CHICAGO, July 15 (UPI) -- Although patients given chemotherapy after surgery for colon cancer are known to benefit from the additional treatment, doctors have lacked proof the therapy has an effect on patients with stage 2, high-risk cancer -- until now.
Researchers at the University of Illinois Chicago found in a large study of stage 2 colon cancer patients that adjuvant chemotherapy improves survival, regardless of a patient's age, risk for the return of cancer or the type of chemotherapy used for treatment.
Colon cancer is the third most commonly diagnosed cancer and is the second leading cause of cancer death in the United States.
Typically, only high-risk patients discuss post-surgical chemotherapy with their doctors, but data in the study showing most patients benefit from the treatment suggests all stage 2 colon cancer patients should have the conversation.
"Certainly, we expected to see differences in the data," Dr. Ajay Maker, an associate professor of surgery at the University of Illinois Chicago, said in a press release. "But to find a clinically relevant association with overall survival across all subgroups of patients, including low-risk patients, is noteworthy and very relevant to future research on the potential use of adjuvant chemotherapy as a treatment for stage 2 colon cancer."
For the study, published in the journal Cancer, researchers analyzed data on 153,110 patients with stage 2 colon cancer collected for the National Cancer Database between 1998 and 2006.
The data showed nearly all patients saw benefits from additional treatment after surgery, regardless of age, sex, race, treatment facility, insurance, timing of diagnosis or how high the relapse risk for their cancer was considered to be.
While the researchers caution against overvaluing retrospective associations, they say the results show more studies are needed to find the groups of patients who would benefit most from adjuvant chemotherapy.
"The results of this study are exciting, and certain aspects not entirely expected," Maker said. "For many years, studies have included, but not focused on, stage 2 colon cancer patients. This study, which looks at the largest group of stage 2 colon cancer patients to date, set out to better understand the role of adjuvant chemotherapy in treating patients that are fighting this specific type and stage of cancer."