28th February 2025

A 65 year-old-man has been treated for localised prostate cancer. He underwent radical external beam

A 65 year-old-man has been treated for localised prostate cancer. He underwent radical external beam radiotherapy of the prostate alongside Goserelin (Zoladex). He began to feel constantly nauseous one week following starting radiotherapy. Two weeks following radiotherapy, he is now opening his bowels 4 times per day and has abdominal cramping. He has no vomiting, weight loss, rectal bleeding or fevers. What is the gold-standard investigation when diagnosing the underlying cause for these symptoms?

Select the SINGLE most appropriate option from the list below. Select ONE option only.