When evaluating the use of an imaging modality for screening, an important metric to consider is positive predictive value (PPV), which is defined as the number of true-positive cases divided by the total number of test- positive cases. Unlike the sensitivity and specificity of a diagnostic test, PPV incorporates both test performance and disease prevalence. A minimum PPV of 10% has been suggested as necessary for an ovarian cancer screening tool [9,12]. This implies that at least one cancer should be diagnosed in every 10 patients who undergo salpingo- oophorectomy for suspicion of malignancy. Given the low prevalence of ovarian cancer, very high specificity is needed for a successful screening tool. At an assumed prevalence of one case per 2,500 postmenopausal women per year, a test with perfect sensitivity (100%) would require a specificity of 99.6% to achieve a 10% PPV, and a test with 50% sensitivity would require an even higher specificity of 99.8% [9,12-14]. Discussion of Procedures by Variant Variant 1: Ovarian cancer screening. Premenopausal. Average risk. To our knowledge, the relevant literature on ovarian cancer screening in average-risk women is limited to studies in postmenopausal women. US There is currently no evidence to support the use of US or color Doppler for ovarian cancer screening in premenopausal women without risk factors. Most studies discussed in this document have addressed the use of transvaginal US. In general, transabdominal US should be reserved for women in whom transvaginal US is not technically feasible, or used as a complement to transvaginal US. CT There is currently no evidence to support the use of CT for ovarian cancer screening in premenopausal women without risk factors. MRI There is currently no evidence to support the use of MRI for ovarian cancer screening in premenopausal women without risk factors.
Ovarian Cancer Screening. When evaluating the use of an imaging modality for screening, an important metric to consider is positive predictive value (PPV), which is defined as the number of true-positive cases divided by the total number of test- positive cases. Unlike the sensitivity and specificity of a diagnostic test, PPV incorporates both test performance and disease prevalence. A minimum PPV of 10% has been suggested as necessary for an ovarian cancer screening tool [9,12]. This implies that at least one cancer should be diagnosed in every 10 patients who undergo salpingo- oophorectomy for suspicion of malignancy. Given the low prevalence of ovarian cancer, very high specificity is needed for a successful screening tool. At an assumed prevalence of one case per 2,500 postmenopausal women per year, a test with perfect sensitivity (100%) would require a specificity of 99.6% to achieve a 10% PPV, and a test with 50% sensitivity would require an even higher specificity of 99.8% [9,12-14]. Discussion of Procedures by Variant Variant 1: Ovarian cancer screening. Premenopausal. Average risk. To our knowledge, the relevant literature on ovarian cancer screening in average-risk women is limited to studies in postmenopausal women. US There is currently no evidence to support the use of US or color Doppler for ovarian cancer screening in premenopausal women without risk factors. Most studies discussed in this document have addressed the use of transvaginal US. In general, transabdominal US should be reserved for women in whom transvaginal US is not technically feasible, or used as a complement to transvaginal US. CT There is currently no evidence to support the use of CT for ovarian cancer screening in premenopausal women without risk factors. MRI There is currently no evidence to support the use of MRI for ovarian cancer screening in premenopausal women without risk factors.