Optimization of light dosimetry for photodynamic therapy of Barrett's esophagus

Masoud Panjehpour; Mary N. Phan; Bergein F. Overholt; John M. Haydek

doi:10.1117/12.528017

14 June 2004 Optimization of light dosimetry for photodynamic therapy of Barrett's esophagus

Masoud Panjehpour, Mary N. Phan, Bergein F. Overholt, John M. Haydek

Proceedings Volume 5315, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XIII; (2004) https://doi.org/10.1117/12.528017
Event: Biomedical Optics 2004, 2004, San Jose, CA, United States

Abstract

Background and Objective: Photodynamic therapy (PDT) may be used for ablation of high grade dysplasia and/or early cancer (HGD/T1) in Barrett's esophagus. A complication of PDT is esophageal stricture. The objective of this study was to find the lowest light dose to potentially reduce the incidence of strictures while effectively ablating HGD/T1. Materials and Methods: Patients (n=113) with HGD/T1 received an intravenous injection of porfimer sodium (2 mg/kg). Three days later, laser light (630 nm) was delivered using a cylindrical diffuser inserted in a 20 mm.diameter PDT balloon. Patients were treated at light doses of 115 J/cm, 105 J/cm, 95 J/cm and 85 J/cm. The efficacy was determined by four quadrant biopsies of the treated area three months after PDT. The formation of stricture was determined by the incidence of dysphagia and the need for esophageal dilation. Strictures were considered mild if they required less than 6 dilations, and severe if 6 or more dilations were required. Efficacy and incidence of strictures were tabulated as a function of light dose. Results: Using 115 J/cm, there were 17% of patients with residual HGD/T1 after one treatment. However, when the light doses of 105 J/cm, 95 J/cm and 85 J/cm were used, the residual HGD/T1 after one PDT session was increased to 33%, 30%, and 32% respectively. The overall incidence of strictures (mild and severe) was not correlated to the light dose. However, the incidence of severe strictures was directly proportional to the light dose. Using the light dose of 115 J/cm, 15.3% of patients developed severe strictures compared to about 5% in the groups of patients who received the lower light doses. Conclusions: Decreasing the light dose below 115 J/cm doubled the rate of residual HGD/T1 after one treatment while reducing the incidence of severe strictures to one-third of cases from 115 J/cm. The results may be used to evaluate the risks and benefits of different light doses.

Citation Download Citation

Masoud Panjehpour, Mary N. Phan, Bergein F. Overholt, and John M. Haydek "Optimization of light dosimetry for photodynamic therapy of Barrett's esophagus", Proc. SPIE 5315, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XIII, (14 June 2004); https://doi.org/10.1117/12.528017

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available