Case Study: Genetic Testing for Hereditary Breast Cancer

Abstract

Hereditary breast cancer accounts for a good proportion of breast cancer cases, including those associated with mutations in the BRCA1 and BRCA2 genes. This case study engages genetic testing as a tool in identifying patients with an elevated risk of hereditary breast cancer while providing timely intervention and reducing mortality rates. The patient case analysis makes it possible to ascertain the effectiveness of genetic counseling, diagnostic testing, and preventive interventions such as prophylactic surgery and follow-up examinations. This case is highly significant in identifying the role of genetic testing in managing and treating hereditary breast cancer not only from the patient's viewpoint but also in terms of clinical results.

Introduction

Hereditary breast cancers, primarily due to mutations of the BRCA1 and BRCA2 genes, represent 5–10% of all breast cancers. Women carrying such mutations will be at an increased lifetime risk of between 80% to even suffer from breast cancer, much higher than in the general population. There is a need for screening of such mutations so that women at such high risk can be identified and intervention started much earlier through such preventive approaches as enhanced screening, chemoprevention, and even prophylactic surgeries. This case study explores one 45-year-old patient who has underwritten a strong family history of breast cancer and the decisions that follow in the clinic.

Patient Information

• Patient: Jane Doe, 45-year-old female

• Family History: Mother and maternal aunt both diagnosed with breast cancer in their early 50s

• Presenting Concerns: The patient was concerned about her genetic risk of developing breast cancer due to her family history and sought genetic counseling.

Clinical Findings

During the genetic counseling session, the history of breast cancer in the patient's family was taken and discussed with the individual regarding her risks. Based on her family history, the patient's counselor advised on genetic testing for BRCA1 and BRCA2 mutations. The results of the patient's genetic test came out positive for a pathogenic mutation of BRCA1 with high predictive values for having a high predisposition to breast cancer.

Timeline

1. Day 0: Patient meets with a genetic counselor to discuss family history.

2. Day 10: Genetic testing for BRCA1 and BRCA2 is conducted.

3. Day 30: Test results confirm a BRCA1 mutation.

4. Day 35: The patient is informed about preventive care options, including enhanced screening and prophylactic surgery.

5. Day 60: Patient decides to undergo a prophylactic bilateral mastectomy.

6. Day 120: Surgery is completed successfully with no complications.

7. Follow-Up (6 months later): Patient remains healthy, with no signs of breast cancer. Continued surveillance is planned.

Diagnostic Assessment

In this case, the genetic testing for mutations of BRCA1 and BRCA2 was applied. From the positive result to the BRCA1 mutation, the patient was counseled on the possibilities available for the management of her risk for increased breast cancer. No clinical signs of existing cancer were found in mammography or MRI imaging.

Follow-Up and Outcomes

After genetic testing and affirmation of the BRCA1 mutation, the patient elected to have a prophylactic bilateral mastectomy to minimize her risk of breast cancer. The mastectomies were successful in significantly reducing this woman's risk of developing breast cancer. Care continued at regular intervals through checkups, physical exams, and risk discussions over ovarian cancer, which is also increased in mutation carriers with BRCA.

She was doing well, relieved by her decision to be proactive, and was committed to ongoing surveillance for ovarian cancer and any other abnormalities associated with her genetic mutation at follow-up.

Discussion

Genetic testing for hereditary breast cancer provides patients with a significant family history with a critical possibility of determining early their risk and taking measures to minimize it. In this case, early detection of the mutation in BRCA1 made it possible to intervene in time with prophylactic bilateral mastectomy, an action that effectively brought the patient's risk of acquiring breast cancer down to almost 90%.

The majority of the genetics tests were based on concerns over family history and the availability of genetic counseling services. Because the genetic counselor provided accurate information to help the patient make care decisions, she was able to consider all risk-reduction options after testing positive for a BRCA1 mutation-including enhanced screening and chemoprevention chose surgery as the most definitive strategy.

This case, therefore, underlines the importance of genetic testing for both those who have a powerful family history and also for potentially affected family members. Genetic testing means other family members who might be carrying the mutation get a chance to assess their risk and take preventive measures as well. The case also explains how genetic counseling can assist patients in processing their decision-making process and make sure that a patient has access to resources that would help them manage their risks appropriately.

Takeaway

This case illustrates the importance of genetic testing for hereditary breast cancer by taking the risk assessment profiles of patients to a personalized level and giving them specific preventive measures. For patients such as this patient, genetic testing may provide life-saving information that leads to early interventions and lesser risks of developing cancer. Patients with a history of breast cancer in their family should be assessed for candidacy through genetic counseling. In the current case, the selected technique of risk reduction- prophylactic bilateral mastectomy for the given patient- is useful for demonstrating the empowerment that genetic testing offers patients in making choices related to their health.

Patient’s Perspective

The patient found relief and appreciation in knowing the presence of the BRCA1 mutation and then taking measures to prevent it. "I was very apprehensive about my family history, but knowing my genetic status helped me plan. It was a big decision, but surgery was reassuring," she said. She also benefitted from support throughout her journey; she admitted that her genetic counselor and surgical team clearly and helpfully coached her.

Conclusion

Genetic testing for hereditary breast cancer plays a crucial role in designing programs for screening and determining the necessity of protection measures. In this patient's case, she had herself tested for BRCA 1 gene mutation, which helped her intervene in time through a prophylactic bilateral mastectomy; thereby the chances of contracting breast cancer were negated completely to a great extent. This case makes one realize the significance of genetic counseling and illustrates the issue with complex risk assessment as well as preventive care options for a patient.

For instance, it would be crucial for a patient with a strong family history of breast cancer. Genetic testing empowers and gives control to patients' lives through choices that reduce their risk in addition to enabling them to do so. The case shows how even a straightforward genetic test, combined with preventive measures such as surgery or enhanced screening, can help decrease the incidence of cancer and quality-of-life deterioration in at-risk patients.

The case ultimately casts light on the issue of prompt detection, prevention, and tailored medicine in the management of hereditary breast cancer and presents a way to reduce emotional and physical suffering due to this disease. It is indispensable to include genetic testing in the core approach for those with a family history of breast cancer because it may drastically alter the management course and outcomes in patients with such cancer.

References

1. Mavaddat, N., et al. (2013). Prediction of breast cancer risk based on profiling with common genetic variants. Journal of the National Cancer Institute, 105(17), 1299-1308.

2. King, M. C., et al. (2003). Breast and ovarian cancer risks due to inherited mutations in BRCA1 and BRCA2. Science, 302(5645), 643-646.

3. Metcalfe, K. A., et al. (2008). Effect of prophylactic mastectomy on breast cancer risk in women with BRCA1 and BRCA2 mutations. Journal of Clinical Oncology, 26(8), 1093-1097.

4. Nelson, H. D., et al. (2019). Genetic risk assessment and BRCA mutation testing for breast and ovarian cancer susceptibility: Updated evidence report and systematic review for the US Preventive Services Task Force. JAMA, 322(7), 666-685.

5. Kuchenbaecker, K. B., et al. (2017). Risks of breast, ovarian, and contralateral breast cancer for BRCA1 and BRCA2 mutation carriers. JAMA, 317(23), 2402-2416.

6. Daly, M. B., et al. (2021). NCCN guidelines insights: Genetic/familial high-risk assessment: Breast, ovarian, and pancreatic, version 1.2020. Journal of the National Comprehensive Cancer Network, 18(4), 380-391.

7. Kuchenbaecker, K., et al. (2014). Risks of breast, ovarian, and contralateral breast cancer for BRCA1 and BRCA2 mutation carriers. JAMA, 317(23), 2402-2416.

8. Evans, D. G., et al. (2009). A new scoring system for the cancer genetic clinic referral of women with a family history of breast cancer: Evaluating the Manchester scoring system. Family Cancer, 8(1), 49-56.

9. Domchek, S. M., et al. (2010). Association of risk-reducing surgery in BRCA1 or BRCA2 mutation carriers with cancer risk and mortality. JAMA, 304(9), 967-975.

10. Tung, N., et al. (2016). Frequency of mutations in individuals with breast cancer referred for BRCA1 and BRCA2 testing using next-generation sequencing with a 25-gene panel. Cancer, 122(1), 42-49.

11. Chen, S., & Parmigiani, G. (2007). Meta-analysis of BRCA1 and BRCA2 penetrance. Journal of Clinical Oncology, 25(11), 1329-1333.

12. Antoniou, A., et al. (2003). Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case series unselected for family history: A combined analysis of 22 studies. American Journal of Human Genetics, 72(5), 1117-1130.

Read more such content on @ Hidoc Dr | Medical Learning App for Doctors