Discovery Cohort - NAC Responder Group

Patients with resectable or borderline resectable pancreatic ductal adenocarcinoma (PDAC) who received neoadjuvant chemotherapy (FOLFIRINOX or gemcitabine plus nab-paclitaxel) and achieved a clinical or pathological response.~Responders were defined as patients showing complete response (CR), partial response (PR), or stable disease (SD) according to radiologic or pathologic assessment after NACT.~Pre-treatment plasma samples from these patients were analyzed by small RNA sequencing to identify microRNAs associated with favorable chemotherapy response.

Discovery Cohort - NAC Non-Responder Group

Patients with resectable or borderline resectable PDAC who received neoadjuvant chemotherapy but demonstrated progressive disease (PD) on radiologic or pathologic evaluation.~Pre-treatment plasma samples from these patients were analyzed in parallel by small RNA sequencing to identify differential miRNA expression compared with responders.

Training Cohort - NAC Responder Group

PDAC patients treated with neoadjuvant chemotherapy (FOLFIRINOX or gemcitabine plus nab-paclitaxel) who achieved CR, PR, or SD responses.~Candidate microRNAs identified in the Discovery cohort were validated using qRT-PCR (PRECEPT assay).~Responder group data were used to train and optimize the predictive miRNA panel.

Training Cohort - NAC Non-Responder Group

PDAC patients who received neoadjuvant chemotherapy but exhibited progressive disease (PD).~Plasma miRNA expression was measured using the PRECEPT assay and compared with responders to refine the predictive model for chemotherapy response.

Validation Cohort - NAC Responder Group

A separate validation cohort of PDAC patients treated with neoadjuvant chemotherapy who achieved CR, PR, or SD.~The established PRECEPT miRNA panel (qRT-PCR) was applied to evaluate predictive accuracy in this independent responder group.

Validation Cohort - NAC Non-Responder Group

Independent PDAC patients who received neoadjuvant chemotherapy and demonstrated progressive disease (PD).~This cohort was used to confirm the predictive performance and robustness of the PRECEPT miRNA assay compared with responders.