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

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.

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.

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.

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.