Endocrine Abstracts

The short-term results of transsphenoidal surgery as initial treatment for acromegaly were analyzed according to consensus defining the criteria for cure of acromegaly.

Thirty nine newly diagnosed patients with acromegaly (20 females and 19 males, mean age 46.9 plus/minus 1.4 years, range 29-66 yrs), underwent transsphenoidal pituitary adenomectomy by the same neursurgeon. Patients have been assessed postoperatively at 8 weeks (GH after 75 g oral glucose was assayed by fluoroimmunoassay, and IGF-I by radioimmunoassay). Further follow-up of patients considered to be in remission consisted of IGF-I level determination only. Current consensus criteria were used to define postoperative remission: glucose-suppressed (nadir) GH less then 1.0 micrograms per litre, and a normal sex- and age-adjusted IGF-I level. The short-term remission rates (8-week postop. follow-up visit) in 39 patients as determined by nadir GH, and IGF-I level were 64%, and 56% respectively. Our study revealed a subgroup of patients (No=6) with discrepant remission criteria who, despite repetitively elevated IGF-I levels, adequately suppressed GH after glucose administration, i.e the postglucose GH nadir was less than 1 micrograms per litre. In conclusion, using stringent modern criteria for remission, transsphenoidal adenomectomy is effective and safe initial, and often definitive, treatment for the majority of patients with acromegaly, especially when done by experienced neurosurgeon. Normalization of the IGF-I level seem to be the principal criteria for documenting biochemical remission in acromegaly, because post-glucose nadir GH as measured by fluoroimmunoassay could be misleading. The discrepancies between different criteria confirm the need for their further refinement and standardization.