Prognostic significance of beta‐adrenergic receptor expression in oesophageal adenocarcinoma

Abstract Expression of the β‐adrenergic receptors' family has been associated with survival outcomes in multiple different cancer types, showing their potential to act as prognostic factors. No previous work has evaluated these receptors in relation to survival in oesophageal adenocarcinoma. We sought to analyse the expression of β 1 and β 2 adrenergic receptors in oesophageal adenocarcinoma and their association with survival outcomes. The expression of β 1 and β 2 adrenergic receptors was evaluated in a cohort of oesophageal adenocarcinoma patients treated with neo‐adjuvant chemotherapy prior to surgical resection at the Northern Ireland Cancer Centre between 2004 and 2012. Immunohistochemical staining for was assessed using a Tissue Microarray with triplicate tumour cores. Cox proportional hazards regression was used to investigate the association of β 1 and β 2 adrenergic receptor expression with survival outcomes, including adjustment for clinical factors. In total, 115 and 122 patients were assessed for β 1 and β 2 adrenergic receptor expression, respectively. In adjusted analysis, high β 2 adrenergic receptor expression was associated with improved recurrence‐free [hazard ratio [HR] 0.57, 95% CI 0.33–0.97] and overall survival (HR 0.53, 95% CI 0.30–0.94) with restriction to gastro‐oesophageal junction tumours showing a stronger association with improved overall survival (HR 0.27, 95% CI 0.13–0.59). No significant association was observed for β 1 adrenergic receptor expression and any survival outcome. In summary, we found that higher expression of the β 2 adrenergic receptor was associated with a significant improvement in survival in oesophageal adenocarcinoma patients, and gastro‐oesophageal junction tumours in particular, treated with neoadjuvant chemotherapy followed by surgical resection.