After surgery, some cancer patients can safely avoid treatments such as radiation or radiation chemotherapysay two recent studies examining shorter, gentler cancer treatment.
Researchers are looking for ways to predict which cancer patients can avoid unnecessary treatments to reduce costs and side effects.
A new study used a blood test to see which colorectal cancer patients could skip or not receive chemotherapy after surgery. Another study suggests that some low-risk breast cancer patients may not need radiation after surgically removing a mass or lump, an operation known as a lumpectomy.
The research was recently discussed at the American Society of Clinical Oncology (ASCO) Annual Meeting. Funded by the Australian and US governments and non-profit organizations, the colorectal cancer study was recently published in the New England Journal of Medicine.
The results have doctors paying careful attention to “the patients who we think really would.” To use chemotherapy and avoid the side effects for patients for whom it is likely unnecessary,” said Dr. Stacey Cohen of the Fred Hutchinson Cancer Center. Cohen reviewed the colon cancer results and was not involved with the research.
Colon Cancer Study
Many colon cancer patients receive chemotherapy after surgery, although they may be cured. The drugs can have serious side effects such as nausea, anemia and memory problems.
However, it was difficult to decide which patients did not need further treatment. So the scientists investigated whether a blood test could help doctors make a decision.
The study involved 455 patients who had surgery because cancer had spread to the wall of the colon. After the operation, one group received a blood test specifically for the performed tumor genetic information to find remaining pieces of cancer DNA.
Her care was guided by the blood test. If the test showed no signs of remaining cancer, the patients did not receive chemotherapy. Meanwhile, doctors made chemotherapy decisions for the rest of the patients in the usual way, guided by careful examination of the tumor and nearby tissues.
Fewer patients in the blood test group received chemotherapy — 15 percent versus 28 percent. But about 93 percent of both groups were still cancer-free after two years. In other words, the blood test group did equally well with less chemotherapy.
dr Jeanne Tie from the Peter MacCallum Cancer Center in Melbourne, Australia, led the research. Tie described the results in terms of cancer recurrence – the return of a cancer after a period of improvement.
“In patients where the cancer DNA is not present recognized After surgery, the likelihood of cancer coming back is very low, suggesting chemotherapy is unlikely to benefit these patients,” Tie said.
ASCO President Dr. Everett Vokes said that not having chemotherapy “makes a huge difference in a person’s quality of life, if it can do so without putting them at risk of disease recurrence.”
The other study followed 500 older women with a common form of early-stage breast cancer and low levels of a protein called Ki67, a marker of fast-growing cancer.
After the operation, the women took hormone-blocking pills, a common treatment for this type of cancer. But the women didn’t get radiation treatment.
After five years, 10 of the women saw the cancer come back in the same breast and there was one breast cancer death. The study had no comparison group, but the researchers said the results compare well to historical data for similar patients who had radiation.
dr Timothy Whelan of McMaster University in Hamilton, Ontario, led the study.
“We estimate that the benefits of radiation in this population would be very small compared to the side effects,” Whelan said.
Radiation can cause skin problems, fatigue, and less commonly, long-term heart problems and secondary cancers.
dr NYU Langone Health’s Deborah Axelrod was not involved in the research.
Axelrod described the study as a “feel good message” for patients with low-risk tumors. Axelrod added that the data will help doctors understand which of their patients they can’t give radiation “conveniently and with confidence.”
I’m John Russell.
Carla K. Johnson covered this story for the Associated Press. John Russell adapted it for VOA Learning English.
words in this story
chemotherapy – n. medicinal: the use of chemicals to treat or fight a disease (such as cancer)
To use— v. be useful or helpful to (someone or something)
nausea – n. the feeling in your stomach when you think you might throw up
anemia – n. medicinal: a condition in which a person has fewer red blood cells than normal and feels very weak and tired
tumor – n. a mass of tissue in or on the body made up of abnormal cells
hormone – n. a natural substance produced in the body that affects the growth or development of the body
recognize – V to discover or notice the presence of (something hidden or difficult to see, hear, taste, etc.).