A pituitary mass in a 46‐year‐old woman.

This article discusses the case of a 46-year-old woman who presented with left retro-orbital headaches and other symptoms. Magnetic resonance imaging (MRI) revealed a 2.7 cm pituitary mass. Intraoperative and histological examinations showed a poorly differentiated neoplasm with high mitotic counts and loss of nuclear SMARCB1/INI1 staining. Chromosomal microarray analysis and next-generation sequencing detected copy neutral loss of heterozygosity (cnLOH) in chromosome 22 and a frameshift deletion in the SMARCB1 gene. The tumor was classified as an adult sellar atypical teratoid/rhabdoid tumor (AT/RT) and was found to be of the MYC subtype. The article emphasizes the rarity of adult sellar AT/RT and the importance of accurate diagnosis through molecular and cytogenetic analysis. [Extracted from the article]