Table 2.

The association between MOR mRNA expression and clinicopathological features overall.

Response variable	Adjusted OR	95% CI	P-value
AJCC TNM stage	1.135	0.978-1.318	0.096
Grade	1.011	0.846-1.207	0.908
AJCC-T	1.176	1.022-1.354	0.024
AJCC-N	1.145	0.975-1.346	0.101
AJCC-M	1.548	1.095-2.189	0.013

MOR (+) represented positive MOR mRNA expression; MOR (-) represented negative MOR mRNA expression; Young, under 60 years old; Old, over 60 years old; All the variables were described as frequencies and percentages, except for age described as mean and standard deviation.

TCGA, the Cancer Genome Atlas; MOR, mu opioid receptor; AJCC, the American Joint Committee on Cancer; TNM, Tumor node metastasis.