The signature generalizes to external cohorts of gemcitabine-treated patients but not untreated patients
(A) Kaplan-Meier curves describing DSS among patients receiving adjuvant gemcitabine-based therapy in the UPMC cohort (n = 46) when stratified by the histologic signature. The p value (p = 0.02) corresponds to the log rank test. Median DSS of signature+ patients was 43.1 months (95% CI: [26.8, 63.9]), and the median DSS of signature− patients was 16 months (95% CI: [10.8, 50.1]).
(B) Kaplan-Meier curves describing DSS among patients in the UPMC cohort who had received no therapy prior to surgery (n = 24) (log rank test p = 0.03). Median DSS of signature+ patients was 40.2 months (95% CI: [16.4, not reached]), and the median DSS of signature− patients was 12.9 months (95% CI: [8.1, not reached]).
(C) Kaplan-Meier curves describing time to recurrence among patients who received adjuvant gemcitabine-based therapy (n = 46) (log rank test p = 0.01). Median time to recurrence of signature+ patients was 22.6 months (95% CI: [14.1, 44.8]), and the median time to recurrence among signature− patients of 9.1 months (95% CI: [6.4, 14.7]).
(D) Kaplan-Meier curves describing DSS among patients in the Copenhagen cohort who were untreated (log rank test p = 0.59; signature+ median DSS: 13.2 months [10.4, 19.8], signature− median DSS: 12.3 [10.4, 19.8]).