The multimodal management of GH-secreting pituitary adenomas: predictive factors, strategies and outcomes

Object. The aim of this study was to analyze a series of 28 patients with acromegaly who underwent a multimodal surgical, medical and radiosurgical therapy, with a special attention to the advantages, complications, and predictive factors of a successful outcome. Methods. 28 consecutive cases of GH-secreting pituitary adenomas, who underwent transsphenoidal endoscopic or microscopic surgery, between 1 January 2014 and 31 December 2014 were retrospectively reviewed. Tumors were classified according to the diameter, measured on MRI, as micro- or macroadenomas, and parasellar (cavernous sinus) tumor extension was analyzed based on the Knosp grading score. The mean follow-up period was of 18.4 months. Criteria justifying the complete hormonal remission were preoperative basal serum GH < 2.5 μg/ L, preoperative nadirGH < 1 ng/ L after OGTT and normal preoperative IGF-I levels age and sex-matched. Results. An overall complete hormonal remission rate was achieved in 64.3% of the patients. The remission rate was higher in patients with microadenomas (77.8%) than in those with macroadenomas (57.9%). A number of predictive factors, which might have interfered with the hormonal remission rate from a statistical, clinical and paraclinical point of view, were identified: tumor size (r = 0.625), preoperative GH serum levels (r = -0.517), cavernous sinus extension was quantified according to Knosp grading score (r = 0.469) and the degree of tumor subtotal resection (r = 0.598). Conclusions. Favorable hormonal and visual remission rates can be achieved after transsphenoidal resection of GH-secreting pituitary adenomas; however, the management remains challenging, the increased surgical experience being important for higher cure rates. If a biochemical hormonal cure is not achieved postoperatively, adjuvant medical or radio surgical therapy can be recommended.