Surgical treatment of endometriosis can reduce the risk of epithelial ovarian cancer, suggests a new study.
Swedish researchers identified 220 cases of women with endometriosis and epithelial ovarian cancer at least one year after the diagnosis of endometriosis and 416 women with endometriosis as controls. They recorded all hormonal treatments and surgery such as hysterectomy (83 women of the case group, 157 of controls), unilateral oophorectomy (45 of cases, 152 of controls), sterilization by tubal ligation or bilateral salpingectomy (24 and 68 respectively) and complete removal of endometriosis (52 cases and 201 controls). The median age at diagnosis was 38.2 years for the cases and 40.1 years for controls; 66.85 of cases and 54.15 of the controls had ovarian endometriosis.
Surgical removal of the affected ovary had the highest risk reduction (81%) of developing epithelial ovarian cancer followed by complete surgical removal of all visible endometriotic tissue (30%), compared with other surgical treatments. The risk reduction increased when women with adenomyosis were excluded. None of the other surgical treatments were shown to significantly lower the risk of developing ovarian cancer, compared with surgical removal. No association was found between combined oral contraceptives and ovarian cancer.
What this study means to GPs
Study leader Dr Anna-Sofia Melin, a consultant at the Karolinska Institute in Stockholm, Sweden, said: ‘Our study suggests that surgical removal of an ovary and removal of visible endometriosis protects women from developing ovarian cancer at a later point. For women with endometriosis, the role of hormonal treatment and future ovarian cancer risk remains unclear and further investigation is warranted.’