Primary gastric extra-uterine endometrial stromal sarcoma

Endometrial stromal sarcoma (ESS) is an uncommon uterine neoplasm, but its occurrence as an extra-uterine primary (EESS) is exceedingly unusual, and the fine-needle aspiration (FNA) cytopathology of EESS is rarely described. We hereby present 2 women with primary gastric EESS whereby the FNA cytopathology of this rare entity showed a population of cytologically monotonous oval-spindle shaped cells. This cytopathology is correlated with the subsequent histopathology. EESS is another, albeit rare, diagnostic consideration along with gastrointestinal stromal tumor, schwannoma, glomus tumor, and leiomyoma of cytologically bland neoplasms of the stomach that can be encountered using endoscopic ultrasound-guided FNA biopsy.