Improved Breast Cancer-specific Survival Research Articles

Prognosis and treatment outcomes for patients with stage IA triple-negative breast cancer

To evaluate the role of chemotherapy in stage IA triple-negative breast cancer, we conducted a retrospective population-based study including 8601 patients. The use of chemotherapy significantly increased from 2010 to 2019 in patients with T1b and T1c tumors (p = 0.001 and p < 0.001, respectively). Receipt of chemotherapy was associated with improved breast cancer-specific survival (BCSS, adjusted hazard ratio = 0.70; p = 0.006), particularly in patients with T1c tumors (5-year BCSS 94.5% vs. 91.2%).

Stromal Type I Collagen in Breast Cancer: Correlation to Prognostic Biomarkers and Prediction of Chemotherapy Response

IntroductionFibrillar collagens accumulate in the breast cancer stroma and appear as poorly defined spiculated masses in mammography imaging. The prognostic value of tissue type I collagen remains elusive in treatment-naïve and chemotherapy-treated breast cancer patients. Here, type I collagen mRNA and protein expression were analysed in 2 large independent breast cancer cohorts. Levels were related to clinicopathological parameters, prognostic biomarkers, and outcome. MethodCOL1A1 mRNA expression was analysed in 2509 patients with breast cancer obtained from the cBioPortal database. Type I collagen protein expression was studied by immunohistochemistry in 1395 women diagnosed with early invasive breast cancer. ResultsLow COL1A1 mRNA and protein levels correlated with poor prognosis features, such as hormone receptor negativity, high histological grade, triple-negative subtype, node positivity, and tumour size. In unadjusted analysis, high stromal type I collagen protein expression was associated with improved overall survival (OS) (HR = 0.78, 95% CI = 0.61-0.99, p = .043) and trended towards improved breast cancer–specific survival (BCSS) (HR = 0.65, 95% CI = 0.42-1.01, P = 0.053), although these findings were lost after adjustment for other clinical variables. In unadjusted analysis, high expression of type I collagen was associated with better OS (HR = 0.70, 95% CI = 0.55-0.90, P = .006) and BCSS (HR = 0.55, 95% CI = 0.34-0.88, P = .014) among patients not receiving chemotherapy. Strikingly, the opposite was observed among patients receiving chemotherapy. There, high expression of type I collagen was instead associated with worse OS (HR = 1.83, 95% CI = 0.65-5.14, P = .25) and BCSS (HR = 1.72, 95% CI = 0.54-5.50, P = .357). ConclusionLow stromal type I collagen mRNA and protein expression are associated with unfavourable tumour characteristics in breast cancer. Stromal type I collagen might predict chemotherapy response.

The Sin3A/MAD1 Complex, through Its PAH2 Domain, Acts as a Second Repressor of Retinoic Acid Receptor Beta Expression in Breast Cancer Cells

Retinoids are essential in balancing proliferation, differentiation and apoptosis, and they exert their effects through retinoic acid receptors (RARs) and retinoid X receptors (RXRs). RARβ is a tumor-suppressor gene silenced by epigenetic mechanisms such as DNA methylation in breast, cervical and non-small cell lung cancers. An increased expression of RARβ has been associated with improved breast cancer-specific survival. The PAH2 domain of the scaffold protein SIN3A interacts with the specific Sin3 Interaction Domain (SID) of several transcription factors, such as MAD1, bringing chromatin-modifying proteins such as histone deacetylases, and it targets chromatin for specific modifications. Previously, we have established that blocking the PAH2-mediated Sin3A interaction with SID-containing proteins using SID peptides or small molecule inhibitors (SMI) increased RARβ expression and induced retinoic acid metabolism in breast cancer cells, both in in vitro and in vivo models. Here, we report studies designed to understand the mechanistic basis of RARβ induction and function. Using human breast cancer cells transfected with MAD1 SID or treated with the MAD SID peptide, we observed a dissociation of MAD1, RARα and RARβ from Sin3A in a coimmunoprecipitation assay. This was associated with increased RARα and RARβ expression and function by a luciferase assay, which was enhanced by the addition of AM580, a specific RARα agonist; EMSA showed that MAD1 binds to E-Box, similar to MYC, on the RARβ promoter, which showed a reduced enrichment of Sin3A and HDAC1 by ChIP and was required for the AM580-enhanced RARβ activation in MAD1/SID cells. These data suggest that the Sin3A/HDAC1/2 complex co-operates with the classical repressors in regulating RARβ expression. These data suggest that SIN3A/MAD1 acts as a second RARβ repressor and may be involved in fine-tuning retinoid sensitivity.

Association Between Regional Nodal Irradiation and Breast Cancer Recurrence-Free Interval for Patients With Low-Risk, Node-Positive Breast Cancer

Randomized clinical trials have shown that regional nodal irradiation (RNI) in patients with unselected N1 breast cancer improves breast cancer-specific survival. However, the benefit of RNI in women with biologically low-risk N1 breast cancer is uncertain. We conducted a population-based study to determine whether RNI is associated with improved breast cancer recurrence-free interval (BCRFI) in this population. Patients aged 40 to 79 years with pT1-2 pN1 (node-positive) breast cancer diagnosed between 2005 and 2014 were identified. The inclusion criteria were modeled off of the TAILOR RT study, which is a randomized noninferiority clinical trial designed to assess the value of RNI in patients with low-risk N1 disease. Eligible patients had breast-conserving surgery or mastectomy and axillary lymph node dissection with 1 to 3 positive nodes, breast-conserving surgery and sentinel lymph node biopsy with 1 to 2 positive nodes, or mastectomy and sentinel lymph node biopsy with 1 positive node. Additionally, patients had luminal A breast cancers, as approximated by estrogen receptor positive (Allred 6-8/8), progesterone receptor (PR) positive (Allred 6-8/8), human epidermal growth factor receptor 2-negative, and grade 1 to 2 immunohistochemical testing. All patients were prescribed hormonal treatment. The primary endpoint of BCRFI, the time to any breast cancer recurrence or breast cancer-related death, was analyzed using a multivariate competing risks analysis. The cohort included 1169 women with a median follow-up of 9.2 years. Radiation treatments were not performed in 151 women treated with mastectomy alone, were delivered to the breast only in 133 women, and were delivered locoregionally in 885 women. Patients undergoing RNI were younger (median age: 58 vs 62 years), more likely to have 2 to 3 macroscopic lymph nodes involved, and more often received chemotherapy (all P < .05). The 10-year estimate of BCRFI was 90% without RNI versus 90% with RNI (P=.5). On multivariable analysis, RNI was not a significant predictor of BCRFI (hazard ratio: 1.0; P=.9). In this retrospective analysis, RNI was not associated with improved BCRFI for women with biologically low-risk N1 breast cancer. We advocate accrual to the ongoing TAILOR RT study.

The effect of chemotherapy on survival in patients with nonmetastatic male breast cancer: A population-based observational study.

Male breast cancer is a rare malignant disease, accounting for <1% of all breast cancers. The treatment of male breast cancer is mainly extrapolated from the enormous literature and clinical experience in women. The objective of the current study was to assess the relationship between adjuvant chemotherapy and survival in a large population-based cohort of patients with early-stage male breast cancer. Men with invasive stage I to stage III breast cancer were identified in the Surveillance, Epidemiology, and End Results cancer database from 1990 to 2014. The effect of chemotherapy on survival was determined using multivariable Cox regression. Of 2713 male patients enrolled, 1817 (66.9%) did not receive chemotherapy. Age, T classification, N classification, tumor grade, and progesterone receptor (PR) status were found to be strong predictors of chemotherapy administration. Chemotherapy was associated with a significant 26% reduction in all-cause mortality (P<.001) and a marginally significant 21% reduction in breast cancer-specific mortality (P=.085). For men with PR-negative breast cancer, use of chemotherapy was associated with improved breast cancer-specific survival (hazards ratio [HR], 0.50; 95% confidence interval [95% CI], 0.28-0.91 [P=.023]) and overall survival (HR, 0.54; 95% CI, 0.37-0.77 [P=.001]). However, chemotherapy did not improve the breast cancer-specific survival for all men with PR-positive tumors (P=.959); it was associated with improved overall survival (HR, 0.78; 95% CI, 0.66-0.92 [P=.004]) for men with PR-positive stage II and stage III breast cancer. Chemotherapy should be considered for men with PR-negative, nonmetastatic breast cancer and PR-positive, stage II and stage III breast cancer.

Racial differences in estrogen receptor staining levels and implications for treatment and survival among estrogen receptor positive, HER2-negative invasive breast cancers.

African American women (AAW) die more frequently from estrogen receptor (ER) positive breast cancer than European American women (EAW). We investigated the relationship between race, percent ER staining, treatment, and clinical outcomes. Percent ER staining (weakly ER+: 1-10%, moderately ER+: 11-50%, strongly ER+: > 50%) was abstracted from pathology reports for 1573 women with ER+/HER2- invasive breast cancer treated at a single cancer center in Detroit, MI from 2010 to 2017. Clinical outcomes and tumor characteristics were obtained from the Metropolitan Detroit Cancer Surveillance System. Associations of ER levels with demographic and clinical characteristics were evaluated using logistic regression. Overall and breast cancer-specific (BCS) survival were evaluated using Cox proportional hazards models. AAW were more likely to have tumors with lower ER staining levels than EAW (weakly ER+: Odds ratio (OR) 2.19, p = 0.019; moderately ER+: OR 2.80, p = 0.005). Women with weakly compared to strongly ER+ tumors were less likely to receive endocrine therapy (ET) regardless of race (OR 0.79, p < 0.001). Mortality was predicted by both AA race (Overall hazard ratio (HR) = 1.72, p < 0.001; BCS HR 1.45, p = 0.08) and low (1-50%) ER (Overall HR 1.57, p = 0.083; BCS HR 2.11, p = 0.017) adjusting for clinic-pathologic characteristics. ET was associated with improved BCS survival in all women (1-50%: HR 0.11, p < 0.001; > 50%: HR 0.24, p < 0.001). The biology of ER+/HER2- tumors varies by race, although this does not appear to account for racial differences in survival. Although ET substantially reduces mortality among women with weakly ER+ tumors, these women are less likely to be treated with ET and have poorer outcomes.

BRCA1 Promoter Methylation Status in 1031 Primary Breast Cancers Predicts Favorable Outcomes Following Chemotherapy.

BackgroundBreast Cancer 1 gene (BRCA1) is known to be inactivated in breast tumors by promoter methylation. Tumor cells in patients carrying a germline mutation in BRCA1 are sensitive to cytotoxic drugs that cause DNA double strand breaks. However, very little is known on whether patients with BRCA1 promoter methylated tumors are similarly sensitive to cytotoxic drugs. In this study, we address this by making use of extensive follow-up data on patients treated with cyclophosphamide, methotrexate, and fluorouracil in Iceland between 1976 and 2007.MethodsWe analyzed BRCA1 promoter methylation by pyrosequencing DNA from tumor samples from 1031 patients with primary breast cancer. Of those, 965 were sporadic cases, 61 were BRCA2, and five were BRCA1 germline mutation carriers. All cases were examined with respect to clinicopathological parameters and breast cancer–specific survival in patients treated with cytotoxic drugs. Information on chemotherapy treatment in noncarriers was available for 26 BRCA1 methylated tumors and 857 unmethylated tumors.Results BRCA1 was promoter methylated in 29 sporadic tumors or in 3.0% of cases (29 of 965), whereas none of the tumors derived from BRCA germline mutation carriers were promoter methylated. Important to note, patients with BRCA1 promoter methylation receiving chemotherapeutic drug treatment show highly improved breast cancer–specific survival compared with unmethylated controls (hazard ratio = 0.10, 95% confidence interval = 0.01 to 0.75, two-sided P = .02).Conclusions BRCA1 promoter methylation is predictive of improved disease outcome in patients receiving cyclophosphamide, methotrexate, and fluorouracil drug treatment. Our results support the use of markers indicative of “BRCAness” in sporadic breast cancers to identify patients that are likely to benefit from the use of DNA-damaging agents.

Breast cancer prevention in high-risk women.

Women at high risk of developing breast cancer are a heterogeneous group of women including those with and without high-risk germline mutation/s. Prevention in these women requires a personalised and multidisciplinary approach. Preventive therapy with selective oestrogen receptor modulators (SERMs) like tamoxifen and aromatase inhibitors (AIs) substantially reduces breast cancer risk well beyond the active treatment period. The importance of benign breast disease as a marker of increased breast cancer risk remains underappreciated, and although the benefit of preventive therapy may be greater in such women, preventive therapy remains underutilised in these and other high-risk women. Bilateral Risk-Reducing Mastectomy (BRRM) reduces the risk of developing breast cancer by 90% in high-risk women such as carriers of BRCA mutations. It also improves breast cancer-specific survival in BRCA1 carriers. Bilateral risk-reducing salpingo-oophorectomy may also reduce risk in premenopausal BRCA2 carriers. Further research to improve risk models, to identify surrogate biomarkers of preventive therapy benefit and to develop newer preventive agents is needed.

Adjuvant Chemotherapy for Breast Cancer in Older Women: An Analysis of Retrospective English Cancer Registration Data

AimsAdjuvant chemotherapy is recommended as a treatment for women with high recurrence risk early breast cancer. Older women are less likely to receive chemotherapy than younger women. This study investigated the impact of chemotherapy on breast cancer-specific survival in women aged 70 + years using English registry data. Materials and methodsCancer registration data were obtained from two English regions from 2002 to 2012 (n = 29 728). The impact of patient-level characteristics on the probability of receiving adjuvant chemotherapy was explored using logistic regression. Survival modelling was undertaken to show the effect of chemotherapy and age/health status on breast cancer-specific survival. Missing data were handled using multiple imputation. ResultsIn total, 11 735 surgically treated early breast cancer patients were identified. Use of adjuvant chemotherapy has increased over time. Younger age at diagnosis, increased nodal involvement, tumour size and grade, oestrogen receptor-negative or human epidermal growth factor receptor 2-positive disease were all associated with increased probability of receiving chemotherapy. Chemotherapy was associated with a significant reduction in the hazard of breast cancer-specific mortality in women with high risk cancer, after adjusting for patient-level characteristics (hazard ratio 0.74, 95% confidence interval 0.67–0.81). DiscussionChemotherapy is associated with an improved breast cancer-specific survival in older women with early breast cancer at high risk of recurrence . Lower rates of chemotherapy use in older women may, therefore, contribute to inferior cancer outcomes. Decisions on potential benefits for individual patients should be made on the basis of life expectancy, treatment tolerance and patient preference.

Abstract P1-09-10: Molecular and genetic characterisation of contralateral breast cancers in Northern Ireland: Opportunities for personalised surgery

Abstract Contralateral breast cancer (CBC) incidence is reported as 0.4-0.7% per year, equating to an approximate 10-15% 20 year risk after primary cancer diagnosis. Young age at primary diagnosis and a strong family history are consistently cited as significant risk factors for CBC development. Requests for contralateral prophylactic mastectomy (CPM) are rising, despite a lack of evidence that CPM significantly improves breast cancer specific survival. Therefore, a method to stratify CBC prognosis and risk at an individual level is required to allow us to personalise surgical decision-making for individual patients. This study aims to: 1. Explore prognostic factors following CBC diagnosis; 2. Investigate metastatic CBC prevalence by determining clonal relationships between primary and CBC tumours; 3. Assess the rate of germline predisposition gene mutations in a large cohort of Northern Irish CBC cases. A cohort of 403 CBC patients and 1:1 matched unilateral breast cancer controls (matched for age, year of diagnosis, nodal positivity and tumour morphology) were identified from the Northern Ireland Cancer Registry. Archival primary, CBC and normal lymph node tissue from these CBC patients were obtained for somatic and germline sequencing of a custom 94-gene panel, comprising genes most commonly mutated in breast cancer and all known predisposition genes. CBC patients had a significantly increased risk of breast cancer specific mortality when compared with 1:1 matched unilateral breast cancer controls (HR 6.45, CI 4.27-9.77). Within the CBC cohort, a shorter time interval between primary and CBC diagnosis is associated with increased breast cancer mortality, whereby women with &amp;lt;5 years between diagnoses have the poorest survival (p=0.001). In terms of receptor status, the PR status of ER positive primary and CBC tumours differed significantly (p&amp;lt;0.001). 89.1% of ER positive primary tumours were PR positive, whilst PR positivity was only 54.4% in ER positive CBCs. Indeed, 36.6% of patients with an ER+/PR+ primary BC developed an ER+/PR- CBC, after exposure to anti-oestrogen therapy. Targeted next generation sequencing of 42 cases to date has provided evidence of shared somatic mutations suggestive of metastatic clonality between primary and CBC in four cases (9.5%). Germline pathogenic predisposition gene mutations were identified in five (11.9%) patients and a further ten (23.8%) patients were noted to have germline predisposition variants of unknown significance. Breast cancer specific mortality risk was significantly higher in CBC patients compared with matched unilateral cancer controls, in excess of what would be expected from two primary cancer events. This finding suggests that there are as yet unquantified factors contributing to this excess hazard. Poorer outcome with shorter inter-tumour diagnostic intervals, in addition to evidence of primary-CBC clonality in some cases, suggests that metastatic CBC may play a role in excess risk. Additionally, the significant reduction in PR positivity of ER positive CBC tumours after ER+/PR+ primary tumours, could suggest that acquired hormonal resistance following primary anti-oestrogen therapy exposure may contribute to this additional mortality hazard. Citation Format: McIlmunn CG, Bannon FJ, Fitzpatrick D, Ervine A, Boyd C, Cameron I, Harita T, James J, Gonzalez de Castro D, Savage KI, McIntosh SA. Molecular and genetic characterisation of contralateral breast cancers in Northern Ireland: Opportunities for personalised surgery [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-09-10.

TIM-3 expression in breast cancer

ABSTRACT Tumor-infiltrating lymphocytes (TILs) are predominantly present in breast cancer patients with estrogen receptor negative tumors, among whom increasing levels correlate with favorable outcomes. Nevertheless, currently available immune checkpoint inhibitors appear to benefit only a small number of women with breast cancer. Upregulation of additional immune checkpoint markers is one mechanism of resistance to current inhibitors that might be amenable to targeting with newer agents. T-cell Immunoglobulin and Mucin domain-containing molecule 3 (TIM-3) is an immune checkpoint receptor that is an emerging target for cancer immunotherapy. We investigated TIM-3 immunohistochemical expression in 3,992 breast cancer specimens assembled into tissue microarrays, linked to detailed outcome, clinico-pathological parameters and biomarkers including CD8, PD-1, PD-L1 and LAG-3. We scored and reported absolute counts for TIM-3+ intra-epithelial and stromal TILs (iTILs and sTILs), and find that breast cancer patients with TIM-3+ iTILs (≥ 1) represent a minority of cases (11%), with a predilection for basal-like breast cancers (among which 28% had TIM-3+ iTILs). TIM-3+ sTILs (≥ 2) represented 20% of cases and included more non-basal cases. The presence of TIM-3+ iTILs highly correlates with hematoxylin and eosin-stained stromal TILs and with other immune checkpoint markers (PD-1+ iTILs, LAG-3+ iTILs and PD-L1+ tumors). In prognostic analyses, early breast cancer patients with TIM-3+ iTILs have significantly improved breast cancer-specific survival whereas TIM-3+ sTILs did not reach statistical significance. In multivariate analyses, the presence of TIM-3+ iTILs is an independent favorable prognostic factor in the whole cohort as well as among ER negative patients. Our study supports TIM-3 as a target for breast cancer immunotherapy.

Adjuvant Radiation Therapy for T3N0 Breast Cancer Patients Older Than 75 Years After Mastectomy: A SEER Analysis

IntroductionBreast cancer patients with tumors > 5 cm but without nodal disease who undergo mastectomy present a clinical challenge regarding the appropriate adjuvant treatment. Traditionally, postmastectomy radiation therapy (PMRT) was the standard of care. However, recent studies have suggested local failure rates without PMRT might be low enough to omit RT. This might be especially true in the elderly. Patients and MethodsWomen aged ≥ 75 years with a diagnosis of T3N0 breast cancer who had undergone mastectomy were identified from the Surveillance, Epidemiology, and End Results (SEER) 18 database. The study period was limited to 2006 to 2009 for more modern sampling. Multivariable proportional hazards modeling was used to examine the association of treatment and mortality, adjusting for demographic and clinicopathologic factors. ResultsA total of 635 patients were identified. The median follow-up period was 43 months. PMRT was given to 31.2% of the patients aged 75 to 79 years, 21.5% of those aged 80 to 84 years, and 11.7% of the patients aged ≥ 85 years (P < .001). The receipt of PMRT showed a trend toward improved overall survival on bivariable analysis (hazard ratio [HR], 0.58; P < .001) and multivariable analysis (HR, 0.78; P = .14). The 5-year overall survival was 64.2% for those who had received PMRT and 44.8% for those who had not. A nonsignificant trend was seen toward improved breast cancer-specific survival at 5 years on bivariable analysis (HR, 0.63; P = .09) but not on multivariable analysis. The interaction of age and PMRT receipt could have confounded the results. Patient age and tumor grade were significant indicators of the survival prognosis in these patients. ConclusionThe results of the present analysis of the SEER database suggest that PMRT might still be beneficial in women aged > 75 years with T3N0 disease but also supports continuing efforts to confirm whether it could be safe to omit. It is likely that efforts to subdivide this population using other factors (eg, comorbidity) will be important. The search for refined inclusion and exclusion criteria for adjuvant RT remains an important field of research both clinically and economically.

Bisphosphonate Use and Risk of Recurrence, Second Primary Breast Cancer, and Breast Cancer Mortality in a Population-Based Cohort of Breast Cancer Patients.

Background: Studies of bisphosphonate use and breast cancer recurrence have produced conflicting results. Analyses of large adjuvant trials suggest that bisphosphonates reduce recurrence risk only in postmenopausal women.Methods: We assessed the effect of noncancer treatment-related bisphosphonate use on breast cancer outcomes in a population-based prognostic cohort of women with early-stage invasive breast cancer (n = 1,813; median follow-up = 11.8 years). Using medical record, interview, and cancer registry data, information was assembled on risk factors, cancer treatment, medication use, and outcomes. Statistical analyses used Cox proportional hazards regression models.Results: Bisphosphonate use was associated with a significantly decreased risk of a breast cancer event [locoregional/distant recurrence or second primary breast cancer; HR ever use, 0.65; 95% confidence interval (CI), 0.47-0.90]. Reduced risks were observed in both pre/peri and postmenopausal women, in both ER-negative and ER-positive breast cancers, and for both earlier and later recurrences. Bisphosphonate use was also associated with a significantly decreased risk of breast cancer mortality (HR, 0.40; 95% CI, 0.23-0.69).Conclusions: Bisphosphonate use was associated with a reduction in risk of breast cancer events and improved breast cancer-specific survival in women with early-stage breast cancer. We hypothesize that the benefit of bisphosphonates on breast cancer outcomes may be present primarily in women with low bone density and regardless of menopausal status.Impact: Our findings suggest further consideration of bone density status as a modifier of bisphosphonate's potential beneficial benefits on breast cancer outcomes is warranted. Cancer Epidemiol Biomarkers Prev; 27(2); 165-73. ©2017 AACR.

High nuclear MSK1 is associated with longer survival in breast cancer patients

PurposeMitogen- and stress-activated kinases (MSKs) are important substrates of the mitogen-activated protein kinase (MAPK)-activated protein kinase family. MSK1 and MSK2 are both nuclear serine/threonine protein kinases, with MSK1 being suggested to potentially play a role in breast cancer cell proliferation, cell cycle progression, cell migration, invasion and tumour growth. The aim of the current study was to assess MSK1 protein expression in breast cancer tumour specimens, evaluating its prognostic significance.MethodsA large cohort of 1902 early stage invasive breast cancer patients was used to explore the expression of MSK1. Protein expression was examined using standard immunohistochemistry on tissue microarrays.ResultsLow MSK1 protein expression was associated with younger age (P = 0.004), higher tumour grade (P < 0.001), higher Nottingham Prognostic Index scores (P = 0.007), negative ER (P < 0.001) and PR (P < 0.001) status, and with triple-negative (P < 0.001) and basal-like (P < 0.001) phenotypes. Low MSK1 protein expression was significantly associated with shorter time to distant metastasis (P < 0.001), and recurrence (P = 0.013) and early death due to breast cancer (P = 0.01). This association between high MSK1 expression and improved breast cancer-specific survival was observed in the whole cohort (P = 0.009) and in the HER2-negative and non-basal like tumours (P = 0.006 and P = 0.024, respectively). Multivariate analysis including other prognostic variables indicated that MSK1 is not an independent marker of outcome.ConclusionsHigh MSK1 is associated with improved breast cancer-specific survival in early stage invasive breast cancer patients, and has additional prognostic value in HER2-negative and non-basal like disease. Although not an independent marker of outcome, we believe such findings and significant associations with well-established negative prognostic factors (age, grade, Nottingham Prognostic Index, hormone receptor status, time to distant metastasis, recurrence and triple-negative/basal-like status) warrant further examination and validation in independent patient cohorts.

LAG-3+ tumor infiltrating lymphocytes in breast cancer: clinical correlates and association with PD-1/PD-L1+ tumors

BackgroundNovel immune checkpoint blockade strategies are being evaluated in clinical trials and include targeting the lymphocyte activation gene 3 (LAG-3) checkpoint, alone or in combination with PD-1/PD-L1 blockade. We investigated LAG-3 expression and its prognostic value in a large series of breast cancer patients, and correlated LAG-3 expression with key biomarkers including PD-1 and PD-L1. Experimental designLAG-3 expression was evaluated by immunohistochemistry on two tissue microarray series incorporating 4322 breast cancer primary excision specimens (N = 330 in the training and N = 3992 in the validation set) linked to detailed clinicopathologic, biomarker and long-term clinical outcome data. PD-1 and PD-L1 expressions were also evaluated by immunohistochemistry. Stromal or intra-epithelial tumor infiltrating lymphocytes (sTILs or iTILs) expressing LAG-3 or PD-1 were assessed by absolute count. PD-L1 expression was evaluated as the percentage of positive carcinoma cells per core. Kaplan–Meier curves and Cox proportional hazard models were used for survival analyses. ResultsAfter locking down interpretation cut-offs on the training set, LAG-3+ iTILs were found in 11% of cases in the validation set. In both sets, LAG-3+ iTILs were significantly associated with negative prognostic factors: young age, large tumor size, high proliferation, HER2E and basal-like breast cancer subtypes. In multivariate analyses, breast cancer patients with LAG-3+ iTILs had a significantly improved breast cancer-specific survival [hazard ratio (HR): 0.71, 95% CI 0.56–0.90], particularly among estrogen receptor-negative patients (HR: 0.50, 95% CI 0.36–0.69). Furthermore, we found that 53% of PD-L1+ and 61% of PD-1+ cases were also positive for LAG-3+ iTILs. Concurrent infiltration of LAG-3+ and CD8+ iTILs was significantly associated with increased breast cancer-specific survival (HR: 0.49, 95% CI 0.32–0.74). ConclusionLAG-3+ iTILs are enriched in estrogen receptor-negative breast cancers and represent an independent favorable prognostic factor. In addition, a high proportion of PD-1/PD-L1+ tumors are co-infiltrated with LAG-3+ TILs, supporting potential immune checkpoint blockade combination strategies as a treatment option for breast cancer patients.

Abstract A05: Androgen receptor expression and breast cancer survival in the Nurses' Health Study cohorts

Abstract Background: Sex steroid hormone signaling is critical in the progression of breast cancers, though the role of androgens remains largely unspecified. Evidence from cancer cell line models suggests that androgen receptor (AR) signaling inhibits cell proliferation in estrogen receptor positive (ER+) cancers and stimulates growth of ER- tumors. This hypothesis is supported by population-based studies of ER+ cancers, however the effect of AR in ER- cancers remains unclear, as population studies have had limited sample sizes and short durations of follow-up. Methods: We evaluated the association between AR expression and breast cancer survival among 4,792 pre- and post-menopausal women with invasive breast cancer in the Nurses' Health Study (NHS) and Nurses' Health Study II (NHSII) cohorts. The NHS and NHSII were established in 1976 and 1989, respectively, with the enrollment of U.S. registered nurses between the ages of 30 and 55 (NHS) or 25 and 42 (NHSII). Tumor tissue was obtained from breast cancer cases diagnosed between 1976 and 2006 (NHS) or 1989 and 2006 (NHSII). Tissue microarrays were constructed containing tumor tissue and AR and ER expression were measured by immunohistochemistry and scored manually by pathologists with ≥1% expression considered positive for AR and ER. The association between AR expression and survival was assessed through construction of Kaplan-Meier survival curves and through use of Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals adjusted for patient, tumor, and treatment covariates. Results: Over follow-up through 2014 (median 15.3 years), a total of 1,666 deaths and 813 deaths due to breast cancer occurred. We observed that AR expression was associated with improved breast cancer-specific survival overall (p&amp;lt;0.001 from log-rank test) and among ER+ tumors (p&amp;lt;0.001), while there was a non-significant deleterious effect of AR expression among ER- tumors (p=0.076). These findings were robust in Cox proportional hazards models that accounted for patient, tumor, and treatment covariates. Overall, AR expression was associated with a 16% reduction in the breast cancer-specific mortality rate (HR=0.84, 95% CI 0.70-1.01). This association was more prominent among ER+ tumors, where breast cancer mortality was 31% lower for women who co-expressed AR (HR=0.69, 95% CI 0.55-0.88). In contrast, AR expression led to a 33% increase in breast cancer mortality among ER- tumors (HR=1.33, 95% CI 1.01-1.75), and a 44% increase in the subset of triple negative ER-/PR-/HER2- tumors (HR=1.44, 95% CI 1.01-2.07). Similar associations were observed when evaluating the outcome of overall survival and when using an alternative cut point of 10% for AR expression. We found no significant interactions between AR expression and treatment covariates. Conclusions: AR expression was found to be a robust predictor of breast cancer survival with the direction of the association dependent on tumor ER co-expression. These findings support the hypothesis that AR signaling pathways may be potential therapeutic targets using AR signaling agonists for ER+ cancers and AR signaling antagonists for ER- cancers. Citation Format: Kevin H. Kensler, Elizabeth M. Poole, Laura C. Collins, Andrew H. Beck, Bernard A. Rosner, A. Heather Eliassen, Susan E. Hankinson, Myles Brown, Rulla M. Tamimi. Androgen receptor expression and breast cancer survival in the Nurses' Health Study cohorts [abstract]. In: Proceedings of the AACR International Conference: New Frontiers in Cancer Research; 2017 Jan 18-22; Cape Town, South Africa. Philadelphia (PA): AACR; Cancer Res 2017;77(22 Suppl):Abstract nr A05.

The calpain system is associated with survival of breast cancer patients with large but operable inflammatory and non-inflammatory tumours treated with neoadjuvant chemotherapy.

The calpains are a family of intracellular cysteine proteases that function in a variety of important cellular functions, including cell signalling, motility, apoptosis and survival. In early invasive breast cancer expression of calpain-1, calpain-2 and their inhibitor, calpastatin, have been associated with clinical outcome and clinicopathological factors.The expression of calpain-1, calpain-2 and calpastatin was determined using immunohistochemistry on core biopsy samples, in a cohort of large but operable inflammatory and non-inflammatory primary breast cancer patients treated with neoadjuvant chemotherapy. Information on treatment and prognostic variables together with long-term clinical follow-up was available for these patients. Diagnostic pre-chemotherapy core biopsy samples and surgically excised specimens were available for analysis.Expression of calpastatin, calpain-1 or calpain-2 in the core biopsies was not associated with breast cancer specific survival in the total patient cohort; however, in patients with non-inflammatory breast cancer, high calpastatin expression was significantly associated with adverse breast cancer-specific survival (P=0.035), as was low calpain-2 expression (P=0.031). Low calpastatin expression was significantly associated with adverse breast cancer-specific survival of the inflammatory breast cancer patients (P=0.020), as was low calpain-1 expression (P=0.003).In conclusion, high calpain-2 and low calpastatin expression is associated with improved breast cancer-specific survival in non-inflammatory large but operable primary breast cancer treated with neoadjuvant chemotherapy. In inflammatory cases, high calpain-1 and high calpastatin expression is associated with improved breast cancer-specific survival. Determining the expression of these proteins may be of clinical relevance. Further validation, in multi-centre cohorts of breast cancer patients treated with neoadjuvant chemotherapy, is warranted.

The prognostic significance of STAT3 in invasive breast cancer: analysis of protein and mRNA expressions in large cohorts.

Signal transducer and activator of transcription (STAT) transcription factors family are involved in diverse cellular biological functions. Reports regarding the prognostic impact of STAT3 expression in breast cancer (BC) are variable whether being a factor of poor or good prognosis. Immunohistochemical expression of phospho-STAT3 (pSTAT3) was studied in large series of invasive BC (n = 1270). pSTAT3 and STAT3 were quantified using reverse phase protein array (RPPA) on proteins extracted from macro-dissected FFPE tissues (n = 49 cases). STAT3 gene expression in the METABRIC cohort was also investigated. STAT3 gene expression prognostic impact was externally validated using the online BC gene expression data (n = 26 datasets, 4.177 patients). pSTAT3 was expressed in the nuclei and cytoplasm of invasive BC cells. Nuclear pSTAT3 overexpression was positively associated with smaller tumour size, lower grade, good NPI, negative lymphovascular invasion (LVI), ER+, PgR+, p53-, HER2-, and low Ki67LI and an improved breast cancer-specific survival (BCSS), independently of other factors. On RPPA, the mean pSTAT3 and STAT3 expressions were higher in ER+, PgR+, and smaller size tumours. Higher STAT3 transcripts in the METABRIC cohort were observed in cases with favourable prognostic criteria and as well as improved BCSS within the whole cohort, ER+ cohort with and without hormonal therapy, and ER- cohort including those who did not receive adjuvant chemotherapy. Pooled STAT3 gene expression data in the external validation cohort showed an association with improved patients' outcome (P < 0.001, HR = 0.84, 95 % CI 0.79-0.90). Results of this study suggest nuclear localisation of pSTAT3 as favourable prognostic marker in invasive BC, results re-enforced by analysis of STAT3 gene expression data. This good prognostic advantage was maintained in patients who received and who did not receive adjuvant therapy. Therefore, STAT3 could have context-dependent molecular roles of in BC, results which warrant further prospective verification in clinical trials.

Combined evaluation of LC3B puncta and HMGB1 expression predicts residual risk of relapse after adjuvant chemotherapy in breast cancer

In spite of adjuvant chemotherapy, a significant fraction of patients with localized breast cancer (BC) relapse after optimal treatment. We determined the occurrence of cytoplasmic MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3B)-positive puncta, as well as the presence of nuclear HMGB1 (high mobility group box 1) in cancer cells within surgical BC specimens by immunohistochemistry, first in a test cohort (152 patients) and then in a validation cohort of localized BC patients who all received adjuvant anthracycline-based chemotherapy (1646 patients). Cytoplasmic LC3B+ puncta inversely correlated with the intensity of SQSTM1 staining, suggesting that a high percentage cells of LC3B+ puncta reflects increased autophagic flux. After setting optimal thresholds in the test cohort, cytoplasmic LC3B+ puncta and nuclear HMGB1 were scored as positive in 27.2% and 28.6% of the tumors, respectively, in the validation cohort, while 8.7% were considered as double positive. LC3B+ puncta or HMGB1 expression alone did not constitute independent prognostic factors for metastasis-free survival (MFS) in multivariate analyses. However, the combined positivity for LC3B+ puncta and nuclear HMGB1 constituted an independent prognostic factor significantly associated with prolonged MFS (hazard ratio: 0.49 95% confidence interval [0.26–0.89]; P = 0.02), and improved breast cancer specific survival (hazard ratio: 0.21 95% confidence interval [0.05–0.85]; P = 0.029). Subgroup analyses revealed that within patients with poor-prognosis BC, HMGB1+ LC3B+ double-positive tumors had a better prognosis than BC that lacked one or both of these markers. Altogether, these results suggest that the combined positivity for LC3B+ puncta and nuclear HMGB1 is a positive predictor for longer BC survival.

Timing of Postmastectomy Reconstruction Does Not Impair Breast Cancer-Specific Survival: A Population-Based Study

BackgroundDebate remains over the optimal timing of breast reconstruction after mastectomy. Immediate reconstruction has demonstrated superior psychosocial and aesthetic outcomes, but might delay adjuvant therapy. Conversely, delayed reconstruction allows for timely initiation of adjuvant therapy, but with potentially inferior aesthetic results. The authors examined whether any significant breast cancer-specific survival difference exists on the basis of the timing of reconstruction after mastectomy. Patients and MethodsUsing a cancer registry, medical insurance, and vital statistics sources, all Nova Scotia women who underwent unilateral mastectomy for breast cancer between 1989 and 2007 were followed to 2012 or time of death. Breast cancer-specific survival was compared for mastectomy patients who did or did not undergo reconstruction. Cox proportional hazards models were fitted adjusting for known demographic, disease severity variables, comorbidities, and reconstruction timing. ResultsOf 6790 subjects included in the study, 331 (4.9%) underwent breast reconstruction. Of those who underwent reconstruction, 209 (63%) and 122 (37%) underwent immediate and delayed reconstruction, respectively. Univariate analysis showed improved breast cancer-specific survival among all breast reconstruction patients compared with patients who underwent mastectomy alone (hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.48-0.86). In a multivariate model fitting a time-varying covariate to adjust for timing of reconstruction from mastectomy, no difference in survival was observed between patients who underwent reconstruction at any time and those who underwent mastectomy only (HR, 0.75; 95% CI, 0.56-1.00). No differences in breast cancer-specific survival were observed on the basis of type of reconstruction. ConclusionResults of the current study suggest that breast reconstruction, regardless of its timing, carries no increased risk of breast cancer-specific mortality compared with mastectomy alone.