Microscopic Transsphenoidal Resection of Giant Pituitary Adenomas: Analysis of the Factors Limiting the Degree of Resection in 73 Cases

Abstract

PurposeTo analyze the risk factors affecting the gross-total resection of giant pituitary adenomas using a transsphenoidal approach under a microscope to provide a reference basis for formulating an appropriate surgical strategy.MethodsThe clinical data of patients who underwent microscopic transsphenoidal resection of giant pituitary adenomas in a single center from January 2011 to December 2020 were retrospectively analyzed. Based on magnetic resonance imaging and surgical records, the predictive factors affecting the gross-total resection of giant pituitary adenomas under microscopy were determined through univariate and multivariate analyses.ResultsA total of 73 patients with giant pituitary adenomas underwent transsphenoidal microsurgery. Gross-total resection was performed in 19 cases (26%), subtotal resection in 31 cases (42%), partial resection in 21 cases (29%), and the degree of resection was <50% in only two cases (3%). After binary logistic analysis, it was found that it was more difficult to completely remove giant pituitary adenomas with a Knosp grade 3–4 [odds ratio (OR) = 0.214, 95% confidence interval (CI): 0.05–0.917; P = 0.038], greater proportion of tumor suprasellar volume (odds ratio = 0.937, 95% confidence interval: 0.898–0.978; P = 0.003), and intraoperative evidence of invasion of the cavernous sinus (odds ratio = 0.187, 95% CI: 0.039–0.898; P = 0.036).ConclusionIt is difficult to remove a giant pituitary adenoma invading the cavernous sinus completely with a higher degree of invasion of the suprasellar region using microscopic transsphenoidal surgery. The combined application of multiple surgical methods can help to improve the degree of resection during a single operation.

Comparison of Clinical Outcomes between Microscopic and Endoscopic Transsphenoidal Pituitary Tumor Resection

“…24 Special care to remove the tumor and relieve the mass effect without compromising neurological function to the greatest degree is important to ensure the survival and quality of life of patients with pituitary tumors, and this has remained a challenge. 25,26 Our analysis studying the duration of surgery showed that gross total resection was a predictor of a shorter surgery, regardless of surgical approach. This finding could be due to the soft consistency of an adenoma, making gross total resection achievable.…”

“…28 Other barriers to a gross total resection of pituitary tumors can be the anatomical location of the tumor, specifically if it has a greater suprasellar extension or cavernous sinus invasion. 25,26 A study by Pei et al studied factors limiting gross total resection in pituitary adenomas and found that with microscopic resection, cavernous sinus invasion and greater suprasellar expansion can serve as obstacles towards achieving gross total resection. 25 However, our analysis did not indicate a significant interaction between cavernous sinus invasion, suprasellar extension, and gross total resection.…”

Letter: A Multicenter, Propensity Score–Matched Assessment of Endoscopic Versus Microscopic Approaches in the Management of Pituitary Adenomas

“…This assumption is incorrect because a minority of PitNETs might require transcranial surgery 6 ; furthermore, it is known that ETSS might allow the resection of PitNETs that would not be treated safely with MTSS. 6-8…”

“…This assumption is incorrect because a minority of PitNETs might require transcranial surgery 6 ; furthermore, it is known that ETSS might allow the resection of PitNETs that would not be treated safely with MTSS. [6][7][8] Tumor dimensions were graded only as microadenomas or macroadenomas, making it impossible to extrapolate the prevalence of giant adenomas in the studied cohort. Centers using only microsurgery might have treated larger PitNETs with transcranial rather than TS.…”