TOPLINE

Women with pathogenic variants (PVs) in BRCA1/2 genes were more than seven times as likely to undergo risk-reducing mastectomy (RRM) and risk-reducing salpingo-oophorectomy (RRSO) as were those carrying genetic variants for which there is “insufficient evidence” for discussion, consideration, or recommendation related to use of either procedure for such patients. Pancreatic screening via endoscopic ultrasound (EUS) or magnetic resonance cholangiopancreatography (MRCP) was used by fewer than 11% of eligible women, regardless of gene type, within 12 months after genetic testing.

METHODOLOGY

• In the study, in cancer-free women, genes were grouped as BRCA1/2, non-BRCA1/2 guideline-indicated (use to be discussed, considered, or recommended), or insufficient evidence, on the basis of the National Comprehensive Cancer Network guidelines, for RRM, RRSO, and EUS/MRCP. For breast MRI, genes were grouped as BRCA1/2 or non-BRCA1/2 guideline-indicated (use recommended or considered).
• Researchers conducted a cross-sectional study of 3959 women (2088 cancer-free and 1871 with primary breast cancer) who had PVs in at least one of 13 breast cancer susceptibility genes identified through germline panel testing at a commercial laboratory in the US between 2015 and 2023. Participants had at least 12 months of continuous healthcare claims data before and after genetic testing, with an average age at testing of 45 years; 67% were White, and 90% reported having a family history of cancer.
• Analysis evaluated utilization of RRM, RRSO, breast MRI, and pancreatic screening (MRCP or EUS) during the 12 months following genetic testing using Current Procedural Terminology codes, the Healthcare Common Procedure Coding System, and the National Drug Code.
• Multivariable logistic regression models assessed associations between clinicodemographic factors (age, race or ethnicity, family history, insurance type, and geographic region) and genetic testing results with intervention utilization.

TAKEAWAY

• Cancer-free women with BRCA1/2 PVs had higher odds of RRM (odds ratio [OR], 7.2), RRSO (OR, 7.2), and breast MRI (OR, 2.6) than did those with insufficient evidence gene PVs.
• Women with breast cancer and BRCA1/2 PVs demonstrated increased odds of RRM (OR, 6.0), RRSO (OR, 13.8), and EUS/MRCP (OR, 2.5) compared with those with insufficient evidence gene PVs.
• Among cancer-free women, those with non-BRCA1/2 guideline-indicated gene PVs had higher odds of RRSO (OR, 3.9) and EUS/MRCP (OR, 3.6) than did those with insufficient evidence gene PVs.
• Women with a family history of pancreatic cancer had higher odds of undergoing EUS/MRCP (OR, 5.1 for cancer-free; OR, 2.7 for those with cancer) than did those without such a family history.

IN PRACTICE

“Utilization of risk-reducing surgery was highest in women with BRCA1/2 PV. Pancreatic screening was low in all patients. Future studies are needed to examine the factors underlying these trends,” wrote the authors of the study.

SOURCE

The study was led by Emily M. Russell, PhD, and Sarah M. Nielsen, MS, of Labcorp in San Francisco. It was published online on August 26 in JCO Precision Oncology.

LIMITATIONS

According to the authors, the study used a cross-sectional design analyzing patients referred for clinical genetic testing over nearly a decade during which guidelines evolved, potentially affecting intervention patterns. The number of patients with continuous claims data for ≥ 2 years after genetic testing was relatively low, limiting longer-term trend analysis. For some genes including CDH1, PTEN, and STK11, PVs were rare and data were limited. Researchers lacked information about patient preferences, clinician recommendations, tumor biomarkers and somatic mutations, and complete demographic and family history information, which influence intervention timing and utilization. Real-world data limitations created ambiguities in differentiating between breast MRI use for screening and diagnosis or monitoring purposes.

DISCLOSURES

Labcorp (formerly Invitae Corporation) provided support for the study. Russell disclosed employment and stock ownership with Invitae and Labcorp. Nielsen disclosed employment, stock ownership, and travel expenses from Invitae and Labcorp. Allison W. Kurian, MD, MSc, reported uncompensated relationships with multiple organizations including Ambry Genetics, Color Genomics, GeneDx/BioReference, Invitae, Genentech, Myriad Genetics, Adela, Merck, Gilead Sciences, and Foundation Medicine. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.