Effect of Transcranial Direct Current Brain Stimulation of the Motor Cortex on Chemotherapy-Induced Nausea and Vomiting in Female Patients with Breast Cancer.

Abstract

Chemotherapy-induced nausea and vomiting (CINV) is an adverse outcome associated with chemotherapy and is sometimes difficult to manage. This study aimed to examine the impact of a single session of transcranial direct current brain stimulation (tDCS; 2 mA) over the motor cortex for 20 minutes before chemotherapy in patients receiving a highly emetogenic chemotherapy. Prospective randomized double-blind sham-controlled study. Academic medical center. Sixty patients with breast cancer who were scheduled for chemotherapy treatment were selected and allocated randomly into two equal groups: a stimulation group and a sham group. tDCS was implemented over the primary motor area (M1) (2 mA) for 20 minutes. Patients' nausea was measured by a cumulative index of nausea, a visual analog scale for nausea (VAS-N), episodes of vomiting, and the Edmonton Symptoms Assessment Scale (ESAS) to assess symptoms like pain, malaise, and sense of well-being. Evaluation was done before stimulation and every 24 hours for 72 hours after the end of infusion of chemotherapy. The tDCS group showed a reduction in the cumulative index of nausea (P < 0.001, F = 50), the VAS-N (P < 0.001, F = 52), the ESAS malaise score (P < 0.001, F = 37.6), and the sense of well-being score (P < 0.001, F = 25) vs the sham group. Six patients (20%) in the tDCS group required rescue antiemtic therapy vs 14 patients (46.7%) in the sham group (P < 0.028). A single session of M1 tDCS is suggested as an effective adjuvant therapy to control CINV in female patients suffering from breast cancer and receiving highly emetogenic chemotherapy. Corroboratory studies are needed.