Young and middle-aged colon cancer patients are two to eight times more likely to receive adjuvant chemotherapy (given after surgery) than older patients, researchers have found.
But evidence also shows these patients have no survival benefit from the treatment, suggesting that young and middle-aged adults are being over-treated for colon cancer.
The study with those findings, “Chemotherapy Use and Survival Among Young and Middle-Aged Patients With Colon Cancer,” is published by JAMA Surgery.
Colorectal cancer occurs in the colon or rectum. Among cancers affecting both men and women, colorectal cancer is the second-leading cause of cancer deaths in the United States, according to the Centers of Disease Control and Prevention (CDC).
Estimates indicate that in 2017 there will be 95,520 new cases of colorectal cancer and 39,910 deaths. Patients with early-stage colon cancers (that have not spread to distant sites) usually have surgery as the main or first treatment, and then are offered adjuvant chemotherapy regimens.
Whereas incidence and mortality rates of colorectal cancer among adults 50 years and older have declined in the U.S. in past years, the same tendency has not been seen for young and middle-aged patients.
To investigate whether age differences in receiving chemotherapy for colon cancer were associated with survival benefits, Kangmin Zhu, MD, PhD, of the John P. Murtha Cancer Center, and colleagues examined data from colon cancer patients aged 18 to 75 years who underwent surgery and postoperative systemic chemotherapy. The data was retrieved from the U.S. Department of Defense’s Central Cancer Registry and Military Heath System medical claims databases.
Among the 3,143 patients examined, 1,841 were men (58.6%).
Young (18-49 years) and middle-aged (50-64 years) patients were two to eight times more likely to receive chemotherapy after surgery than older patients (65-75 years) across all tumor stages.
Young and middle-aged patients were 2.5 times more likely to receive chemotherapy with multiple agents than older patients.
Importantly, young and middle-aged patients who underwent surgery without chemotherapy had better survival rates than older patients. But the researchers found no significant differences in survival between young/middle-aged and older patients who underwent surgery followed by chemotherapy.
“This cohort study found that although young and middle-aged patients were 2 to 8 times more likely to receive postoperative systemic chemotherapy for colon cancer than older patients, there was no significant survival difference by age group,” the researchers wrote. “The additional use of postoperative systemic chemotherapy among young and middle-aged persons without matched survival improvement suggests possible overuse of chemotherapy among younger than older adults with colon cancer.”
