Photodynamic Therapy Combined With a Self-expandable Radioactive Particle-loaded Biliary Stent for Unresectable Extrahepatic Cholangiocarcinoma (Photodynamic T)

Background: Extrahepatic cholangiocarcinoma is often diagnosed at an advanced stage, precluding curative surgery. Traditional treatments like chemotherapy and radiotherapy have limited efficacy. Photodynamic therapy (PDT) is a minimally invasive local treatment that can destroy tumor cells, but its effective depth is limited (4-6 mm), which may lead to rapid tumor progression or recurrent biliary obstruction. The self-expandable radioactive particle-loaded biliary stent not only provides mechanical biliary drainage but also delivers continuous local brachytherapy (Iodine-125) to inhibit tumor growth. This study proposes that combining PDT with this radioactive stent may provide synergistic effects, prolonging stent patency and improving survival for patients with unresectable extrahepatic cholangiocarcinoma.

Study Design: Prospective, single-arm, interventional clinical study.

Procedures:

PTCD will be performed first to relieve jaundice and improve liver function.

A skin test for photosensitizer allergy will be conducted. If negative, Hematoporphyrin (3mg/kg) will be administered intravenously.

48-72 hours later, DSA-guided biliary tumor biopsy and PDT will be performed (1-2 sessions depending on tolerance).

A self-expandable biliary stent loaded with Iodine-125 particles will be implanted into the stricture after balloon dilation. The drainage tube will be kept for 1-2 weeks post-operation and then removed.

Follow-up: Patients will be followed up every 3-4 weeks initially, and then every 3 months after stabilization (up to 2 years) to monitor tumor response, survival, stent patency, liver function, and adverse events.