Radiation-induced xerostomia (dry mouth) is not just a localized side effect of radiation treatment for head and neck cancer. It can cause a painful condition that affects the entire body, beginning with the patient’s inability to swallow and leading to a cascade of malnutrition and poor health. The current standard of treatment for this syndrome utilizes pilocarpine and similar medications taken orally. Although pilocarpine does improve the xerostomia, it causes unpleasant side effects such as polyuria, hyperhydrosis, dizziness, and diarrhea.
Non-pharmaceutical alternative treatment
The American Society for Radiation Oncology (ASTRO) reported encouraging results from the trial of an alternative treatment to pilocarpine in the International Journal of Radiation Oncology • Biology • Physics (Red Journal). The randomized trial, RTOG 0537, is a phase 3, multicenter trial comparing acupuncture-like transcutaneous electrical nerve stimulation (ALTENS) with pilocarpine.1 The study‘s lead author, Raimond K. W. Wong, MBBS, a radiation oncologist and associate professor in the department of oncology at McMaster University in Hamilton, ON, Canada, reported that ALTENS is equally as effective as the current standard treatment.
The group decided to pursue ALTENS as an alternative treatment for radiation-induced xerostomia after a nonrandomized trial published in 2003 found that ALTENS achieved positive results as a therapeutic modality for the condition.2 Similar to a TENS unit, ALTENS utilizes electrodes that the clinician places on the patient’s skin at pre-assigned acupuncture points. The electrodes stimulate these points with low frequency and high intensity pulses. Results demonstrated that patients who received ALTENS had a positive response, and that the treatment could be undertaken in a multicenter trial.3
In the phase 3 trial, the investigators recruited 148 patients from 13 cancer centers in the United States and Canada from August 2010 to December 2011. In order to be eligible, subjects had to complete radiation therapy (with or without chemotherapy) within 2 years prior to enrolling in the trial. They had to have xerostomia of grade 1 or higher based on the Common Terminology Criteria for Adverse Events 3.0.1 Subjects also had to qualify with a Zubrod health performance status of zero to two, of a scale of zero to four. On the Zubrod score, zero indicates that a patient is “fully active, able to carry on all predisease activities without restriction” while a score of four indicates that the patient is “completely disabled, cannot perform any self-care, and is totally confined to bed or chair.”1 Two of the 148 patients originally recruited were disqualified, leaving 146 patients in the trial. Of these, one group of 73 was randomly assigned to receive ALTENS, and the other 73 received pilocarpine.
Treatment began within 14 days of enrollment. Patients in the ALTENS group received two, 20-minute ALTENS sessions weekly for 12 weeks, for a total of 24 ALTENS sessions. Each patient could take a total of two weeks off; missed treatments were made up during the 23-week treatment period. No patient received more than three ALTENS sessions in a week. In this group 68 patients (93%) completed more than 85% of the treatments.1