Owing to the recent advances in surgical techniques and postoperative care, the operative indication for adenocarcinoma of the pancreas has been widened in Japan. In our institution, we have extended lymphatic and connective tissue clearance during surgical resection of this cancer. As a result, the 5-year survival rate has increased from 8% to 25% due to a significant decrease in the incidence of locoregional recurrence. The prognostic benefit gained by this procedure is seen mainly in those patients with stage III cancer or in whom no positive nodes were detected beyond the pancreatic head region. Thus, our extended surgery seems to have been useful due to eradicating the microinvasion in the peripancreatic connective tissues, rather than dissecting the positive lymph nodes. More advanced cancers should be treated by effectively combining chemo- and/or radiation-therapies with surgery. In order to cure the patients more easily with less-invasive surgery in the future, we should develop both an early diagnosis system and sensitive examinations of micrometastases or microinvasions.