Overview

The goal of this prospective observational study is to learn about the clinical utility of dynamic ctDNA-based Minimal Residual Disease (MRD) monitoring in patients with borderline resectable pancreatic cancer undergoing neoadjuvant therapy. The main questions it aims to answer are:

1. Does MRD negativity correlate with improved surgical outcomes (R0 resection rates) and long-term survival (Disease-Free Survival [DFS] / Overall Survival [OS])?
2. Can serial MRD status assessments guide optimal neoadjuvant therapy duration? Participants (n=119) will be adults aged 18-75 years with histologically confirmed pancreatic cancer meeting NCCN criteria for borderline resectable/high-risk resectable/locally advanced disease, deemed eligible for neoadjuvant therapy by a multidisciplinary team (MDT) and with ECOG performance status ≤1. Patients with distant metastasis, prior anticancer therapy, or concurrent malignancies are excluded.

During 24-month study period (12-month recruitment + 12-month follow-up), enrolled subjects will:

1. Receive standard-of-care neoadjuvant therapy/surgery per physician's decision.
2. Undo serial blood draws for ctDNA-MRD testing at predefined timepoints.
3. Be followed for DFS/OS outcomes for 18 months. This non-interventional study is conducted at Ruijin Hospital Pancreatic Surgery Department.

Eligibility

Inclusion Criteria:

• Subjects meeting ALL of the following criteria will be enrolled:
  1. Age and Gender :Aged 18-75 years, regardless of gender.
  2. Diagnosis and Disease Stage :

     Pathologically confirmed pancreatic cancer, meeting NCCN guideline criteria

     for

     1. High-risk resectable (meeting ≥1 criterion):
        1. Luminal stenosis of the portal vein or superior mesenteric vein on imaging;
        2. Radiographic stage T≥3 or N≥1;
        3. Serum CA19-9 ≥1000 U/mL (after resolution of jaundice);
        4. Confirmed regional lymph node metastasis;
        5. Significant weight loss (>10% baseline) or severe pain requiring opioids.
     2. Borderline resectable :
        1. Tumor involving the common hepatic artery without celiac axis contact;
        2. Tumor contact with SMA ≤180°.
     3. Locally advanced (unresectable):
        1. Tumor encasement (>180°) of the SMA, celiac axis, or common hepatic artery;
        2. Unreconstructable involvement of SMV/portal vein;
        3. No distant metastasis.

  3. Treatment Suitability :Deemed suitable for neoadjuvant therapy after

     multidisciplinary team (MDT) discussion .

  4. Performance Status :ECOG (Eastern Cooperative Oncology Group) performance status ≤1 .
  5. Life Expectancy :Estimated survival ≥6 months.
  6. Organ Function :No severe cardiac, hepatic, or renal dysfunction, including:

     ALT/AST ≤3×ULN (upper limit of normal); Serum creatinine ≤1.5×ULN .

  7. Informed Consent :Signed written informed consent voluntarily provided.

Exclusion Criteria:

• Subjects meeting ANY of the following criteria will be excluded:
  1. Distant Metastasis Radiographically confirmed distant metastatic lesions.
  2. Prior Anti-Tumor Therapy History of any prior anti-tumor treatment, including:

     Systemic chemotherapy Radiotherapy Interventional therapy Immunotherapy Targeted therapy Anti-tumor traditional Chinese medicine therapy.

  3. Concurrent Malignancy Diagnosis of other active malignancies.
  4. Pregnancy or Lactation Female subjects who are pregnant or breastfeeding.
  5. Drug Allergy Hypersensitivity to any agents in the guideline-recommended first-line neoadjuvant regimen .
  6. Transplantation History Prior allogeneic hematopoietic stem cell transplantation or solid organ transplantation .
  7. Immunodeficiency Disorders Congenital or acquired immunodeficiency, including:

Human Immunodeficiency Virus (HIV) infection;

Active Hepatitis B :

HBsAg-positive andHBV-DNA ≥10,000 copies/mL (≥2,000 IU/mL) at screening;

Active Hepatitis C :

HCV-Ab-positive andHCV-RNA positive at screening; Co-infection with HBV and HC