Outcomes of cancer treatment for technology assessment and cancer treatment guidelines

In 1993, the Health Services Research Committee of the American Society of Clinical Oncology (ASCO) charged an Outcomes Working Group with defining the outcomes of adult and pediatric cancer treatment to be used for technology assessment and development of cancer treatment guidelines. The Working Group defined by consensus outcomes for technology assessment and guideline development, focusing on cancer treatments. The Working Group considered a variety of perspectives on outcomes, including those of patients, physicians, clinical investigators, ASCO, and policy makers. Because ASCO's guidelines will define what constitutes the best treatment and not whether that treatment should be paid for, the Working Group gave higher priority to the clinical and clinical research perspectives than to the health policy perspective. Survival is the most important outcome of cancer treatment. An improvement in at least disease-free survival is a prerequisite for recommending adjuvant therapy. In the case of metastatic cancer, treatment can be recommended even without an improvement in survival, if it improves quality of life. Quality of life includes global quality of life, as well as its physical, psychologic, and social dimensions. To be an outcome of cancer treatment, quality-of-life measures must be sensitive to clinically meaningful changes produced by treatment; evaluations must control far placebo effects and determinants of quality of life not related to cancer or its treatment. Toxicity, both short and long term, is vitally important, with the latter being particularly critical in children. The value of cancer outcomes like tumor response (eg, complete or partial response) and biomarkers (eg, CA-125) for technology assessment and guideline development depends on their ability to predict patient outcomes (survival and quality of life) or to influence decisions about treatment. Complete response is an important outcome when it predicts survival. Progression is important because it signals the need to change or stop treatment. Cost-effectiveness is an especially important outcome to consider when the benefits of treatment are modest or the costs are high. Patient outcomes (eg, survival and quality of life) should receive higher priority than cancer outcomes (eg, response rate), but both types of outcomes are important in technology assessment and guideline development. Multiple outcomes should be considered because no single outcome adequately describes the results of cancer treatment. In general, there is no minimum benefit above which treatments are justified; rather, benefits should be balanced against toxicity and cost.