Performance of a modified 3-level classification in stratifying open liver resection procedures in terms of complexity and postoperative morbidity. (March 2019) - Kawaguchi, Y.; Hasegawa, K.; Tzeng, C.D.; Mizuno, T.; Kokudo, T.; Arita, J.; Sakamoto, Y.; Chun, Y.S.; Aloia, T.A.; Kokudo, N.; Vauthey, J.N.