Mar 05, 2019
By Yanin Chávarri-Guerra, MD, MSc, with Charité Ricker, MS, CGC
Access to genetic cancer risk assessment and genetic testing in Latin America and the Caribbean is limited. However, both are critical components of appropriate clinical management for many patients with cancer, and the standard of care for most young patients diagnosed with breast cancer in the United States. Improving access to these very important interventions can be a challenge, but international collaboration is a potential solution, as I recently learned with one of my patients.
I first met Lily in July 2018 when she came into my office at Instituto Nacional de Ciencias Médicas y Nutricion Salvador Zubirán in Mexico City asking for help. Lily is a 7-year breast cancer survivor who was diagnosed with stage III triple-negative breast cancer when she was 38. She was treated with chemotherapy followed by mastectomy and adjuvant radiotherapy at a public cancer center in Mexico City, where she has been undergoing surveillance ever since. Even though Lily met the criteria for genetic counseling and testing, the lack of resources had prevented her from obtaining these services.
The day we met, Lily brought a letter in Spanish that said her sister Rosa, a Mexican immigrant living in Los Angeles, had been found to carry a pathogenic BRCA mutation. The letter recommended that Rosa’s family members get genetic counseling and testing in Mexico, and my name was listed in the contact information. The letter was written by Charité Ricker, a bilingual genetic counselor at the University of Southern California (USC), who counsels patients at Los Angeles County Medical Center + USC (LAC+USC), one of the largest public hospitals in the United States. Charité and I met during the year of training that I spent at City of Hope with Dr. Jeffrey Weitzel in the Division of Cancer Genomics. I took the Intensive Course in Cancer Risk Assessment and now I am part of the Clinical Cancer Genomic Community of Practice (CCGCoP), a large research group of more than 40 collaborating institutions from the United States and Latin America. Charité, who is part of the Intensive Course faculty, had asked if I would be willing to have my contact information provided to her patients in Los Angeles who had at-risk family members in Mexico, which is how Lily had found her way to me.
On the other side of the border, Lily’s sister, Rosa, had received genetic counseling with Charité at LAC+USC, after her primary care nurse practitioner had ordered BRCA testing. Although she did not have a personal history of cancer, her results came back positive for a pathogenic mutation in the BRCA2 gene. Rosa was then referred to Charité to discuss the impact of those results for her and her family members. Her risks for breast and ovarian cancer were estimated using several models, which approximated her lifetime risk for breast cancer to be 45% to 68% and her lifetime risk for ovarian cancer to be 27% to 36%. Rosa also received counseling on how to manage her cancer risk, including risk-reducing surgeries, enhanced cancer screening, and/or chemoprevention. Most importantly, the counselor discussed with Rosa the importance of informing the rest of her family about her results, since they could also carry the mutation. When her family heard the news, they became very concerned, as Rosa had told them they could have a 50% chance of having inherited the mutation and that they should be tested.
In my office, Lily was very distressed for her family. In addition to her own diagnosis, two of her sisters had passed away from breast and lung cancer at ages 33 and 58, respectively, and now she knew that this could be a consequence of the mutation. I offered Lily genetic counseling, and she and her siblings were able to get free genetic testing through a family testing program offered by the United States-based laboratory that identified Rosa’s mutation. Not surprisingly, Lily’s results also came back positive for BRCA2 mutation, and she is scheduled to undergo risk-reducing salpingoophorectomy and contralateral mastectomy. Back in Los Angeles, Rosa is also scheduled for a risk-reducing salpingoophorectomy, and has had both an MRI and mammogram. She is undecided about risk-reducing mastectomy, but will be meeting with her surgeons to discuss further. Her three children, all in their 20s, underwent genetic testing and were not found to carry the family mutation. To date, more than 10 of Rosa and Lily’s relatives have undergone cascade testing, most at no cost, either through a research collaboration with City of Hope or Rosa’s laboratory. As their results continue to come back, we will offer appropriate cancer screening and risk-reducing interventions for those found to carry the known family mutation.
Cancer is the third leading cause of death worldwide. It is estimated that one in six women worldwide will develop cancer during her lifetime and one in eleven will die from the disease. Cancer doesn´t respect national borders, walls, social class, or economic status. However, cancer outcomes are driven mainly by access to health care. Breast cancer incidence to mortality ratios in low- and middle-income countries, such as Mexico, are higher when compared to those in high-income countries, which in part is due to a higher incidence of advanced disease at presentation. The advancement of genetic research and technologies provides new possibilities for cancer screening, prevention, and earlier treatments. However, identification of patients at elevated risk for cancer requires resources that are beyond the reach of many communities around the world. Even within the United States, disparities in accessing genetic testing persist and are amplified in patients from diverse racial and ethnic backgrounds.
Access to cancer genetic risk assessment is limited in Latin American countries due to a lack of personnel and specialized resources. However, collaboration across borders can improve access to care for underserved patients in resource-limited settings, as Lily’s case clearly shows. At the same time, collaboration can also lead to advances in the understanding of issues facing immigrant populations living in high-resource countries, and thus to an improvement in health care provisions. Building bridges between clinicians and patients living across borders is therefore an incredibly powerful tool that can lead to better care, innovation, and more cancer cures.
Rosa and Lily are part of a highly motivated family who show us what can be accomplished when clinicians and patients work together, despite limited resources and national borders. Charité and I will continue to work together, so that more of these families with mutations in cancer predisposition genes identified in the United States can access counseling and genetic testing in Mexico. We are grateful to Rosa and Lily for giving us permission to share their story.