We investigated the relation between the plasma levels of various proteins, especially rapid turnover proteins (RTPs), and the prognosis in advanced cancer patients receiving total parenteral nutrition (TPN). In the patients with benign disease (n = 40), RTPs increased abruptly following TPN, but in patients with malignant disease, they rose slowly. Patients with malignant disease were divided into two different groups according to the outcome; group A, surviving 3 months or more after TPN and group B, who died within 3 months after TPN initiation. Whereas the RTP levels were elevated significantly in group A, they did not show any noticeable increase in group B. There was a close correlation between the plasma protein levels at 2 weeks and the survival time after TPN initiation. Thus, using the estimated critical values of RTPs with prognostic significance, the correct prognosis rate in 37 newly treated cases was: transferrin 75.7%, prealbumin: 91.9%, retinol-binding protein: 86.5%. These results clearly indicate that the TPN-induced changes in RTPs, notably in the PA value, can be a good prognostic indicator of survival in advanced cancer patients.