Tumor-Related Trigeminal Neuralgia: Clinical Features, Pathophysiology, and the Contemporary Role of Radiosurgery in Tumor Control and Pain Relief

Abstract

Trigeminal neuralgia arising from an intracranial tumor is uncommon but therapeutically distinctive because the responsible lesion is simultaneously the generator of facial pain and an independent oncological problem.When anatomically feasible, microsurgical treatment remains the preferred approach for achieving rapid, deep, and durable pain relief, particularly when decompression of the trigeminal nerve can be achieved.However, a clinically important subset of patients may be unsuitable for open surgery because of age, fitness, comorbidity, tumor anatomy, or operative risk, while others may decline surgical intervention.For these patients, radiosurgery alone represents an important noninvasive treatment strategy, although its role in pain control differs from its well-established role in tumor control.This narrative review synthesizes a purposively assembled core evidence base of 14 studies comprising comparative cohorts reporting both microsurgical and radiosurgical arms, contemporary radiosurgical series reporting pain outcomes by target, and systematic reviews and meta-analyses synthesizing either modality.The review examines tumor control and pain relief as separate therapeutic endpoints and defines what the available literature does and does not permit to be concluded.Pain outcomes are reported using each source's own threshold and are not converted between scales, and overlapping cohorts are identified and never aggregated.Across comparative cohorts and secondary pooled analyses, microsurgery was associated with a higher proportion of favorable pain outcomes and, in one meta-analysis, a longer median time to pain recurrence, with equivalent tumor control, principally in petroclival and petrous apex meningioma.Radiosurgery achieves excellent tumor control but more modest, delayed, and attenuating pain relief.Its principal role is therefore not to replace microsurgical treatment in otherwise suitable surgical candidates but to provide a noninvasive option when surgery is unsuitable, carries substantial anatomical or medical risk, or is declined.Radiosurgical pain relief cannot be explained solely by tumor volume reduction, and its mechanism remains unresolved.The characteristic radiosurgical complication is trigeminal sensory dysfunction, which is frequently permanent.Outcome definitions varied between studies, the cohorts were not independent, and none of the comparisons was randomized; therefore, observed associations cannot be interpreted as causal and may be influenced by confounding by indication.The optimal radiosurgical target remains unresolved, with every combined-target series comprising fewer than 20 patients.Anatomy-driven individualized selection, incorporating tumor-nerve relationships, surgical candidacy, nerve visibility, and the feasibility of alternative or staged treatment, remains the most defensible current approach.