Standard versus extended lymphadenectomy associated with pancreatoduodenectomy in the surgical treatment of adenocarcinoma of the head of the pancreas. - Pedrazzoli,S.; DiCarlo,V.; Dionigi,R.; Mosca,F.; Pederzoli,P.; Pasquali,C.; Kläppel,G.; Dhaene,K.; Michelassi,F.; and the lymphadenectomy study,g.roup. (Ann Surg, 1998)