PT - JOURNAL ARTICLE AU - E Pertossi AU - N Saez AU - M Urzúa AU - P LeCerf AU - O Puga TI - 89 Large cell neuroendocrine carcinoma (LCNEC) of the endometrium : case report at hospital Sótero Del Río, Chile AID - 10.1136/ijgc-2020-IGCS.84 DP - 2020 Nov 01 TA - International Journal of Gynecologic Cancer PG - A46--A46 VI - 30 IP - Suppl 3 4099 - http://ijgc.bmj.com/content/30/Suppl_3/A46.short 4100 - http://ijgc.bmj.com/content/30/Suppl_3/A46.full SO - Int J Gynecol Cancer2020 Nov 01; 30 AB - Introduction Type I endometrial carcinoma (EC) is the most common uterine cancer, with known risk factors as obesity. Type II EC is less frequent, with high risk histologies including LCNEC.Case A 62-year-old woman with type 2 diabetes, hypertension and obesity who had menopausal bleeding with an enlarged uterus, up to the umbilicus. CT-scan showed an enlarged uterus with a solid tumor filling the cavity and no evidence of dissemination. Endometrial sampling was performed with no evident dysplasia. Laparotomy revealed a 24 cm uterus and enlarged pelvic lymph nodes. TH+BSO was performed. Frozen section informed high grade carcinoma. Pelvic and para-aortic lymphadenectomy and omentectomy were then performed. Definitive pathology concluded a LCNEC of the endometrium infiltrating 93% of the myometrium with LVI+, without extrauterine spread (Stage IB). Afterwards, the patient received 6 cycles of etoposide plus cisplatin. To date, she’s been 20 months disease free.Discussion LCNEC of the endometrium has 28% 5-year overall survival. A recently published case series concludes that menopausal bleeding is the most common symptom. This aggressive histology has been included into type II EC, nevertheless, there is no consensus on pathologic criteria for diagnosis. WHO refers that diagnosis should be done with the presence of large carcinoma cells and high mitosis count, and presence of any of the following IHQ stains: chromogranine A, synaptophysin, CD56 or enolase enzyme. Here, the diagnosis was based on typical architectural large cells and CD56 positivity.