[Sellar collision tumors: difficulties of preoperative neuroimaging and selection of surgical approach. Case reports and literature review].

Sellar tumors are predominantly benign neoplasms accounting for approximately 14-18% of all brain tumors. For many decades, there have been a few clinical cases confirming possible simultaneous coexistence of two nosological groups in one area. We present 2 rare cases of sellar collision tumors (a 61-year-old male with pituitary adenoma and craniopharyngioma; a 68-year-old female with pituitary adenoma and meningioma of tubercle), clinical features, anamnesis, preoperative neuroimaging, intraoperative picture and postoperative outcomes. Combination of pituitary adenoma and craniopharyngioma/ meningioma as a type of collision tumors requires caution at all stages of treatment due to impossible preoperative analysis of tumor density and, accordingly, correct choice of surgical access. Transsphenoidal endoscopic access reduces mortality rate according to literature data. Preoperative MR elastometry needs to be studied in depth including patients with sellar collision tumors.