Bold truth: genetic testing can redefine a cancer journey and even alter a family’s future. This rewritten version preserves the core facts and events while expanding explanations and clarifying concepts for readers new to this topic.
Sandra Pérez’s life took a dramatic turn just after her wedding. Barely two weeks later, doctors delivered a terrifying diagnosis: cancer with a grim prognosis if untreated—roughly two months to live. In Mexico City, Sandra had grown up healthy among a close-knit community. She trained as a lab technician, later becoming a sales manager for Illumina in Mexico. An active athlete who loved running, she began experiencing troubling symptoms in fall 2023: increasingly difficult breathing and recurring painful ulcers in the back of her throat. A private blood test produced results that immediately alerted her to a serious problem.
As a trained chemist with a master’s degree in biotechnology, Sandra understood the implications quickly. “When I saw the results, I thought, this is not good,” she recalls. Her red blood cell count was dangerously low. A hematologist prescribed vitamin B12 and folic acid to support blood cell production, but when there was no improvement, she was admitted to the Centro Médico Nacional Siglo XXI hospital in Mexico City. On January 4, 2024, she received the diagnosis: acute myeloid leukemia (AML), a rare form of blood cancer that represents about 1% of new cancer cases. The disease had already crowded 40% of her bone marrow, making immediate chemotherapy essential.
Pursuing answers through genomics
Feeling overwhelmed, Sandra leaned on a professional network she had cultivated through years in health sciences. She decided to pursue biomarker testing as a next step. With expert guidance, she underwent a next-generation sequencing (NGS) panel for AML. The results revealed a GATA2 gene mutation and an ETV6:MECOM fusion—genetic changes associated with poorer prognosis and a higher risk of relapse.
In AML treatment, the typical path begins with four to five cycles of chemotherapy. If relapse occurs—around half of patients relapse—the protocol often includes additional rounds. Sandra’s genetic findings, however, opened the door to a different option: a bone marrow transplant, a strategy usually reserved for patients at high relapse risk.
“I was fortunate enough to be considered for the transplant protocol from the outset because of my genetic testing,” she notes. The search for a compatible donor then began. Family members on her mother’s side underwent human leukocyte antigen (HLA) compatibility testing, but no match emerged. Sandra, who had grown up without her father and lacked connections to paternal relatives, faced a difficult challenge in locating potential donors.
A breakthrough came when Sandra discovered that she had a sister, Valeria, whom she had never known. Through an online search of a university thesis, the family located Valeria and contacted the thesis director, who facilitated an introduction. The emotional hurdle was significant: explaining to a sister she might not have known existed, and who might not know about her, that they could be half-siblings and that a donor match could save her life.
Valeria agreed to undergo an HLA compatibility test and turned out to be a match. She chose to donate.
After completing the initial four chemotherapy rounds, Sandra underwent the bone marrow transplant in October 2024 and has been steadily recovering since.
Access to genetic testing changes lives
If Sandra had not pursued genetic testing, her treatment path could have consisted of four to five chemotherapy cycles followed by two years of low-dose therapy. Relapse, which remained a real possibility given the mutations identified by the NGS panel, would have likely diminished her chances of a successful recovery, even with subsequent chemotherapy. Instead, genetic testing enabled her to receive chemotherapy concurrently with a bone marrow transplant, a combination that substantially altered her prognosis.
Today, less than two years after her AML diagnosis, Sandra is in remission. She continues to manage her transplant care with preventive medications, maintains regular medical checkups, and works with a nutritionist to sustain her health. She has returned to her activities, including home workouts and running, with renewed energy.
Sandra reflects on her unique fortune. Her scientific background and professional network granted access to the NGS panel that reshaped her fate. In many parts of Mexico—and around the world—biomarker testing remains inaccessible or prohibitively expensive through public insurance. “I was able to obtain genetic testing not because it was covered by public health care, but thanks to the network I built,” she explains. Private care often offers access, but affordability remains a critical barrier.
She advocates for broader genomic access, arguing that genomic insights allow clinicians to tailor treatment to an individual’s risk profile rather than relying on one-size-fits-all approaches. “Genomics awareness among doctors and patients is essential, especially in places like Mexico where access is still limited,” she emphasizes.
Efforts by companies and the broader medical community aim to broaden access to genomic testing and educate clinicians and patients about the benefits of NGS. Ongoing advancements and growing awareness are integrating genomic education into standard cancer care.
A beacon in a dark period
Nearly two years after her AML diagnosis, Sandra also discovered a sister she never knew existed. Valeria’s decision to donate not only offered a life-saving chance but also created a powerful, life-affirming connection within the family. The experience proved a beacon of hope during one of the darkest chapters of Sandra’s life.
Today, Sandra credits her recovery to a combination of personal commitment to staying healthy, strong support from family and friends, professional colleagues at Illumina, and the transformative potential of genomic testing. She is back at work and more determined than ever to expand access to NGS across Latin America. By sharing her story, she hopes to empower others to advocate for genomic testing, ask questions, and take an active role in their treatment journeys.
Disclaimer: This account highlights one individual’s experience with biomarker testing and next-generation sequencing. While it illustrates the potential benefits, results from biomarker testing can vary based on a range of factors, and may not be predictive for every case.
