[Modified surgical treatment of tumors]

Reduced operation is generally considered to make an operative damage smaller than that of standard operation among various techniques used for the surgical treatment of solid cancer. The factors of recent increases in reduced operation cases are: 1) increases in the detection of early cancers; 2) improvement of the understanding of cancer cell spread; 3) reconsideration of standard operation as well as extensive operation; 4) development of effective combined therapy; 5) increases in aged patients; and 6) demands for functional conservation.