The majority of women diagnosed with breast cancer are clinically eligible for two surgical treatment approaches: mastectomy or lumpectomy (also referred to as breast conserving surgery [BCS]). It is well-established that mastectomy and BCS accompanied by radiation therapy confer an equivalent rate of survival for patients without metastatic disease (National Institutes of Health 1990; Fisher et al. 1999). Thus, the surgical treatment of breast cancer is a good example of what has been described as preference-sensitive care, or care situations in which there are two or more treatment options that are medically justified (Wennberg 2002a). As the label implies, when multiple treatment paths are available and clinically appropriate, the decision process should incorporate and be sensitive to patient preferences regarding the various treatment options (Wennberg 2000b).

Several studies have suggested that shared medical decision making between patients and providers can improve patient satisfaction and even improve some clinical outcomes (Kaplan, Greenfield, and Ware 1989; Laine and Davidoff 1996; Deadman et al. 2001). Many clinicians, researchers, and advocates have argued that breast cancer surgery--as a type of preference-sensitive care--provides an excellent opportunity for shared decision making between patient and provider (Guadagnoli and Ward 1998; Gafni, Charles, and Whelan 1998; Fallowfield et al. 1990). A number of interventions promoting shared-decision models in breast cancer surgical treatment have been designed and evaluated (Whelan et al. 1999; Sepucha et al. 2000). In addition, 20 states have passed laws mandating that patients be informed of both mastectomy and BCS as options (Nayfield et al. 1994; Montini 1997).

An explicit assumption in much of this program and policy development is that mastectomy is "over-used" (National Cancer Policy Board 1999; Morris et al. 2000). The observed geographic and sociodemographic variation in rates of mastectomy versus BCS has not only been labeled as a problem in terms of "over-treatment" but also as an explicit indication of a lack of decision involvement or control among breast cancer patients (Lazovich et al. 1991; Wennberg 2002b). As such, increasing the use of BCS is viewed as a positive goal; and the promotion of patient choice and shared decision making is viewed as the primary means by which this goal can be achieved.

Despite a tacit assumption that increasing patient choice will increase the use of BCS, there is some evidence to suggest that increasing patient involvement is not a simplistic goal, and will not necessarily decrease mastectomy rates. The results of several studies emphasize that not all patients are comfortable with or want to participate in medical decision making, even in the case of preference-sensitive care (Pierce 1993; Schneider 1995; Collins, Kerrigan, and Anglade 1999; Robinson and Thompsom 2001). In addition, Keating et al. (2002) found in a sample of early-stage breast cancer patients that only one-half of the patients participated in the decision making process to the extent that they desired, but that those with more active participation had higher rates of mastectomy. Patients' concerns about cancer recurrence, radiation therapy, the personal costs/benefits of breast reconstruction, and other salient aspects of surgical treatment play important roles in the decision process, even in the face of a strong recommendation for BCS from a surgeon (Nold et al. 2000; Katz, Lantz, and Zemencuk 2001; Keating et al. 2002; Katz et al. 2004).

The primary indicator of progress and quality of breast cancer care should not be the rate of BCS alone (Lantz, Zemencuk, and Katz 2002). Rather, a broader context needs to be considered, including important dimensions of patient satisfaction related to both the outcomes and process of care. The purpose of the research presented here was to investigate patterns in and determinants of satisfaction with surgical treatment and the decision making process in a large, population-based sample of women recently diagnosed with breast cancer. Given that breast cancer surgery is a type of "preference-sensitive care," there is no ideal or target rate of BCS (Ganz 1992). Therefore, rather than view the prevalence of BCS as the primary indicator of quality of care, we investigated patient satisfaction along three dimensions: (a) satisfaction with the type of surgery received; (b) satisfaction with the process by which the surgery decision was made; and (c) feelings of ambivalence or regret regarding the type of surgery received. The main objectives were to describe the prevalence of low satisfaction and decision ambivalence/ regret in a population of breast cancer patients, and to identify patient sociodemographic and clinical characteristics--including the type of surgery received--associated with satisfaction and decision appraisal.