Risk of secondary malignancies in patients with ovarian cancer: a systematic review and meta-analysis

Objective: This study was performed to systematically assess the risk of secondary malignancies in patients with ovarian cancer. Methods: A systematic search was conducted in PubMed, Web of Science, and Scopus databases up to September 2019. In this study, the overall standardized incidence ratio (SIR) was calculated applying fixed/random-effects models. Sixteen cohort studies, including 122715 ovarian cancer patients with 4458 secondary malignancies were included. Results: Combined SIRs showed an increased risk of secondary malignancies prevalence (SIR = 1.81, 95% CI 1.58-2.03). The most common malignancies were cervical cancer 11.57 (6.94-16.21), endometrium 6.31 (4.18-8.44), leukemia 3.33 (2.23-4.43), connective tissue 2.61 (1.56-3.66), bladder 2.13 (1.77-2.50), renal 1.43 (1.11-1.74), intestine 2.36 (1.11-3.61), colorectal 1.73 (1.44-2.02), pancreatic 1.42 (1.13-1.71), breast 1.34 (1.5-1.18), and thyroid 1.59 (1.13-2.04) cancers. Conclusion: Some malignancies were found to be highly prevalent in patients with ovarian cancer compared to the general population, including endometrial cancer, leukemia, connective tissue malignancy, and bladder cancer. Therefore, efforts for early detection, which could lead to improved survival should be taken in these patients.