Survival rates have drastically improved in recent decades, and physician-researchers are working toward more personalized treatments.
Cancer treatment and survivorship has come a long way. According to the American Cancer Society, there are more than 14 million cancer survivors in the United States, and more than 2 in 3 people diagnosed with cancer will live at least five years. That number was just 1 in 2 during the 1970s, when cancer treatment as we know it today started to take shape.
This year, the American Cancer Society announced that the cancer death rate dropped 27 percent in 25 years.
Historically, there have been three methods of treating cancer: surgery, radiation and chemotherapy. Along with advancements in these mainstays, options such as immunotherapy have developed. These therapies and evolving research are making the disease in all its forms less lethal and more treatable.
To see how far we’ve come, let’s take a look at how it all started.
The Earliest Cancer Treatments
The term “cancer” originated with the Greek physician Hippocrates, who lived around 400 BC. Early physicians considered the disease a death sentence, even when surgery became an option (the second century Greek doctor Galen did write that surgery could cure breast cancer if the tumor was completely removed). There was no anesthesia at that time and complications were numerous, making surgery dangerous.
Many centuries later, the invention of anesthesia in the mid-1800s allowed rapid advances in surgical treatment of tumors. In the 1890s at Johns Hopkins University, professor William Stewart Halsted developed the radical mastectomy —surgically removing the breast, chest muscle and nearby lymph nodes—as a treatment for breast cancer. That extensive treatment became the basis of cancer care for the next century. But because it was still unknown exactly how cancer spread to different parts of the body, it was not a cure-all treatment for every patient.
During this time, an English surgeon by the name of Stephen Paget was theorizing why cancer seemed to grow in certain parts of the body, and how it spread from place to place. He thought the bloodstream was the answer, and he was right. His theories led to a different approach to treating cancer.
Less Invasive Options for Cancer Treatment Emerge
In 1896, German physics professor Wilhelm Conrad Roentgen presented his theory of the X-ray, a form of electromagnetic radiation. The system was quickly used as a diagnostic tool, and three years later radiation therapy was used to treat cancer. In France, researchers discovered that daily doses of radiation over several weeks would better the chances of curing a patient.
“Radiation has been used for more than 100 years to successfully treat cancer patients,” says Andrew Wang, MD, associate professor of radiation oncology in the UNC School of Medicine. “However, physicians quickly discovered it could also cause cancer. Many of the pioneers of radiation, like Marie Curie, developed cancer or other diseases from the work they did.”
With that knowledge, radiation therapy continued to transform into a more targeted treatment. Surgery coupled with radiation became the treatment protocol for many cancers.
“With radiation we are able to treat a much larger area to make sure we get all the cancer, whereas in surgery you can only remove so much without taking out vital tissue and organs from the body,” Dr. Wang says. “But when it comes to cancer that’s metastasized, chemotherapy is a better option, because you cannot use radiation on someone from head to toe.”
Chemotherapy is the use of chemical substances such as drugs to kill cancer. Some of the first chemotherapy chemicals were discovered accidentally during World War II through U.S. government testing of chemical warfare agents. Not long after that, Sidney Farber, MD, discovered another chemical for chemotherapy while working in Boston.
“Dr. Farber was trying to treat childhood leukemia,” says Benjamin Vincent, MD, assistant professor of medicine in the UNC School of Medicine. “He gave patients doses of folate, thinking it would stop cancer growth, but it actually made it worse. He then worked with a biochemist to test an anti-folate, which was able to induce temporary remission in some patients.”
This anti-folate was a predecessor to methotrexate, which became the first treatment to cure metastatic cancer in 1956.
In the late 19th and early 20th centuries, the basis of hormone therapy treatment was discovered by separate physicians in Scotland and Chicago. The revelation of the roles of estrogen in breast cancer and testosterone in prostate cancer led to hormone inhibitor medications that are still used to treat each of these cancers today.
The Modern-Day Approach to Cancer Treatment
Scientists have learned more about cancer in recent decades than they did in all previous centuries.
“In the 1970s, physicians started giving patients chemo and/or radiation before surgery to shrink tumors for anal cancer,” Dr. Wang says. “They found that the combination of treatments for that type of cancer worked dramatically, to the point where surgery wasn’t needed. From then on the chemo-radiation paradigm was applied to other cancers, and is now the standard of care for many early cancers throughout the body.”
Multiple types of radiation have been introduced into treatment settings, including electrons and protons, which are just as effective as previous forms of radiation against cancer cells but less damaging to healthy cells.
The 1970s also brought the emergence of imaging technologies like ultrasound, CT (computerized tomography), MRI (magnetic resonance imaging) and PET (positron emission tomography) scans, which gave physicians a better look into the body of a patient.
“Imaging has pretty much replaced exploratory surgery,” says Jen Jen Yeh, MD, professor of surgery and pharmacology in the UNC School of Medicine.
Previously, exploratory surgeries were used to do just that—explore the inside of a patient’s body to learn more about what cancer they are suffering from and how or if it has spread. Now imaging can be used in all steps of a patient’s cancer fight: diagnosis, treatment and remission. It especially helps with determining which combination of treatments would be most successful for a patient. Surgery, chemotherapy and radiation can be used in numerous combinations or sequences to cure many types of cancers. For early cancers, many times surgery is all that’s needed.
Targeted Therapies and Immunotherapy for Cancer
Even with all these advancements, there is still no “cure-all” cancer treatment, mainly for one key reason.
“We have to remember that cancer is not one disease,” Dr. Yeh says. “Breast cancer in one person is not the same as breast cancer in another person. Cancer cells have their own genetic makeup.”
Dr. Yeh’s research lab is digging into the differences among tumors. So far, the team has identified two additional tumor subtypes within pancreatic cancer that have unique genetic expressions, one of which doesn’t respond to current routine therapy.
“To give patients the best treatment options from the beginning, we need to learn as much as we can about their tumors,” she says.
This approach to treatment—targeted therapy—targets specific genetic alterations in tumors and is growing in practice, Dr. Yeh says. Other treatments target cancer cells after they have spread or while they are in the process of spreading, but targeted therapies use drugs to prevent the cancer cells from spreading in the first place. For example, growth signal inhibitors are a targeted therapy that blocks signals inside the cells that tell them to grow, stopping the cancerous cell before it can divide and spread. These therapies are now very common in treatment of breast cancer and advanced stage colon cancer, along with recurring or metastasized cancers.
Immunotherapies that train the immune system to recognize and reject cancer are increasingly being used to treat cancers that haven’t previously been curable.
“I see immunotherapy as the future of cancer treatment,” says Dr. Vincent, who oversees clinical trials of CAR T-cell immunotherapies. “Many immunotherapy treatments are much more tolerable than chemo or radiation therapies. The real hope is that it will reduce or even replace the use of more toxic therapies.”
Dr. Yeh says there’s more hope for people with advanced cancer due to all the treatment methods available and in development. And if a cancer isn’t curable, the medical community is getting better at extending life and making quality of life better for patients, she adds.
For those who don’t see the improvements being made, Dr. Vincent says, “the progress of science sometimes looks slow day to day. But when you look over a lifetime you can see how dramatically we have improved treatments. I’m hopeful in another 50 years it will be better than we can dream now.”
Are you concerned about your cancer risk? Talk to your doctor or find one near you.