Khedr, E.M., Kotb, H.I., Mostafa, M.G., Mohamad, M.F., Amr, S.A., Ahmed, M.A., . . . Kamal, S.M. (2015). Repetitive transcranial magnetic stimulation in neuropathic pain secondary to malignancy: A randomized clinical trial. European Journal of Pain, 19, 519–527. 

To evaluate the effects of transcranial magnetic stimulation on neuropathic pain

Patients with neuropathic pain by standardized assessment were randomized to receive either transcranial magnetic stimulation or sham stimulation. After the identification of optimal scalp location, electrodes were used to apply 20 Hz in pulses every day for 10 consecutive days. Procedures for the actual and sham procedures were the same. Study measurements were done before and after the first, fifth, and tenth sessions, and at 15 days and one month later.

• N = 30
• MEAN AGE = 47.5 years
• MALES: Not provided        
• FEMALES: Not provided
• KEY DISEASE CHARACTERISTICS: Postmastectomy neuropathic pain; soft tissue sarcoma; giant cell glioma

• SITE: Single site  
• SETTING TYPE: Outpatient  
• LOCATION: Egypt

Randomized, sham-controlled trial

• Visual Analog Scale (VAS) for pain

An analysis showed pain reductions in both groups over time, but there were significantly greater pain reductions in the actual stimulation group compared to the sham procedure (p = 0.0001). T tests between groups at each time point showed that there was no real effect of the actual stimulation procedure after the first session. At this point, pain declined and remained stable over time. These effects remained at 15 days but did not remain at one month.

Transcranial stimulation resulted in significant reductions in neuropathic pain. Because the main change occurred after the first session, it was not clear if repeated sessions were beneficial.

• Small sample (< 100)
• Unintended interventions or applicable interventions not described that would influence results
• Other limitations/explanation: No information was provided regarding analgesic use.

The findings of this study suggested that transcranial stimulation can reduce neuropathic pain in patients with cancer. This is a noninvasive technique that may provide an important alternative for pain control. Additional research is needed to determine most effective dosing, timing, and efficacy in comparison to other interventions.