This study is for patients with advanced bile duct or pancreatic cancer who are experiencing pain from their disease. The purpose of this research is to learn about the effects of combining a standard pain relief treatment (Celiac Plexus Block) with standard first-line cancer drugs.

Patients in this study will receive the Celiac Plexus Block procedure, which is intended to reduce pain, and will then begin their standard cancer medication regimen. Researchers will observe and compare how well this combined approach works to control pain and the cancer itself, and will monitor for any side effects. Participation in this study involves being followed by the research team for up to 2 years to track health outcomes.

The goal is to see if starting cancer treatment together with this specialized pain management technique is more helpful for patients compared to what is already known about the standard treatments alone.

This is a prospective, observational, single-center cohort study designed to evaluate the clinical outcomes of integrating celiac plexus neurolysis (CPN) with standard first-line systemic therapy in patients diagnosed with advanced biliopancreatic malignancies and concomitant cancer-related pain.

Eligible participants are adults with histologically confirmed, inoperable advanced biliary tract cancer or pancreatic cancer, who present with moderate to severe abdominal pain and are candidates for first-line systemic treatment. All patients will be managed according to routine clinical practice; the decision to perform CPN and the choice of specific systemic therapy regimen will be determined by the treating physician team based on standard guidelines and individual patient circumstances, not by the study protocol.

The primary objective is to assess the efficacy of this integrated approach, with co-primary endpoints of pain response rate and objective tumor response rate. Pain response is defined as a reduction of ≥2 points in the Numeric Rating Scale score or a ≥50% decrease in opioid consumption sustained for ≥4 weeks. Tumor response will be evaluated per RECIST 1.1 criteria. Secondary objectives include comparing overall survival, progression-free survival, and quality of life metrics between the cohort receiving CPN combined with systemic therapy and a contemporary control cohort receiving systemic therapy alone. Safety will be assessed by monitoring the incidence and severity of adverse events related to both CPN and the systemic treatments.

Clinical data, including pain scores, analgesic usage, tumor imaging assessments, and laboratory results, will be prospectively collected at predefined time points for a follow-up period of up to 2 years. The study aims to provide real-world evidence on whether the early integration of interventional pain management with oncological treatment can improve overall patient outcomes in this population with high symptom burden.

Inclusion Criteria:

• Histologically confirmed advanced biliopancreatic malignancy (including biliary tract cancer or pancreatic cancer).
• Cancer-related pain: Baseline Numeric Rating Scale (NRS) pain score ≥ 4 points for over 1 week, with plans to receive celiac plexus neurolysis (CPN).
• Scheduled to receive a first-line systemic treatment regimen (e.g., PD-1/PD-L1 inhibitor monotherapy or in combination with chemotherapy/targeted therapy).
• ECOG Performance Status of 0-2 and an estimated life expectancy of ≥ 3 months.

Exclusion Criteria:

• Previous history of celiac plexus neurolysis or ablation.
• Coagulation disorders (INR > 1.5, platelet count < 50 × 10⁹/L).
• Severe cardiac, hepatic, or renal insufficiency (Child-Pugh Class C, estimated glomerular filtration rate (eGFR) < 30 mL/min, NYHA Class III-IV heart failure).
• Contraindications to celiac plexus block (e.g., local infection, anatomical variation).
• Any other condition that, in the investigator's judgment, would preclude safe participation in the study.

This study will enroll adult patients with histologically confirmed advanced biliary tract cancer or pancreatic cancer, who are experiencing moderate to severe cancer-related abdominal pain and are candidates for first-line systemic therapy combined with celiac plexus neurolysis for pain management. Key inclusion criteria involve specific pain intensity, performance status, and organ function requirements.