Genetics and Cancer Risk: Real-World Benefits of Genetic Testing

According to the National Cancer Institute, there are many ways to reduce your lifetime cancer risk. You can make mindful food choices, refrain from alcohol, maintain a healthy weight, avoid smoking and stay away from known carcinogens. However, no matter how healthy your lifestyle choices may be, there is no way to change your DNA to reduce your genetic risk of developing cancer. So, what steps can you take if your genetics put you at increased lifetime risk for cancer? 

“In the past, cancer care focused on diagnosis and treatment,” says Melissa Frey, M.D. M.S., associate professor in the Division of Gynecologic Oncology and director of the Genetics and Personalized Cancer Prevention Program at Weill Cornell Medicine. “Today, there is a growing interest in cancer prevention, and cancer genetics is a critical component of making preventative medicine a reality.” 

A Growing Field Meets a Known Need 

Prior to 2000, genetic testing was rarely used. Patients were unaware of genetic testing as an available precision medicine tool, so they didn’t ask healthcare providers about it. Medical practitioners were unsure of its potential and diagnostic power, so they didn’t recommend it. Furthermore, genetic testing was unaffordable for most. Today, that has all changed as modern, cost-effective genetic testing and screening tools provide new and exciting avenues to eradicate cancers in their earliest stages or prevent them entirely — saving countless lives in the process.  

In the past 20 years, genetic testing has become better understood, accepted and implemented as a tool for gaining a more complete picture of patients’ specific risk profiles. As a result, a growing number of cancers are now known to have a strong genetic component and be linked to your DNA. These include the following cancers: 

As the genetic aspects of cancer continue to be elucidated, genetic testing’s role in cancer care continues to expand. This growth represents an important step forward for the treatment of people who are predisposed to cancer, as genetic testing and identification of genetic mutations provide the opportunity for referral of these individuals to cancer screening and risk-reduction strategies that can reduce cancer incidence and mortality. 

“We now know that between 1% and 5% of the general population have a genetic predisposition to certain cancers,” says Ravi Sharaf, M.D., M.S., director of Genetics and Personalized Cancer Prevention, associate professor of Medicine (Gastroenterology) and associate professor of Population Health Sciences (Epidemiology) at Weill Cornell Medicine. “Testing for such genetic predisposition is a big step toward personalized medicine. It allows us to tailor medicine and preventive steps to your specific risk.” 

Purposes of Genetic Testing for Cancer Patients 

Both personal and family history of cancer are key factors in determining whether you are a candidate for genetic testing. The purpose and promise behind the growing field of cancer genetics is that we can use the information in our genes to prevent cancer before it develops or detect cancer at its early stages when treatment is most effective. 

Often, genetic testing takes place after a cancer diagnosis has been made. This information leads to the potential for specific action, such as: 

  • Changes in treatment. Your surgeon may elect to take a different approach, or you may receive customized treatments specially tailored to work well with your genetic makeup. 
  • More comprehensive screening. A genetic mutation increases your risk for developing multiple cancers. Following a cancer screening regimen can help detect cancers early, giving you more treatment options. With a comprehensive understanding of patients’ genetic predispositions, preventive care/screening modalities as well as treatment options no longer need to follow a one-size-fits-all approach and can instead target everyone’s unique risk profile. 

If you are found to carry a mutation that increases your lifetime risk for cancer, a multidisciplinary team through Weill Cornell Medicine’s Genetics and Personalized Cancer Prevention (GPCP) program guides you through your care. Team members may include genetic counselors, nurse practitioners, physicians, social workers, and others. They work together to help you understand your genetic risk, prevent disease and make informed decisions regarding cancer prevention and screening options available to you.  

Reaching Beyond Current Patients 

You do not need a current cancer diagnosis to benefit from genetic testing. It’s also useful if you have a family or personal history of cancer. All people, regardless of racial/ethnic background or family history, should undergo genetic risk assessment. 

Based on your genetic testing results, you will work with the GPCP to determine the best path forward in terms of personalized cancer risk-reduction strategies. You may choose to do one or more of the following: 

  • Make lifestyle changes to reduce your risk for cancer. 
  • Seek earlier or more frequent cancer screening. 
  • Undergo preventive treatments, including surgery or chemoprevention (e.g., Aspirin to reduce your risk of colorectal cancer, or Tamoxifen to reduce your risk of breast cancer). 

Dr. Frey has seen the power of genetic testing to make a difference and save lives in her work in the field of gynecologic oncology. One patient, after learning that she carried a BRCA2 mutation, decided to have surgical removal of her breasts and ovaries/fallopian tubes to reduce her risk of cancer. 

“When our pathologists reviewed the fallopian tubes after surgery, they found a pre-cancerous area,” Dr. Frey says. “While we continue to follow her closely, she’s grateful for the surgery and remains cancer-free five years later.”  

Before the Testing 

An initial consultation is required before genetic testing can be completed. During this first visit, your provider will discuss your personal and family health history, lifestyle, environmental exposures and more. This information will help determine if you would benefit from genetic testing. 

Adequate pre-test education and counseling can help individuals better understand the potential outcomes and make informed decisions. These include the following: 

  • Types of Results in Cancer Genetics 
  • Negative/Normal Result 
  • Positive/Abnormal Result 
  • Variant of Uncertain Significance (VUS) 
  • Genetic Discrimination 
  • The Genetic Information Nondiscrimination Act of 2008 (GINA) is a federal law that protects against discrimination by health insurers and from discrimination at work. This law does not include protections for life, disability and long-term care insurance.  
  • New York State Article 79-l of the Civil Rights Laws (CVR § 79-l) address the confidentiality of genetic test results and prohibit the misuse of genetic information by health insurers. You can locate the full content of these laws at Civil Rights Laws (CVR § 79-l) 
  • Health Insurance Portability and Accountability Act (HIPAA) prevents employers from denying health insurance based on genetic information.  
  • Executive Order 13145 prohibits agencies of the federal government from obtaining genetic information about their employees or job applicants and from using genetic information in hiring and promoting decisions. 
  • Privacy and Confidentiality 
  • Information about the privacy and confidentiality of genetic information, including who will have access to the results and how the information will be stored and protected. 
  • Psychosocial 
  • Considers the potential emotional, social and ethical aspects associated with the results of genetic testing. Examples include family dynamics, communicating and disclosing results to at-risk family members and coping strategies.  

Once informed consent is administered, you can undergo genetic testing. All that is required of you is a simple blood draw. This sample then gets sent to a laboratory and tested. For people who prefer telemedicine, the sample can be sent as a saliva collection directly from your home. Soon after, your provider contacts you with your results. 

Testing Wherever You Are 

Because genetic testing is such a powerful tool in cancer care, Weill Cornell Medicine experts want to expand access to genetic testing services for all those in need. They encourage primary care providers and specialists to screen every patient to identify those who would benefit from testing. All candidates who meet the criteria should then receive education about genetic testing and support should they decide to undergo genetic testing.  

To make this process easier, the Weill Cornell Medicine genetic team has created a series of videos, in several languages, for providers to offer patients. If you are interested in genetic testing, you can watch these videos at your provider’s office or on your smartphone.  

“Our goal is not to be a burden,” Dr. Sharaf says. “We want to meet patients where they are and make the process as easy as possible.” 

Looking to the Future, Living in the Present  

Cancer prevention has been at the forefront of medical research and development for decades and the connection between genetics and cancer is becoming clearer each day. Genetic testing and screening tools are providing new and exciting avenues to eradicate cancers in their earliest stages or prevent them entirely. 

One day in the future, genetics may play a role in routine medical care, but that day hasn’t arrived just yet.  

“Until genetic risk assessment becomes standard of care, the responsibility falls on every individual to advocate for themselves,” Dr. Frey says. “Find a clinician with expertise in the field of cancer genetics and ask if testing is right for you.” 

Do your genes increase your cancer risk? Find a doctor at Weill Cornell Medicine who can assess your risk level.