Table 1.

Quantitative assessment of CaSR immunoreactivity in normal colonic crypt epithelium and colon carcinoma.

Histological features	% positive cells	Staining intensity
Normal colonic crypt epithelium (n=9)
Basal zone	6±1	1.1±0.1
Mid-crypt	90±5**	2.3±1.5*
Surface	96±2**	2.9±1.0**
Well- to moderately-differentiated tumor (n=7)	63±13	1.7±0.7
***Poorly- to undifferentiated tumor (n=4)	3±1**	1.1±0.1**

Normal colon: Basal zone - base of the crypt containing small, densely-packed cells without evidence of goblet cell structure. Mid-crypt - area from the edge of the basal zone to an area 1/3 of the way from the top of the crypt. Surface zone - upper 1/3 of the crypt and the cells at the apex of the crypt. Values are means and standard errors based on four separate areas in each specimen.

^*indicates statistically-significant difference from basal zone at p<0.05 level.

^**indicates statistically-significant difference from basal zone at p<0.01 level.

Colon carcinoma: Well- to moderately-differentiated tumor - evidence of glandular structure. Poorly- to undifferentiated tumor - areas in which only cell sheets were detected (i.e., no glandular structure). Values are means and standard errors based on four separate areas in each specimen.

^***indicates statistically-significant difference from well- to moderately-differentiated tumor at p<0.01 level.

***includes small clusters of tumor cells (1-3 cells) at the invasive front; imbedded in the stroma with no evidence of glandular structure.