Inhibitory effect of calcium on carcinogenesis at the site of colonic anastomosis: an experimental study.
OBJECTIVE
A study was made to assess the effect of oral calcium supplementation on colorectal carcinogenesis at the colocolic suture line and in the rest of the colon following administration of a carcinogen.


METHODS
Fifty-nine rats were randomly divided into two groups: control (given a standard diet for rats and mice containing 0.8 percent calcium) and treatment (given the same diet as before but with 2 percent calcium). Carcinogenesis was induced by 26 weekly injections of 1,2-dimethylhydrazine. All animals were subjected to an end-to-end colonic anastomosis at the beginning of the experiment using five stitches of steel wire.


RESULTS
The control group developed significantly more tumors per animal at both the anastomosis (P < 0.001) and in the rest of the colon (P < 0.001). In addition, the percentage of rats with tumors was significantly higher in the control group at both the anastomosis (chi-squared = 12; df = 1, P < 0.001) and in the rest of the colon (chi-squared = 7.12; df = 1, P < 0.01). The mean surface of tumors was likewise greater in the control group at the anastomosis (P < 0.001) and throughout the rest of the colon (P < 0.001). Finally, there were significantly more small-bowel tumors (excluding the duodenum) in the control group (P < 0.05).


CONCLUSIONS
It is concluded that calcium supplementation decreases the tumor yield at the site of end-to-end colonic anastomosis and in the rest of the colon and small bowel (excluding the duodenum).
Adell-Carceller
R
R
Service of Surgery, Castellón General Hospital, Spain.
Segarra-Soria
M
M
Gibert-Jerez
J
J
Salvador Sanchís
J L
JL
Lázaro-Santander
R
R
Escrig-Sos
J
J
Ruiz-Castillo
J
J
D000230:Adenocarcinoma / Q000209:etiology / Q000517:prevention & control*; D000714:Anastomosis, Surgical; D000818:Animals; D002136:Calcium, Dietary / Q000494:pharmacology*; D003106:Colon / Q000187:drug effects / Q000601:surgery*; D003110:Colonic Neoplasms / Q000209:etiology / Q000517:prevention & control*; D004195:Disease Models, Animal; D006801:Humans; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013193:Stainless Steel; D013537:Sutures
D002136:Calcium, Dietary; D013193:Stainless Steel