CDX2-Negative Colon Cancer May Need More Tx Post Surgery
Patients with CDX2-negative tumors more likely to benefit from chemo in addition to surgery
THURSDAY, Jan. 21, 2016 (HealthDay News) -- Colon tumors that don't produce the protein CDX2 are more likely to recur following surgical removal in patients with stage II colon cancer, according to study findings published in the Jan. 21 issue of the New England Journal of Medicine.
Michael Clarke, M.D., professor of cancer biology with the Stanford University School of Medicine in Palo Alto, Calif., and colleagues analyzed medical data for 1,897 patients with stage II or stage III colon cancer. The researchers found that 4.1 percent of the patients had tumors that didn't produce CDX2.
In an initial study of 466 patients with any stage of colon cancer, 41 percent of those with CDX2-negative tumors lived disease-free for five years after treatment, compared to 74 percent of those with CDX2 in their cancer cells. Further, patients whose tumor cells didn't express CDX2 were more likely to benefit from chemotherapy in addition to surgery than were patients with CDX2-positive tumors. Ninety-one percent of patients with CDX2-negative cancers treated with surgery plus chemotherapy lived disease-free for five years, versus 56 percent of those who did not receive chemotherapy.
Because this study did not involve a test on new patients, doctors can't be certain that this association is valid, Clarke told HealthDay. "The data are extremely strong, but you need a prospective analysis to be 100 percent sure," he said. "It should be validated in a prospective trial."