An adnexal mass is a growth found in the adnexa, structures located near the uterus. These masses can develop at any age, with varying causes and prevalence. While many are benign, some can be malignant.
Understanding Adnexal Anatomy and Masses
The term “adnexa” broadly encompasses the anatomical structures closely associated with the uterus. These primarily include the ovaries, fallopian tubes, and the supporting ligaments. The fallopian tubes connect the ovaries to the uterus, providing a pathway for eggs. The ovaries produce eggs and hormones such as estrogen and progesterone. An adnexal mass is any growth that forms within this adnexal region. These masses vary significantly in characteristics, including size, shape, and internal composition, which can range from fluid-filled (cystic) to solid.
Common Causes and Types
Adnexal masses can arise from numerous conditions, ranging from common benign occurrences to less frequent malignant growths. The vast majority of these masses, particularly in premenopausal individuals, are benign. Functional ovarian cysts are among the most common benign types. These include follicular cysts, which form when a follicle fails to release an egg, and corpus luteum cysts, which develop after an egg is released. Both typically resolve within a few menstrual cycles.
Other benign adnexal masses include endometriomas, often called “chocolate cysts,” which are ovarian cysts filled with old menstrual blood and are associated with endometriosis. Dermoid cysts, or mature cystic teratomas, are another type, containing various tissues like hair, fat, or even teeth. Cystadenomas are benign tumors that grow on the surface of the ovary and can be filled with watery or thick, mucous-like fluid. Hydrosalpinx, a condition where a fallopian tube becomes blocked and fills with fluid, can also present as an adnexal mass.
Uterine fibroids, which are benign growths of the uterus, may sometimes be mistaken for adnexal masses if they are large or grow on a stalk. Pelvic inflammatory disease (PID) can lead to the formation of tubo-ovarian abscesses, which are infectious masses involving the fallopian tube and ovary. An ectopic pregnancy, where a fertilized egg implants outside the uterus, most commonly in a fallopian tube, is another cause of an adnexal mass that requires urgent medical attention.
While less common, adnexal masses can be malignant. Ovarian cancer is the most frequently discussed malignancy associated with adnexal masses, though fallopian tube cancer or metastatic cancer from other organs can also occur in this region. Factors such as a solid component, thick septations within the mass, or a size greater than 10 cm may raise suspicion for malignancy, especially in postmenopausal women.
Recognizing Symptoms
Many adnexal masses cause no symptoms and are found incidentally during routine exams or imaging. When symptoms occur, they vary by mass size, type, and complications. Common symptoms include pelvic pain (dull ache, sharp, or intermittent) and a feeling of pressure or bloating.
Changes in bowel or bladder habits, such as constipation or frequent urination, can result from the mass pressing on adjacent organs. Pain during sexual intercourse or abnormal vaginal bleeding, including irregular or heavier periods, may also occur.
Sudden, severe pelvic pain with nausea, vomiting, or fever can indicate an emergency like ovarian torsion or a ruptured cyst. Any new or persistent pelvic symptoms require evaluation.
Diagnosis and Evaluation
Diagnosis begins with a medical history and physical exam, including a pelvic exam. The provider asks about symptoms, menstrual history, and family history. While a physical exam can detect a mass, its low sensitivity means further investigation is often needed.
Imaging tests are crucial for characterizing an adnexal mass. Transvaginal ultrasonography is the primary imaging tool, providing details on size, shape, internal structure (cystic, solid, or mixed), and vascularity. MRI or CT scans may offer additional details or assess for spread if malignancy is suspected.
Blood tests also aid evaluation. A pregnancy test (hCG) rules out ectopic pregnancy in reproductive-aged individuals. CA-125 levels may be measured, especially in postmenopausal individuals, as elevated levels can sometimes indicate ovarian cancer. However, CA-125 can also be elevated in various benign conditions, so it is not a definitive test for cancer.
Management and Treatment Approaches
Management depends on the mass’s characteristics, symptoms, and patient factors like age and fertility. Many benign masses, especially functional ovarian cysts, resolve spontaneously. A watchful waiting approach, with periodic follow-up ultrasounds, may be adopted to monitor the mass.
Medication may be considered for some benign conditions. Hormonal contraceptives, like birth control pills, can prevent new functional cysts but do not typically resolve existing ones. For infections like tubo-ovarian abscesses, antibiotics are often the initial treatment.
Surgical intervention is necessary for large masses, persistent symptoms, malignancy suspicion, or acute complications like torsion or rupture. Laparoscopy, a minimally invasive procedure, is often preferred due to less pain, shorter hospital stays, and faster recovery than open surgery (laparotomy). Laparotomy may be needed for very large or complex cases, or confirmed/highly suspected malignancy. Treatment is individualized, considering the mass’s features, patient health, and fertility desires.