Experience with Bilateral Risk-Reducing Mastectomy for an Unaffected BRCA Mutation Carrier

Efficacy of PARP Inhibitor, Platinum, and Immunotherapy in BRCA-Mutated HER2-Negative Breast Cancer Patients: A Systematic Review and Network Meta-Analysis

The optimal treatment regimen for breast cancer patients with gBRCA mutations remains controversial given the availability of numerous options, such as platinum-based agents, polymerase inhibitors (PARPis), and other agents. We included phase II or III RCTs and estimated the HR with 95% CI for OS, PFS, and DFS, in addition to the OR with 95% CI for ORR and pCR. We determined the treatment arm rankings by P-scores. Furthermore, we carried out a subgroup analysis in TNBC and HR-positive patients. We conducted this network meta-analysis using R 4.2.0 and a random-effects model. A total of 22 RCTs were eligible, involving 4253 patients. In the pairwise comparisons, PARPi + Platinum + Chemo was better than PARPi + Chemo for OS (in whole study group and in both subgroups) as well as PFS. The ranking tests demonstrated that PARPi + Platinum + Chemo ranked first in PFS, DFS, and ORR. Platinum + Chemo showed higher OS than PARPi + Chemo. The ranking tests for PFS, DFS, and pCR indicated that, except for the best treatment (PARPi + Platinum + Chemo) containing PARPi, the second and third treatments were platinum monotherapy or platinum-based chemotherapy. In conclusion, PARPi + Platinum + Chemo might be the best regime for gBRCA-mutated BC. Platinum drugs showed more favorable efficacy than PARPi in both combination and monotherapy.

Nipple-sparing mastectomy with immediate breast reconstruction - early complications and outcomes of the treatment

Aim of the study

To assess the early complications and outcomes of the treatment of patients undergoing nipple-sparing mastectomy (NSM) with immediate breast reconstruction.

Material and methods

A retrospective study was performed on 120 patients who underwent 130 NSM (10 bilateral) procedures between 1.01.2015 and 31.12.2017 in two oncology centers in Poland. In 80 patients a breast cancer was recognized. Sixteen patients underwent operations on the basis of being carriers of the BRCA1 mutation. The follow-up period ranged from 10 to 34 months. The NSM procedures were performed with or without skin reduction and a free nipple-areola complex (NAC) transplant, with 130 prosthetic devices inserted subpectorally. Breast cancer patients followed the standard protocol for adjuvant therapy.

Results

The patients for risk-reducing mastectomies were younger. Prevalent histology was no special type (NST) in 60 out of 80 patients, mean tumor - NAC distance was 43.3 mm. The prevalent biological subtype was Luminal B HER2-negative. Adjuvant management consisted of chemotherapy in 61 and radiotherapy in 35 patients. We noted 14 cases of complications, 13 in the cancer group, and 1 in the non-cancer group. Skin necrosis was the most common. The mean time for the appearance of the complications was 2.8 months. No local recurrences were observed.

Conclusions

NSM is a safe and effective surgical option for qualified patients with breast cancer and in risk-reducing mastectomies.

Evolving indications and long-term oncological outcomes of risk-reducing bilateral nipple-sparing mastectomy

Background

Bilateral nipple‐sparing mastectomy (NSM) is a technically feasible operation and is associated with excellent cosmetic outcomes. The aim of this study was to evaluate trends in patient characteristics, indications for surgery and long‐term outcomes of bilateral NSM for breast cancer risk reduction over time.

Methods

A review of a single‐centre experience with bilateral NSM performed between 2001 and 2017 for breast cancer risk reduction in patients without breast cancer was performed. Trends in patient characteristics and indications for surgery were evaluated over four time intervals: 2001–2005, 2006–2009, 2010–2013 and 2014–2017. Statistical analysis was performed using χ² tests.

Results

Over the study period, 272 NSMs were performed in 136 patients; their median age was 41 years. The number of bilateral NSMs performed increased over time. The most common indication was a mutation in breast cancer‐associated genes (104 patients, 76·5 per cent), which included BRCA1 (62 patients), BRCA2 (35), PTEN (2), TP53 (3) and ATM (2). Other indications were family history of breast cancer (19 patients, 14·0 per cent), lobular carcinoma in situ (10, 7·4 per cent) and a history of mantle irradiation (3, 2·2 per cent). The proportion of patients having a bilateral NSM for mutation in a breast cancer‐associated gene increased over time (2001–2005: 2 of 12; 2006–2009: 9 of 17; 2010–2013: 34 of 41; 2014–2017: 61 of 66; P < 0·001). Mean follow‐up was 53 months; no breast cancers were found during follow‐up.

Conclusion

The use of bilateral NSM for breast cancer risk reduction is increasing and the indications have evolved over the past 16 years. These excellent long‐term oncological results suggest that bilateral NSM is a good option for surgical breast cancer risk reduction.

Risk-reducing bilateral salpingo-oophorectomy in women with BRCA1 or BRCA2 mutations

BACKGROUND

The presence of deleterious mutations in breast cancer 1 gene (BRCA1) or breast cancer 2 gene (BRCA2) significantly increases the risk of developing some cancers, such as breast and high-grade serous cancer (HGSC) of ovarian, tubal and peritoneal origin. Risk-reducing salpingo-oophorectomy (RRSO) is usually recommended to BRCA1 or BRCA2 carriers after completion of childbearing. Despite prior systematic reviews and meta-analyses on the role of RRSO in reducing the mortality and incidence of breast, HGSC and other cancers, RRSO is still an area of debate and it is unclear whether RRSO differs in effectiveness by type of mutation carried.

OBJECTIVES

To assess the benefits and harms of RRSO in women with BRCA1 or BRCA2 mutations.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 7) in The Cochrane Library, MEDLINE Ovid, Embase Ovid and trial registries, with no language restrictions up to July 2017. We handsearched abstracts of scientific meetings and other relevant publications.

SELECTION CRITERIA

We included non-randomised trials (NRS), prospective and retrospective cohort studies, and case series that used statistical adjustment for baseline case mix using multivariable analyses comparing RRSO versus no RRSO in women without a previous or coexisting breast, ovarian or fallopian tube malignancy, in women with or without hysterectomy, and in women with a risk-reducing mastectomy (RRM) before, with or after RRSO.

DATA COLLECTION AND ANALYSIS

We extracted data and performed meta-analyses of hazard ratios (HR) for time-to-event variables and risk ratios (RR) for dichotomous outcomes, with 95% confidence intervals (CI). To assess bias in the studies, we used the ROBINS-I 'Risk of bias' assessment tool. We quantified inconsistency between studies by estimating the I² statistic. We used random-effects models to calculate pooled effect estimates.

MAIN RESULTS

We included 10 cohort studies, comprising 8087 participants (2936 (36%) surgical participants and 5151 (64%) control participants who were BRCA1 or BRCA2 mutation carriers. All the studies compared RRSO with or without RRM versus no RRSO (surveillance). The certainty of evidence by GRADE assessment was very low due to serious risk of bias. Nine studies, including 7927 women, were included in the meta-analyses. The median follow-up period ranged from 0.5 to 27.4 years.

MAIN OUTCOMES

overall survival was longer with RRSO compared with no RRSO (HR 0.32, 95% CI 0.19 to 0.54; P < 0.001; 3 studies, 2548 women; very low-certainty evidence). HGSC cancer mortality (HR 0.06, 95% CI 0.02 to 0.17; I² = 69%; P < 0.0001; 3 studies, 2534 women; very low-certainty evidence) and breast cancer mortality (HR 0.58, 95% CI 0.39 to 0.88; I² = 65%; P = 0.009; 7 studies, 7198 women; very low-certainty evidence) were lower with RRSO compared with no RRSO. None of the studies reported bone fracture incidence. There was a difference in favour of RRSO compared with no RRSO in terms of ovarian cancer risk perception quality of life (MD 15.40, 95% CI 8.76 to 22.04; P < 0.00001; 1 study; very low-certainty evidence). None of the studies reported adverse events.Subgroup analyses for main outcomes: meta-analysis showed an increase in overall survival among women who had RRSO versus women without RRSO who were BRCA1 mutation carriers (HR 0.30, 95% CI 0.17 to 0.52; P < 0001; I² = 23%; 3 studies; very low-certainty evidence) and BRCA2 mutation carriers (HR 0.44, 95% CI 0.23 to 0.85; P = 0.01; I² = 0%; 2 studies; very low-certainty evidence). The meta-analysis showed a decrease in HGSC cancer mortality among women with RRSO versus no RRSO who were BRCA1 mutation carriers (HR 0.10, 95% CI 0.02 to 0.41; I² = 54%; P = 0.001; 2 studies; very low-certainty evidence), but uncertain for BRCA2 mutation carriers due to low frequency of HGSC cancer deaths in BRCA2 mutation carriers. There was a decrease in breast cancer mortality among women with RRSO versus no RRSO who were BRCA1 mutation carriers (HR 0.45, 95% CI 0.30 to 0.67; I² = 0%; P < 0.0001; 4 studies; very low-certainty evidence), but not for BRCA2 mutation carriers (HR 0.88, 95% CI 0.42 to 1.87; I² = 63%; P = 0.75; 3 studies; very low-certainty evidence). One study showed a difference in favour of RRSO versus no RRSO in improving quality of life for ovarian cancer risk perception in women who were BRCA1 mutation carriers (MD 10.70, 95% CI 2.45 to 18.95; P = 0.01; 98 women; very low-certainty evidence) and BRCA2 mutation carriers (MD 13.00, 95% CI 3.59 to 22.41; P = 0.007; very low-certainty evidence). Data from one study showed a difference in favour of RRSO and RRM versus no RRSO in increasing overall survival (HR 0.14, 95% CI 0.02 to 0.98; P = 0.0001; I² = 0%; low-certainty evidence), but no difference for breast cancer mortality (HR 0.78, 95% CI 0.51 to 1.19; P = 0.25; very low-certainty evidence). The risk estimates for breast cancer mortality according to age at RRSO (50 years of age or less versus more than 50 years) was not protective and did not differ for BRCA1 (HR 0.85, 95% CI 0.64 to 1.11; I² = 16%; P = 0.23; very low-certainty evidence) and BRCA2 carriers (HR 0.88, 95% CI 0.42 to 1.87; I² = 63%; P = 0.75; very low-certainty evidence).

AUTHORS' CONCLUSIONS

There is very low-certainty evidence that RRSO may increase overall survival and lower HGSC and breast cancer mortality for BRCA1 and BRCA2 carriers. Very low-certainty evidence suggests that RRSO reduces the risk of death from HGSC and breast cancer in women with BRCA1 mutations. Evidence for the effect of RRSO on HGSC and breast cancer in BRCA2 carriers was very uncertain due to low numbers. These results should be interpreted with caution due to questionable study designs, risk of bias profiles, and very low-certainty evidence. We cannot draw any conclusions regarding bone fracture incidence, quality of life, or severe adverse events for RRSO, or for effects of RRSO based on type and age at risk-reducing surgery. Further research on these outcomes is warranted to explore differential effects for BRCA1 or BRCA2 mutations.

Nipple-sparing mastectomy in women at high risk of developing breast cancer

Nipple-sparing mastectomy is a valuable addition to the options available for women at high risk of developing breast cancer. In this review, we summarize current knowledge about the high-risk genes, BRCA1, BRCA2 and TP53 and the associated guidelines with regard to risk-reducing surgery. We consider other genetic risks and high-risk lesions. We discuss the literature on bilateral mastectomy for breast cancer risk-reduction, and the results of nipple-sparing mastectomy in particular. Finally, we report on patient satisfaction with these procedures and the impact that nipple-sparing mastectomy may have on women at high-risk of breast cancer.