Endoscopic endonasal transsphenoidal approach to large and giant pituitary adenomas: institutional experience and predictors of extent of resection

Abstract

Pituitary adenomas are the third most common intracranial neoplasm, accounting for 10%-25% of intracranial neoplasms with a prevalence of 16.9% in autopsy studies. 6 A subgroup of these lesions that are particularly challenging to manage are those that can be classified as large or giant pituitary adenomas.2,3 Giant pituitary adenomas have classically been described as those ≥ 4 cm in maximum diameter, while large pituitary adenomas currently lack a consistent definition in existing literature. 3,7,8,11,16,17 Object. While the use of endoscopic approaches has become increasingly accepted in the resection of pituitary adenomas, limited evidence exists regarding the success of this technique for patients with large and giant pituitary adenomas. This study reviews the outcomes of a large cohort of patients with large and giant pituitary adenomas who underwent endoscopic endonasal transsphenoidal surgery at the authors' institution and focuses on identifying factors that can predict extent of resection and hence aid in developing guidelines and indications for the use of endoscopic endonasal transsphenoidal surgery versus open craniotomy approaches to large and giant pituitary adenomas.Methods. The authors reviewed 487 patients who underwent endoscopic endonasal transsphenoidal resection of sellar masses. From this group, 73 consecutive patients with large and giant pituitary adenomas (defined as maximum diameter ≥ 3 cm and tumor volume ≥ 10 cm 3 ) who underwent endoscopic endonasal transsphenoidal surgery between January 1, 2006, and June 6, 2012, were included in the study. Clinical presentation, radiological studies, laboratory investigations, tumor pathology data, clinical outcomes, extent of resection measured by volumetric analysis, and complications were analyzed.Results. The mean preoperative tumor diameter in this series was 4.1 cm and the volume was 18 cm 3 . The average resection rate was 82.9%, corresponding with a mean residual volume of 3 cm 3 . Gross-total resection was achieved in 16 patients (24%), near-total in 11 (17%), subtotal in 24 (36%), and partial in 15 (23%). Seventy-three percent of patients experienced improvement in visual acuity, while 24% were unchanged. Visual fields were improved in 61.8% and unchanged in 5.5%. Overall, 27 patients (37%) experienced a total of 32 complications. The most common complications were sinusitis (14%) and CSF leak (10%). Six patients underwent subsequent radiation therapy because of aggressive tumor histopathology. No deaths occurred in this cohort of patients. Statistically significant predictors of extent of resection included highest Knosp grade (p = 0.001), preoperative tumor volume (p = 0.025), preoperative maximum tumor diameter (p = 0.002), hemorrhagic component (p = 0.027), posterior extension (p = 0.001), and sphenoid sinus invasion (p = 0.005).Conclusions. Endoscopic endonasal transsphenoidal surgery is an effective treatment method for patients with large and giant pituitary adenomas, which results in high (> 80%) rates of resection and improvem...

Surgical outcomes of the endoscopic endonasal transsphenoidal approach for large and giant pituitary adenomas: institutional experience with special attention to approach-related complications

“…It is worth emphasizing that only one purely endoscopic surgical series was included in their analysis, since the manuscript by de Paiva Neto et al 24 was mainly microscopic transphenoidal. Thereafter, few studies came out in the literature addressing the outcomes of patients undergoing resection for large and giant pituitary adenomas by the endoscopic approach 6,8,10,11,13,14,15,16 . Their main surgical outcomes and complications rates are detailed on Tables 3 and 4 …”

“…Taking together the results of GTR, NTR and STR as an arbitrary threshold to provide satisfactory neurovascular structures decompression, the endoscopic cohort was able to achieve decompression rates of 78.9% (range 63-95%) 10,13,Present . Even though a fair comparison cannot be performed, because of a different definition for STR (residual tumor > 10-20%) 7 , the endoscopic rates of decompression are at least similar to open and microscopic transsphenoidal groups (78.8% and 81.2%, respectively) 7 .…”

“…Even though a fair comparison cannot be performed, because of a different definition for STR (residual tumor > 10-20%) 7 , the endoscopic rates of decompression are at least similar to open and microscopic transsphenoidal groups (78.8% and 81.2%, respectively) 7 . Finally, the surgical technique used by most of the endoscopic endonasal series is the standard approach, in which a wide exposure of the sellar floor is obtained from the medial walls of the cavernous sinus laterally, the tuberculum sellae cranially and the dural indentation of the clivus/inferior transcavernous sinus caudally 6,8,10,11,14,16 . Some studies have used the extended transplanum/transtuberculum endonasal approach to address some dumbbell-shaped or suprasellar adenomas or even fibrous tumors 6,8,10,13,14,15 .…”

“…Some recent reports have described the usefulness of the endoscopic endonasal route in the their management, even though its safety and effectiveness of treating large and giant pituitary adenomas is yet to be established in the literature 6,8,10,11,13,14,15,16 . Herein, we sought to investigate our institutional experience of patients who underwent endoscopic endonasal transsphenoidal approach for treatment of large and giant pituitary adenomas emphasizing the surgical results and approachrelated complications.…”

“…There is no consensus, however, on the definition of large pituitary adenomas 8,9 . Juraschka et al 10 have considered large tumors as those having > 3 cm in the maximal diameter, while Cusimano et al 11 have introduced a new volumetric assessment (≥ 10 cm 3 ) on the assumption of a better estimation of the tumor size and also for a better quantification of the extent of resection.…”