Does cholecystectomy affect colonic tumorigenesis?
M. S. Hickman, H. C. Salinas and W. H. Schwesinger
To determine if cholecystectomy predisposes to colon cancer, & study of
this operation's influence on chemically induced murine colonic neoplasia
was conducted. One hundred mice underwent cholecystectomy or a sham
operation. Equal groups received either ten weekly injections of
1,2-dimethylhydrazine (DMH) or injections of saline. Twenty-four weeks
after operation, the site, histologic findings, and number of tumors were
noted. Crypt metaphase index (CMI) and proliferative zone size (PZS)
determinations served as markers of preneoplasia. Tumors were found in the
majority of animals receiving DMH while no tumors were found in the saline
groups. Both CMI and PZS were significantly increased by DMH
administration. Within the saline group, cholecystectomy increased CMI and
PZS two and three times, respectively, over levels seen in the
sham-operated animals. This suggests that cholecystectomy alone induces
preneoplastic changes in the murine colonic crypt.
