Predicting who benefits from chemotherapy

BARCELONA, Spain, Sept. 26 (UPI) -- Dutch researchers have developed a method to accurately predict which patients with colon cancer would benefit from chemotherapy.

Currently, patients with stage II colon cancer have an overall five-year survival of about 80 percent, however, 75 percent of patients are cured by surgery alone and less than 25 percent of patients would benefit from additional chemotherapy.

Study leader Rob Tollenaar of Leiden University Medical Center and Dr. Laura Van ‘t Veer at The Netherlands Cancer Institute said that they analyzed for the first time the different expressions of genes in the entire genome of tumor tissues from 121 patients with stage II colon cancer who had not received chemotherapy.

"Our analysis showed a cluster of 75 percent of the patients, of whom approximately 90 percent were likely to survive for at least five years with no distant metastases," Tollenaar said in a statement.

"In the second cluster of the remaining 25 percent of the patients, only about 65 percent of them had five-year survival without distant metastases, and this is the group who would be likely to benefit from adjuvant chemotherapy."

Tollenaar presented the findings at the European Cancer Conference in Barcelona, Spain.