Positive Health Online

Abstract

CASCINU and colleagues, Section of Experimental Oncology, Azienda Osedaliera S. Salvatoire, Pesaro, Italy set out to investigate calcium and vitamin supplementation on colorectal cell proliferation.

Background

Calcium and anti-oxidant vitamins such as A, C and E have been shown to reduce colorectal epithelial proliferation and therefore may be chemoprotective in colorectal cancer.

Methodology

Ninety patients with resected colorectal cancer were enrolled in a randomized clinical trial (RCT) in which they received (daily for 6 months) either a combination of vitamin A (30,000 IU), vitamin C (1g), vitamin E (70mg) and calcium (2g) or an indistinguishable placebo. Cell proliferation of the normal colonic mucosa was assessed at time of surgery, 6 and 12 months using the antibody to proliferating cell nuclear antigen (PCNA) and a mean total PCNA labelling index was calculated (PCNALI).

Results

Of the 90 patients enrolled, 34 of the treatment group and 43 of the placebo group were assessable. After both 6 and 12 months the PCNALI was reduced in both groups compared to baseline with a slight advantage to treatment group at 6 months (treatment 34%, placebo 28%). However there was no statistically significant differences, either compared with baseline or between groups.

Conclusion

This RCT shows that dietary calcium and vitamins A, C and E does not reduce cell kinetics of colon epithelium in patients with colorectal cancer and highlights the importance of control groups in such trials.

References

Cascinu S et al. Effects of calcium and vitamin supplementation on colon cell proliferation in colorectal cancer. Cancer Investigation 18(5): 411-6. 2000.