A total of 161 primary contrast-enhanced computed tomography (CT) scans of patients with acute necrotizing pancreatitis taken between 1982 and 1994 were analysed retrospectively. The aim was to assess the prognostic significance of the extent and anatomical site of pancreatic tissue necrosis in the first contrast-enhanced CT scan. The scans were obtained a mean of 2.9 days after the onset of symptoms. The pancreatic head was affected in 107 patients, the body in 119 and the tail in 138. Pancreatic tissue necrosis, when divided into four groups according to anatomical site, correlated with overall clinical outcome. The anatomical site of necrosis was clearly better than its crude extent in predicting the risk of complications. For patients with necrosis in the head of the pancreas, the outcome was as severe as when the entire pancreas was affected. In contrast, for patients with necrosis only in the distal part of the pancreas, the outcome was favourable with few complications. The exact site of pancreatic tissue necrosis should be known when early contrast-enhanced CT is used in prognostic scoring.