Incidental finding of endometrial carcinoma in a first-trimester miscarriage mimicking molar pregnancy: a case report and review of literature

Abstract

Background: Endometrium cancer is the most common gynecological cancer in women from developed countries. However, endometrial cancer is rarely seen during pregnancy. In literature, there are 34 cases reported since 1996 and majority were detected in the first trimester. We present a case of endometrial carcinoma in the background of suspected molar pregnancy. Case presentation: A 39-year-old gravida 3 para 1 lady presented at 5 weeks and 3 days amenorrhea with per vaginal bleeding in Dec 2022. Her serum beta-HCG was 14,634 IU/L and the ultrasound pelvis showed echogenic material in the endometrial cavity with no gestational sac. A follow-up serum beta-HCG at 48 h showed a suboptimal rise to 22,546 IU/L. Findings on a repeat ultrasound pelvis were suspicious of a molar pregnancy. She underwent evacuation of uterus. The histology showed focal well differentiated endometrioid adenocarcinoma with background hyperplasia with and without atypia. Products of conception were also confirmed. Staging scans confirmed radiological stage 1 disease. She declined fertility sparing treatment and opted for definitive surgery. She underwent a total laparoscopic hysterectomy, bilateral salpingectomy with sentinel lymph node biopsy. The final histology showed complex atypical hyperplasia with no residual endometrial adenocarcinoma. The patient recovered well and remained disease-free 21 months after surgery. Conclusion: Suspicious radiological findings in early pregnancy should prompt meticulous histological evaluation to rule out malignancy. Although endometrial cancer is very rare in pregnancy, it is important for clinicians and pathologists to have high index of suspicion of this possible differential diagnosis.