This is a companion piece to yesterday's posting about increasing number of women opting for mastectomies vs wide excisions. A recent study by Jones and her colleagues at Ohio State University found growing numbers of women with early stage breast cancer opting for prophylactic bilateral mastectomies. Here is a quote from that article:
ORIGINAL ARTICLE - BREAST ONCOLOGY
Contralateral Prophylactic Mastectomy for Unilateral Breast
Cancer: An Increasing Trend at a Single Institution
Natalie B. Jones, MD, John Wilson, PhD, Linda Kotur, BS, CTR, Julie Stephens, MS, William B. Farrar, MD, and Doreen M. Agnese, MD Department of Surgery, Division of Surgical Oncology, The Ohio State University, Columbus, OH; James Cancer Hospital, CHRI Administration, The Ohio State University, Columbus, OH; Outcomes Management, The Ohio State University, Columbus, OH; Center for Biostatistics, The Ohio State University, Columbus, OH
Background. An increasing trend in the use of contralateral prophylactic mastectomy (CPM) for the treatment of unilateral breast cancer has been observed nationally. The purpose of this study was to confirm this trend and to identify differences between the groups that chose unilateral mastectomy alone or with CPM.
Methods. A prospectively maintained breast cancer database was retrospectively reviewed. Age, histologic grade, stage, education, family history, tumor receptor status, and use of immediate reconstruction were evaluated. Statistical analysis was performed by Fisher's exact test, v 2 test, and Student's t-test.
Results. Between 1998 and 2007, a total of 1639 women who selected UM and 201 who had UM and CPM for unilateral breast cancer were identified. An increasing trend in CPM was observed (6.5% in 1999 vs. 16.1% in 2007). The CPM group was significantly younger (mean age 47.8 vs. 55.1 years, P\.001). No difference in histologic grade was noted between the two groups; however, an increasing trend toward CPM was observed with lower-stage disease. Women with a higher educational level were more likely to have CPM (P\.001). Women with a family history of cancer were also more likely to have CPM (57% vs. 41%, P\.001). Use of reconstruction was similar between the groups (6.0% for CPM vs. 6.7% for UM, P = NS).
Conclusions. Our experience parallels the national trend of increasing use of CPM in women diagnosed with unilateral breast cancer. Women who chose to have CPM were younger, more highly educated, and more likely to have a family history of cancer. Breast-conservation therapy has been increasing since 1990, when the National Institutes of Health Consensus Development Conference Statement was released advising breast conservation. The overall pool of women having unilateral mastectomy (UM) has therefore shrunk; however, within this smaller group, there seems to be a rising trend toward the use of contralateral prophylactic mastectomy (CPM) for the treatment of unilateral breast cancer.
CPM for stage I to III unilateral breast cancer increased 150% from 1998 to 2003 in the United States. That translates to approximately 10,000 patients with unilateral breast cancer undergoing CPM in the United States each year. Patients with unilateral breast cancer are clearly at increased risk for the development of contralateral breast cancer. In the average breast cancer patient, this risk is approximately .5% to 1% per year, and may be even higher in certain populations, such as women with hereditary breast and ovarian cancer syndrome. Women with unilateral breast cancer are generally closely followed with regular clinical breast examinations, mammography, and, in some instances, ultrasound and magnetic resonance imaging to detect additional disease. In addition, women with hormone-responsive tumors are treated with endocrine therapy (tamoxifen or an aromatase inhibitor), which greatly reduces the incidence of contralateral breast cancer. Although contralateral breast cancers can occur, these second primary tumors tend to be detected at an earlier stage than the first breast cancer and are unlikely to greatly affect survival. The data in support of CPM, although conflicted, suggest that it does not improve survival.
Herrinton et al. reported that CPM decreased overall breast cancer mortality rate and overall mortality. In contrast, a Cochrane review of eight studies found that CPM decreased the incidence of contralateral breast cancer, but was not associated with survival improvement. The decision< to undergo CPM is certainly multifactorial and complex, and it is important to evaluate this trend and overall process. What are the factors leading to this decision when survival may not be a factor? Recent data suggest that the variables associated with higher rates of CPM include young patient age, non-Hispanic white race, lobular histology, and previous cancer diagnosis. Regardless of the cause, a recent review of the Surveillance, Epidemiology, and End Results (SEER) Program database showed that the use of CPM in the United States has more than doubled within the recent past. The nature of the SEER database makes it a resource of limited value. It does not allow for detailed patient and tumor information because many important details are not available. This study was undertaken to determine whether or not this trend in CPM use occurred at our institution and to study the variables that influence a woman's decision to select CPM versus UM.