Researchers in rectal cancer have demonstrated in a large clinical trial that patients do just as well without radiation therapy as they do with radiation therapy, a daunting task. accomplished great deeds.
The results were presented Sunday at the American Society of Clinical Oncology annual meeting. paper The paper, published in the New England Journal of Medicine, may give more than 10,000 patients in the United States each year the option to stop cancer treatments that can cause serious side effects. be.
The study is part of a new direction for cancer researchers, said Eric Weiner, Ph.D., president of the oncology organization but not involved in the trial.
“With advances in cancer treatments, researchers are starting to ask questions,” he says. “They are not asking how cancer treatments can be enhanced, but whether there are components of successful treatments that can be eliminated to provide patients with a better quality of life.”
That’s why researchers reviewed the standard of care for rectal cancer, which affects 47,500 people annually in the United States (although the disease class studied affects approximately 25,000 Americans annually). are affected).
For decades it was common to use pelvic radiation. However, radiation can lead women to immediate menopause and damage sexual function in both men and women. It can also damage the intestines and cause problems such as chronic diarrhea. Patients are at risk of pelvic fractures, and radiation can cause more cancer.
However, the study found that radiation therapy did not improve outcomes. After a median follow-up of 5 years, there was no difference in key measures (survival without signs of cancer recurrence and overall survival) between the treated and untreated groups. And after 18 months, he found no difference between the two groups in quality of life.
Kimmy Ng, Ph.D., co-director of the Colorectal Cancer Center at Dana-Farber Cancer Institute and not the author of the study, said that for colon and rectal cancer professionals, the results are life-changing for patients. said it was possible.
“Now, especially with younger patients, do they really need radiation?” she asked. “How can we choose patients who will not have to undergo this highly harmful treatment that can have lifelong consequences such as infertility and sexual dysfunction?”
Dr. John Prastalus, a radiation oncologist at Penn Medicine Abramson Cancer Center, said the results were “certainly interesting,” but he had to wait long-term for patients before concluding the results of the two treatment options. It was the equivalent that I added that I wanted to be tracked.
The trial focused on patients whose tumors had spread to lymph nodes and tissues around the intestine, but not to other organs. This subset of patients, whose cancer is considered locally advanced, makes up about half of her 800,000 new cases of rectal cancer worldwide.
In this study, 1,194 patients were randomly assigned to one of two groups. One group received standard care. It was a long and difficult ordeal that began with radiation therapy, followed by surgery, and then chemotherapy at the doctor’s discretion after the patient had recovered from surgery.
The other group received an experimental treatment of chemotherapy first and then surgery. Another round of chemotherapy may be given at the doctor’s discretion. These patients received radiotherapy only if their initial chemotherapy failed to shrink their tumors, a rate of only 9%.
Not all patients are eligible for clinical trials. The researchers excluded patients whose tumors were deemed too dangerous for chemotherapy and surgery alone.
“We said, ‘No, that’s too dangerous,'” said Dr. Deborah Schrag of Memorial Sloan Kettering Cancer Center, who led the trial. These patients received standard radiotherapy.
Dr. Schrag and Dr. Ethan Bash of the University of North Carolina at Chapel Hill went a step further and asked patients to report their quality of life. “How much pain were you in?” How tired were they? How long have you had diarrhea? Did they suffer from neuropathy? Were their hands and feet tingling and numb? How was their sex life? Have your symptoms subsided? How long did it take for your symptoms to go away?
“When 80% of patients are alive after five years, we want to say they are doing well,” Dr. Schrag said.
The two groups had various symptoms at various times. After two years, however, there was a trend toward improved quality of life in the group receiving chemotherapy. And on one measure, male and female sexual function, the chemotherapy group performed significantly better.
Nausea, vomiting, and fatigue were more common in the early stages of chemotherapy in patients who received chemotherapy without radiotherapy. A year later, Dr. Bash said the radiotherapy group was further suffering from symptoms such as fatigue, sexual dysfunction and neuropathy.
“Patients who are choosing between radiation and chemotherapy can now look at the results of the patients in the trial and decide which symptoms are most important to them,” said Dr. Bash.
This kind of clinical trial is very difficult. This is known as a phased study because it removes the standard of care to see if it is needed. No company will pay for such tests. And even the National Institutes of Health is reluctant to support their research, as rectal cancer researchers have found, and the researchers persuaded enough doctors to enroll patients. They argued that they could never get them to do so, and that even if they did enroll, they were concerned that too few patients would agree to participate. It would endanger their health.
The NIH ultimately agreed to sponsor the study, but the concerns were justified. It took him eight years for researchers to enroll 1,194 of her patients at 200 medical centers.
“It was very difficult,” said Dr. Alan Venook of the University of California, San Francisco, who helped design the study.
Dr. Schrag noted that the study would require “incredibly courageous patients” and physicians who were convinced that the study was ethical.
“You are living with this in good conscience,” said Dr. Schlag.
Radiation has long been used as a method of preventing the recurrence of rectal cancer. In many cases, chemotherapy and surgery controlled the disease, but too often the cancer recurred in the pelvis. Horrifying effects can follow, including tumors that encroach on the bladder, uterus, and vagina.
The addition of radiation addressed the recurrence in the pelvis, but created a series of problems of its own.
As the years went by, some researchers began to wonder if radiation was still necessary. Advances in chemotherapy, surgery, and medical imaging techniques have allowed patients to be diagnosed earlier, before their cancer has progressed too far.
Dr. Schrag and colleagues decided to test the idea of eliminating radiation in a pilot study she called “30 Courageous Patients.” The results were encouraging enough to advocate the need for broader research.
Dr Venook said the study was a triumph in many ways.
“There are schools of rectal cancer,” he says. “People think they know what the right answer is.”
Therefore, for the study to be successful, “the surgeons, oncologists and radiation oncologists all need to agree on this protocol,” he added.
And, of course, so did patients like Awilda Peña, 43, of Boston. At age 38, she was diagnosed with rectal cancer.
“I couldn’t believe it,” she said.
She said she agreed to participate in the trial because she was “motivated by the hope” that she could be cured without radiation.
Her hope was granted. She was randomly assigned to a non-radiation group, and she was reassured by the fact that the researchers would closely monitor her for five years. “That gave me strength,” Peña said. She is now cancer free.
“You’re not just doing this for yourself,” she said. “You’re helping great scientists and researchers. You’re taking risks, but you’re contributing something.”