Photosensitization with hematoporphyrin derivative compared to 5-aminolaevulinic acid for photodynamic therapy of esophageal carcinoma

Background. Hematoporphyrin derivatives (HpD) as sensitizers for photodynam ic therapy (PDT) in advanced esophageal cancer carry the risk of prolonged photosensitivity of the skin. New sensitizers such as 5-aminolae-vulinic ac id (ALA) with low rates of skin phototoxicity appear to be promising altern atives. The aim of this study was to evaluate the efficacy of ALA compared with HpD for PDT in advanced esophageal carcinoma regarding phototoxicity o f the skin, reduction of dysphagia, tumor stenosis and length, and Karnovsk y performance status. Methods. After diagnostic workup, photosensitization was done in 22 patient s with ALA (60 mg/kg body weight, oral, 6 to 8 hours before PDT) and in 27 patients with a hematoporphyrin derivative (2 mg/kg body weight, intravenou sly, 48 hours before PDT). The light dose was calculated as 300 J/cm fiber tip. Light at 630 run was applied using a pumped dye laser. In both groups, additional hyperbaric oxygenation was applied at a level of 2 absolute atm ospheric pressure. Results. Improvement regarding dysphagia, stenosis diameter, and tumor leng th could be obtained in both treatment arms with a significant difference i n favor of the HpD group (p = 0.02, p = 0.0000; and p = 0.000014, respectiv ely). A questionnaire of patients in the Hpl) group confirmed that the abil ity of swallowing a meal was superior compared with the discomfort from lim itation to sun exposure. No sunburn or other major treatment-related compli cation occurred in both treatment arms. Conclusions. Despite the limitations of a nonrandomized study, photosensitz ation with Hpl) seems to be more effective in PDT of advanced esophageal ca rcinoma compared with ALA. (C) 2001 by The Society of Thoracic Surgeons.