Allison W. Kurian, MD, MSc from Stanford University California speaks about Genetic Testing for Breast and Ovarian Cancer: What Has Changed and What Still Needs To Change?
Link to Article:
https://www.medscape.com/viewarticle/947040
A major retrospective review illustrates how germline genetic testing in women with breast or ovarian cancer has progressed over time, as well as a way forward for testing these patients.
Researchers discovered racial and ethnic differences in genetic testing, as well as “persistent underuse” of testing in ovarian cancer patients.
The researchers also discovered that the majority of pathogenic variant (PV) findings came from 20 genes linked to breast and/or ovarian cancer, while testing other genes mostly showed variants of unknown significance (VUS).
The results were published in the Journal of Clinical Oncology by Allison W. Kurian, MD, of Stanford (Calif.) University and colleagues.
Genetic testing has become more accessible to clinicians for patient management and cancer prevention as sequencing technology has improved, competition among commercial purveyors has increased, and costs have decreased (JAMA. 2015 Sep 8;314[10]:997-8). While germline testing can help direct treatment for a variety of solid tumors, little research has been done about how often and how well it is used in practice.
Kurian and colleagues conducted a population-based evaluation of cancer risk testing using a SEER Genetic Testing Linkage Demonstration Project. From 2013 to 2017, the researchers looked at 7-year trends in testing for all women diagnosed with breast or ovarian cancer in Georgia or California, looking at testing patterns and outcome perception from 2012 to 2019.
The investigators made the following hypotheses before analyzing the data:
Multigene panels (MGP) will fully replace BRCA1/2 testing.
Over time, testing underutilization of ovarian cancer patients will increase.
More patients will be screened for PVs at lower pre-test risk levels.
* There will be no sociodemographic variations in research patterns.
* PV and VUS detection will improve.
* Racial and ethnic inequalities in VUS rates will be reduced.
Conduct of the Research
The researchers looked at genetic tests conducted at major commercial laboratories from 2012 to the beginning of 2019 and compared them to data from the SEER registries in Georgia and California on all breast and ovarian cancer patients diagnosed between 2013 and 2017. There were just a few exclusionary conditions.
The American College of Medical Genetics classified the findings of genetic testing as defining a PV or probable PV, VUS, or benign or likely benign mutation. The most recent procedure was used when a patient had genetic testing on more than one occasion.
If a PV was found, the types of PVs were classified into the following groups based on the degree of evidence supporting pathogenicity:
* Mutations in BRCA1 or BRCA2.
* PVs in other genes linked to breast or ovarian cancer, according to the National Comprehensive Cancer Network (e.g., ATM, BARD1, BRIP1, CDH1, CHEK2, EPCAM, MLH1, MSH2, MSH6, NBN, NF1, PALB2, MS2, PTEN, RAD51C, RAD51D, STK11, and TP53).
* PVs of other genes that can be acted upon (e.g., APC, BMPR1A, MEN1, MUTYH, NF2, RB1, RET, SDHAF2, SDHB, SDHC, SDHD, SMAD4, TSC1, TSC2, and VHL).
* Some other genes that have been studied.