High-Grade Serous Carcinoma During Pregnancy: A Case Report and literature review

Abstract

Introduction: Pregnancy-associated ovarian cancer is a rare condition, with an estimated incidence of 1 in every 15,000 32,000 pregnancies, which leads to low clinical suspicion and delayed diagnosis. Most adnexal masses in pregnancy  are benign; however, epithelial tumors, particularly high-grade serous carcinoma, represent the most common and aggressive malignant form.

Clinical Case: We present the case of a 39-year-old woman, parity 2, at term, in whom a right ovarian mass was incidentally identified during a scheduled cesarean section, leading to salpingo- oophorectomy. Subsequent histopathological and immunohistochemical studies were consistent with high-grade serous carcinoma; however, the patient did not undergo oncological follow-up. Six months later, she presented with clinical progression, including ascites, pleural effusion, and a contralateral ovarian mass, confirming advanced stage IV disease with a marked elevation in CA-125. She is currently receiving neoadjuvant chemotherapy with paclitaxel, carboplatin, and bevacizumab.

Discussion: This case illustrates the diagnostic difficulties of ovarian cancer during pregnancy, the limited utility of tumor markers during gestation, and the importance of correctly interpreting ultrasound and intraoperative findings. It also highlights the negative impact of the lack of timely follow-up after an incidental finding, which promotes progression to advanced stages and worsens the prognosis.

Conclusion: Ovarian cancer during pregnancy remains a diagnostic and therapeutic challenge. The detection of adnexal masses during prenatal care or obstetric procedures must be accompanied by histopathological examination and close multidisciplinary follow-up. The documentation of clinical cases helps to increase diagnostic suspicion and improve early detection strategies, with the aim of reducing maternal morbidity and mortality associated with this condition.