(HealthDay News) — There are no statistically significant differences in the rates of local recurrence (LR), distant recurrence, relapse-free survival, overall survival, or late toxicity in rectal adenocarcinoma patients treated with short-course (SC) radiotherapy or long-course (LC) chemoradiation, according to research published online Sept. 24 in the Journal of Clinical Oncology.
Samuel Y. Ngan, M.D., of the Peter MacCallum Cancer Centre in Melbourne, Australia, and colleagues conducted a study involving 326 patients with T3N0-2M0 rectal adenocarcinoma to compare the LR rate between SC and LC neoadjuvant radiotherapy for rectal cancer. SC consisted of pelvic radiotherapy, early surgery, and six courses of adjuvant chemotherapy, while LC included radiotherapy with continuous infusional fluorouracil, followed by surgery and four chemotherapy courses.
The researchers found the three-year LR rates to be 7.5 and 4.4 percent for SC and LC, respectively. Five-year distant recurrence rates were 27 and 30 percent for SC and LC, respectively. Overall five-year survival rates were 74 versus 70 percent. Finally, late toxicity rates were not substantially different for SC- and LC-treated patients. None of these differences were statistically significant.
“The trial data indicate that LC may be more effective than SC in reducing the risk of LR, especially for distal tumors,” the authors write. “However, we have not been able to definitively determine that such a difference does exist, and further study would be required to help clarify this issue.”
One author disclosed financial ties to pharmaceutical companies.