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...

H istorically, non-Indigenous researchers carried out the majority of research in Indigenous (First Nations, Inuit and Métis Peoples) communities in Canada. 1 In this context, research rarely had direct benefits for the communities being studied and sometimes resulted in harms. 1-6 As a result, there is commonly a sense of apprehension and mistrust among Indigenous communities toward research by non-Indigenous researchers. 1 There are several Canadian policy documents with similar themes that guide research in Indigenous communities.