“Basically we found that if you stop therapy early you get no benefit,” said Dr. Alfred Neugut, study author from Columbia University Medical Center.

   In a study, Neugut and his colleagues identified over 1,500 stage III colon cancer        patients over the age of 64, who began chemotherapy as part of their cancer treatment. All of the patients were prescribed fluorouracil-based adjuvant chemotherapy, standard treatment used to kill any remaining cancer cells after cancer-removing surgery. The treatment may be prescribed in various ways but generally lasts at least six months.

Of these patients, 69 percent continued with treatment for five to seven months, but over 30 percent stopped before four months. While it may seem like four months of chemotherapy would be better than none at all, that’s not the case. Those who stopped treatment early lived almost half as long as those who finished. “If you don’t get all of the treatment, you don’t get all of the benefit,” said Neugut.

It is not clear why patients do not follow through with chemotherapy, but the researchers discovered that patients who were older, unmarried and had health problems in addition to colon cancer were the most likely to stop treatment early. In an earlier study, Neugut found that most women who discontinue adjuvant chemotherapy for breast cancer were most likely to stop because of the adverse side effects.

For colon cancer, however, Neugut suspects that a variety of factors may play into a person’s decision to stop treatment, including side effects of the drug, a patient’s overall health and lack of support at home.