Clinical behavior and outcomes of breast cancer in young women with germline BRCA pathogenic variants

Impact of hormone receptor status and tumor subtypes of breast cancer in young BRCA carriers

BACKGROUND

Hormone receptor expression is a known positive prognostic and predictive factor in breast cancer; however, limited evidence exists on its prognostic impact on prognosis of young patients harboring a pathogenic variant (PV) in the BRCA1 and/or BRCA2 genes.

PATIENTS AND METHODS

This international, multicenter, retrospective cohort study included young patients (aged ≤40 years) diagnosed with invasive breast cancer and harboring germline PVs in BRCA genes. We investigated the impact of hormone receptor status on clinical behavior and outcomes of breast cancer. Outcomes of interest [disease-free survival (DFS), breast cancer-specific survival (BCSS), and overall survival (OS)] were first investigated according to hormone receptor expression (positive versus negative), and then according to breast cancer subtype [luminal A-like versus luminal B-like versus triple-negative versus human epidermal growth factor receptor 2 (HER2)-positive breast cancer].

RESULTS

From 78 centers worldwide, 4709 BRCA carriers were included, of whom 2143 (45.5%) had hormone receptor-positive and 2566 (54.5%) hormone receptor-negative breast cancer. Median follow-up was 7.9 years. The rate of distant recurrences was higher in patients with hormone receptor-positive disease (13.1% versus 9.6%, P < 0.001), while the rate of second primary breast cancer was lower (9.1% versus 14.7%, P < 0.001) compared to patients with hormone receptor-negative disease. The 8-year DFS was 65.8% and 63.4% in patients with hormone receptor-positive and negative disease, respectively. The hazard ratio of hormone receptor-positive versus negative disease changed over time for DFS, BCSS, and OS (P < 0.05 for interaction of hormone receptor status and survival time). Patients with luminal A-like breast cancer had the worst long-term prognosis in terms of DFS compared to all the other subgroups (8-year DFS: 60.8% in luminal A-like versus 63.5% in triple-negative versus 65.5% in HER2-positive and 69.7% in luminal B-like subtype).

CONCLUSIONS

In young BRCA carriers, differences in recurrence pattern and second primary breast cancer among hormone receptor-positive versus negative disease warrant consideration in counseling patients on treatment, follow-up, and risk-reducing surgery.

Can contralateral prophylactic mastectomy and oophorectomy increase survival in BRCA-related breast cancer? Results from the Italian MUTina study

INTRODUCTION

In the Emilia-Romagna region of Italy, a unique Hub and Spoke model was adopted to recognize BRCA-related breast cancer (BC) patients. Characteristics and outcomes of tumors identified by this model will be presented.

METHODS

This multicenter retrospective cohort study involved patients diagnosed with BRCA-related BC identified in the Emilia-Romagna region between January 2000 and December 2013. Seven provinces collected data on patient and tumor characteristics; clinical and gene testing information were also registered. Comparisons between BRCA1 and BRCA2 BC were performed. To balance different variants to identify significant predictors of survival, an inverse probability of treatment weighting (IPTW) analysis on Cox regression was conducted.

RESULTS

From 2000 to 2013, 284 BRCA-related BC were registered (171 BRCA1, 110 BRCA2, and 3 BRCA1 and BRCA2). BRCA1 were diagnosed at an earlier stage compared to BRCA2 (50.1 % vs 30 %, respectively, in stage I, P = 0.0015). BRCA2 patients underwent more up-front surgery (85 % vs. 74.9 %, P = 0.049) and less chemotherapy (69.1 % vs 88.9 %, P = 0.004) than BRCA1 patients. At 11.8 years median follow-up, BRCA1 patients developed more second contralateral BC (P = 0.09), while BRCA2 had more visceral relapses (P = 0.013). No differences in overall survival (OS) between BRCA1 and BRCA2 patients (P = 0.07) were found. An advantage in OS was independently seen for patients who underwent contralateral prophylactic mastectomy (P = 0.0001) and oophorectomy (P < 0.0001).

CONCLUSIONS

In conclusion, adopting a homogeneous regional framework provides important information about prevention and treatment strategies of BRCA-related BC and suggests using maximal surgery to improve OS.

Low testing rates and high BRCA prevalence: Poly (ADP-ribose) polymerase inhibitor use in Middle East BRCA/homologous recombination deficiency-positive cancer patients

BACKGROUND

Poly (ADP-ribose) polymerase inhibitors (PARPis) are approved as first-line therapies for breast cancer gene (BRCA)-positive, human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer. They are also effective for new and recurrent ovarian cancers that are BRCA- or homologous recombination deficiency (HRD)-positive. However, data on these mutations and PARPi use in the Middle East are limited.

AIM

To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.

METHODS

This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations, and 25 of 65 ovarian cancer patients tested for HRD. These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023. Data were summarized using descriptive statistics and compared using counts and percentages. Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.

RESULTS

Among the 472 breast cancer patients, 12.1% underwent BRCA testing, and 38.5% of 65 ovarian cancer patients received HRD testing. Pathogenic mutations were found in 25.6% of the tested patients: 26.3% breast cancers had germline BRCA (gBRCA) mutations and 24.0% ovarian cancers showed HRD. Notably, 40.0% of gBRCA-positive breast cancers and 66.0% of HRD-positive ovarian cancers were Middle Eastern and Asian patients, respectively. PARPi treatment was used in 5 (33.3%) gBRCA-positive breast cancer patients as first-line therapy (n = 1; 7-months progression-free), for maintenance (n = 2; > 15-months progression-free), or at later stages due to compliance issues (n = 2). Four patients (66.6%) with HRD-positive ovarian cancer received PARPi and all remained progression-free.

CONCLUSION

Lower testing rates but higher BRCA mutations in breast cancer were found. Ethnicity reflected United Arab Emirates demographics, with breast cancer in Middle Eastern and ovarian cancer in Asian patients.

Helping ourselves, helping others: the Young Women's Breast Cancer Study (YWS) - a multisite prospective cohort study to advance the understanding of breast cancer diagnosed in women aged 40 years and younger

PURPOSE

Compared with older women diagnosed with breast cancer, younger women are more likely to die of breast cancer and more likely to suffer psychosocially in both the short-term and long term. The Young Women's Breast Cancer Study (YWS) is a multisite prospective cohort study established to address gaps in our knowledge about this vulnerable and understudied population.

PARTICIPANTS

The YWS enrolled 1302 women newly diagnosed with stages 0-IV breast cancer at age 40 years or younger at 13 academic and community sites in North America between 2006 and 2016. Longitudinal patient-reported outcome data are complemented by clinical data abstraction and biospecimen collection at multiple timepoints.

FINDINGS TO DATE

Key findings related to fertility include that nearly 40% of participants were interested in pregnancy following diagnosis; of those who reported interest, 10% pursued fertility preservation. Overall, approximately 10% of YWS participants became pregnant in the first 5 years after diagnosis; follow-up is ongoing for pregnancies after 5 years. Studies focused on psychosocial outcomes have characterised quality of life, post-traumatic stress and fear of recurrence, with findings detailing the factors associated with the substantial psychosocial burden many young women face during and following active treatment. Multiple studies have leveraged YWS biospecimens, including whole-exome sequencing of tumour analyses that revealed that select somatic alterations occur at different frequencies in young (age≤35) versus older women with luminal A breast cancer, and a study that explored clonal hematopoiesis of indeterminate potential found it to be rare in young survivors.

FUTURE PLANS

With a median follow-up of approximately 10 years, the cohort is just maturing for many relevant long-term outcomes and provides outstanding opportunities to further study and build collaborations to address gaps in our knowledge, with the ultimate objective to improve care and outcomes for young women with breast cancer.

TRIAL REGISTRATION NUMBER

NCT01468246.

Genetic counseling and genetic testing for pathogenic germline mutations among high-risk patients previously diagnosed with breast cancer: a traceback approach

Genetic counseling and testing are more accessible than ever due to reduced costs, expanding indications and public awareness. Nonetheless, many patients missed the opportunity of genetic counseling and testing due to barriers that existed at that time of their cancer diagnoses. Given the identified implications of pathogenic mutations on patients' treatment and familial outcomes, an opportunity exists to utilize a 'traceback' approach to retrospectively examine their genetic makeup and provide consequent insights to their disease and treatment. In this study, we identified living patients diagnosed with breast cancer (BC) between July 2007 and January 2022 who would have been eligible for testing, but not tested. Overall, 422 patients met the eligibility criteria, 282 were reached and invited to participate, and germline testing was performed for 238, accounting for 84.4% of those invited. The median age (range) was 39.5 (24-64) years at BC diagnosis and 49 (31-75) years at the date of testing. Genetic testing revealed that 25 (10.5%) patients had pathogenic/likely pathogenic (P/LP) variants; mostly in BRCA2 and BRCA1. We concluded that long overdue genetic referral through a traceback approach is feasible and effective to diagnose P/LP variants in patients with history of BC who had missed the opportunity of genetic testing, with potential clinical implications for patients and their relatives.

HR-positive/HER2-negative breast cancer arising in patients with or without BRCA2 mutation: different biological phenotype and similar prognosis

Background

BRCA2 plays a key role in homologous recombination. However, information regarding its mutations in Chinese patients with breast cancer remains limited.

Objectives

This study aimed to assess the clinicopathological characteristics of BRCA2 mutation breast cancer and explore the mutation's effect on hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer survival in China.

Design

This hospital-based cohort study prospectively included 629 women with breast cancer diagnosed from 2008 to 2023 at Zhejiang Cancer Hospital in China.

Methods

We compared the clinicopathological characteristics and metastatic patterns and analysed the invasive disease-free survival (iDFS), distant relapse-free survival (DRFS) and first-line progression-free survival (PFS1) of patients with HR-positive/HER2-negative breast cancer according to BRCA2 mutations.

Results

Among the 629 patients, 78 had BRCA2 mutations (12.4%) and 551 did not (87.6%). The mean age at diagnosis was lower in the BRCA2 mutation breast cancer group than in the non-mutation breast cancer group (38.91 versus 41.94 years, p = 0.016). BRCA2 mutation breast cancers were more likely to be lymph node-positive than non-mutation breast cancers (73.0% versus 56.6%, p = 0.037). The pathological grade was higher in 47.1% of BRCA2 mutation breast cancers than in 29.6% of non-mutation breast cancers (p = 0.014). The proportions of patients with BRCA2 mutations who developed contralateral breast cancer (19.2% versus 8.8%, p = 0.004), breast cancer in the family (53.8% versus 38.3%, p = 0.009) and ovarian cancer in the family (7.6% versus 2.4%, p = 0.022) were higher than those of patients without the mutation. The median follow-up time was 92.78 months. Multivariate analysis showed that BRCA2 mutation was not associated with poorer iDFS [hazard ratio = 0.9, 95% confidence interval (CI) = 0.64-1.27, p = 0.56] and poorer distant relapse-free survival (DRFS) (hazard ratio = 1.09, 95% CI = 0.61-1.93, p = 0.76). There was no significant difference between the two groups with regard to metastatic patterns in the advanced disease setting. In the first-line metastatic breast cancer setting, PFS1 expression was broadly similar between the two groups irrespective of chemotherapy or endocrine therapy.

Conclusion

HR-positive/HER2-negative breast cancer with BRCA2 mutations differs from those without mutations in clinical behaviour and reflects more aggressive tumour behaviour. Our results indicate that BRCA2 mutations have no significant effect on the survival of Chinese women with HR-positive/HER2-negative breast cancer.

Subtype-Specific Survival of Young Women with Breast Cancer and Its Interaction with the Germline BRCA Status

Data are scarce on the role of pathogenic germline variants in BRCA1 and BRCA2 (gBRCAm) in subtype-specific survival in young women who develop breast cancer under the age of 40. This retrospective, real-world cohort study assessed the distant disease-free survival (DDFS) and overall survival (OS) of young women diagnosed with breast cancer between 2008 and 2019 while taking into consideration the interaction of clinical subtypes and the gBRCA status. Among 473 women, HR+/Her2- was the most common subtype (49.0%), followed by TNBC (31.3%), HR+/Her2+ (13.7%), and Her2+/HR- (5.9%). The gBRCA status was known for 319 cases (gBRCAwt (wild-type - without pathogenic variants in BRCA1 or BRCA2): 204, gBRCA1m: 83, gBRCA2m: 31, 1 patient with both). The distribution of clinical subtypes varied depending on the gBRCA status (p < 0.001). In survival analysis with a median follow-up of 43 months, the unadjusted DDFS and OS were worse for gBRCAwt TNBC compared to both HR+ subtypes, but not for gBRCAm TNBC patients. T-stage, nodal involvement, and the gBRCA status were identified as significant for survival in TNBC. In TNBC, gBRCAm was associated with better DDFS and OS than gBRCAwt (5-year DDFS 81.4% vs. 54.3%, p = 0.012 and 5-year OS 96.7% vs. 62.7%, p < 0.001). In contrast, in HR+/Her2- patients, gBRCAm patients showed a tendency for worse survival, though not statistically significant. Subtype-specific survival in young women with breast cancer needs to be evaluated in interaction with the gBRCA status. For TNBC, gBRCAm is of favorable prognostic value for overall survival, while patients with gBRCAwt TNBC need to be considered to have the highest risk for adverse survival outcomes.

EXPRESSION PROFILE OF miR-145, -182, -21, -27a, -29b, and -34a IN BREAST CANCER PATIENTS OF YOUNG AGE

BACKGROUND

Breast cancer (BC) in young women remains a significant public health concern. While progress has been made in understanding the etiology, diagnosis, and treatment of BC in this population, challenges persist. The identification and utilization of prognostic biomarkers offer valuable tools for tailoring treatment strategies and improving outcomes for BC patients.

AIM

To evaluate the relationship between the expression of tumor-associated microRNAs and the clinical and pathological features of BC in young patients.

MATERIALS AND METHODS

The work is based on the results of the examination and treatment of 50 women younger than 45 years with stage I-II BC. miR-145, -182, -21, -27a, -29b, and -34a expression in tumor samples was analyzed by the real-time reverse transcription polymerase chain reaction.

RESULTS

Higher expression of miR-182, -21, and -29b and lower levels of miR-27a were associated with tumor stage in young BC patients. Patients without lymph node metastases (N0) had significantly higher levels of miR-182, -27a, and -34a and lower levels of miR-29b compared to N1 cases (p < 0.05). Expression of miR-145, -182, -21, -27a, and -29b was associated with molecular BC subtypes.

CONCLUSION

Obtained results show that a high malignancy degree of BC in young women is associated with an increase in the miR-182, -21, -29b, and -34a expressions and a decrease in the miR-27a level in the tumor tissue, which indicates the prospects of the use of them for predicting the aggressiveness of the disease.

Survival Outcomes and Efficacy of Platinum in Early Breast Cancer Patients with Germline BRCA1 or BRCA2 Mutation: A Multicenter Retrospective Cohort Study

Purpose

The study aimed to compare the survival outcomes and efficacy of platinum in early breast cancer patients with BRCA1 and BRCA2 mutations.

Methods

Patients diagnosed with stage I-III breast cancer and carrying germline pathogenic/likely pathogenic BRCA mutations in three medical institutions in China from April 2016 to January 2021 were retrospectively analyzed. Data on clinical and pathological characteristics, treatment information, pathogenic variants of BRCA, and survival outcomes were collected for all eligible patients.

Outcomes

One hundred and sixty-nine patients with BRCA mutations were enrolled, including BRCA1 mutation (53.3%, n = 90) and BRCA2 mutation (46.7%, n = 79). The median age was 39 years, and most patients (68.1%, n = 115) were stage I-II. Patients with BRCA1 mutations were characterized by histological grade III (55.6%) and higher Ki-67 index (Ki-67 ≥ 30%, 78.9%) compared with patients with BRCA2 mutations (27.8%, 58.2%). BRCA1 mutation patients accounted for a significantly higher proportion of triple negative breast cancer than BRCA2 mutation patients (71.1% vs 19.0%, P < 0.0001). A total of 142 (84.0%) patients received neo/adjuvant chemotherapy, including anthracycline and/or taxane-based regimens (55.6%) or platinum-based regimens (27.2%). Median follow-up was 33.2 months. Three-year DFS (disease-free survival) and DRFS (distant recurrence-free survival) had no significant differences between patients with BRCA1 and BRCA2 mutations (82.0% vs 85.4%, P = 0.35; 94.3% vs 94.6%, P = 0.39). The 3-year DFS rate in BRCA1 mutation cohort of patients received platinum regimen was significantly higher than patients received non-platinum regimen (96.0% vs 75.2%, P = 0.01). No differences between DFS and DRFS were observed in patients with BRCA2 mutation received platinum regimen and non-platinum regimen.

Conclusion

Similar survival outcomes were observed in early breast cancer patients with BRCA1 and BRCA2 mutation, though they had different biological characteristics. Patients with BRCA1 mutations are more benefit from platinum-regimen. The value of platinum-regimen for early breast cancer patients with BRCA1 and BRCA2 needs to be verified further.

Progress and prospects in research and clinical practice of hormone receptor-positive, HER-2-negative breast cancer with BRCA1/2 mutations

Breast cancer (BC) is a heterogeneous disease that is the most common cancer in women worldwide. However, precise subtyping and corresponding treatments have improved patient outcomes. Hormone receptor (HR)-positive, human epidermal growth factor receptor type 2 (HER2)-negative (HR+/HER2-) BC with BRCA1 and/or BRCA2 mutations (BRCA1/2m) is a unique BC subset with dual drivers: homologous recombination deficiency and hormone receptor signaling. Wild-type BRCA1/2 suppresses estrogen receptor-mediated signaling. Loss-of-function mutations in BRCA1/2 release estrogen receptor suppression, leading to reduced sensitivity to endocrine therapy. Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis) exert antitumor effects against this subtype and can be used in combination with endocrine therapy. Although PARPis have been evaluated in metastatic triple-negative breast cancer, their efficacy against HR+/HER2- BC has not been clearly established. The present review summarizes recent advances and prospects in the progress of the HR+/HER2-/BRCA1/2m subgroup. As such, this article provides theoretical guidance for future research and promotes the use of PARPis for the treatment of HR+/HER2-/BRCA1/2m BC.

Adjuvant Olaparib for Germline BRCA Carriers With HER2-Negative Early Breast Cancer: Evidence and Controversies

In the OlympiA study, 1 year of adjuvant olaparib significantly extended invasive disease-free survival and overall survival. The benefit was consistent across subgroups, and this regimen is now recommended after chemotherapy for germline BRCA1/2 mutation (gBRCA1/2m) carriers with high-risk, HER2-negative early breast cancer. However, the integration of olaparib in the landscape of agents currently available in the post(neo)adjuvant setting-ie, pembrolizumab, abemaciclib, and capecitabine-is challenging, as there are no data suggesting how to select, sequence, and/or combine these therapeutic approaches. Furthermore, it is unclear how to best identify additional patients who could benefit from adjuvant olaparib beyond the original OlympiA criteria. Since it is unlikely that new clinical trials will answer these questions, recommendations for clinical practice can be made through indirect evidence. In this article, we review available data that could help guide treatment decisions for gBRCA1/2m carriers with high-risk, early-stage breast cancer.

Early breast cancer in women aged 35 years or younger: A large national multicenter French population-based case control-matched analysis

BACKGROUND

There is a scarcity of data exploring early breast cancer (eBC) in very young patients. We assessed shared and intrinsic prognostic factors in a large cohort of patients aged ≤35, compared to a control group aged 36 to 50.

METHODS

Patients ≤50 were retrospectively identified from a multicentric cohort of 23,134 eBC patients who underwent primary surgery between 1990 and 2014. Multivariate Cox analyses for DFS and OS were built. To assess the independent impact of age, 1 to 3 case-control analysis was performed by matching ≤35 and 36-50 years patients.

RESULTS

Of 6481 patients, 556 were aged ≤35, and 5925 from 36 to 50. Age ≤35 was associated with larger tumors, higher grade, ER-negativity, macroscopic lymph node involvement (pN + macro), lymphovascular invasion (LVI), mastectomy, and chemotherapy (CT) use. In multivariate analysis, age ≤35 was associated with worse DFS [HR 1.56, 95% CI 1.32-1.84; p < 0.001], and OS [HR 1.29, 95% CI 1.03-1.60; p = 0.025], as were high grade, large tumor, LVI, pN + macro, ER-negativity, period of diagnostic, and absence of ET or CT (for DFS). Adverse prognostic impact of age ≤35 was maintained in the case control-matched analysis for DFS [HR 1.56, 95%CI 1.28-1.91, p < 0.001], and OS [HR 1.33, 95%CI 1.02-1.73, p = 0.032]. When only considering patients ≤35, ER, tumor size, nodal status, and LVI were independently associated with survival in this subgroup.

CONCLUSIONS

Age ≤35 is associated with less favorable presentation and more aggressive treatment strategies. Our results support the poor prognosis value of young age, which independently persisted when adjusting for other prognostic factors and treatments.

What Is Known about Breast Cancer in Young Women?

Breast cancer (BC) is the second leading cause of cancer-related death in women under the age of 40 years worldwide. In addition, the incidence of breast cancer in young women (BCYW) has been rising. Young women are not the focus of screening programs and BC in younger women tends to be diagnosed in more advanced stages. Such patients have worse clinical outcomes and treatment complications compared to older patients. BCYW has been associated with distinct tumour biology that confers a worse prognosis, including poor tumour differentiation, increased Ki-67 expression, and more hormone-receptor negative tumours compared to women >50 years of age. Pathogenic variants in cancer predisposition genes such as BRCA1/2 are more common in early-onset BC compared to late-onset BC. Despite all these differences, BCYW remains poorly understood with a gap in research regarding the risk factors, diagnosis, prognosis, and treatment. Age-specific clinical characteristics or outcomes data for young women are lacking, and most of the standard treatments used in this subpopulation currently are derived from older patients. More age-specific clinical data and treatment options are required. In this review, we discuss the epidemiology, clinicopathologic characteristics, outcomes, treatments, and special considerations of breast cancer in young women. We also underline future directions and highlight areas that require more attention in future studies.

Loss of Brca1 and Trp53 in adult mouse mammary ductal epithelium results in development of hormone receptor-positive or hormone receptor-negative tumors, depending on inactivation of Rb family proteins

BACKGROUND

Breast cancer is a heterogenous disease with several histological and molecular subtypes. Models that represent these subtypes are essential for translational research aimed at improving clinical strategy for targeted therapeutics.

METHODS

Different combinations of genetic aberrations (Brca1 and Trp53 loss, and inhibition of proteins of the Rb family) were induced in the mammary gland by injection of adenovirus expressing Cre recombinase into the mammary ducts of adult genetically engineered mice. Mammary tumors with different genetic aberrations were classified into molecular subtypes based on expression of molecular markers and RNAseq analysis. In vitro potency assays and Western blots were used to examine their drug sensitivities.

RESULTS

Induction of Brca1 and Trp53 loss in mammary ductal epithelium resulted in development of basal-like hormone receptor (HR)-negative mammary tumors. Inhibition of Rb and Trp53 loss or the combination of Rb, Trp53 and Brca1 aberrations resulted in development of luminal ductal carcinoma positive for ER, PR, and Her2 expression. HR positivity in tumors with Rb, Trp53 and Brca1 aberrations indicated that functionality of the Rb pathway rather than Brca1 status affected HR status in these models. Mammary tumor gene expression profiles recapitulated human basal-like or luminal B breast cancer signatures, but HR-positive luminal cancer models were endocrine resistant and exhibited upregulation of PI3K signaling and sensitivity to this pathway inhibition. Furthermore, both tumor subtypes were resistant to CDK4/6 inhibition.

CONCLUSIONS

Examination of molecular expression profiles and drug sensitivities of tumors indicate that these breast cancer models can be utilized as a translational platform for evaluation of targeted combinations to improve chemotherapeutic response in patients that no longer respond to hormone therapy or that are resistant to CDK4/6 inhibition.

Cyclin-Dependent Kinase 4/6 Inhibitor Outcomes in Patients With Advanced Breast Cancer Carrying Germline Pathogenic Variants in DNA Repair-Related Genes

PURPOSE

In recent years, unprecedented benefits have been observed with the development of cyclin-dependent kinase (CDK) 4 and 6 inhibitors for the treatment of hormone receptor-positive/human epidermal growth factor receptor 2-negative metastatic breast cancer. However, there is scarce evidence of their value in specific populations, such as patients carrying germline pathogenic variants in DNA repair-related genes.

PATIENTS AND METHODS

We retrospectively studied the efficacy of CDK 4/6 inhibitors plus endocrine therapy in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer. Three cohorts were compared, including patients harboring germline pathogenic variants in DNA repair-related genes (gBRCA1/2-ATM-CHEK2 mutated), those tested without these mutations (wild type [WT]), and the nontested subgroup. Relevant prognostic factors including age, metastatic site (visceral v nonvisceral), Eastern Cooperative Oncology Group, and prior treatment with CDK 4/6 inhibitors were stratified by univariate and multivariate Cox regression models.

RESULTS

Among the total population (n = 217), 15 (6.9%) patients carried gBRCA1/2 (n = 10)-ATM (n = 4)-CHEK2 (n = 1) pathogenic variants, 45 (20.7%) were WT, and 157 (72.4%) were nontested. Gene pathogenic variant carriers were younger (P < .001). Most patients (164, 75.6%) had not received prior endocrine therapy in the advanced setting. Median progression-free survival was shorter in patients with evaluated germline pathogenic variants (10.2 months [95% CI, 5.7 to 14.7]), compared with WT and nontested patients (15.6 months [95% CI, 7.8 to 23.4], and (17.6 months [95% CI, 12.9 to 22.2]; P = .002). Consistently, a worse median overall survival was observed in the subgroup with germline pathogenic variants than in the WT group (P = .006). Multivariable analysis showed that mutation status was an independent prognostic factor of progression-free survival (P = .020) and overall survival (P = .012).

CONCLUSION

In this retrospective real-world study, gBRCA1/2-ATM-CHEK2 pathogenic variants were independently associated with poor outcomes in patients with advanced breast cancer treated with CDK4/6 inhibitors.

De novo Metastatic Breast Cancer Arising in Young Women: Review of the Current Evidence

Women with metastatic breast cancer remains a heterogeneous group of patients with different prognostic outcomes and therapeutic needs. Young women with de novo metastatic breast cancer (dnMBC) represent a peculiar population with respect to tumor biology, prognosis, clinical management and survivorship issues. Overall, these patients are able to attain long-term survival with a proper management of both primary tumor and distant metastases. On the other hand, they are also at higher risk of experiencing a deterioration in their quality of life (QoL) due to primary cancer-related side effects. Young women are also likely to harbor germline pathogenic variants in cancer predisposition genes which could affect treatment decisions and have a direct impact on the lives of patients' relatives. The loco-regional management of the primary tumor represents another thorny subject, as the surgical approach has shown controversial effects on the survival and the QoL of these patients. This review aims to provide an update on these issues to better inform the clinical management of dnMBC in young women.

Surgical management of BRCA pathogenic variant carriers with breast cancer: a recent literature review and current state of the art

INTRODUCTION

Surgical management of breast cancer patients carrying pathogenic variants (PV) on breast cancer genes (BRCA) 1 and 2 has changed throughout the last decade due to growing availability of genetic testing, and has shifted towards the diffusion of bilateral mastectomy. Today's scenario however is in further evolution because of emerging data that suggest a personalized modulation of treatment. In this work we aimed to gather recent evidence supporting a prophylactic or conservative surgical approach in order to define the state of the art in today's treatment of BRCA carriers with breast cancer.

EVIDENCE ACQUISITION

We reviewed the literature to identify studies providing evidence on surgical treatment in breast cancer patients with BRCA 1 and 2 PVs. We included articles comparing outcomes between patients undergoing breast conserving surgery (BCS) and mastectomy, and articles investigating contralateral risk-reducing mastectomy (CRRM), with a particular focus on recent literature. International guidelines were also reviewed.

EVIDENCE SYNTHESIS

Optimal surgical management of BRCA PV carriers with breast cancer remains controversial. While the introduction of routine genetic testing has initially led surgeons to favor more radical treatments, recent literature provides evidence that a conservative approach is safe and feasible in selected cases. Guidelines are heterogeneous and provide guidance without constraining the surgeon.

CONCLUSIONS

Patients should undergo adequate genetic and surgical counseling in order to receive the best tailored surgical treatment. Because guidelines vary in different countries and provide no definite protocol, they highlight the importance of accurate surgical planning. Clinical, familial and psychosocial factors should be taken into account when approaching a BRCA PV carrier with breast cancer, in order to guarantee the best evidence-based patient care in an era of personalized treatment.

Cancer-Specific Survival Outcome in Early-Stage Young Breast Cancer: Evidence From the SEER Database Analysis

BACKGROUND

Young women with breast cancer are determined to present poorer survival compare with elderly patients. Therefore, identifying the clinical prognostic factors in young women with early-stage (T_1-2N_0-1M₀) breast cancer is pivotal for surgeons to make better postoperative management.

METHODS

The clinicopathological characteristics of female patients with early-stage breast cancer from the Surveillance, Epidemiology, and End Results program between Jan 2010 and Dec 2015 were retrospectively reviewed and analyzed. Univariate and multivariate Cox regression analyses were used to determine the potential risk factors of cancer-specific survival in young women with early-stage breast cancer. The nomogram was constructed and further evaluated by an internal validation cohort. The Kaplan-Meier survival curves were used to estimate cancer-specific survival probability and the cumulative incidence.

RESULTS

Six variables including race, tumor location, grade, regional lymph node status, tumor subtype, and size were identified to be significantly associated with the prognosis of young women with early-stage breast cancer during the postoperative follow-up. A nomogram for predicting the 3-, 5- year cancer-specific survival probability in this subpopulation group was established with a favorable concordance index of 0.783, supported by an internal validation cohort with the AUC of 0.722 and 0.696 in 3-, 5- year cancer-specific survival probability, respectively.

CONCLUSIONS

The first predictive nomogram containing favorable discrimination is successfully established and validated for predicting the 3-, 5- year cancer-specific survival probability in young women with early-stage breast cancer during the postoperative follow-up. This model would help clinicians to make accurate treatment decisions in different clinical risk population.