Mrs Medoway is a 55 year old teacher and attends the GP surgery with a 4 month history of reflux which has been resistant to Gaviscon and Ranitidine. Past medical history is unremarkable, and she quit smoking 20 years ago. She has lost 4kgs over the last 5 months. Abdominal examination today is unremarkable.
Based on the likely diagnosis, what is the most appropriate management step?