Contralateral Risk-Reducing Mastectomy in Breast Cancer Patients Who Undergo Multigene Panel Testing

Incorporating Value-Based Decisions in Breast Cancer Treatment Algorithms

Given the excellent prognosis and availability of evidence-based treatment, patients with early-stage breast cancer are at risk of overtreatment. In this review, we summarize key opportunities to incorporate value-based decisions to optimize the delivery of high-value treatment across the breast cancer care continuum.

Low temperature plasma suppresses proliferation, invasion, migration and survival of SK-BR-3 breast cancer cells

BACKGROUND

Low temperature plasma (LTP) is a developing field in recent years to play important roles of sterilization, material modification and wound healing. Breast cancer is a common gynecological malignant tumor. Recent studies have shown that LTP is a promising selective anti-cancer treatment. The effect of LTP on breast cancer is still unclear. In this study, We treated breast cancer cell lines with low temperature plasma for different periods of time and analyzed the relevant differences.

METHODS AND RESULTS

SK-BR-3 cell nutrient solution was firstly treated by ACP for 0, 10, 20, 40, 80 and 120 s, which was next used to cultivateSK-BR-3cells for overnight.we found that LTP was able to suppress cell vitality, proliferation, invasion and migration of SK-BR-3 cells. Also, SK-BR-3 apoptosis was induced by LTP in a time-dependent manner.

CONCLUSION

These evidences suggest the negative effect of LTP on malignant development of SK-BR-3 cells, and LTP has the potential clinical application for breast cancer treatment.

Contralateral Prophylactic Mastectomy among Women with Pathogenic Variants in BRCA1/2: Overall Survival, Racial, and Ethnic Differences

Background

Patients with unilateral breast cancer carrying pathogenic variants in BRCA1/2 have the option to undergo contralateral prophylactic mastectomy (CPM). However, differences in CPM use and survival outcomes following CPM are poorly understood in this high-risk population, in part due to a lack of data from contemporary clinical cohorts. The objective of this study was to evaluate post-CPM overall survival (OS) and related racial/ethnic differences in a contemporary clinical cohort.

Methods

We retrospectively reviewed the medical records of women with a personal history of unilateral breast cancer carrying pathogenic variants in BRCA1/2 who were diagnosed between 1996 and 2012. Genetic test results, self-reported demographic characteristics, and clinical factors were abstracted from electronic medical records.

Results

Of 144 BRCA-positive patients, the majority were White (79.2%, n = 114). Overall, 56.1% (n = 81) of all BRCA1/2 carriers chose to undergo CPM, with no racial/ethnic difference in CPM election (p = 0.78). Of 81 patients who underwent CPM, there is strong evidence of a difference in survival between the racial/ethnic groups, with White patients having the highest OS compared to non-White patients (p = 0.001). Of the 63 patients who did not undergo CPM, there is no racial/ethnic difference in overall survival (p = 0.61). In multivariable cox regression, adjusted for demographic and clinical characteristics, OS was significantly lower among non-Whites than in Whites (HR = 0.39, p = 0.04).

Conclusions

Evaluation of a contemporary clinical cohort of BRCA-positive women with unilateral breast cancer showed no racial/ethnic difference in CPM use, but there was a significant difference in post-CPM overall survival.

Germline Genetic Testing in Breast Cancer: Systemic Therapy Implications

PURPOSE OF REVIEW

In this article, we discuss recent advances in germline genetic testing for patients with breast cancer and highlight current limitations and impacts on clinical care. We also provide an update on the therapeutic implications of having a germline mutation, including targeted systemic therapy options for treating early and metastatic breast cancer.

RECENT FINDINGS

Approximately 5 to 10% of women diagnosed with breast cancer have a pathogenic variant in a hereditary cancer susceptibility gene, which has significant implications for managing these patients. Previously, testing was done mainly to inform screening and risk-reduction treatment; however, more recently, germline genetic results have significant systemic therapy implications that can meaningfully improve outcomes in breast cancer patients, especially with oral poly-ADP-ribose polymerase (PARP) inhibitors. These systemic therapy advances implore a shift in paradigm for whom to test moving forward and how to modify the existing testing models to meet the increasing demand for germline testing, which is expected to grow exponentially.

Risk‐reducing mastectomy decisions among women with mutations in high‐ and moderate‐ penetrance breast cancer susceptibility genes

Background

Women harboring mutations in breast cancer susceptibility genes are at increased lifetime risk of developing breast cancer and are faced with decisions about risk management, including whether to undergo high‐risk screening or risk‐reducing mastectomy (RRM). National guidelines recommend BRCA1 or BRCA2 mutation carriers consider RRM, but that carriers of moderate penetrance mutations (e.g., ATM or CHEK2) should be managed based on family history. We aimed to investigate determinants of decision for RRM, and hypothesized that mutation status, age, family history, partner status, and breast cancer would impact RRM decision making.

Methods

We performed a retrospective study assessing RRM decisions for 279 women.

Results

Women with BRCA and moderate penetrance gene mutations, a personal history of breast cancer, or a first degree relative with a history of breast cancer were more likely to undergo RRM. Breast cancer status and age showed an interaction effect such that women with breast cancer were less likely to undergo RRM with increasing age.

Conclusion

Although national guidelines do not recommend RRM for moderate penetrance carriers, the rates of RRM for this population approached those for BRCA mutation carriers. Further insights are needed to better support RRM decision‐making in this population.

Influence of germline test results on surgical decision making in women with invasive breast cancer

BACKGROUND

While therapeutic mastectomy with contralateral prophylactic mastectomy (TM+CPM) and/or bilateral salpingo-oophorectomy (BSO) are recommended for women with pathogenic variants (PV) in some cancer predisposition genes, evidence for the utility of these surgeries for women with PV in other genes currently is insufficient. In conjunction, current guidelines recommend that clinical management should not be influenced by a return of a variant of uncertain significance (VUS). Return of germline test results may, however, influence surgical decision making regardless of current guidelines. We thus evaluated surgical choices amongst a cohort of women with invasive breast cancer who underwent clinical genetic testing.

METHODS

Germline test results and all surgical procedures were extracted for women who had unilateral invasive breast cancer and had clinical testing before definitive surgery (n = 591). Results were classified as pathogenic/likely pathogenic (PV, 17.1%), VUS (19.5%) or benign/likely benign (63.4%). Data were analyzed using chi-square tests with p<0.05 defining significance.

RESULTS

Rates of TM+CPM and BSO were not significantly different for women with VUS compared to those with benign findings. Rates of TM+CPM were significantly higher for women with PV in BRCA1 and BRCA2, PALB2, PTEN and TP53, as well in genes with insufficient data to recommend risk-reducing mastectomy. Rates of BSO were significantly higher in women with PV in BRCA1 and BRCA2, PALB2, PTEN and TP53 and BRIP1, RAD51C and RAD51D compared to those with benign findings.

CONCLUSION

Overall, surgical choices for women with a VUS were more similar to those from women with benign variants than to those with PV, however, in the group with PV in genes for which insufficient evidence exists for the benefit of risk-reducing mastectomy, rates of TM+CPM were high. Thus, while the management of women with VUS is in agreement with ACMG guidelines, patients with mutations in other cancer genes demonstrate a preference for more aggressive breast surgeries.

Clinical management among individuals with variant of uncertain significance in hereditary cancer: A systematic review and meta-analysis

Improper medical use of variant of uncertain significance (VUS) remains a concern in hereditary cancer genetic testing. The goal of this study was to assess the association between pathogenic and likely pathogenic (P/LP), VUS, and benign and likely benign (B/LB) genetic test results and cancer-related surgical and screening management. Systematic searches of Medline, Embase, EBSCO CINAHL Plus, and PsycINFO were conducted from 1946 to August 26, 2020. Eligible studies included individuals with cancer genetic test result and surgical or screening management outcomes. We reviewed 885 abstracts and 22 studies that reported relevant surgical and screening outcomes were included. Meta-analysis revealed significantly higher surgical rates among individuals with P/LP than among those with VUS for therapeutic mastectomy with contralateral prophylactic mastectomy (OR = 7.35, 95% CI, 4.14-13.64), prophylactic mastectomy (OR = 3.05, 95% CI, 1.5-6.19), and oophorectomy (OR = 6.46, 95% CI, 3.64-11.44). There were no significant differences in therapeutic mastectomy, or breast conservation or lumpectomy rates between individuals with P/LP and VUS, or in any outcomes between patients with VUS and B/LB. Studies evaluating screening outcomes were limited, and results were conflicting. Comprehensive analysis do not indicate that a significant number of individuals with VUS results undergo inappropriate clinical management.

Longitudinal Risk Management for Patients with Increased Risk for Breast Cancer

INTRODUCTION

This study aims to characterize longitudinal care management and evaluate the relationship between various patient factors and the likelihood of choosing risk-reducing behaviors in women with increased risk of developing breast cancer.

METHODS

A retrospective study was conducted to evaluate all adult female patients who had at least one clinic visit with a surgical provider for discussion of breast cancer risk assessment between January, 2017 to July, 2020 at an academic center. Patients with prior history of breast cancer were excluded. Patient details and strategies pursued at clinic visits were recorded. A time-to-event analysis was performed, and hazard ratios were determined to characterize associations between patient characteristics and time to pursuing risk-reducing care management.

RESULTS

There were 283 participants with at least one follow-up visit and 48 (17.0%) ultimately changed their initial strategy to either chemoprevention or prophylactic mastectomy. Patients with gene mutations were 6 times more likely to engage in risk-reducing management compared to those without (hazard ratio (HR) 5.99, P < 0.001). Those with histories of high-risk proliferative changes (HR 7.62, P < 0.001) and hysterectomy (HR 2.99, P = 0.019) were also more likely to engage in risk-reducing management. Age, race, and increased predicted risk of developing breast cancer (estimated by various calculators) were not associated with increased likelihood of engaging in risk-reducing strategies.

CONCLUSION

Known gene mutations, history of high-risk proliferative changes, and prior hysterectomy were factors associated with women who were more likely to engage in risk-reducing strategies. These findings, when paired with patient reported outcome measures, may help guide shared decision-making.