First-trimester miscarriage in the background of endometrial carcinoma

•Endometrial cancer during miscarriage of non-viable pregnancy is rare. They may present as a miscarriage and diagnosis can be confirmed through histopathological examination. This emphasis the importance of histology evaluation of product of conception (POC) in high-risk patients.•In case of endometrial cancer in young patient with fertility concern, the patient and partner should be counselled with emphasis of compliance to treatment and regular surveillance which include hysteroscopy every 3–6 monthly.•Young patient with endometrial cancer usually has good prognosis and favorable pregnancy rate following disease regression. Endometrial cancer in young women (less than 40-year-old) is associated with anovulatory menses, polycystic ovarian syndrome (PCOS) and subfertility. Endometrial cancer occurring in a miscarriage is rare. We highlight a case of endometrial cancer occurring during miscarriage of a non-viable pregnancy, its management and the outcome. A 32-year-old woman, Gravida 1 Para 0, was referred to our center at 7 weeks gestation in 2018 for uncontrolled diabetes mellitus diagnosed during investigation for subfertility. Her poor compliance with the treatment is consistent with an HbA1c of 8%. During the assessment, she was already complaining of lower abdominal pain. Ultrasound showed irregular IUGS with no fetal echo. She had a miscarriage soon; however, due to ultrasound evidence of thickened and irregular endometrium (17 mm) with mixed echogenicity, dilatation and curettage (D + C) were commenced. The first and second tissues were reported as the product of conception (POC) and well differentiated endometrioid adenocarcinoma, respectively. The first hysteroscopy showed foci area of polypoidal growth at the right posterior endometrium, obscuring the right ostium, with similar histology report. She was commenced on high-dose progestogen with hysteroscopy surveillance 6 months later, which showed disease regression. After two normal hysteroscopies and endometrial biopsies with continuous progestogen therapy for 12 months, cyclical progestogen for 12 months and follow-up for another 6 months, she had spontaneous conception and is currently pregnant at 16 weeks gestation. Endometrial cancer should be suspected in high-risk patients with first-trimester miscarriage. Individualized treatment with high dose progestogen and follow-up with the proper patient and partner counselling and education has high successful regressionand later on, pregnancy rat