Weight loss and the acute-phase response have been associated with poor quality of life and survival in advanced pancreatic cancer; however, little information is available on changes in these factors over time and their interrelationships. This study examined changes in weight, Karnofsky performance status, C-reactive protein (CRP), and serum albumin in 25 patients with advanced pancreatic cancer given supportive symptomatic treatment only. Patients were assessed at approximately monthly intervals on a total of 70 occasions, allowing assessment of changes over 37 intervals. Overall, patients had a median weight loss of 2.3 kg/28 days. Median CRP levels rose by 15 mg/l, and serum albumin fell by 1 g/l on average over 28 days. Karnofsky performance status fell by 4 points every 28 days. The nine patients assessed close to death were compared with the 13 assessed close to diagnosis. The increase in CRP level and fall in weight and performance status were significantly greater within eight weeks of death than within eight weeks of diagnosis. Among patients close to diagnosis, 13% had an elevated CRP compared with 100% of those close to death. In multivariate analysis, Karnofsky performance status was significantly associated with percent weight loss and CRP levels. These data further implicate the acute-phase protein response as being associated with the progressive weight loss seen in patients with advanced pancreatic cancer. Changes appear to accelerate close to death. Moreover, the development of cachexia is associated with a reduction in patients' functional capacity.