The goal of this observational study is to learn about early recurrence after curative-intent surgery for pancreatic cancer. The main questions it aims to answer are:

• How often does early recurrence (within 12 months after surgery) occur?
• When does it happen, and at which anatomical sites (liver, lung, local, peritoneum)?
• How is recurrence detected (imaging or tumor markers)?

Adults with histologically confirmed pancreatic ductal adenocarcinoma who undergo curative-intent resection without distant metastases will be enrolled. Participants will be followed according to routine clinical care at each hospital, typically with imaging and CA19-9 blood tests. No study-specific interventions are required.

This international, prospective, multicenter observational study aims to characterize early recurrence (ER) after curative-intent resection of pancreatic ductal adenocarcinoma (PDAC). ER is defined as recurrence occurring within 12 months following surgery.

The study will assess the incidence, timing, anatomical sites, and detection mode (radiologic vs. biochemical) of ER, as well as post-recurrence treatment patterns and short-term outcomes. Secondary aims include comparison between neoadjuvant and upfront surgery cohorts, evaluation of biochemical-only recurrence, and identification of clinical or pathological factors predictive of ER.

Consecutive eligible patients will be enrolled from high-volume pancreatic surgery centers worldwide and followed according to institutional standards of care, typically involving routine imaging and CA19-9 surveillance. Standardized data will be prospectively collected to describe recurrence patterns and post-recurrence management. No study-specific interventions are required.

Inclusion Criteria:

• Age ≥18 years
• Histologically confirmed pancreatic ductal adenocarcinoma (PDAC)
• Undergoing curative-intent resection (R0 or R1)
• No evidence of distant metastasis at the time of surgery
• Availability of preoperative CA19-9 value and pancreas-protocol CT or MRI
• Ability to provide written informed consent

Exclusion Criteria:

• Withdrawal of informed consent
• Pathological diagnosis other than PDAC (e.g., neuroendocrine tumor, acinar cell carcinoma, invasive IPMN)
• Surgery performed for palliative or diagnostic purposes only
• Intraoperative discovery of unresectable disease or distant metastases
• Gross residual disease (R2 resection)
• Incomplete clinical or radiologic follow-up precluding recurrence assessment
• Absence of adequate preoperative contrast-enhanced pancreas-protocol CT or MRI preventing accurate staging and metastatic evaluation
• Interval >9 months between two consecutive follow-up visits
• Major protocol deviations or insufficient data, as judged by the site investigator

Adult patients (≥18 years) with histologically confirmed pancreatic ductal adenocarcinoma undergoing curative-intent resection (R0 or R1) without evidence of distant metastases at the time of surgery. Both patients treated with neoadjuvant therapy and those undergoing upfront surgery are eligible.