NEW YORK (Reuters Health) – The results of the largest ovarian cancer screening trial to date suggest that a transvaginal ultrasound strategy or a multimodal approach that includes CA125 testing and ultrasound are both effective in detecting early-stage disease.
In the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) trial, 202,638 postmenopausal women were randomized to receive no ovarian cancer screening or screening with the multimodal strategy or ultrasound alone.
With the multimodal approach, CA125 testing was performed annually and women found to have an intermediate or high risk of ovarian cancer were referred for transvaginal ultrasound. With the ultrasound only approach, by contrast, ultrasound was performed in all women annually.
The results are reported in the March 10th Online First issue of The Lancet Oncology.
Primary ovarian cancers and tubal cancers were detected in 42 women in the multimodal screening group and in 45 women screened by ultrasound alone. Of the 58 invasive cancers, 28 (43%) were stage I/II, lead author Dr. Usha Menon, from University College London, and colleagues report.
In detecting primary ovarian and tubal cancers, the multimodal approach yielded a sensitivity of 89.4%, a specificity of 99.8%, and a positive-predictive value of 43.3%. With the annual ultrasound strategy, the corresponding values were 84.9%, 98.2%, and 5.3%.
In detecting primary invasive epithelial ovarian and tubal cancers, the multimodal approach was associated with a sensitivity of 89.5%, a specificity of 99.8%, and a positive-predictive value of 35.1%. With the annual ultrasound strategy, the corresponding values were 75.0%, 98.2%, and 2.8%%.
With the exception of significantly higher specificities with the multimodal approach, the two screening strategies were comparable in their ability to detect ovarian and tubal malignancies.
The higher specificity with the multimodal approach resulted in lower rates of repeat testing and surgery, the authors note. This is due, at least in part, to ultrasound detecting more benign adnexal abnormalities and borderline tumors.
This study has established the feasibility of screening strategies of ovarian cancer, Dr. Menon and colleagues conclude. “The results of ongoing screening are awaited so that the effect of screening on mortality can be determined.”
Lancet Oncol 2009.