STUDY OF LIPID-PEROXIDATION IN PATIENTS WITH ESOPHAGEAL AND HEAD AND NECK-CARCINOMA TREATED WITH 5-FU

Background - Cardiotoxicity is a serious but relatively unknown side e ffect of 5-fluorouracil (5-FU) treatment. The underlying pathophysiolo gy of 5-FU-induced cardiotoxicity still remains poorly understood. In order to elucidate one possible mechanism behind this syndrome, we hav e studied whether 5-FU cardiotoxicity is associated with lipid peroxid ation and thereby highlights the role of free radicals in the cardioto xicity of 5-FU. Methods - Ten patients treated with 5-FU for malignanc ies in head and neck and esophagus were studied. Thiobarbituric acid-r eactive substances (TBARS), an indicator of lipid peroxidation, were m easured in plasma before treatment and on day 2 and 4 of treatment. Re sults - TBARS increased in four cases, decreased in five cases and rem ained unchanged in one case during treatment with 5-FU. Clinical featu res or ECG changes suggesting cardiac side effects, were observed in p atients with both increased and decreased TBARS (in two and one patien t respectively). Furthermore, TBARS increased in two patients who unde rwent 5-FU treatment uneventfully. Conclusions - This study does not s upport the hypothesis that lipid peroxidation could be the major limit ing mechanism underlying the 5-FU-induced cardiotoxicity.