Ovarian cysts and breast cancer: results from the Women’s Contraceptive and Reproductive Experiences Study

Abstract

A diagnosis of ovarian cysts is likely an indicator of hormonal milieu and thus may be related to breast cancer risk. Recent studies have reported an inverse relationship between prior ovarian cyst diagnosis and breast cancer risk. We evaluated this relationship in the Women's Contraceptive and Reproductive Experiences (CARE) Study, a population-based case-control study conducted in Atlanta, Detroit, Philadelphia, Los Angeles, and Seattle. Cases had first primary invasive breast cancer diagnosed between 1994 and 1998 at ages 35-64 years. African American women were over-sampled. Controls were identified through random digit dialling and were frequency matched to cases on centre, race, and five-year age group. A total of 4575 cases and 4682 controls were interviewed. We used unconditional logistic regression adjusted for age and study centre within racial groups to estimate the odds ratio (OR) and 95% confidence interval (CI) for the relationship between prior ovarian cysts and breast cancer. Ovarian cyst diagnosis was associated with a significantly reduced risk among Caucasians (OR=0.85, 95% CI 0.76-0.96) and among African Americans (OR=0.68, 95% CI 0.57-0.81). The association in Caucasians was not significant within subgroups defined by menopausal status, hormone use, or gynecological surgery while the OR estimates in African Americans were consistently lower and frequently significant. These data are consistent with the previously reported inverse association between ovarian cysts and breast cancer, but the evidence for a relationship was stronger in African Americans than Caucasians. Additional studies are required to determine the specific cyst type(s) responsible for the observed relationship.

The Japanese Breast Cancer Society clinical practice guideline for epidemiology and prevention of breast cancer

“…A few reports have suggested an inverse association between benign ovarian cyst and breast cancer risk [51][52][53]. The mechanism is unknown, but there is an evidence of decreased breast cancer risk associated with oophorectomy for ovarian cysts [54,55].…”

Assessment of Suspicious Ovarian Masses by Comparative Study of Usg and Ct Techniques

“…On the other hand, there may be an inverse relationship between ovarian cysts and breast cancer. [8,9] Abdominal pain in the female can be one of the most difficult cases to diagnose correctly in the emergency department (ED). The spectrum of gynecological disease is broad, spanning all age ranges and representing various degrees of severity, from benign cysts that eventually resolve on their own to ruptured ectopic pregnancy that causes life-threatening hemorrhage.…”

Causes and Management of Ovarian Cysts

“…(Conversely, there could be an inverse association between breast cancer and ovarian cysts). Once ovarian cysts are large, painful, persistent or have concerning radiographic or exam findings, surgery may be required, from time to time resulting in removal of the ovary [1,2] .…”