Study: Genetic Markers May Help Predict Survival After Colon Surgery

Genetic changes that take place in colon tumors may help doctors predict which patients may benefit most from chemotherapy after having colon surgery, according to researchers at the University of Texas M.D. Anderson Cancer Center in Houston.

Researchers analyzed tumors from 460 patients suffering from stage III and high-risk stage II colon cancer who were treated with various combinations of adjuvant fluorouracil, leucovorin, and levamisole, according to the study published in the New England Journal of Medicine.

Patients who had lost a portion of chromosome 18 were less likely to survive 5 years after surgery compared to other patients, said the researchers. Patients with two other markers (microsatellite instability and a particular gene mutation) were more likely to survive. Microsatellite instability occurs when a defective DNA repair mechanism induces abnormalities in a tumor cell's genetic code.

"Markers that reliably predict survival are needed. Our study is a first step toward the goal of individualized cancer treatment based on the molecular characteristics of the tumor," said the researchers.

Further research is planned to see if these molecular markers are relevant to new chemotherapy medications.

Other sources: New England Journal of Medicine, Reuters