Patients undergo tumor biopsies and normal skin biopsies at baseline and after the first course of study treatment. Tumor tissue is examined for biological markers (e.g., epidermal growth factor receptor, ERK, Akt, p70s6k, p27, and Rb protein) by immunohistochemistry; apoptosis quantification by TUNEL assay; Ki-67 quantification and Ki-index; gene expression; and c-fos and p27 expression by reverse-transcriptase polymerase chain reaction.