Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 61 3 2023 05 14 181 186 Helena Azimi Department of Obstetrics and Gynecology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Seyyed Rasoul Sajjadi Department of Critical Care Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Shohreh Saeed Department of Obstetrics and Gynecology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Maryam Nakhaee Department of Obstetrics and Gynecology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Amir Hosein Jafarian Department of Pathology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Behroouz Davachi Department of Radiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Arezoo Naderi Moghaddam Department of Obstetrics and Gynecology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Toktam Dehghani Department of Medical Informatics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Zohreh Yousefi Department of Obstetrics and Gynecology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran 2021 01 19 2023 01 21 Ovarian cancer management during pregnancy is a topic of limited research due to low occurrence rates of malignant adnexal tumors. To shed further light on this issue, we present a case series of 22 pregnant ovarian cancer patients referred to an academic hospital's gynecology oncology department over six years. Data on each patient's demographic and clinical background were collected using a registry software recording surgical tumor staging, disease-free survival (DFS), and overall survival (OS). According to the data analysis reports, subtype epithelial tumor and germ cell pathology were equally 45.4%. However, sex-cord tumors were observed in a smaller percentage of cases (9.1%). Serous adenocarcinoma was the most common subtype among those with epithelial tumors (60%). Meanwhile, 72.7% of these pregnant women had a palpable mass in physical examination. In addition, adnexal mass was detected in 95.4% of ultrasonography. Due to the young age of the patients, fertility-preserving surgery was performed on 63.6% of patients, and chemotherapy was prescripted on 59% of patients. Over a six-year follow-up period, there was a recurrence rate of 22.7%, while DFS and OS were reported as 56% and 82%, respectively. In conclusion, treatment of ovarian malignancies during pregnancy requires an experienced multidisciplinary approach. However, more extensive studies with larger samples are needed to gain more insight into the treatment of ovarian cancer during pregnancy.   https://acta.tums.ac.ir/index.php/acta/article/view/9104 https://acta.tums.ac.ir/index.php/acta/article/download/9104/5768