According to results recently published in Gynecologic Oncology, transvaginal sonography (TVS) is significantly more accurate in defining the dimensions of ovaries (an important identifier of ovarian cancer) than pelvic examination, particularly in older women who are overweight or have increased uterine weight.
Ovarian cancer is one of the most deadly gynecologic cancers because it tends to be diagnosed at a late stage (once the cancer has spread); it is thus difficult to cure. Patients may not notice symptoms of early-stage ovarian cancer, which can include vague sensations such as bloating, constipation, diarrhea, and/or abdominal pain. If detected and treated prior to spread, ovarian cancer may be cured with standard therapies. Thus, early detection is a necessary part of improving outcomes for patients diagnosed with this disease.
One identifying factor of ovarian cancer is a change in dimensions of the ovary. Unfortunately, the pelvic examination typically performed during routine visits to the gynecologist is not highly accurate in detecting ovarian cancers in earliest stages. Therefore, there is a need for ovarian cancer screening methods that are accurate, yet affordable and efficient.
Transvaginal sonography includes the use of ultrasound to provide pictures of the ovaries. Although prohibitively costly and time-consuming for widespread use at present, transvaginal sonography may be a useful screening method for patients at high risk of developing ovarian cancer or for those for whom pelvic examinations provide few meaningful results.
Researchers from the University of Kentucky Medical Center conducted a clinical trial to compare the accuracy of a pelvic examination with transvaginal sonography. The ovaries of 151 women were evaluated. Women underwent anesthesia, a complete pelvic examination, and TVS. The ovaries of the women were then surgically removed. Measurements of the ovaries removed from surgery were compared to those from pelvic examination and TVS. TVS produced more accurate results:
- Only 44% of ovaries were palpable (physicians could detect them) with pelvic examination, whereas 85% of ovaries were able to be visualized through TVS.
- Ovaries were detected on pelvic examination in only 9% of women who weighed 200 pounds or greater versus 55% of women weighing less than 200 pounds.
- Ovaries were detected on pelvic examination in only 30% of women 55 years or older, compared with 51% of women older than 55 years.
- Ovaries were detected on pelvic examination in only 12% of women whose uterus weighed 200 grams or greater versus 51% of women with a uterine weight of less than 200 grams.
- TVS was significantly more accurate than pelvic examination in detecting ovaries in women who were overweight, over 55 years of age, or those who had a higher uterine weight.
The researchers concluded that TVS significantly improves the rate of ovarian detection over pelvic examination, particularly in women who are overweight, those who are 55 years or older, and those with a greater uterine weight. These results may also be cautiously applied to women without these characteristics since overall detection rates of ovaries were significantly improved with TVS or pelvic examination. However, further studies are necessary to determine the ultimate benefit of TVS in women with specific characteristics.
TVS may ultimately provide improved screening for women who are at an increased risk of developing ovarian cancer. Women at an increased or those who are overweight and over the age of 55 years may wish to speak with their physician regarding their individual risks and benefits of TVS as a screening procedure.
Reference: Ueland F, DePriest P, DeSimone C, et al. The accuracy of examination under anesthesia and transvaginal sonography in evaluating ovarian size. Gynecologic Oncology. 2005;99: 400-403.