in the elderly

BACKGROUND: Endoscopic transsphenoidal surgery (ETSS) is performed more frequently in elderly patients. We investigated endocrinological pitfalls in pituitary surgery in the elderly by a comparative study focusing only on elderly patients. METHODS: Ninety-nine elderly patients aged 65 years and over with non-functioning pituitary adenoma (NFPA) who underwent ETSS were retrospectively examined and classified into the early (aged 65–74 years) and late (aged 75 years and over) elderly groups. The baseline characteristics and anterior pituitary function were compared between the groups. RESULTS: Seventy patients were assigned to the early elderly group and 29 to the late elderly group. Thyroid-stimulating hormone (TSH) response in preoperative and postoperative thyrotropin-releasing hormone (TRH) tests revealed a significant difference between the groups. Preoperative and postoperative TSH responses were significantly correlated in both groups. Residual analysis of the correlation between preoperative free triiodothyronine (T3) secretion quantity and preoperative TSH response in both groups, which was significant, indicated that preoperative TSH response was significantly normal when preoperative free T3 secretion quantity was normal in the early elderly group, but preoperative free T3 secretion quantity was significantly lower regardless of preoperative TSH response in the late elderly group. CONCULSIONS: The present study suggested that preoperative and postoperative TSH secretory capacity was presumed to be normal when preoperative free T3 levels were normal in the early elderly patients with NFPA. On the other hand, TSH secretory capacity in the late elderly patients could only be assessed by the TRH test, which should be taken into account.