Tirapazamine: a novel agent targeting hypoxic tumor cells.

Background: Tumor hypoxia remains one of the greatest challenges in the treatment of solid tumors, as cancer cells in these regions are resistant to killing by radiation therapy and most anticancer drugs. Tirapazamine (TPZ) is a newer class of cytotoxic drugs with selective toxicity towards hypoxic mammalian cells.

Objective: This article reviews the mechanism of action, toxicity and antitumor activity of the drug and provides insights into factors that may have contributed to the disappointing results in some of the Phase III trials.

Multiple squamous cell carcinomas of the skin after therapy with sorafenib combined with tipifarnib.

Background: Keratoacanthomas, as well as an actinic keratosis progressing to squamous cell cancer, have been reported in patients who were treated with sorafenib, a multikinase inhibitor known to suppress the actions of Raf kinase and vascular endothelial growth factor receptor.

Observations: We describe a 70-year-old white woman with metastatic renal cell carcinoma who was treated with a combination of sorafenib and tipifarnib (a farnesyltransferase inhibitor). She had no history of skin cancer.