Acute, severe toxicity was infrequent. This study confirms for the first time that the benefit achieved with chemotherapy when combined with irradiation is superior to that produced by radiation therapy alone, which many clinicians regard as a standard adjuvant therapy for rectal cancer. That study demonstrated the superiority of chemo-radiation therapy when compared to surgery alone. A reduction in local recurrence was also noted when compared to radiation therapy alone. The new and confirmatory evidence of effective surgical adjuvant therapy for rectal cancer has stimulated a search for safer and still more effective approaches.
Important questions remain.
To date, there are not sufficient data to compare survival rates. But based on increased toxicity and lack of evidence for improved effectiveness, the NCI agrees with the study's investigators that methyl-CCNU, delivered in this manner, is probably not a necessary component of multimodality adjuvant therapy for rectal carcinoma. Both of these combinations are currently being evaluated in protocols sponsored by the National Cancer Institute and are available to eligible, rectal cancer patients throughout North America. In these trials, all patients receive active, postoperative, systemic therapy. Continued accrual of patients to these trials is essential to define further advances in care.