Out of 63 Japanese patients with pancreatic carcinoma who underwent surgical resection, 8 short-term survivors who died within 3 months after resection and 6 long-term survivors who were alive for more than 3 years after resection were compared regarding 26 clinicopathological parameters. The 8 short-term survivors were significantly older than the 6 long-term survivors (63.7 versus 47.8 years, P = 0.0099). The mean peripheral lymphocyte count was significantly smaller in the short-term survivors than in the long-term survivors (1,212 versus 2,115 /microl, P = 0.0459). Operative blood loss was significantly larger in the short-term survivors than in the long-term survivors (2,393 versus 1,043 g, P = 0.0157). The surgical margin was affected by malignant cells in 7 of the 8 short-term survivors, but in only 2 of the 6 long-term survivors (P = 0.0362). Of the 8 short-term survivors, 5 were in comprehensive stage IV and 3 in stage III, while 3 of the 6 long-term survivors were in stage III, two in stage II, and one in stage I (P = 0.0487). All the 8 short-term survivors were of the comprehensive curability C, while 3 of the 6 long-term survivors were of A, one B and the other two C (P = 0.0239). Multiple regression analysis of these 6 profound factors showed that the peripheral lymphocyte count was an independent significant parameter to differentiate the short-term and long-term survivors. These findings suggest that, although the aggressive nature of pancreatic cancer has been accepted, the clinical course after pancreatectomy would also depend upon the immunological state of the patient.