Endometrial polyps are common growths that develop in the inner lining of the uterus, known as the endometrium. These growths are typically soft, stalk-like structures that project into the uterine cavity. They can vary in size, from a few millimeters to several centimeters. While frequently encountered, their presence often raises questions about their nature and potential implications.
Understanding Endometrial Polyps
Endometrial polyps are benign, non-cancerous growths. They originate from an overgrowth of the endometrial tissue lining the uterus. They are composed of glandular tissue, fibrous stroma, and blood vessels, resembling the normal uterine lining but in a localized, excessive manner. The formation of these polyps is often linked to an overstimulation of the endometrium by estrogen.
They can appear as single growths or multiple polyps within the uterine cavity. While most polyps remain small, some can grow larger and potentially fill a significant portion of the uterus. Many individuals will develop them, often without noticeable symptoms.
Factors Influencing Cancer Risk
While the majority of endometrial polyps are benign, a small percentage can harbor pre-cancerous cells or, less commonly, cancerous cells. The risk of a polyp being malignant is low, estimated between 0.5% and 5%. This risk increases with certain factors. It is important to distinguish between a polyp being cancerous and a benign polyp transforming into cancer over time; the former is more frequently observed.
Age is a significant risk factor, with postmenopausal women having a higher likelihood of malignant or pre-cancerous polyps, with the risk being around 5-6% compared to 1-2% in premenopausal women. Larger polyps, particularly those exceeding 10 milliliters in volume or length, are also associated with an increased risk of malignancy. Multiple polyps may also correlate with a higher risk.
Certain symptoms, such as post-menopausal bleeding, increase the suspicion of malignancy within a polyp. The use of Tamoxifen, a medication often prescribed for breast cancer, is known to increase the risk of developing endometrial polyps and can elevate the risk of these polyps being malignant. Other health conditions, including obesity, polycystic ovary syndrome (PCOS), and elevated fasting glucose levels, are associated with increased estrogen exposure, which can stimulate endometrial growth and potentially contribute to the development of malignant polyps.
Recognizing Potential Symptoms
Many endometrial polyps are asymptomatic and often discovered incidentally during imaging for other conditions. However, when symptoms do occur, they are primarily related to abnormal uterine bleeding. This can manifest as heavy menstrual periods, known as menorrhagia, or irregular periods where the timing and flow vary unpredictably. Bleeding between menstrual cycles, or intermenstrual bleeding, is another common presentation.
Post-menopausal bleeding is a particular concern and warrants immediate medical evaluation, as it is the most significant symptom associated with a higher risk of malignancy in endometrial polyps. Other less common symptoms include heavy vaginal discharge, which can be a persistent or intermittent issue. In some instances, polyps can interfere with fertility by obstructing the fallopian tubes or impeding embryo implantation, leading to difficulty conceiving.
Diagnosis and Management
Diagnosis of endometrial polyps begins with imaging techniques. A transvaginal ultrasound is often the initial screening method, providing images of the uterus and its lining. However, its ability to definitively identify polyps can be limited. Sonohysterography, also known as saline-infusion sonography, enhances the clarity of the uterine cavity by distending it with sterile saline during an ultrasound, offering a clearer visualization of any growths.
The gold standard for both diagnosis and removal of endometrial polyps is hysteroscopy. This procedure involves inserting a thin, lighted telescope-like instrument through the vagina and cervix into the uterus, allowing for direct visualization of the uterine cavity. During hysteroscopy, the physician identifies the polyp’s location and size, and often perform a hysteroscopic polypectomy (surgical removal). An endometrial biopsy may also be performed during hysteroscopy, taking a tissue sample for microscopic examination.
Once removed, the polyp is sent for pathological examination to determine its exact nature—whether it is benign, pre-cancerous (atypical hyperplasia), or cancerous. This microscopic analysis is important for confirming the diagnosis and guiding further management. For small, asymptomatic polyps, particularly in pre-menopausal women, a period of observation might be considered. However, symptomatic polyps or those with concerning features are recommended for removal. Follow-up recommendations will depend on the pathology results and individual risk factors.