Collateral damage from targeted therapy

• Published in: Pathology 2015, Vol.47, p.S13-S13
• Main Authors: Rankin, Wayne, Coates, Penelope
• Format: Article
• Language: English
• ISSN: 0031-3025; 1465-3931
• DOI: 10.1097/01.PAT.0000461368.44897.27

The introduction of biological therapies using monoclonal antibodies and small-molecule inhibitors targeted against cell surface receptors and associated signalling molecules has led to marked changes in the management of inflammatory and malignant disease. Theoretically, the use of such agents in oncology provide therapeutic benefit without the systemic toxicities associated with cytotoxic chemotherapies. In practice, however, many of these agents have marked toxicities, some able to be predicted from the mechanism of action, and others that have become apparent after careful post-marketing surveillance. Ipilimumab is one such agent and is currently used for immunotherapy in patients with late-stage melanoma. It is a monoclonal antibody that binds to cytotoxic T lymphocyte-associated antigen 4, resulting in T-cell activation and proliferation, and thus enhanced but unregulated cell-mediated immune activity. Here we illustrate the potential complications of such apparently directed therapy, via the case of a 63-year-old man with metastatic melanoma being treated with ipilimumab, and highlight the role of the Chemical Pathology laboratory in the identification and management of these complications.