SummaryIn the present study an attempt has been made to indicate the different types of radionuclide subtraction scan patterns that can occur in carcinoma of the pancreas. A follow up was made of 44 consecutive patients with established clinical or proven histological diagnosis of carcinoma of the pancreas from a total series of 800 who were presented for radionuclide subtraction scanning. The study does not attempt to analyse results in pancreatic carcinoma but merely to indicate the type of scan presentations which can occur. It was interesting to find that more than one third of the patients studied presented with an uptake of75Se Selenomethionine in the tumour region and only a small number of the series revealed the tumour by a filling defect in an otherwise normal pancreatic scan. Despite the differing scan presentations of carcinoma of the pancreas it was generally not possible on the scan alone to differentiate a benign from a malignant lesion. but in each case the scan was clearly abnormal and when taken within the clinical context could well represent a carcinoma.