[Thyroid and lipidic dysfunction associated with bexarotene in cutaneous T-cell lymphoma].

BACKGROUND AND OBJECTIVE: Bexarotene is a synthetic selective X receptor rexinoide approved for the systemic treatment of cutaneous T-cell lymphoma. During treatment is very frequent the occurrence of hypothyroidism and severe mixed hyperlipidemia, both are reversibles and dose-dependent adverse events. Increase of triglycerides and LDL-cholesterol level (up to even higher levels have been associated with pancreatitis in some cases) is widely described (as is the case with other retinoids) but decrease in HDL-cholesterol is poored know. We review our experience with the use of bexarotene.

MATERIAL AND METHODS: We present a serie of 3 clinical report of patients treated with bexarotene in whose, in addition to these well-known adverse event, a serious lowering of HDL-cholesterol was observed.

RESULTS: The 3 patients studied had metabolic complications like central hypothyroidism and severe mixed hyperlipidemia; with special emphasis on the sharp fall (mean decrease>83%) in the HDL-cholesterol level. Cholesterol lowering medication and substitutive hormonal replacement with levotiroxine resulted in an improvement of the biochimical parameters without reaching the correct goals.

CONCLUSIONS: Bexarotene produce as predictable side effects severe mixed hyperlipidemia with marked decrease in HDL-cholesterol levels and central hypothyroidism, being the both reversible and dose-dependent. A reflection on the possible aetiological mechanisms and implications of this phenomenon are included.