Could an Emerging Classification Scheme Streamline Ovarian Cancer Detection on Pelvic Ultrasound?

While there are multiple risk stratification schemes for assessing adnexal lesions on ultrasound, the authors of a new simplified classification system suggest it may provide a more efficient triage measure. In essence, differentiating between classic and non-classic presentations of adnexal lesions on ultrasound may prevent unnecessary additional workup of classic benign lesions and facilitate further workup and timely referrals for women with non-classic lesions, according to the recently published study in Radiology.

In a retrospective multicenter study, the authors assessed the use of an ultrasound classification system to determine whether patients had classic benign lesion presentations or non-classic lesions that warranted further workup or treatment. According to the study, the authors noted that classic benign presentations included mature cystic teratomas, endometriomas, hemorrhagic cysts and simple cysts. Non-classic presentations included adnexal lesions with solid components or multiple septations.

Assessing 970 isolated adnexal lesions in 878 women with a mean age of 42, the study authors found that the simplified ultrasound classification scheme had a sensitivity rate of 93 percent and a specificity rate of 73 percent for detecting ovarian cancer.

“Existing (classification) systems have multiple subcategories but are based on a common premise: Classic benign-appearing lesions have a very low risk for cancer, whereas non-classic lesions have a higher risk for cancer. This classic-versus-non-classic approach to isolated adnexal lesions could be helpful to radiologists in a busy clinical practice so that they can more quickly assess a lesion and recommend management,” wrote Akshya Gupta, MD, who is affiliated with the Department of Imaging Sciences at the University of Rochester Medical Center in New York, and colleagues.

Noting a less than 1 percent malignancy rate for the classic lesions in the study, the study authors found an 8 percent malignancy rate for non-classic lesions with no blood flow and a 32 percent malignancy rate for non-classic lesions with blood flow. For women older than 60 years of age, Dr. Gupta and colleagues noted a 50 percent malignancy rate in cases involving non-classic lesions with blood flow, according to the study.

“By stratifying lesions into classic and non-classic categories, radiologists can opt to follow the simplified recommendations from Gupta et al. They can reassure women with classic lesions that the likelihood of the lesion being malignant is extremely low, perform MRI or follow-up (ultrasound) for non-classic lesions without blood flow, and refer women with non-classic lesions with blood flow (especially in women older than 60 years) to a gynecologic oncologist,” wrote Deborah A. Baumgarten, MD, MPH, a professor of abdominal radiology at the Mayo Clinic in Jacksonville, Fla., in an accompanying editorial.

Acknowledging a lack of patient follow-up and the potential for selection bias inherent to a retrospective study, the study authors also noted that imaging protocols, device settings and image archiving were not standardized across the institutions that participated in the study. Dr. Gupta and colleagues also pointed out that the majority of women in the study were premenopausal, which would preclude extrapolation of the study findings to populations at higher risk for ovarian cancer.