Abstract
BACKGROUND: The locations of pituitary neuroendocrine tumor (PitNET) and anterior clinoid meningioma (ACM) appear to be very close but essentially different, as the former is inside the sella turcica while the latter is in the intradural space. A collision tumor thus requires a specific treatment strategy but has been rarely reported. OBSERVATIONS: A 77-year-old woman presented with progressive visual impairment due to significant compression of the optic apparatus by a collision of PitNET and ACM. With a minimally invasive two-stage therapeutic strategy, the ACM was first resected using an endoscopic mini-pterional approach, then the PitNET was removed with an endoscopic transnasal approach 8 weeks later, leading to significant improvement in visual function. The authors' literature search identified only 2 documented cases of a similar collision. LESSONS: This case underscores the complexity of the decision-making process in the management of collision tumors and suggests the potential benefit of staged minimally invasive surgical interventions in preserving visual function. Further accumulation of cases is warranted for refining the treatment strategy. https://thejns.org/doi/10.3171/CASE24240.