The Endoscopic Versus Open Approach for Anterior Skull Base Tumors: A Systematic Review of Comparative Outcomes and a Framework for Surgical Selection.

Background: Anterior skull base tumors (ASBTs) pose significant surgical challenges due to their proximity to critical neurovascular structures. Surgical management has evolved with the adoption of both endoscopic and open approaches. This systematic review synthesizes evidence comparing these approaches in terms of complications, outcomes, and indications. Methods: We conducted a systematic review following the PRISMA guidelines, analyzing studies published between 1981 and 2022. A total of 1200 articles were initially identified from databases including PubMed, MEDLINE, JSTOR, and ScienceDirect, with 60 relevant references ultimately included. Data extraction focused on surgical approaches, tumor types, prevalence, and complications. Results: ASBTs exhibit varying prevalence and associated complications depending on their type. Meningiomas account for nearly one-third of all cases, with an annual incidence of 2 per 100,000 individuals and recurrence rates ranging from 5% for Grade I to 50%-80% for Grade III. Common complications include anosmia (10%-20%), cerebrospinal fluid (CSF) leakage (10%), visual abnormalities, and bleeding (5%-10%). Pituitary adenomas are predominantly secretory, with microadenomas comprising 97% and macroadenomas 70%. They frequently cause damage to the internal carotid artery, optic nerve, and result in CSF leakage. Craniopharyngiomas are reported at 0.1 cases per 100,000 annually, with over 80% situated in the suprasellar region. Cavernous sinus tumors represent less than 3% of all meningiomas, while glomus tumors, more prevalent in females (6:1 ratio), present 1-3 instances per million individuals and can lead to facial paralysis, auditory impairment, and cranial nerve palsies. Chordomas and chondrosarcomas, occurring at 0.08 cases per 100,000, are more common in Caucasian men. Esthesioneuroblastomas constitute 2%-3% of intranasal neoplasms, often resulting in CSF leakage and infection. Craniofacial malignancies predominantly originate from the maxillary (60%-70%) and ethmoid sinuses (10%-15%), while skull base metastasis appears in approximately 4% of cancer patients, typically from breast, lung, renal, and prostate cancers. Surgical approaches also come with distinct complications. The endoscopic endonasal approach (EEA) has a bacterial meningitis rate of 0%-0.69%, with venous thromboembolism (VTE) being rare but more likely in older patients or those with coagulation issues. Cerebral infarction may occur due to vasospasm, subarachnoid hemorrhage, vascular damage, or electrolyte imbalances, while the risk of pneumocephalus is minimized through careful lumbar drain management and sinus precautions. Open surgical approaches commonly result in CSF leaks, meningitis, vascular injury, and visual disturbances. Conclusion: This systematic review synthesizes evidence from 60 studies to propose a decision-making framework. We conclude that the EEA is associated with superior quality of life and reduced morbidity for midline tumors (e.g., tuberculum sellae meningiomas and pituitary adenomas), offering comparable gross total resection rates. In contrast, open approaches remain paramount for tumors with significant lateral extension, massive size, or complex vascular involvement, where maximal exposure facilitates radical resection despite higher associated morbidity. This analysis provides a nuanced evidence base to guide individualized surgical strategy.