Table 3.

Performance of DAS in the Validation Set

Variable	P	AUC	95% CI
Total	< .001	0.650	0.585 to 0.716
Sex
Female	.3057	0.563	0.434 to 0.692
Male	< .001	0.692	0.620 to 0.765
Smoking status
Current smoker	< .001	0.652	0.569 to 0.735
Former smoker	.0151	0.644	0.537 to 0.750
Histology
Adenocarcinoma	.3084	0.557	0.448 to 0.667
SCC	.0063	0.658	0.547 to 0.769
Other NSCLC	< .001	0.754	0.643 to 0.865
Stage
I and II	.0124	0.675	0.546 to 0.804
III and IV	< .001	0.693	0.613 to 0.773
Timing of blood draw, months
0-6	< .001	0.740	0.634 to 0.846
> 6-12	.0409	0.588	0.505 to 0.671

Abbreviations: AUC, area under the curve; DAS, N¹,N¹²-diacetylspermine; NSCLC, non–small-cell lung cancer; SCC, squamous cell carcinoma.