Use of retinoic acids in the treatment of peripheral T-cell lymphoma: a pilot study.

Abstract

PURPOSEWe have systemically analyzed, both in vitro and in vivo, the effect of 13-cis-retinoic acids (RA) on non-Hodgkin's lymphoma (NHL).METHODSThe in vitro growth-inhibitory effect of 13-cis-RA was examined in 11 (T cell, five; B cell, six) lymphoma cell lines by a tetrazolium colorimetric assay. A pilot clinical trial with oral 13-cis-RA 1 mg/kg/d was conducted in a selected group of 18 lymphoma patients, of whom 16 had failed to respond to at least one regimen of intensive chemotherapy. The in vitro and in vivo effects of 13-cis-RA were correlated with immunophenotypes, RA-induced changes of morphology, and patterns of DNA fragmentation of the lymphoma cells.RESULTSFour of five T-lymphoma cell lines and none of six B-lymphoma cell lines were sensitive (concentration of 50% growth inhibition [IC50] < 1.5 microns) to 13-cis-RA (P = .015). In the clinical trial, five (two Ki-1, one angioinvasive type, one diffuse mixed cell, and one diffuse large cell) complete remissions and one (Ki1) partial remission ...