EUS-guided photodynamic therapy with verteporfin for ablation of normal pancreatic tissue: a pilot study in a porcine model (with video).

BACKGROUND

EUS-guided photodynamic therapy (PDT) with the photosensitizing agent porfimer sodium has been shown to be effective in ablation of pancreatic tissue.

OBJECTIVE

The objective of this study was to determine the effectiveness and safety of EUS PDT with verteporfin, a photosensitizer associated with less photosensitivity.

DESIGN

Prospective investigation of 6 swine that received an IV injection of 6 mg/m2 of verteporfin before EUS.

SETTING

Hospital animal laboratory.

INTERVENTIONS

The tail of the pancreas was located with EUS and was used to guide the placement of a light catheter. The pancreatic tail was exposed to 10, 15, or 20 minutes of laser light (689 nm).

MAIN OUTCOME MEASUREMENTS

Follow-up abdominal CT, liver and renal function tests, and serum pancreatic enzymes levels were performed. Histology of the pancreas was obtained 7 days after the procedure on necropsy.

RESULTS

Localized tissue necrosis within the pancreatic tail (range 6.6-30.5 mm in diameter) was seen in all animals. The diameter of the necrotic tissue was directly related to the dose of light. No post-procedural complications were observed.

LIMITATIONS

Normal animal model (lack of malignant tissue).

CONCLUSIONS

EUS-guided PDT of porcine pancreas with verteporfin achieved localized pancreatic tissue ablation in a dose-related fashion.