Table 3. Clinicopathological and molecular features of rectal carcinoid tumors by miR-885-5p expression.
| Clinicopathological and molecular feature | Total | miR-885-5p | P | |
|---|---|---|---|---|
| Low expression | High expression | |||
| All cases | 56 | 51 | 5 | |
| Gender | ||||
| Male | 29 (52%) | 26 (51%) | 3 (60%) | 0.70 |
| Female | 27 (48%) | 25 (49%) | 2 (40%) | |
| Age (mean ± SD) | 58.9 ± 13.9 | 57.2 ± 6.2 | 59.1 ± 1.9 | 0.78 |
| Tumor size (mm) (mean ± SD) | 6.2 ± 2.5 | 7.0 ± 1.1 | 6.1 ± 0.35 | 0.44 |
| Lymphovascular invasion | ||||
| Negative | 43 (77%) | 43 (84%) | 0 (0%) | <0.0001 |
| Positive | 13 (23%) | 8 (16%) | 5 (100%) | |
| CDKN2A (p16) | ||||
| Unmethylated | 38 (68%) | 36 (71%) | 2 (40%) | 0.18 |
| Methylated | 18 (32%) | 15 (29%) | 3 (60%) | |
| IGF2 | ||||
| Unmethylated | 49 (87%) | 46 (90%) | 3 (60%) | 0.097 |
| Methylated | 7 (13%) | 5 (9.8%) | 2 (40%) | |
| MINT1 | ||||
| Unmethylated | 28 (50%) | 25 (49%) | 3 (60%) | 0.64 |
| Methylated | 28 (50%) | 26 (51%) | 2 (40%) | |
| MINT2 | ||||
| Unmethylated | 41 (73%) | 38 (75%) | 3 (60%) | 0.50 |
| Methylated | 15 (27%) | 13 (25%) | 2 (40%) | |
| MINT31 | ||||
| Unmethylated | 22 (39%) | 20 (39%) | 2 (40%) | 0.97 |
| Methylated | 34 (61%) | 31 (61%) | 3 (60%) | |
| MLH1 | ||||
| Unmethylated | 53 (95%) | 50 (98%) | 3 (60%) | 0.0090 |
| Methylated | 3 (5.3%) | 1 (2.0%) | 2 (40%) | |
| CIMP status | ||||
| Negative | 7 (13%) | 5 (9.8%) | 2 (40%) | 0.098 |
| Positive | 49 (87%) | 46 (90%) | 3 (60%) | |
Percentage (%) indicates the proportion of cases with a specific clinicopathological or molecular feature according to miR-885-5p expression status. CIMP positivity was defined as the presence of four or more of the six methylated promoters [CDKN2A (p16), IGF2, MINT1, MINT2, MINT31, and MLH1]. P-values were calculated by t-test for age and tumor size and by a chi-square test or Fisher's exact test for all other variables.
CIMP, CpG island methylator phenotype; miR-885, microRNA-885; SD, standard deviation.