bers of procedures used in cancer therapy and the aging of the population contribute to the overall costs of cancer treatment (Journal of the National Cancer Institute, 1998). While improved survival has resulted for individuals diagnosed with early-stage cancers, eventually succumbing to the disease continues to be a likely outcome for many.

As the scope of clinical trials broadens to include individuals with late-stage disease, improved survival and tumor response remain the primary end points. Clearly, these end points are insufficient for this population. Researchers and clinicians are beginning to identify as end points the distressing symptoms of advanced cancer. The National Cancer Institute provides a comprehensive list of the six different categories of clinical trials— treatment, prevention, diagnostic, genetic, screening, and supportive care —on its Web site (http://cancernet.nci.nih.gov/cgi-bin/srchcgi.exe). A search of the supportive care category revealed 90 ongoing Phase II and III clinical trials. The primary end points were toxicity profiles, side effects, response rate, maximum tolerated dose, dose-limiting toxicities, event-free survival, and pharmacokinetic profile. Only a few studies aimed for other end points. Among the 38 Phase II trials, 7 explored quality of life (QOL) and/or symptom relief as primary or secondary end points in the advanced cancer population. Among the 52 Phase III trials, 13 specifically addressed QOL or symptom management or relief (pain, diarrhea, sleep disturbances, toxicities), in addition to tumor response and survival time.

Irrespective of the physiological or behavioral end point, financial considerations are rarely primary or secondary end points in clinical trials. None of the NCI supportive care clinical trials listed cost as an end point. A MEDLINE search of clinical trials about pain published over the past 10 years in the advanced cancer population yielded 265 trials. However, when cost, cost-effectiveness, health care costs, or economics was entered as a search term, only five remained. An even smaller proportion of advanced lung cancer trials (7 out of 725) listed these financing terms. In both types of studies, financial considerations were most often merely cursory commentaries, not study end points. Given the disturbingly high number of distressing symptoms afflicting the majority of the terminally ill cancer population, much more attention must be given to cost-effective symptom management modalities.

Generalizability

The generalizability of findings from advanced cancer clinical trials is also problematic, particularly with respect to age. Cancer has often been labeled a disease of aging, with estimations of a 10-fold increased likelihood of being diagnosed with cancer for those over 65 than for those under 65. Yet the median age of participants with advanced cancer in clinical



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