PHOTODYNAMIC THERAPY OF EARLY SQUAMOUS-CELL CARCINOMAS OF THE ESOPHAGUS - A REVIEW OF 31 CASES

Background and Study Aims: Patients with cancers of the head and neck have a strong tendency to develop early synchronous and metachronous c arcinomas of the esophagus, In many of these patients, whose general c ondition is poor as a result of alcohol and tobacco abuse, the second primary cancers require minimally invasive treatment. The aims of this study were to evaluate the efficacy of photodynamic therapy for the t reatment of early esophageal carcinomas and to compare the results obt ained with three different photosensitizers (hematoporphyrin derivativ e), porfimer sodium (Photofrin II), and meta-(tetrahydroxyphenyl)chlor in (m-THPC). Patients and Methods: Thirty-one early squamous cell carc inomas (T-is or T-1a) of the esophagus were treated by photodynamic th erapy in 24 patients, Nine tumors were treated with hematoporphyrin de rivative, eight with Photofrin II and 14 with m-THPC. Results: The ear ly cancers were cured in 84% of patients after a mean Follow-up period of 2 years. Because the number of cases included in each group was sm all, the differences in recurrence rates for the different photosensit izers could not be evaluated statistically, but m-THPC was more photot oxic, induced a shorter period of photosensitization of the skin, and had better selectivity than either of the other photosensitizers. Ther e were four major complications: two stenoses and hr-oo esophagotrache al fistulas. Conclusions: Photodynamic therapy eradicates early squamo us cell carcinomas (T-is and T-1a) of the esophagus efficiently. Trans mural necroses leading to fistulas fan be avoided bg using a low-penet rating wavelength of laser light (green light at 514.5 m instead of I ed light at 630 or 652 nm), Stenoses always result from circumferentia l irradiation of the esophageal wall, and this can be avoided by using a 180 degrees or 240 degrees windowed cylindrical light distributor.