HSP90B1 and malignant colon neoplasm: Vitespen (formerly HSPPC-96; Oncophage; Antigenics, New York, NY, USA) is an autologous, tumour-derived HSP gp96-peptide complex that possesses potent-specific antitumour activity in melanoma and colon cancer xenograft models (Rivoltini et al, 2003), and demonstrated promising preliminary results in a phase I trial in colon cancer patients (Mazzaferro et al, 2003).