Personalized Cancer Treatment
The Personalized Approach to Cancer Treatment
Cancer was diagnosed in more than 1.6 million people in the United States in 2012. And despite many common features among this large number of people, the cancer experience varies from person to person. Advances in screening and earlier detection have allowed more people to live longer overall and to live longer with cancer remaining stable (not progressing). New treatments have also led to better survival rates, especially for people with more advanced disease. Still, not every treatment is effective for every person. Why?
Researchers have been studying thousands of samples from various types of tumors, and they have discovered that tumors differ in very important ways, even when they’re from the same body site, such as the breast, colon or lung. Researchers have also found that some cancers are associated with substances that are released into the bloodstream – either directly from cancer cells or from other cells from the tissues surrounding the tumor that are responding to the cancer growth. Known as biomarkers, these substances (usually proteins) help doctors know more about a tumor. This content is designed to help you better understand biomarkers and their role in personalized cancer treatment.
Overview of biomarkers
Biomarkers can help your doctor better predict the chance your cancer will return (known as recurrence) or spread (known as metastasis) as well as your prognosis (the likely course of your disease). Biomarkers can also make it possible for your doctor to monitor how well you respond to treatment. These benefits are an important part of creating a personalized plan.
In addition, advanced testing methods are now available for analyzing tumor samples and other tissue to look for abnormal features in genes. These abnormalities can cause some cancers to develop or spread. With these testing methods, researchers can look for genetic mutations (or genetic alterations) in some tumors that can help guide treatment decisions. Biomarker testing has improved cancer care by helping doctors match the right person with the right treatment plan. Learn about biomarkers here.
In addition to tumor tissue, abnormal features in other body cells can lead to a greater hereditary risk for some cancers. Genetic counseling and testing provide the chance for people to better understand their risk and work with their doctors to create a personalized approach to preventing or decreasing the risk of cancer. Learn more about genetic mutations, genetic counseling and genetic testing here.
Biomarkers and clinical trials
Clinical trials are important because they evaluate the safety and effectiveness of new testing methods and new drugs for people with cancer. In some trials, researchers are studying the role of biomarkers in the development of cancer and learning more about how genetic alterations affect how cells develop many types of cancers. This knowledge helps researchers develop new drugs that block cancer growth or send signals that damage cancer cells. These new drugs are called targeted therapy drugs because of the way they target a specific cell function. Learn more about targeted therapy here.
Targeted therapy drugs are evaluated in clinical trials, and drug evaluation is becoming more efficient because many trials are done only with those people (or tumor samples) with specific genetic alterations in the tumor. Traditional chemotherapy drugs also continue to be studied in clinical trials, and researchers look for reasons why cancer responds to these drugs in some people but not others.
This content describes how biomarkers and targeted therapy work together in the fight against several major types of cancer—primarily breast, colorectal and non-small cell lung cancer, as well as melanoma and some leukemias, lymphomas and sarcomas. Because it is not possible to address every aspect of these topics, you will be directed to websites where you can find more details to help you better understand the personalized treatment of cancer.
People with newly diagnosed cancer are often fearful because they remember what a family member or friend went through with cancer. But research advances have changed the cancer experience in many important ways. What doctors know today about cancer is worlds away from what they knew in your parents’ and grandparents’ day (see boxes). Learn all you can about your cancer and its treatment so that you can work with your doctor to select a treatment that is right for you.
Then and now in personalized treatment
1. THEN...All tumors were thought to be the same.
NOW...Tumors are known to be very different from each other.
Researchers once thought that all tumors from a particular site (for example, the breast) were the same. Now, researchers have identified the molecular features of a tumor and found that the molecular, or genetic, profile can vary greatly, even among tumors from the same site. For example, instead of breast cancer being one type of cancer, it is now five different subtypes, depending on its genetic profile. The discovery of these subtypes helps explain why a treatment works for one person but not another.
2. THEN...The approach to treatment was “one size fits all.”
NOW...More options are available for controlling cancer.
Chemotherapy drugs, surgery and radiation therapy were once the only treatment options for cancer. Although these are still used, doctors now know that some cancers respond better to some drugs than others and that less is usually better with surgery and radiation. For example, the removal of just the breast tumor with some nearby tissue (known as a lumpectomy) has been found to be as effective as removal of the entire breast for many women. Plus, a new treatment approach – targeted therapy – allows for more focused treatment in some cancers. Substantial advances in medications to relieve the side effects of treatment also make it possible to keep people more comfortable during treatment.
3. THEN...Doctors called all the shots when making treatment decisions.
NOW...People with cancer are encouraged to be part of the decision-making process.
Because treatment choices were once limited, doctors alone decided which was best. With more options now available, doctors today ask their patients to be active participants in making decisions. If you have cancer, learn all you can about your particular tumor so that you can work with your doctors to choose a treatment plan that is best for you based on your preferences as well as your doctor’s knowledge of optimal treatment.
4. THEN...Doctors and their patients merely hoped that treatment would keep cancer from recurring.
NOW...Tests are available to help doctors predict if cancer will recur or respond to treatment.
Doctors once chose treatment based on what worked well for other patients with the same type of cancer. However, doctors often had no way to know how likely it was that cancer would recur (come back) after treatment. The discovery of biomarkers and the ways to test for them have helped doctors predict the likelihood of recurrence and response to treatment. Biomarker testing is helping people with cancer avoid treatment that is not likely to be effective. This testing also helps people with a high risk of recurrence receive more aggressive treatment to increase the chance of a good outcome.
5. THEN...Cancer was a death sentence.
NOW...Many cancers are treated as chronic diseases.
A diagnosis of cancer once created a fear of imminent death, with few options for cure. Earlier diagnosis and improvements in treatments for several different types of cancer have led to many people living longer, either with no cancer or with cancer that is controlled (not progressing). The American Cancer Society estimates that since the early 1990s, nearly three-quarters of a million cancer-related deaths have been prevented. In addition, the number of cancer survivors has grown steadily over the past 40 years, from 3 million in 1971 to about 10 million in 2001 to nearly 12 million in 2007.