City from 57 of 356 in 1990 to only 2 of 190 in 1995, after instituting a template for the report that included all essential information.
These studies identify multiple steps during the diagnostic evaluation of breast cancer at which the quality of care may be affected by the quality of the procedure. Poor quality at any step could significantly impact the overall quality of care provided. Although having information on every step in the continuum of care would provide a comprehensive assessment of the quality of care, this generally is not practical. Acquiring such comprehensive data on quality would be intrusive, time-consuming, and expensive. Nevertheless, considering all of the steps necessary to a multistep process such as the diagnosis of breast cancer can be extremely valuable in trying to determine the reasons for a quality problem that has been identified (e.g., too many women diagnosed with late-stage breast cancer, a high rate of local recurrence after breast conserving surgery).
Extensive evidence is available for process-outcomes links in the treatment of breast cancer from randomized controlled trials and meta-analyses of these trials. Surgery has been the primary treatment for localized breast cancer since Halsted popularized the radical mastectomy in 1894 (Halsted, 1894). More recently, randomized controlled trials have demonstrated equivalent survival with a modified radical mastectomy or with breast conserving surgery followed by radiation therapy (Fisher et al., 1985; Sarrazin et al., 1984; Veronesi et al., 1981). In addition, having a choice of surgery appears important to a woman's subsequent quality of life; studies have not demonstrated any difference in overall quality of life between women who received breast conserving surgery and those treated with modified radical mastectomy as long as they were offered a choice of primary therapy (Ganz et al., 1992a; Kiebert et al., 1991). The most recent National Institutes of Health Consensus Conference statement for the treatment of early-stage breast cancer specifies breast conserving surgery as the preferred mode of therapy for the majority of women with Stage I and II breast cancer (NIH, 1990). Compared to modified radical mastectomy, breast conserving surgery has fewer short-term complications, but may require a similar length of convalescence because of the recommended six weeks of postsurgery radiation therapy. It is not a less costly treatment.
Strong process-outcomes links also exist for treating women with local or regional breast cancer with chemotherapy or hormone therapy or both in addition to surgery and radiation. Systemic treatment with chemotherapy or hormone therapy after all identifiable cancer has been removed surgically is termed adjuvant therapy. The goal of adjuvant therapy is to decrease future recurrences and thereby improve survival. However, the issue of adjuvant therapy in breast cancer raises another important consideration: When, despite strong evidence in the literature for a process-outcomes link, is the impact on outcome so small that the process should not be considered requisite for quality care? Adjuvant systemic therapy with either chemotherapy or hormone therapy has been demonstrated in randomized controlled clinical trials to improve survival in all women with breast cancer, although the benefit in women with very favorable prognoses is extremely small (EBCT, 1992, 1998). In addition, a small but significant improvement in both overall and disease-free survival is obtained from combined treatment with chemotherapy and tamoxifen (hormone therapy), compared with tamoxifen alone, in women with estrogen receptor-