A 30-year-old woman of Indian descent presented with a family history of various cancers including breast, thyroid, and stomach. Her mother was found to be affected with thyroid cancer, and soon after with breast cancer, both of which have been treated (by medication and surgery respectively) and she is now in remission.
The consultant has a personal history of breast lumps (past four years) and two irregular pap-smears. A cone-biopsy was performed and the precancerous cells were removed following the first one. There was no treatment performed after the second irregular pap-smear and she was under observation until the next papsmear scheduled within six months.
She had already had the BRCA1 and BRCA 2 genetic testing done which identified three variants of unknown significance (VUS) and no pathogenic (disease-causing) mutations.
*VUS – A variation in the genetic sequence whose association with disease risk is unknown and thus cannot be classified as either diseasecausing or benign.
Purpose of consultation:
- To interpret the BRCA 1 and 2 genetic test reports and to understand the implications of the results for herself.
- To devise a management and surveillance plan with her breast specialist based on the genetic test results.
Summary of counseling:
Given that the consultant herself hadn’t been affected with breast cancer, the BRCA 1 and 2 test reports did not provide much insight to the presence of any disease-causing mutations that might be present in the family. I thus advised that her mother undertake the same test as she had been affected with breast cancer and there were higher chances of finding the disease-causing mutation, if any, in her. Following our appointment, her mother also took the BRCA 1 and 2 tests and there were no known pathogenic mutations identified. However, there was one VUS detected in the BRCA 2 gene which was the same as in the consultant, and is classified in the literature as “quite likely pathogenic”. This VUS could
thus be the cause of breast cancer in the family.
We could offer the same genetic test to other members of the family to further establish the role of this VUS in this family. However, until more information can be gathered regarding this VUS, I recommended that the consultant follow the same breast and ovarian surveillance guidelines as those offered to an individual with moderate increase in risk of breast cancer.
Breast cancer refers to a malignant tumor that has developed in the cells of the breast.
Hereditary Breast and Ovarian Cancer (HBOC) is inherited in an autosomal dominant manner. The vast majority of individuals with a BRCA1 or BRCA2 pathogenic variant have inherited it from a parent. Each offspring of an individual with a BRCA1 or BRCA2 germline pathogenic variant has a 50 percent chance of inheriting the variant.
The surveillance plan would include:
- Practice breast self-examination and seek medical advice if she detects any changes,
- Having a clinical examination every six months
- Have screening mammograms every two years
Since there may also be an increased risk of developing ovarian cancer, it is also recommended that she carry out ovarian surveillance, consisting of an internal (‘transvaginal’) ultrasound every year from the age of 40.
The same recommendations and the consultation summary were conveyed to her primary care physician and breast specialist via a genetic counseling summary letter.