Long-term survivors after resection of carcinoma of the head of the pancreas: significance of histologically curative resection

Background/Purpose. The prognosis of patients with pancreatic cancer is said to have not been improved markedly by any procedures in the past 20 years. Since 1973, we have gradually extended the area of dissection when performing curative resection for pancreatic cancer to improve the resection rate and prognosis. Nineteen patients have survived for 3 years or more, and the 5-year survival rates of patients with cancer of the head of the pancreas were 23.9% for macroscopically curative resection and 34.3% for histologically curative resection. Methods. We histologically observed surgical specimens, cut into 3- to 5-mm sections and compared the histologic characteristics of the 19 patients who survived for 3 years or more with those of 41 patients who died of cancer within 3 years (excluding 6 operative and hospital deaths), in order to find the conditions required for long-term survival. Results. The following conditions were associated with long-term survival: (1) tumor diameter 3 cm or less; (2) either absence of lymph node metastasis or metastasis limited to the n(1) group; (3) degree of invasion of the anterior pancreatic capsule of zero (s0); and (4) either no retropancreatic invasion (rp0) or exposed retropancreatic invasion (rpe) with no cancer invasion of dissected peripancreatic tissue ew(-). Conclusions. At present, because the rpe rate is more than 70%, resection of the pancreas, including the superior mesenteric vein and the retropancreatic fusion fascia, is essential for a curative resection, because the retropancreatic tissue between the back of the pancreas and this fascia is anatomically considered to be in the position of the subserosal tissue in the gallbladder or stomach. Combined resection of the superior mesenteric artery may further improve the results of resection for pancreatic cancer, from the anatomical viewpoint.