This study investigates how often pancreatic cancer returns within 12 months after surgery. Patients who had surgery to remove cancer without it spreading elsewhere can join. The study tracks when the cancer returns, where it appears (like in the liver or lungs), and how doctors find it using scans or blood tests. The study involves no extra treatments or procedures; it follows normal hospital check-ups.

• **No extra treatment needed:** You just need to attend your regular hospital visits.
• **Eligibility:** Adults over 18 with pancreatic ductal adenocarcinoma who had surgery to remove the cancer.
• **Follow-up period:** You will be monitored for 12 months after surgery.

Participants must have a confirmed diagnosis of pancreatic ductal adenocarcinoma and no distant cancer spread. They need to undergo surgery aimed at curing them (R0 or R1 resection), have a blood test result for a marker called CA19-9, and be able to consent. The study will help doctors understand how often and quickly cancer returns, which can improve future treatment strategies.