Table 4.

Tumor PDCD1LG2 (PD-L2) expression and colorectal cancer mortality

Colorectal cancer–specific mortalityOverall mortality
Fraction of PDCD1LG2-expressing tumor cellsaTotal no.No. of eventsUnivariable HR (95% CI)Multivariable HR (95% CI)bNo. of eventsUnivariable HR (95% CI)Multivariable HR (95% CI)b
Quartile 1207711 (reference)1 (reference)1221 (reference)1 (reference)
Quartile 2185580.87 (0.61–1.23)0.99 (0.70–1.41)1060.93 (0.71–1.20)1.03 (0.79–1.34)
Quartile 3246630.70 (0.50–0.98)0.68 (0.48–0.95)1300.85 (0.67–1.09)0.84 (0.65–1.07)
Quartile 4179590.92 (0.65–1.31)0.95 (0.67–1.34)950.85 (0.65–1.11)0.88 (0.67–1.15)
Ptrendc0.350.260.170.14
  • aTumors were categorized into quartiles according to the percentage of PDCD1LG2–expressing carcinoma cells (quartile 1, 0%–20%; quartile 2, 21%–50%; quartile 3, 51%–80%; quartile 4, 81%–100%).

  • bThe multivariable Cox regression model initially included age, sex, year of diagnosis, family history of colorectal carcinoma in any parent or sibling, tumor location, disease stage, MSI, CpG island methylator phenotype, KRAS, BRAF, and PIK3CA mutations, and LINE-1 methylation level. A backward elimination with a threshold of P = 0.05 was used to select variables in the final models.

  • cPtrend value was calculated across the ordinal quartile categories of tumor PDCD1LG2 expression (1–4) as a continuous variable in the Cox regression models.