Studies of breast cancer quality of care have compared process and outcome measures to a standard across regions of United States. Rates of radiation therapy after breast conserving surgery and adjuvant therapy for locally advanced disease are lower than expected and suggest that problems may exist with the quality of care received by many women with breast cancer in the United States. Many women do not appear to be receiving indicated radiation therapy after breast conserving surgery, and in areas of the United States it appears that the percentage of women who do not receive radiation is very high. In addition, older women are less likely to receive radiation therapy after breast conserving surgery. Equally concerning, many women do not appear to be receiving adjuvant chemotherapy. Although these findings must be interpreted with caution since many of the data are from breast cancer cases diagnosed in the 1980s and collected primarily by cancer registries, they suggest that serious problems exist with the quality of care provided to women with breast cancer in the United States. To determine the quality of current practice, reliable process and outcome measures have to be applied to a national sample of newly diagnosed breast cancer patients and the results must be reported quickly.
Prostate cancer is the most commonly diagnosed non-skin cancer in men. In 1999, 179,300 cases are expected to be diagnosed, and 37,000 men are expected to die from this disease (ACS, 1999). The number of new cases diagnosed has increased in recent years as a result of adoption of prostate-specific antigen (PSA) testing (Potosky et al., 1995), largely reflecting an increase in early detection rather than a true increase in incidence.
The risk of prostate cancer increases with age, with the average age at diagnosis about 65 years and the median age about 72; it is relatively rare in men younger than 50. Five-year survival rates are very high: nearly 90 percent of men diagnosed with prostate cancer will survive at least five years (ACS, 1998).
Assessing quality of care for prostate cancer detection and treatment is especially difficult. Definitive evidence supporting the efficacy of early detection for prostate cancer awaits the results of two clinical trials. NCI's Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial is examining the efficacy of early detection of prostate and other cancers, and the Prostate Cancer Intervention Versus Observation Trial (PIVOT) is a randomized trial that is addressing the efficacy of primary treatment of early-stage prostate cancer by surgery, compared to conservative management. There is currently no professional consensus regarding whether routine screening for prostate cancer should be performed (Table 4.5). Without essential information about the efficacy of early detection, there is no standard against which to assess the quality of screening or primary treatment. The prevalence of adverse effects of treatment (complications) may provide some information about quality of care. Presently, there is some limited evidence of variation in the results of treatment from facility to facility, but very little is known about the reasons for this variation.