New guidelines to evaluate the response to treatment in solid tumors. European Organization for Research and Treatment of Cancer, National Cancer Institute of the United States, National Cancer Institute of Canada

Therapeutic studies

This article discusses the problems in basic design, conduct, and interpretation associated with phases I, II, and III of the cancer clinical trials and explains the various statistical solutions to these problems. The fundamental problem common to all three trials is achieving a correct and precise answer to the question posed to inform future testing and treatment while protecting trial patients from receiving treatment that has demonstrated excessive toxicity or lack of clinical efficacy. This shared problem gives rise to statistical designs with basic similarities across the three trial types.

Clinical imaging of cancer metastasis

Tumour imaging is an essential part of the practice of oncology, with a crucial role in screening programmes and in diagnosis and staging of established disease. Furthermore, the assessment of tumour size by imaging, usually with computer tomography (CT) scanning, is a key component in determining the tumour response to therapy both in clinical trials and in daily oncology practice. Techniques such as CT, ultrasound (US) and magnetic resonance imaging (MRI) provide high resolution anatomical images with detailed structural information. However, these imaging modalities yield limited functional information on the tumour tissues and often cannot distinguish residual disease from non-viable or necrotic tumour masses, nor can they detect minimal residual disease. In contrast, radiopharmaceutical imaging and, in particular, positron emission tomography (PET) can give some functional information about the underlying tissues. The possibility of refining these techniques and also the emergence of newer imaging modalities that can detect changes in cancers at the physiological, cellular or molecular levels, gives rise to the notion that these methods will have implications for drug development strategies and also future clinical management. In this review, we briefly discuss the current role of imaging in clinical practice, describe some of the advances in imaging modalities currently undergoing evaluation, and speculate on the future role of these techniques in developmental therapeutics programmes.

Clinical studies in the development of new anticancer agents exhibiting growth inhibition in models: facing the challenge of a proper study design

Various new specifically targeted anticancer agents such as matrixmetalloproteinase inhibitors, angiogenesis inhibitors, farnesyl transferase inhibitors, and tyrosine kinase inhibitors have been developed in recent years. These agents exert antitumor activity through specific target inhibition, and preclinical studies showed dose-dependent tumor growth inhibition and only sporadic tumor regressions. Toxicity of these new agents was often strikingly mild or did not occur at all. Clinical studies are now being performed. Because these new agents might have a different toxicity profile and exert their antitumor activity in a way that is completely different from that of cytotoxic agents, the design of clinical studies will have to be adapted in several ways, and new endpoints for phase I, II, and III studies must be defined.