Gastric myoelectrical activity post-chemoradiotherapy and esophagectomy: a prospective study using subscapular...

The aims of this study were to prospectively evaluate gastric function in esophageal cancer patients after chemoradiotherapy and following surgery, using cutaneous electrogastrography (EGG). Twenty-three patients with esophageal adenocarcinoma were recruited to the study. A subset of patients (n = 11) underwent neoadjuvant chemoradiotherapy and were also studied at 14 days after treatment. All patients underwent EGG studies prior to and following surgery, at 3 months postoperatively. Ten of these patients were also studied at medians of 6 months and 12 months after surgery. Twenty normal volunteers were used as controls. Post-operative EGG studies were monitored with a modified technique; the electrodes being placed in the subscapular region in the area of the transposed stomach. Following neoadjuvant treatment there was a significant increase in abnormal gastric myoelectrical activity involving changes in tachygastrias and decreased motility as measured by power ratio. Post-operatively there was a significant increase in bradygastria which persisted at 6 months but not at 12 months. There was a corresponding decrease in normogastria which persisted at 6 months and to a lesser extent at 12 months. Dominant frequency remained significantly depressed at 3, 6 and 12 months. Gastric myoelectrical activity is normal in untreated esophageal cancer. Neoadjuvant chemoradiotherapy causes a disruption to normal myoelectrical activity involving reduced motility and tachygastrias. Surgery causes a depression in dominant frequency with a reduced incidence of normogastria at 3 months and 6 months but with a tendency towards normality at 12 months.