The value of a negative genetic result when triaging an adnexal mass.

Abstract

e17553 Background: The baseline risk for ovarian cancer in the general population is 1.2%1. However, women with germline variants in ovarian cancer-associated genes can have a much higher baseline risk for ovarian cancer, up to 54%2. Such a difference in baseline risk presents a triaging challenging for physicians when evaluating adnexal masses. It is well known that identifying pathogenic variants in hereditary cancer syndrome genes often leads to changes in care. Less is known about the utility of negative genetic testing results, specifically in the context of adnexal mass assessment. Methods: An observational, prospective study was designed to examine the clinical impact of multivariate index assay (MIA) and germline genetic testing in patients with a known adnexal mass planned for surgery. Inclusion criteria were: female subjects aged 18-65, presence of an adnexal mass, receiving MIA, and consideration of germline genetic testing. Enrolled physicians selected patients under their care that met inclusion criteria and filled out a short survey describing how the results of each test impacted clinical management. This study was considered IRB-exempt as all information was de-identified. Results: 23 patients were enrolled that received both MIA and germline genetic testing. 21 cases had negative genetic testing and two had positive genetic testing. Both patients with positive genetic testing had low-risk MIA results. Both had risk-reduction surgery with benign findings. Three patients had high-risk MIA results with negative genetic results. All patients had a serial monitoring plan of care. Nine patients with low-risk MIA results and negative genetic results proceeded to surgery. No malignancies were reported. Of the 21 patients with negative genetic results, 17 were not immediately planned for surgery. Conclusions: While not reaching statistical significance, there is a strong association between a negative genetic result and non-immediate surgical intervention. While positive genetic testing results may lead to more aggressive, prophylactic surgical management, negative genetic results may support an expectant management approach. Effectively ruling out the most common hereditary cancer predisposition syndromes may provide physicians with useful insight into a patient's baseline risk. [Table: see text]