Watchful waiting of ovarian cysts
Is watchful waiting of an ovarian cyst a good idea?
The answer is: it depends on the type of ovarian cyst, and also whether you are pre or post-menopausal.
If you have a simple functional ovarian cyst and are pre-menopausal, then watchful waiting is the best option.
If the cyst is complex or if you are post-menopausal then the answer is more complicated. It is initially important to assess other factors such as symptoms (e.g. pain, bloating), whether there is a family or personal history of cancer (e.g. breast, ovarian or colorectal). A physical examination and blood tests are also needed to look for signs of pregnancy, infection, and other general illness or medical condition.
Then the next and best test if you have an ovarian cyst is an ultrasound scan. An ultrasound scan can provide useful information about the nature of an ovarian cyst. The signs of a benign cyst on ultrasound are: the cyst is thin-walled, has only one cavity (is unilocular), has a smooth border and is less than 10cm in diameter.
Medical studies have shown that cyst aspiration and medication with the combined contraceptive pill do not speed up the process of the cyst resolving.
If an ultrasound reveals a cyst which is complex and/or does not have benign features then it is vital to carry out a speedy and thorough investigation for ovarian cancer.
This answer is based on medical evidence obtained from good research studies.
Summary of the medical evidence
It is known that cysts in the ovaries are common. All women of child bearing age have simple follicular cysts at some time. The best initial test for obtaining a good image of an ovarian cyst is a high-frequency, transvaginal, gray-scale ultrasound examination.
The differential diagnosis includes: pregnancy, abscess of the ovary and/or fallopian tube, ruptured cyst, endometriosis, ectopic pregnancy, torsion of an ovary, and ovarian cancer.
It has been found that the risk of a woman developing a suspicious adnexal mass that needs surgical treatment during her lifetime is about 5-10 percent. Of those women who have surgery the perentage of women who turn out to have ovarian cancer is 13-21 percent.
Medical studies have looked at the risk of cancer in women who have thin-walled, single cavity, sonolucent (having a clear appearance with no echoes) ovarian cysts that are less than 10cm in diameter. The rate of malignancy was less than 1 percent – in both pre or post-menopausal women.
One study looked at 2,763 post-menopausal women with this type of cyst. The women had repeat ultrasound scans every 6 months for a mean of 6.3 years. None of the simple cysts became cancerous or turned out to be ovarian cancer. Nearly 70 percent of the cysts went away without treatment. The risk of cancer is less in pre-menopausal women.
Therefore serial ultrasounds is sufficient to follow and document the resolution of cysts with these ultrasound features. It is recommended that ultrasound scans should be performed every 4-6 weeks initially. If no worrying changes are noted then the frequency of scans can be reduced to every 3-6 months.
Research studies have shown that neither aspiration of an ovarian cyst, nor treatment with a combined oral contraceptive pill is of benefit in treating ovarian cysts. A Cochrane review of 500 women found that treatment with combined oral contraceptives did not speed up the resolution of functional cysts in any medical trial. It was found that most ovarian cysts resolved without treatment within a few menstrual cycles.
Evidence regarding complex ovarian cysts
Cysts that are found to be complex adnexal masses or those that persistent as thin-walled cysts should be evaluated for possible ovarian cancer.
Testing for cancer antigen (CA) 125 may be useful in women with these cysts, particularly in postmenopausal women.
In premenopausal women, benign conditions such as endometriosis can elevate CA 125 levels to more than 1,000 U per mL (1,000 kU per L).
Because of this, CA 125 measurement on it own is not sensitive or specific enough to determine ovarian cancer risk.
The risk of ovarian cancer algorithm analyzes changes in CA 125 levels to provide greater sensitivity and specificity than a single value alone.
However, only 50 percent of stage I epithelial cancers secrete CA 125 at the time of diagnosis. During the course of development, only 80 percent of ovarian cancers produce significant amounts of CA 125.
When combined with CA 125 measurement, biomarker HE4 increases the sensitivity by 22 percent and specificity by 90 percent.
A risk of malignancy index has been created using the following factors: menopausal status, ultrasound results, and CA 125 level in a single scale. The index has a sensitivity of 85 percent and specificity of 97 percent in determining the difference between benign and malignant pelvic masses.
Along with this ultrasound scans helps identify benign masses, whereas CA 125 measurement aids in identification of malignancies.
There is a U.K. Collaborative Trial of Ovarian Cancer Screening that is following more than 200,000 post-menopausal women over time. In this trial, a rising CA 125 level prompts a vaginal ultrasound scan.
Recommendations from Others
In July 2007, the American College of Obstetricians and Gynecologists published guidelines on the management of adnexal masses. These recommendations address the following: history, pelvic examination, ultrasonography, laboratory studies, and surgery.
In a woman with an ovarian cyst the medical history should include risk factors, such as older age, family history of breast or ovarian cancer, hereditary nonpolyposis colorectal cancer, Lynch II syndrome, nulliparity, primary infertility, and endometriosis. Performing a pelvic examination is limited in the identification of pelvic masses, but may identify distant metastasis.
High-frequency gray-scale transvaginal ultrasonography is recommended as the imaging modality of choice. Laboratory testing should include a full blood count, cervical cultures, and measurement of human chorionic gonadotropin (HCG), lipids including low-density lipoprotein cholesterol, and α-fetoprotein.
However, elevated CA 125 levels (greater than 200 U per mL (200 kU per L) in pre-menopausal women and greater than 35 U per mL (35 kU per L) in post-menopausal women) have the greatest positive predictive value (49 percent in pre-menopausal women and 98 percent in postmenopausal women).
Surgery using a laparoscope may be beneficial for evaluating and treating benign cysts, although it is laparoscopic surgery is contraindicated in patients with a high suspicion for ovarian cancer. These patients should be referred to a specialist gynecological oncologist for urgent assessment and treatment.
1. American College of Obstetricians and Gynecologists. ACOG Practice Bulletin. Management of adnexal masses. Obstet Gynecol. 2007;110(1):201–214.
2. Drake J. Diagnosis and management of the adnexal mass. Am Fam Physician. 1998;57(10):2471–2476.
3. Modesitt SC, Pavlik EJ, Ueland FR, DePriest PD, Kryscio RJ, van Nagell JR Jr. Risk of malignancy in unilocular ovarian cystic tumors less than 10 centimeters in diameter. Obstet Gynecol. 2003;102(3):594–599.
4. Grimes DA, Jones LB, Lopez LM, Schulz KF. Oral contraceptives for functional ovarian cysts. Cochrane Database Syst Rev. 2009;(2):CD006134.
5. DePriest PD, Shenson D, Fried A, et al. A morphology index based on sonographic findings in ovarian cancer. Gynecol Oncol. 1993;51(1):7–11.
6. Jacobs I, Oram D, Fairbanks J, Turner J, Frost C, Grudzinskas JG. A risk of malignancy index incorporating CA 125, ultrasound and menopausal status for the accurate preoperative diagnosis of ovarian cancer. Br J Obstet Gynaecol. 1990;97(10):922–929.
7. Kitawaki J, Ishihara H, Koshiba H, et al. Usefulness and limits of CA-125 in diagnosis of endometriosis without associated ovarian endometriomas [published correction appears in Hum Reprod. 2007;22(2):627]. Hum Reprod. 2005;20(7):1999–2003.
8. Skates SJ, Menon U, MacDonald N, et al. Calculation of the risk of ovarian cancer from serial CA-125 values for preclinical detection in postmenopausal women. J Clin Oncol. 2003;21(10 suppl):206s–210s.
9. National Institutes of Health Consensus Development Conference Statement. Ovarian cancer: screening, treatment, and follow-up. Gynecol Oncol. 1994;55(3 pt 2):S4–S14.
10. Brown AK, Moore RG, Miller MC, et al. A novel multiple biomarker assay for the detection of ovarian carcinoma. Paper presented at: 2006 American Society of Clinical Oncology Annual Meeting; June 2–6, 2006; Atlanta, Ga. Abstract 5023.
11. Menon U, Gentry-Maharaj A, Hallett R, et al. Sensitivity and specificity of multimodal and ultrasound screening for ovarian cancer, and stage distribution of detected cancers: results of the prevalence screen of the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS). Lancet Oncol. 2009;10(4):327–340.
12. Im SS, Gordon AN, Buttin BM, et al. Validation of referral guidelines for women with pelvic masses. Obstet Gynecol. 2005;105(1):35–41.