Young and middle-aged patients with colon cancer are nearly 2-8 times more likely to receive postoperative chemotherapy than older patients, yet study results suggest no added survival benefit for these patients (JAMA Surgery 2017; doi:10.1001/jamasurg.2016.5050).

Colorectal cancer is the third leading cause of cancer death in the U.S., with an expected 134,490 new cases and 49,190 deaths in 2016. While incidence and mortality rates among adults 50 years and older have decreased in the U.S. in recent years, the same trend has not been observed for patients 20 to 49 years of age. Treatment options for patients with young-onset colon cancer remain to be defined and their effects on prognosis are unclear.

Kangmin Zhu, MD, PhD, of the John P. Murtha Cancer Center, Walter Reed National Military Medical Center, Bethesda, Md., and colleagues examined whether age differences in receiving chemotherapy matched survival gains among patients diagnosed as having colon cancer in an equal-access health care system. The study was based on data from the U.S. Department of Defense's Central Cancer Registry and Military Heath System medical claims databases. There were 3,143 patients ages 18 years to 75 years with histologically confirmed primary colon cancer diagnosed between 1998 and 2007.

Of the patients, 59 percent were men. Young (18-49 years) and middle-aged (50-64 years) patients were 2-8 times more likely to receive postoperative systemic chemotherapy compared with older patients (65-75 years), regardless of tumor stage at diagnosis. Young and middle-aged adults were 2.5 times more likely to receive multi-agent chemotherapy regimens. While young and middle-aged adults who only underwent surgery had better survival compared with older patients, no significant differences in survival were seen between young/middle-aged and older patients who received surgery plus postoperative systemic chemotherapy.

"Most of the young patients received post-operative systemic chemotherapy, including multi-agent regimens, not currently recommended for most patients with early-stage colon cancer," Zhu said. "Our findings suggest young and middle-aged adults with colon cancer may be over-treated."