Smith, T.J., Coyne, P.J., Parker, G.L., Dodson, P., & Ramakrishnan, V. (2010). Pilot trial of a patient-specific cutaneous electrostimulation device (MC5-A Calmare^®) for chemotherapy-induced peripheral neuropathy. Journal of Pain and Symptom Management, 40, 883-891.

Evaluate the impact on chemotherapy-induced peripheral neuropathy (CIPN) associated with the MC5-A Calmare^® therapy device.

Participants were recruited from the clinical oncology practice by physician referral and advertisements in the waiting rooms. The MC5-A device was applied daily to areas of CIPN determined and assigned to dermatomes. The treatment time was 60 minutes for 10 days. The MC5-A device is intended to induce modulation of pain responses with low frequency simulation to nerves with surface electrodes, raising the “gate” threshold for pain at the spinal cord. Patients were evaluated at baseline and at the end of weeks 1 and 2 of treatment, and then at the end of weeks 4, 8, and 12. Subjects rated their pain immediately before and after treatment.

• N = 16 (were evaluable)
• MEAN AGE = 58.6 years (SD = 10.6 years)
• MALES = 22%, FEMALES = 77%
• KEY DISEASE CHARACTERISTICS: The most frequent diagnoses were breast and colon cancer. The most common chemotherapy drugs that were used were taxanes, platinum, and bortezomib. All subjects had unstable CIPN for at least three months.
• OTHER KEY SAMPLE CHARACTERISTICS: Ten subjects were Caucasian, 6 were African American, 1 was Native American, and 1 reported \"other.\" Ten patients were previously treated for pain with opioids; 4 were treated with gabapentin monotherapy; and others were treated with various drug combinations.

• SITE: Single site
• SETTING TYPE: Outpatient
• LOCATION: Massey Cancer Center, Virginia Commonwealth University, in Richmond, VA

• PHASE OF CARE: Active treatment
• CLINICAL APPLICATIONS: Late effects and survivorship

Prospective study

• Pain numeric rating scale (for pain right now) 
• Quality of life measured by The Uniscale
• Change in use of pain drugs
• Toxicity measured by the Cancer Therapy Evaluation Program, North Central Cancer Treatment Group Symptom Experience Diary

Fifteen of the 16 subjects reported a 20% reduction in their pain score by the end of the study. The pain score was reduced 59% from 5.81 pre-treatment to 2.38 at the end of the 10 days ( P < 0.0001 by paired t-test ). The daily reduction in pain score was 1.02 during the 10 days of treatment. After treatment was discontinued, pain scores returned to pretreatment levels. No changes in opioid doses occurred during the course of the study, with patients on average receiving 110-150 oral morphine equivalents per day. There were no changes in quality of life or symptoms (as evaluated by the Symptom Assessment Diary).

Although 15 of 16 patients experienced a reduction in their pain, drawing any significant conclusions is difficult with such a small sample in a prospective study.

• Small sample of less than 30
• Single site
• Not a randomized, double-blind study
• Short-term follow up period
• There was no discussion of changes in any non-opioid or coanalgesic medications for pain.
• Although the authors reported no changes in daily opioid intake during the study, it is not clear how this was determined.
• Changes in pain were measured only immediately pre- and post-intervention, so it is not clear if any effect occurred during the day other than immediately after the treatment.

MCA-5 therapy required patients to return to the clinic daily for 10 days post-treatment. This expectation may be impractical for many patients. Also, not all facilities would have someone available and skilled to do the procedure. The cost of the therapy could be an issue as well. Further research is needed to evaluate the potential benefits of this type of therapy, and longer term follow-up is needed. Consideration of background medications for pain in analysis of results is important for subgroup analysis. Research in this area using a sham-controlled procedure would be helpful to rule out placebo effect.