CASE Young woman with family history of breast cancer detects lump
Two weeks after noting a lump on her breast when her cat happened to jump on her in that spot, a 28-year-old woman (G0) went to her primary care provider. She was referred to her gynecologist; breast imaging, ultrasonography, and mammography were obtained, with microcalcifications noted. A fine needle aspiration diagnosed intraductal malignancy. The surgical breast tissue specimen was estrogen receptor (ER)- and progestogen receptor (PR)-positive and HER2-negative. Other tumor markers were obtained, including carcinoembryonic antigen, and tissue polypeptide specific antigen, p53, cathepsin D, cyclin E, and nestin, but results were not available.
With regard to family history, the woman’s mother and maternal grandmother had a history of breast cancer. The patient and her family underwent gene testing. The patient was found to be BRCA1- and BRCA2-positive; her mother was BRCA1-positive, an older sister was BRCA2-positive, and her grandmother was not tested.
The question arose in light of her family history as to why she was not tested for BRCA and appropriately counseled by her gynecologist prior to the cancer diagnosis. Litigation was initiated. While the case did not go forward regarding litigation, it is indeed a case in point. (Please note that this is a hypothetical case. It is based on a composite of several cases.)
Breast cancer is the most common type of cancer affecting women in the Western world.1 Advances in clinical testing for gene mutations have escalated and allowed for identification of patients at increased risk for breast and ovarian cancer. Along with these advances come professional liability risk. After looking at the medical considerations for BRCA1 and 2 testing, we will consider a number of important legal issues. In the view of some commentators, the failure to diagnose genetic mutations in patients predisposed to cancer is “poised to become the next wave of medical professional liability lawsuits.”2
BRCA1 and BRCA2 genes provide tumor suppressor proteins, and assessment for mutations is recommended for individuals at high risk for breast and/or ovarian cancer; mutations in BRCA genes cause DNA damage, which increases the chance of developing cancer. The other way to look at it is, BRCA1 and 2 are tumor suppressor genes that are integrally involved with DNA damage control. Once there is a mutation, it adversely affects the beneficial effects of the gene. Mutations in these genes account for 5% to 10% of all hereditary breast cancers.3 Of note, men with BRCA2 are at increased risk for prostate cancer.
A patient who presents to her gynecologist stating that there is a family history of breast cancer, without knowledge of genetic components, presents a challenge (and a medicolegal risk) for the provider to assess. Prediction models have been used to determine specific patient risk for carrying a genetic mutation with resultant breast cancer development.4 Risk prediction models do not appear to be a good answer to predicting who is more likely to develop breast or ovarian cancer, however. A Mayo model may assist (FIGURE).5 Clinicians should also be aware of other models of risk assessment, including the Gail Model (TABLE 1).6
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