From the Guidelines
Fibroids themselves are benign (non-cancerous) tumors and do not increase the chance of developing uterine cancer or other malignancies. Uterine fibroids, also called leiomyomas, are extremely common growths that develop in the muscular wall of the uterus and affect up to 70-80% of women by age 50 1. The risk of a fibroid being or becoming cancerous (leiomyosarcoma) is very rare, occurring in less than 0.1% of cases, as estimated in a study published in 2000 1. However, a more recent study from 2024 suggests that suspicion for malignancy should be increased in postmenopausal patients with fibroids and persistent abnormal uterine bleeding, fibroid growth, or both 1.
Key Points to Consider
- The natural history of fibroids is shrinkage and symptom resolution with menopause due to decreased circulating estrogen and the cessation of menses 1.
- Certain symptoms like rapid fibroid growth, especially after menopause, or sudden changes in fibroid size should prompt medical evaluation to rule out malignancy.
- It's essential to pursue endometrial biopsy prior to intervention because it can rule out endometrial neoplasia and, in some cases, diagnose sarcoma 1.
- Having fibroids does not increase your risk of developing other gynecological cancers such as endometrial or ovarian cancer.
- Regular gynecological check-ups are recommended for women with fibroids to monitor any changes, but there is no need for additional cancer screening specifically due to the presence of fibroids.
Recommendations for Clinical Practice
- Monitor women with fibroids for any changes in symptoms or fibroid size, especially after menopause.
- Perform endometrial biopsy in postmenopausal patients with fibroids and persistent abnormal uterine bleeding, fibroid growth, or both to rule out endometrial neoplasia and diagnose sarcoma if present 1.
- Educate patients on the rare risk of malignancy associated with fibroids and the importance of regular gynecological check-ups.
From the Research
Uterine Leiomyomas and Malignancy Risk
- Uterine fibroids, also known as leiomyomas or myomas, are the most common tumors of the female reproductive tract 2.
- The association between uterine fibroids and malignancy risk has been studied, with findings indicating that fibroids do not increase the risk of malignant uterine disease 2.
- Leiomyosarcomas, a type of uterine cancer, are extremely rare (less than one in 1000) and it is unknown whether they represent de novo growth or malignant transformation from benign uterine fibroids 2.
Epidemiological Studies
- A population-based study found no evidence of a higher risk of uterine malignancy in women with uterine fibroids confirmed by myomectomy 3.
- The study compared the incidence of uterine cancer in women with uterine fibroids to a control group and found no significant difference in the risk of uterine malignancy 3.
- These findings suggest that uterine fibroids do not appear to be a risk factor for uterine malignancies, and tissue injury by myomectomy does not appear to cause malignant transformation 3.
Clinical Implications
- The management of uterine fibroids should be tailored to the individual patient's symptoms, age, and desire for future fertility 4, 5, 6.
- Treatment options for uterine fibroids include medical therapy, surgical interventions, and minimally invasive techniques 2, 4, 5, 6.
- Myomectomy can be safely performed without increasing the cancer risk, and it is a viable treatment option for women with uterine fibroids 3.