Rapid Deterioration of Glycaemic Control Revealing Interval Metastatic Pancreatic Cancer Despite a Recent Normal CT Scan

New-onset diabetes in the elderly or acute deterioration of glycaemic control in already known diabetics is sometimes linked with suspicion of pancreatic malignancy. We report the case of an 81-year-old woman with long-standing, type 2 diabetes, well-controlled on gliclazide, who developed worsening glycaemic control over four months. A contrast-enhanced CT scan performed for an unrelated indication four months earlier was reported as normal. She presented with symptomatic hyperglycaemia with acutely deranged capillary blood sugar levels and a markedly elevated glycosylated haemoglobin (HbA1c), without evidence of infection or other precipitating factors. Repeat imaging demonstrated a necrotic pancreatic mass with metastatic disease and concurrent saddle pulmonary embolism. This case demonstrates that pancreatic malignancy may become apparent despite previously normal imaging and illustrates the diagnostic challenge when longstanding diabetes suddenly deteriorates.