Predictors of endoscopic transsphenoidal surgery outcome in acromegaly: patient and tumor characteristics evaluated by magnetic resonance imaging

Abstract

The availability of various first-line treatment modalities for acromegaly and evolving surgical techniques emphasize the need for accurately defined predictors of surgical outcome. We retrospectively analysed the outcome of 30 patients with acromegaly after initial endoscopic transsphenoidal surgery in two university hospitals from 2001 until 2009, and reviewed comparable literature investigating predictive tumor characteristics. Medical records were monitored for patient characteristics. Each pituitary magnetic resonance imaging (MRI) scan was revised independently by two neuroradiologists using a standardised analysis form to record distinctive predefined tumor characteristics. All characteristics were independently analysed as predictors for persistent disease, and a multivariable predictive model was created. Literature from 2000 onwards was searched for studies describing tumor characteristics predictive for surgical outcome. The cohort consisted of 27 macroadenomas with 90 % demonstrating signs of parasellar extension. The surgical cure rate overall was 30 %. Independently, next to male sex and increasing tumor size, infrasellar and parasellar extension based on MRI staging tended to increase the risk of persistent disease. In a multivariable analysis, sex and parasellar extension of the tumor were demonstrated to be the variables allowing for the best fitted predictive model for persistent disease. Earlier studies on preoperative tumor characteristics showed comparable results, although these were based on several different tumor classification systems. This retrospective study demonstrates that accurately defined tumor characteristics based on imaging, especially for cavernous sinus invasion, can be helpful in predicting surgical outcome. Comparative studies on different treatment modalities are essential for clinical practice within the scope of re-evaluation of the role of surgery in GH-secreting adenomas.

Long term follow-up of growth hormone-secreting pituitary adenomas submitted to endoscopic endonasal surgery

“…In this study, the postoperative complication rate was 56.5%, including one major complication (ischemic stroke). This result is significantly higher than observed in recent papers 1,3,4,5,11,18,23,28 , probably due to the greater prevalence of macroadenomas with extrasellar extension (65.2%) in our cohort (Figure 1). Large suprasellar and parasellar extensions with invasion of cavernous sinus may add a significant risk of complications to the procedure.…”

“…Permanent diabetes insipidus occurred in two patients (8.7%), which is a little higher than the 6.7% found by Bunderen et al 11 and our own previous experience 18 . Five patients (21.7%) developed CSF leak and two (8.7%) developed panhypopituitarism, which is in concordance with a variation of 0% to 34.8% 1,3,4,5,11,18,23,28 and 8.3% to 18.2% 5,28 , respectively, shown in recent literature. Wangenmakers et al 23 described similar epistaxis rates to our study (13% and 10%, respectively).…”

“…1 associated higher levels of suprasellar/parasellar extension and sella floor erosion with lower disease control (p = 0.01 and p = 0.02, respectively), Bunderen et al 11 . analysis reached borderline significance levels, suggesting that parasellar and infrasellar extension tend to be independent predictors of persistent disease.…”

“…Recent literature has suggested some helpful predictors for tumor gross resection and endocrine remission are tumor size 3,4,5,11,28 , extension of the lesion 1,3,4,5,11,28 and hormonal levels 4,23,28 . Concerning tumor extension, Campbell et al 3 and Buliman et al 4 evidenced that Knosp grades 3 or 4 were less likely to achieve remission.…”

“…The surgical treatment provides rapid control of GH and IGF-1 levels and it is the first line of treatment for GH-secreting adenomas 1,9,10 . In 1893, in England, the first pituitary surgery for acromegaly was performed by Caton and Paul, under the supervision of Sir Victor Horsley 11,12,13 , while the first transnasal resection of a pituitary tumor was performed by Schloffer in 1907 14 . Cushing 15 systematically used a transsphenoidal approach in sellar lesions and this technique was subsequently refined and popularized by Guiot 16 and Hardy 17,18 .…”