[Changes of sphincter preserving rate in lower rectal cancer and analysis of their related factors]

To analyze the factors related to sphincter preserving(SP) operation for lower rectal cancer.

Clinicopathological data of 316 patients with lower rectal cancer 1-5 cm from the anorectal line who underwent surgical resection from Aug. 1994 to Nov. 2005 were analyzed. The whole period was divided into two period based on the introduction of TME in Jan. 1999. The SP rates, leakage between the two period were compared.

The SP rate increased significantly from 44.9 % in period I (Aug. 1994-Dec. 1998) to 76.2 % in period II (Jan. 1999-Nov. 2005)(P=0.000). The factors significantly influencing SP were the distance from the anorectal line, sex, period, circumference of intramural spread, histological differentiation (P< 0.05). Significant differences were detected between the two period in sex, volume of blood transfusion, Dukes' stage (P< 0.05). The rate of leakage were 2.7 % and 1.3 % in the two period (P > 0.05).

Over 12 years, the SP rate of rectal cancers 1-5 cm from the anorectal line was significantly increased and volume of blood transfusion reduced obviously due to the introduction of TME. These surgical techniques, however, have no effect on the operating time and leakage rates.