Patients with cancer of the larynx are likely to retain their voice and avoid surgery if they are treated simultaneously with chemotherapy and radiotherapy, say investigators who have conducted a nationwide study.

The findings are so significant they should become the new standard of care for stage III and IV laryngeal cancer, says one of the study’s lead investigators, Moshe Maor, M.D., professor of radiation oncology at The University of Texas M. D. Anderson Cancer Center.

“There is no question that this is the best treatment option for those patients who can tolerate chemotherapy,” says Maor, who presented results of the eight-year, 517-patient trial during a “Best in Oncology” special session at the annual meeting of the American Society of Clinical Oncology.

The cancer, which is diagnosed in about 8,000 patients a year, usually as a result of smoking, is traditionally treated with “induction” chemotherapy followed by radiotherapy.

But this study found that this standard therapy, as well as the third tested treatment of radiotherapy alone, resulted in a significantly greater rate of surgery and removal of the voice box because of cancer recurrence.

Specifically, the number of surgeries two years after treatment in patients who were treated with chemotherapy and radiotherapy together was 21, compared to 43 in patients who were treated with standard therapy, and 49 in patients who had radiotherapy alone.

“We believe that when delivered together, chemotherapy sensitizes the tumor to the killing effects of radiation,” says Maor.

Because results from the two inferior treatments were the same, Maor says, the study raises the question of whether chemotherapy, when used by itself before radiotherapy, offers any benefit at all.

“Our theory is that tumors that respond to chemotherapy will respond to radiation anyway,” Maor says. “Thus chemotherapy does not have an additional benefit unless used at the same time as radiotherapy.”