Table 4. Association of melanosis coli with detecting rates of colonic polyps of different histological types.
| Groups | Detecting rates of colonic polyps of different histological types | ||
|---|---|---|---|
| Inflammatory or hyperplastic polyp | Low grade adenoma | Advanced adenoma or adenocarcinoma | |
| Melanosis coli (n = 219) | 44 (20.1%) | 67 (30.6%) | 11 (5.0%) |
| Control (n = 438) | 56 (12.8%) | 101 (23.1%) | 26 (5.9%) |
| Odds ratio, 95% CI | 1.57 (1.10–2.25) | 1.33 (1.03–1.73) | 0.88 (0.44–1.75) |
| p value | 0.01* | 0.04* | 0.63 |
| Degrees of melanosis coli: | |||
| Grade I (n = 137) | 29 (21.2%) | 42 (30.7%) | 7 (5.1%) |
| Grade II (n = 55) | 9 (16.4%) | 14 (25.5%) | 5 (9.1%) |
| Grade III (n = 27) | 6 (22.2%) | 12 (44.4%) | 0 (0%) |
| p value | 0.72 | 0.22 | 0.11 |
| Distribution of melanosis coli: | |||
| Right colon (n = 56) | 9 (16.1%) | 16 (28.6%) | 2 (3.6%) |
| Left colon (n = 38) | 12 (31.6%) | 10 (26.3%) | 5 (13.2%) |
| Total colon (n = 125) | 23 (18.4%) | 42 (33.6%) | 4 (3.2%) |
| p value | 0.14 | 0.63 | 0.04* |
*p<0.05