Large Endometrioma of the Ovary - a case study

Background: Endometriosis is a chronic condition characterized by pelvic pain, dysmenorrhea, and infertility that affects 6-10% of women of reproductive age. It is thought to be caused by retrograde menstruation leading to implantation of endometrial stroma to the peritoneum. Clinical presentations of endometriosis are varied, with symptoms such as dysmenorrhea and adnexal masses being common. Adnexal masses can be evaluated with transvaginal ultrasounds and MRI, but the only conclusive diagnosis is surgery and biopsy. Endometriomas are ovarian cysts that form endometriotic lesions. They can be painful and lead to infertility, and also have a small chance of malignancy. Tumor marker levels of CA-125 can be increased in both benign and malignant endometriomas, and malignancy can only be ruled out with biopsy. The primary treatment for endometriomas is removal, as drainage is associated with a high rate of recurrence. Case information: A 38-year old female was referred to the clinic for evaluation of an adnexal mass. She complained of pelvic pain, dysmenorrhea and abnormal uterine bleeding on initial presentation. Abdominal MRI revealed a multilocular right adnexal mass measuring 13.5 x 10.4 x 11.2 cm with a small amount of surrounding fluid. Tumor markers drawn were found to be elevated. The patient had a follow up 8 months later and transvaginal ultrasound revealed the mass had enlarged to 19.36 x 13.30 x 13.06 cm. Total laparoscopic hysterectomy with bilateral salpingo-oophorectomy was performed and a 20 cm right adnexal mass consistent with ovarian endometrioma containing 1240 mL of endometriotic fluid was evacuated. Conclusions: Endometriomas are one of the most common ovarian masses in women of reproductive age, present in 17-44% of women with endometriosis. They are rarely above 10-15 cm in diameter, and current studies show that only endometriomas over 4 cm in diameter should be surgically removed. Despite being so common, diagnosis is difficult to get certain because most adnexal masses cannot be definitively diagnosed without a biopsy. Other possible causes of adnexal masses include ovarian cysts, ectopic pregnancy, fibroids, ovarian cancer, and pelvic inflammatory disease. There is currently no effective screening tool for ovarian masses. Often screening is done by transvaginal ultrasound and serum levels of CA-125, an ovarian tumor epithelial growth marker. Endometriomas can cause high levels of CA-125, leading to false positives of ovarian cancer. Other conditions that can cause high levels of CA-125 in the absence of malignancy are menstruation, pregnancy, pelvic inflammatory disease, and benign pelvic tumors. Removal of endometriomas can be complicated for women that want to reproduce because it can damage ovarian tissue. Because the definitive diagnosis of endometriomas and adnexal masses is difficult, a need exists to develop a type of screening tool for ovarian masses before they progress to a point where surgery is required. CA-125 levels are not a reliable measure of malignancy as many non-malignant conditions can create false positives. Potential benefits of early screening include identification of ovarian tumors and prevention of unnecessary surgery, especially in reproductive age women.