An ovarian cyst is a fluid-filled sac that forms on or within an ovary. These sacs are common, typically do not cause symptoms, and are harmless. They frequently resolve on their own without needing specific medical treatment.
Measuring Ovarian Cysts and Typical Sizes
Medical professionals measure ovarian cysts using imaging techniques, primarily ultrasound. It uses sound waves to create images of the pelvic organs, with measurements given in centimeters. During a typical menstrual cycle, a follicle grows on the ovary, releasing an egg during ovulation. If the follicle does not release an egg or the sac does not dissolve, it can form a functional cyst. Functional cysts are the most common type and are considered a normal part of ovarian function. These cysts are benign and typically measure less than 5 to 6 centimeters. Many resolve spontaneously within a few weeks or months, often within one to two menstrual cycles.
When an Ovarian Cyst is Considered Large
While there is no single universal “too big” number, size is a significant indicator for increased medical attention. Cysts larger than 5 centimeters may warrant closer monitoring. Those reaching 5 to 10 centimeters are often medium-sized and require more frequent observation. Cysts measuring 10 centimeters (about 4 inches) or greater are often considered large and may lead to intervention.
These larger cysts have an increased chance of complications like ovarian torsion, the painful twisting of the ovary, potentially cutting off its blood supply, or rupture, which can cause severe pain and internal bleeding. While most ovarian cysts are non-cancerous, larger cysts with certain characteristics may prompt further evaluation for cancer.
Beyond Size: Other Factors in Assessment
Beyond size, doctors evaluate several other factors when assessing an ovarian cyst. These elements provide a comprehensive understanding of the cyst’s nature and potential implications.
Symptoms
Symptoms play a role, including pelvic pain, bloating, frequent urination, discomfort during bowel movements, pain during sexual intercourse, or irregular menstrual periods.
Imaging Appearance
The cyst’s appearance on imaging (typically ultrasound) offers important clues. Features like solid components, internal divisions (septations), or specific blood flow patterns within the cyst indicate whether it is simple and fluid-filled or more complex. Simple cysts, which are fluid-filled with thin walls, are usually benign, while complex cysts, which may contain thicker fluid, blood, or solid areas, may require closer examination.
Patient Factors
A patient’s age and menopausal status are important considerations. Cysts found in post-menopausal individuals are viewed with increased caution, as the risk of cancer is slightly higher after menopause. Different types of cysts exist, including functional cysts, dermoid cysts, endometriomas, or cystadenomas. The rate at which a cyst grows can influence medical decisions, as rapid growth may raise additional concerns.
Blood Tests
Blood tests, such as the CA-125 tumor marker, may be used if there is a higher suspicion for malignancy. However, elevated CA-125 levels can occur in non-cancerous conditions.
Next Steps and Treatment Options
Once an ovarian cyst has been assessed, several approaches may be considered.
Watchful Waiting
For smaller, asymptomatic cysts that appear benign, watchful waiting is common. This involves monitoring the cyst over time with follow-up ultrasound scans to see if it resolves on its own or changes in size or appearance.
Medical Management
Medical management, though less common for addressing cyst size directly, may include hormonal contraceptives. These medications can help prevent new functional cysts by stopping ovulation, but they do not typically shrink existing ones. This can be a suitable option for individuals who frequently develop functional cysts.
Surgical Intervention
Surgical intervention is considered when a cyst is large, causes persistent symptoms, or exhibits concerning features like suspicious imaging characteristics or rapid growth. Surgery may be recommended if there is a suspicion of malignancy. The type of surgery depends on the cyst’s size and characteristics. Laparoscopic surgery, a minimally invasive procedure involving small incisions, is often preferred for smaller cysts. For large cysts or when cancer is a concern, an open surgical procedure, known as a laparotomy, which involves a larger incision, may be necessary. Treatment decisions are individualized and made in consultation with a healthcare provider.