Clinicians in the United Kingdom are not consistent regarding the duration of chemotherapy for patients with advanced colorectal cancer.
In this study, researchers sought to compare the effectiveness of continuous and intermittent chemotherapy in colorectal cancer patients.
Patients who responded, or had stable disease, after receiving 12 weeks of the regimens described by de Gramont and Lokich, or raltitrexed chemotherapy, were included in the study. They were randomized to receive either intermittent chemotherapy, or continuous chemotherapy until progression.
The intermittent treatment consisted of a break in chemotherapy, followed by re-starting on the same drug on progression.
The research team enrolled 354 patients from 42 centers in the study. Of these, 178 received intermittent treatment and 176 continuous.
|Patients on intermittent chemotherapy had significantly fewer toxic effects.|
At randomization, 41% of participants had part or complete response, while 59% were stable.
Only 37% of patients allocated to the intermittent treatment restarted as planned, after a median of 130 days.
The team found that the median time on treatment after restarting was 84 days.
The patients in the continuous group remained on treatment for a median of a further 92 days.
The team determined that similar proportions of patients in both groups received second-line therapy.
However, patients on intermittent chemotherapy had significantly fewer toxic effects and serious adverse events than those in the continuous group.
The research team found little clear evidence of a difference in overall survival.
Dr Maughan's team concluded, "Our findings provided no clear evidence of a benefit in continuing therapy indefinitely until disease progression".
"They showed that it is safe to stop chemotherapy after 12 weeks and re-start the same treatment on progression in patients with chemosensitive advanced colorectal cancer."