A trial of Scrambler therapy in the treatment of cancer pain syndromes and chronic chemotherapy-induced peripheral neuropathy.

Neuropathic pain is common among cancer patients and often difficult to treat. This study used Scrambler therapy, a patient-specific electrocutaneous nerve stimulation device, to treat cancer patients with pain. Patients received Scrambler therapy for 10 sessions (one daily) over a two-week period. The primary outcome was changed in pain numerical rating scale (NRS) at one month; secondary outcomes were changes in the Brief Pain Inventory and European Organization for Treatment and Cancer QLC-CIPN-20(EORTC CIPN-20), over time. Thirty-nine patients, mean age 56.5 yr, 16 men and 23 women, were treated over an 18-month period for an average of 9.3 days each. The "now" pain scores reduced from 6.6 before treatment to 4.5 at 14 days, 4.6, 4.8, and 4.6 at 1, 2, and 3 months, respectively (p < 0.001). Clinically important and statistically significant improvements were seen in average, least, and worst pain; BPI interference with life scores, and motor and sensory scales on the EORTC CIPN-20. No adverse effects were observed. In this single arm trial, Scrambler therapy appeared to relieve cancer-associated chronic neuropathic pain both acutely and chronically, and provided sustained improvements in many indicators of quality of life.

Pilot trial of a patient-specific cutaneous electrostimulation device (MC5-A Calmare®) for chemotherapy-induced peripheral neuropathy.

CONTEXT: Chemotherapy-induced peripheral neuropathy (CIPN) is a major dose-limiting and persistent consequence of numerous classes of antineoplastic agents, affecting up to 30%-40% of patients. To date, there is no effective prevention or therapy. An evolving hypothesis for reducing CIPN pain involves direct nerve stimulation to reduce the pain impulse. OBJECTIVES: To evaluate the impact on CIPN associated with the MC5-A Calmare® therapy device. METHODS: The MC5-A Calmare® therapy device is designed to generate a patient-specific cutaneous electrostimulation to reduce the abnormal pain intensity. Sixteen patients from one center received one-hour interventions daily over 10 working days. RESULTS: Of 18 patients, 16 were evaluable. The mean age of the patients was 58.6 years-four men and 14 women-and the duration of CIPN was three months to eight years. The most common drugs were taxanes, platinums, and bortezomib (Velcade, Millenium Pharmaceuticals, Cambridge MA). At the end of the study (Day 10), a 20% reduction in numeric pain scores was achieved in 15 of 16 patients. The pain score fell 59% from 5.81±1.11 before treatment to 2.38±1.82 at the end of 10 days (P<0.0001 by paired t-test). A daily treatment benefit was seen with a strong statistically significant difference between the pre- and post-daily pain scores (P<0.001). Four patients had their CIPN reduced to zero. A repeated-measures analysis using the scores from all 10 days confirmed these results. No toxicity was seen. Some responses have been durable without maintenance. CONCLUSION: Patient-specific cutaneous electrostimulation with the MC5-A Calmare® device appears to dramatically reduce pain in refractory CIPN patients with no toxicity. Further studies are underway to define the benefit, mechanisms of action, and optimal schedule.