CPM is a controversial but popular topic worldwide. Although there is insufficient evidence that CPM can significantly improve survival outcomes in breast cancer patients with general CBC risk, most female UBC patients tend to make CPM surgical decisions due to concerns about the risk of recurrence and the pursuit of breast cosmetic symmetry. Based on a Chinese patient cohort, this study analyzed and summarized CPM application trends, decision-making related factors, impact on survival outcomes such as OS and DFS, postoperative satisfaction, and impact on life quality in order to provide a reference for the future clinician and patient decisions on CPM procedures.
The results of the application trend analysis showed that CPM was first performed at our hospital in 2007, nearly 30 years later than in the 1970s in Europe and the United States. The proportion of CPM procedures as a percentage of total annual surgical procedures in UBC patients at our hospital increased significantly between 2005 and 2017 (p < 0.001), with the rate increasing from 0.40–3.02% between 2008 and 2016. This is consistent with the growth trend from 3.9–12.7% from 2002 to 2012 in the SEER database but with a lower contribution. The increase in CPM application rates, especially the rapid increase after 2012, was considered to be related to the celebrity effect of media coverage, known as the “Angelina Jolie” effect [23,24]. In contrast, the CPM application rate in the Chinese patient cohort was much lower than in the European and American populations, mainly considered to be related to the relatively conservative personality characteristics of Chinese people.
Patients with greater awareness of tumor risk have an intense fear of the disease and are willing to choose the more invasive CPM instead of BCS, with an attempt to lower the incidence of CBC and improve survival [25,26]. It has been demonstrated that CPM can reduce the risk of developing CBC by approximately 90% in females with genetic susceptibilities, such as BRCA carrier status and/or family history of breast cancer, but not in the general breast cancer population [17,27,28]. A meta-analysis that included 14 studies showed that CPM recipients had higher OS (RR = 1.09, 95% CI: 1.06, 1.11) and lower breast cancer-specific mortality (RR = 0.69, 95% CI: 0.56, 0.85) compared with non-recipients [17]. The same significant association of CPM with elevated OS and BCSS has also been proposed in two other studies with BRCA1 or BRCA2 mutation carriers [29,30]. However, several large cohort studies have found no significant improvement in BCSS and OS with CPM compared to BCS [7,31,32], and similar results were obtained in this study. There was no significant improvement in OS in the CPM group compared with the UM group in the KM survival curve analysis (p = 0.963) and CPM neither show a significant correlation with improved OS in the univariate Cox regression hazard analysis (p = 0.834), either before or after PSM. The results suggest that CPM could not lead to a better survival outcome for the Chinese female UBC patients.
The study by Bedrosian et al. [33] based on the SEER database found that CPM was associated with improved 5-year BCSS in specific patient subgroups. Risk-stratified analysis showed that this association was because of a reduction in breast cancer-specific mortality in women aged 18–49 years with stages I-II ER-negative cancer (HR = 0.68, 95% CI: 0.53, 0.88; p = 0.004). Likewise, Fayanju et al. [17] suggested that the OS benefit of CPM may be influenced by selection bias, as CPM recipients were more likely to have characteristics associated with improved survival, in terms of early tumors and adequate Medicare coverage. Our study performed a stratified subgroup analysis in the post-PSM cohort. However, no survival benefit was observed in the all age, BMI, premenopausal, family history of breast cancer and other malignancies, contralateral breast events, ER, PR, HER-2, Ki67, T-stage, and N-stage CPM subgroups. Combining subgroups of patients aged < 45 years with a BMI < 24 and no contralateral breast events, and subgroups of T stage 2/3 and N stage 1/2/3, neither showed an improvement in OS with CPM.
In previous studies, the surgical decision for CPM was influenced by BRCA1/2 mutations and a family history of malignancy, since this would raise stronger concerns about CBC [34,35]. Our study found that patients with a family history of breast cancer were preferred for CPM surgery, as well as the patients with contralateral breast lesions of BI-RADS category 3 or 4. This phenomenon is consistent with strong concerns about disease recurrence and CBC risk. In addition, patients choosing the NSM surgical procedure were more likely to undergo CPM compared to the SM, with considerations related to the greater desire for physical appearance.
The patients were followed up for postoperative satisfaction and quality of life. 69.9% of patients expressed satisfaction with their postoperative appearance, but the NSM procedure and postoperative breast reconstruction showed no higher satisfaction, probably linked to the high expectations for the cosmetic results of CPM. In terms of impact on quality of life, physical labor was most affected, likely associated with upper limb edema and a reduction in upper limb activity due to excessive concern about postoperative complications.
Despite the increased demand for CPM, there is currently insufficient evidence that CPM can improve survival in the average-risk woman, and clinical recommendations are based on the presence of a pathogenic mutation in BRCA1/2 [36]. Therefore, in patients at average risk for CBC, clinicians and patients should sufficiently discuss the decision for CPM, especially with respect to the increased risk of postoperative complications and the potential failure of postoperative breast morphology to meet expectations. Several risk prediction models, including the Manchester formula, CBCrisk, BOADICEA model, and PredictCBC, have been developed to calculate the risk of an individual developing contralateral breast cancer [37–41]. It is promising to use them to tailor clinical decision-making toward CPM or alternative preventive strategies, but careful recalibration is required before clinical application.
This study had several limitations. First, it was a retrospective study conducted in a single center, therefore selection bias may occur. Second, the sample in the CPM group was small and follow-up was limited. In addition, more detailed information such as BRCA 1/2 mutations and the utilization of preoperative neoadjuvant therapy and postoperative adjuvant therapy was lacking, which may influence the surgical options and survival outcomes of patients.