Table 3.

Bivariate (Spearman ρ) correlations between tumour burden and metabolite level in 17 patients with pancreatic adenocarcinoma

	Correlation with maximal tumour diameter	Correlation with percentage of positive lymph nodes
Tryptophan	P = 0.567	P = 0.327
Kynurenine	P = 0.021, ρ = −0.554	P = 0.034, ρ = 0.515
Kynurenic acid	P = 0.970	P = 0.347
Quinolinic acid	P = 0.047	P = 0.339
Tryptophan : kynurenine ratio	P = 0.083	P = 0.796
Kynurenic acid : tryptophan ratio	P = 0.779	P = 0.800
Quinolinic acid : tryptophan ratio	P = 0.132	P = 0.915