Table 2.
Association of clinicopathologic parameters with Her2 and Ki-67 expression using multivariable-adjusted logistic regression
| Variable | Her2 | Ki-67 | ||
|---|---|---|---|---|
| OR (95% CI) | P | OR (95% CI) | P | |
| Sex | ||||
| Male | 1 (reference) | 1 (reference) | ||
| Female | 0.72 (0.36–1.46) | 0.360 | 0.75 (0.39–1.47) | 0.405 |
| Age (as continuous) | 1.01 (0.97–1.04) | 0.705 | 1.03 (1.00–1.06) | 0.092 |
| Tumor location | ||||
| Gastric cardia and fundus | 1 (reference) | 1 (reference) | ||
| Gastric body | 1.59 (0.75–3.37) | 0.544 | 1.51 (0.72–3.17) | 0.983 |
| Gastric antrum and pylorus | 1.05 (0.51–2.20) | 0.647 | 1.05 (0.52–2.13) | 0.367 |
| Tumor differentiation | ||||
| Well/moderate | 1 (reference) | 1 (reference) | ||
| Poor/undifferentiated | 0.25 (0.12–0.53) | < 0.001 | 1.10 (0.53–2.26) | 0.806 |
| Neural invasion | ||||
| No | 1 (reference) | 1 (reference) | ||
| Yes | 2.35 (1.01–5.48) | 0.048 | 0.75 (0.33–1.70) | 0.487 |
| Tumor thrombosis | ||||
| No | 1 (reference) | 1 (reference) | ||
| Yes | 1.24 (0.56–2.75) | 0.601 | 0.96 (0.44–2.08) | 0.917 |
| Tumor length (as continuous) | 1.09 (0.93–1.29) | 0.276 | 0.97 (0.83–1.13) | 0.700 |
| pT stage | ||||
| 1 | 1 (reference) | 1 (reference) | ||
| 2 | 1.39 (0.41–4.67) | 0.134 | 0.94 (0.27–3.20) | 0.559 |
| 3–4 | 0.26 (0.08–0.85) | 0.001 | 0.50 (0.16–1.54) | 0.128 |
| pN stage | ||||
| 0 | 1 (reference) | 1 (reference) | ||
| 1 | 2.69 (1.09–6.62) | 0.030 | 1.42 (0.61–3.30) | 0.673 |
| 2 | 2.71 (1.14–6.43) | 0.027 | 1.20 (0.54–2.66) | 0.867 |
| 3 | 2.83 (1.17–6.87) | 0.016 | 1.46 (0.65–3.31) | 0.559 |
Her2 and Ki-67 are in the sequential order of −, +, ++ , and +++. The positivity degree of Her2 expression follows the National Comprehensive Cancer Network (NCCN) Guidelines (https://www.nccn.org): − means “no reactivity or membranous reactivity in < 10% of cancer cells”; + means “faint or barely perceptible membranous reactivity in ≥ 10% of cancer cells; cells are reactive only in part of their membrane”; ++ means “weak to moderate complete, basolateral or lateral membranous reactivity in ≥ 10% of cancer cells”; +++ means “strong complete, basolateral, or lateral membranous reactivity in ≥ 10% of cancer cells”. – or + expression indicates a negative result, and +++ expression suggests a positive finding. In case of ++ expression by immunohistochemistry, in situ hybridization was further performed, and cases with an average Her2 copy number ≥ 6.0 signals/cell are considered positive. For Ki-67, − means very low proliferation activity with proportion of Ki-67-positive cells < 25%; + means low proliferation activity with proportion of Ki-67-positive cells 25–50%; ++ means moderate proliferation activity with proportion of Ki-67-positive cells 50–75%; +++ means high proliferation activity with proportion of Ki-67-positive cells > 75%. A section was regarded negative in Ki-67 expression with < 50% positive cells, and positive with ≥ 50% positive cells. Significant associations are shown in italics
pT stage pathological tumor stage, pN stage pathological node stage, Her2 human epidermal growth factor receptor 2; OR odds ratio, CI confidence interval