Subsequent Development of Epithelial Ovarian Cancer After Ovarian Surgery for Benign Ovarian Tumor: A Population-Based Cohort Study

Chen-Yu Huang; Wen-Hsun Chang; Hsin-Yi Huang; Chao-Yu Guo; Yiing-Jenq Chou; Nicole Huang; Wen-Ling Lee; Peng-Hui Wang

doi:10.2147/CLEP.S199349

Subsequent Development of Epithelial Ovarian Cancer After Ovarian Surgery for Benign Ovarian Tumor: A Population-Based Cohort Study

Clin Epidemiol. 2020 Jun 18:12:637-649. doi: 10.2147/CLEP.S199349. eCollection 2020.

Authors

Chen-Yu Huang^{1

2}, Wen-Hsun Chang^{3

4}, Hsin-Yi Huang⁵, Chao-Yu Guo^{4

6}, Yiing-Jenq Chou^{4

6}, Nicole Huang^{4

6}, Wen-Ling Lee^{2

7

8}, Peng-Hui Wang^{1

2

9

10}

Affiliations

¹ Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan.
² Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
³ Department of Nursing, Taipei Veterans General Hospital, Taipei, Taiwan.
⁴ Institute of Hospital and Health Care Administration, National Yang-Ming University, Taipei, Taiwan.
⁵ Biostatics Task Force, Taipei Veterans General Hospital, Taipei, Taiwan.
⁶ Institute of Public Health, National Yang-Ming University, Taipei, Taiwan.
⁷ Department of Medicine, Cheng-Hsin General Hospital, Taipei, Taiwan.
⁸ Department of Nursing, Oriental Institute of Technology, New Taipei City, Taiwan.
⁹ Female Cancer Foundation, Taipei, Taiwan.
¹⁰ Department of Medical Research, China Medical University Hospital, Taichung, Taiwan.

Abstract

Purpose: The goal of the current study is to determine the risk of subsequent development of epithelial ovarian cancer (EOC) in women after ovarian surgery for benign ovarian tumors.

Patients and methods: We conducted the nationwide population-based historic cohort study using the National Health Insurance Research Database (NHIRD) of Taiwan. Eleven thousand six hundred twenty women who underwent ovarian surgery for ovarian benign diseases were analyzed. The collected data included age, types of ovarian surgery, medical history by Charlson comorbidity index (CCI), infertility (yes/no), pelvic inflammatory disease (PID) (yes/no), tubal ligation (yes/no), total/subtotal hysterectomy (TH/STH) (yes/no), and endometrioma (yes/no). We used the Kaplan-Meier method and the Log-rank test to evaluate the risk factors. Cox proportional hazard methods were used to evaluate risk factors for the subsequent development of EOC. Multivariate analysis using Cox stepwise forward regression was conducted for the covariate selected in univariate analysis. Hazard ratio (HR) and 95% confidence interval (CI) were calculated using the Wald test.

Results: Subsequent EOC incidence rate (IR, incidence per 10,000 person-years) of women after ovarian surgery for benign ovarian tumors was 2.98. Separating into four groups based on different age, IR of EOC was 1.57 (<30 years), 4.71 (30-39 years), 3.59 (40-49 years) and 0.94 (≥50 years), respectively. Univariate and multivariate analyses identified only high level of CCI (≥2 or more) as an independent risk factor for subsequent development of EOC in women after ovarian surgery for benign ovarian tumors (HR 59.17, 95% CI 7.50-466.80 in women with CCI level of 2 and HR 190.68, 95% CI 24.33-2494.19, in women with CCI level ≥3, respectively).

Conclusion: Our results, if confirmed, suggest that women with other comorbidities (CCI) should be well informed that they may have a higher risk of subsequent development of EOC when ovarian surgery is planned even though the final pathology showed a benign ovarian tumor.

Keywords: benign ovarian tumor; cohort study; epidemiology; epithelial ovarian cancer; ovarian surgery; risk.