High dose chemotherapy--results of American studies

The role of high dose chemotherapy in the treatment of solid tumors is a subject of robust debate. Opinions range from the adoption of high dose chemotherapy with hematopoietic progenitor support as standard therapy for a number of solid tumors to the view that the application of such expensive and potentially toxic therapy is always experimental and should be the subject of clinical trials to define the role, if any. In germ cell tumors, the role of high dose chemotherapy is somewhat less contentious. In the US, high dose carboplatin and etoposide-based chemotherapy is routinely accepted as standard therapy for those patients failing prior standard dose regimens. There is increasing acceptance of the role of similar high dose therapy as a component of aggressive second line therapy and some initial acceptance of a potential role in primary treatment of poor risk disease. Formal study of these questions has been hampered by the rarity of the illness, the success of standard therapy and the smaller number of patients presenting with far advanced disease. This review will highlight the scientific underpinning of the role of high dose chemotherapy in multiply relapsed patients, as a component of initial salvage therapy and, finally as an attempt to improve outcome in patients with poor risk presenting features. As well, an attempt will be made to highlight where new prognostic information has influenced the design of current studies.