N Ishida et al.
Clinical and experimental dermatology, 34(3), 385-389 (2008-12-17)
Photodynamic therapy (PDT) with 5-aminolaevulinic acid (5-ALA) is a noninvasive and effective treatment for superficial skin cancers. Etretinate, a derivate of vitamin A, with the chemical formula ethyl(2E,4E,6E,8E)-9-(4-methoxy-2,3,6-trimethylphenyl)-3,7-dimethyl-2,4,6,8-nona-tetraenoate, has been reported to have antitumour effects and to regulate the proliferation