Treatment of cutaneous T-cell lymphoma with extracorporeal photochemotherapy

Abstract

Background Cutaneous T-cell lymphoma (CTCL) and its leukemic erythrodermic form (Sézary syndrome) are malignancies of CD4+ T lymphocytes. Extracorporeal photochemotherapy (ECP) selectively affects autoreactive as well as malignant T lymphocytes. The efficacy of ECP depends strongly upon adequate serum/buffy coat levels of the photosensitizer 8-methoxypsoralen (8-MOP). The resorption of orally applied 8-MOP varies inter- and intraindividually within a broad range, meaning that adequate therapeutic drug levels cannot always be achieved. Therefore, since July 1994 we have exclusively used a liquid 8-MOP preparation which is added directly into the buffy coat fraction of the ECP circuit, resulting in constant high drug levels of approximately 190 ng/ml. Twelve CTCL-patients (six with Sézary syndrome, six with mycosis fungoides) received between six and 25 ECP treatments. Some of them had undergone previous therapy without success.Results All patients with Sézary syndrome declared a distinct reduction in intensity of pruritus. Three patients who received liquid 8-MOP extracorporeally showed a partial remission on the basis of skin scores. Of the patients receiving 8-MOP orally, two remained clinically unchanged and one showed a progression of the disease. In these cases, subtherapeutic 8-MOP plasma levels were often found. Of the six mycosis fungoides patients one achieved complete and two partial remission; another two patients showed minor response. These five patients were treated with liquid 8-MOP. One patient showed no change in skin lesions; he had received 8-MOP orally and achieved subtherapeutic photosensitizer plasma levels.Conclusion Our treatment protocols confirm the beneficial effects of ECP on CTCL at any stage, but it seems that adequate ECP efficiency is ensured only when an 8-MOP solution is applied extracorporeally.