Role of Photodynamic Therapy in the Management of Gastrointestinal Cancer

Abstract

Background: Surgery for cancer of the gastrointestinal tract is associated with high morbidity and mortality, especially in older patients. A significant proportion of patients cannot be cured and would be referred for palliative therapy. Others may have early cancer but are deemed unfit for surgery. Chemotherapy and external radiotherapy are suitable for only a proportion of patients. Therefore, photodynamic therapy may have a role in the management of these patients. It was the possibility of achieving selective tumour necrosis with sparing of normal tissue that made this treatment extremely appealing compared to other conventional tumour therapy. Method: The literature is reviewed (after an extensive Medline search 1975–1997) regarding the scientific basis of photodynamic therapy and the clinical experience to date with this therapy in the management of malignancies of the gastrointestinal tract. Results and Conclusions: Photodynamic therapy holds the promise of an eradication form of treatment for early cancer especially for patients deemed unfit for other treatment. It may also prove a useful supplement to other techniques in order to eliminate small residual areas of tumour left after the main bulk has been removed by other methods. The use of photodynamic therapy in the palliative management of gastrointestinal tract cancer is likely to be limited.

Photodynamic therapy for esophageal carcinoma*

“…Although the principle of PDT may be different from that used in thermic laser treatment, the overall tissue effects observed at the site of treatment are rather similar [73]. In the first 72 h after PDT edema develops [73].…”

“…In the first 72 h after PDT edema develops [73]. When the necrotic tissue finally sloughs, perforation and/or fistula formation remain a risk.…”

Endoluminal Therapy for Esophageal Disease: An Introduction

“…Endoscopic ablation methods should have a low rate of complication, such as stricture formation, bleeding, perforation, and must be well-tolerated by the patient. The endoluminal techniques that have been developed for removing BE include circumferential balloon-based radio-frequency ablation, 27-32 aminolevulinic acid and porfimer sodium photodynamic therapy, [33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] endoscopic mucosal resection and submucosal dissection, 50-52 laser ablation, 4,53-59 argon plasma coagulation, 4,53,60-71 multipolar electrocoagulation, 4,53,[72][73][74][75][76] and liquid nitrogen and carbon dioxide cryotherapy. [77][78][79] However, these devices probably differ in their method of ablation, including in treatment depth.…”

The Effects of Photodynamic Therapy in Upper-Gastrointestinal Malignant Diseases

“…Table 2 is a summary of reported cases of esophageal cancer treated by PDT showing variable complete remission rate ranging 40% to 100% for early and 91% to 100% for advanced cancer. 11 For the treatment of Barrett's esophagus, PDT can be effective in many cases. The reported rate of successful ablation of combined low grade dysplasia or Barrett's esophagus itself ranges from 82% to 100%, and successful ablation rate in high grade dysplasia or cancer was 77% to 91% (Table 3).…”