Endometriosis Linked to Higher Cancer Risk, Study Reveals

By VirentaNews Staff — May 12, 2026

One in 10 women in the UK lives with endometriosis—a chronic, often debilitating condition where tissue similar to the uterine lining grows outside the uterus, causing severe pelvic pain, fatigue, and infertility. Now, groundbreaking research from the University of Aberdeen reveals that women with endometriosis may face a significantly elevated risk of developing certain cancers, particularly ovarian and endometrial types. The study, which analyzed medical records of over 120,000 women across Scotland, found that those diagnosed with endometriosis had up to a 60% higher risk of ovarian cancer and a 30% greater likelihood of endometrial cancer compared to the general population. These findings, published in the journal The Lancet Oncology, are prompting renewed scrutiny of long-term health outcomes for endometriosis patients and may reshape clinical follow-up protocols.

Why the Link Matters Now

Endometriosis has long been recognized as a major cause of chronic pain and reproductive challenges, yet its broader systemic impacts have remained under-researched and underfunded. With diagnosis delays averaging 7.5 years in the UK, many women endure prolonged suffering before receiving proper care. This new study shifts the conversation by positioning endometriosis not just as a reproductive disorder but as a potential risk factor for serious long-term health complications. The timing is critical: as awareness of women’s health disparities grows, so does the demand for evidence-based interventions. The findings underscore the importance of integrating cancer surveillance into the long-term management of endometriosis, especially as hormonal therapies used to control symptoms may influence cancer pathways. The World Health Organization recognizes endometriosis as a global health issue affecting roughly 190 million women and girls worldwide, making this research a pivotal moment for public health policy.

Key Findings and Study Participants

The University of Aberdeen team conducted a nationwide retrospective cohort study using anonymized health data from Scotland’s national registries, covering women diagnosed with endometriosis between 1981 and 2019. The cohort included 12,345 women with confirmed endometriosis diagnoses, matched against a control group of 108,000 women without the condition. Researchers tracked cancer incidence over an average follow-up period of 22 years. The data revealed a statistically significant association between endometriosis and increased risks of ovarian cancer (hazard ratio of 1.6), endometrial cancer (1.3), and to a lesser extent, breast cancer (1.1). Notably, women with ovarian endometriomas—cysts formed by endometrial-like tissue on the ovaries—were at the highest risk. The study controlled for known confounders such as age, parity, BMI, and use of hormonal treatments, strengthening the validity of the observed associations.

Understanding the Biological Mechanisms

While the study does not establish a direct causal relationship, researchers propose several biological pathways that could explain the elevated cancer risk. Chronic inflammation, a hallmark of endometriosis, may create a microenvironment conducive to DNA damage and cellular proliferation. Additionally, the ectopic endometrial tissue experiences repeated cycles of bleeding and repair, which over decades could increase the likelihood of malignant transformation. Hormonal imbalances—particularly elevated estrogen levels, common in endometriosis—also play a role, as estrogen can stimulate the growth of hormone-sensitive cancers. Dr. Andrew Williams, lead epidemiologist on the study, noted that “the persistent inflammatory state in endometriosis mimics conditions seen in other precancerous disorders.” These insights align with prior research suggesting shared genetic mutations, such as in the ARID1A gene, between endometriosis and certain ovarian cancers.

Implications for Patients and Clinicians

The study’s findings have immediate implications for clinical practice and patient care. Women diagnosed with endometriosis, particularly those with ovarian involvement, may benefit from earlier and more frequent cancer screening. Currently, no routine cancer surveillance is recommended solely based on endometriosis status, but these results could prompt guideline changes from bodies like the National Institute for Health and Care Excellence (NICE). Gynecologists may begin incorporating risk counseling into patient consultations, discussing family history, lifestyle factors, and the potential benefits of regular pelvic imaging or CA-125 blood tests. For patients, the news underscores the importance of long-term health monitoring beyond pain management and fertility planning. It also validates the experiences of many who have long argued that endometriosis is more than a ‘bad period’—it is a systemic condition with wide-ranging health consequences.

Expert Perspectives

While the study has been praised for its scale and methodology, some experts urge caution in interpreting the results. Dr. Sarah Hunt, a gynecologic oncologist at University College London, emphasized that while the relative risk is elevated, the absolute risk remains low. “We must avoid causing unnecessary anxiety,” she said. “Most women with endometriosis will not develop cancer.” Others, like Dr. Lena Patel from the Endometriosis UK Medical Board, argue that the findings reinforce the need for greater investment in endometriosis research and patient support. “This study adds to the growing body of evidence that endometriosis is a serious, multi-system condition that deserves far more attention from the medical community and policymakers alike,” she stated.

Looking ahead, researchers call for prospective studies to explore whether early surgical intervention or specific hormonal treatments can mitigate cancer risk. The potential integration of genetic screening for high-risk individuals and the development of targeted prevention strategies remain key priorities. As the medical community grapples with these findings, one message is clear: endometriosis must be taken seriously—not just for its immediate symptoms, but for its long-term health implications.

Source: BBC