We report the case of a 49-year-old woman diagnosed with peritoneal sarcomatosis secondary to an epithelioid gastrointestinal stromal tumor (GIST) (Ki-67 3%, CD117 and DOG1 positive), initially managed with empirical carboplatin-paclitaxel, which was discontinued after histological confirmation. This evidence concerns the gene ANO1 and gastrointestinal stromal tumor.