A topical formulation containing the histone deacetylase (HDAC) inhibitor with potential antineoplastic activity. Upon cutaneous administration, SHP-141 selectively binds to and inhibits HDAC, resulting in an accumulation of highly acetylated histones in the skin (dermis and epidermis), the induction of chromatin remodeling, and the selective transcription of tumor suppressor genes. These events may result in the inhibition of tumor cell division and the induction of tumor cell apoptosis. HDACs, upregulated in many tumor cell types, are a family of metalloenzymes responsible for the deacetylation of chromatin histone proteins. Topical administration of SHP-141 allows for high concentrations of this agent locally while minimizing systemic toxicity.