MSFinals-6159

A 68-year-old man presents with a three-month history of typical dyspepsia symptoms, including epigastric pain and a 2-stone weight loss. Despite treatment with a proton pump inhibitor, he has not experienced any relief. He now reports difficulty eating solids and frequent post-meal vomiting. On examination, a palpable mass is found in the epigastrium. His full blood count shows a haemoglobin level of 85 g/L (130-180). What is the probable diagnosis?