Impacts of smoking on endocrine treatment response in a prospective breast cancer cohort

Pre- and Postoperative Antioxidant Use, Aryl Hydrocarbon Receptor (AhR) Activation and Clinical Outcome in Different Treatment Groups of Breast Cancer Patients

BACKGROUND

Cancer patients often use antioxidants that may interact with adjuvant treatments. The purpose was to investigate pre- and postoperative antioxidant use in relation to clinicopathological characteristics and prognosis in different breast cancer treatment groups.

METHODS AND PATIENTS

Pre- and postoperative antioxidant (vitamin A, C, E, carotenoids, or Q10) or multivitamin use was self-reported by patients from Lund (n = 1855) and Helsingborg (n=478), Sweden. Patients were followed for up to 15 years. Clinical data were obtained from patient charts. The aryl hydrocarbon receptor (AhR) was evaluated in tumor tissue arrays from 915 patients from Lund and with Western blot in MCF-7 and MDA-MB-231 cells.

RESULTS

About 10% of patients used antioxidants. Nuclear AhR (AhRnuc) positivity was twice as common in preoperative antioxidant users compared to non-users. In mechanistic studies vitamin C increased AhR levels and its downstream target CYP1B1, indicating AhR activation. There were significant interactions between tumor AhRnuc status and preoperative antioxidant use in relation to clinical outcome. In all patients, antioxidant use (other than multivitamins) at both visits was associated with poorer prognosis, while use only at the follow-up visit was associated with better prognosis, compared with no use at either visit.

CONCLUSION

The clinical impact of antioxidants depended on antioxidant type, timing of use, and tumor AhR activation. Antioxidants may influence clinical outcome by activation of the master regulator AhR in addition to interference with free radicals. Further studies are needed to identify breast patients that might improve or worsen their prognosis when using antioxidants postoperatively.

The Vitamin D Receptor as a Prognostic Marker in Breast Cancer-A Cohort Study

Previous research has indicated an association between the presence of the vitamin D receptor (VDR) in breast cancer tissue and a favorable prognosis. This study aimed to further evaluate the prognostic potential of VDR located in the nuclear membrane or nucleus (liganded). The VDR protein levels were analyzed using immunohistochemistry in tumor samples from 878 breast cancer patients from Lund, Sweden, included in the Breast Cancer and Blood Study (BCBlood) from October 2002 to June 2012. The follow-up for breast cancer events and overall survival was recorded until 30 June 2019. Univariable and multivariable survival analyses were conducted, both with complete case data and with missing data imputed using multiple imputation by chained equations (MICE). Tumor-specific positive nuclear membrane VDR(num) staining was associated with favorable tumor characteristics and a longer breast cancer free interval (BCFI; HR: 0.64; 95% CI: 0.44-0.95) and overall survival (OS; HR: 0.52; 95% CI: 0.34-0.78). Further analyses indicated that VDRnum status also was predictive of overall survival when investigated in relation to ER status. There were significant interactions between VDR and invasive tumor size (Pinteraction = 0.047), as well as mode of detection (Pinteraction = 0.049). VDRnum was associated with a longer BCFI in patients with larger tumors (HR: 0.36; 95% CI: 0.14-0.93) or clinically detected tumors (HR: 0.28; 95% CI: 0.09-0.83), while no association was found for smaller tumors and screening-detected tumors. Further studies are suggested to confirm our results and to evaluate whether VDR should and could be used as a prognostic and targetable marker in breast cancer diagnostics.

Caveolin-1 genotypes as predictor for locoregional recurrence and contralateral disease in breast cancer

PURPOSE

Caveolin-1 (CAV1) has been implicated in breast cancer oncogenesis and metastasis and may be a potential prognosticator, especially for non-distant events. CAV1 functions as a master regulator of membrane transport and cell signaling. Several CAV1 SNPs have been linked to multiple cancers, but the prognostic impact of CAV1 SNPs in breast cancer remains unclear. Here, we investigated CAV1 polymorphisms in relation to clinical outcomes in breast cancer.

METHODS

A cohort of 1017 breast cancer patients (inclusion 2002-2012, Sweden) were genotyped using Oncoarray by Ilumina. Patients were followed for up to 15 years. Five out of six CAV1 SNPs (rs10256914, rs959173, rs3807989, rs3815412, and rs8713) passed quality control and were used for haplotype construction. CAV1 genotypes and haplotypes in relation to clinical outcomes were assessed with Cox regression and adjusted for potential confounders (age, tumor characteristics, and adjuvant treatments).

RESULTS

Only one SNP was associated with lymph node status, no other SNPs or haplotypes were associated with tumor characteristics. The CAV1 rs3815412 CC genotype (5.8% of patients) was associated with increased risk of contralateral breast cancer, adjusted hazard ratio (HR_adj) 4.26 (95% CI 1.86-9.73). Moreover, the TTACA haplotype (13% of patients) conferred an increased risk for locoregional recurrence HR_adj 2.24 (95% CI 1.24-4.04). No other genotypes or haplotypes were associated with clinical outcome.

CONCLUSION

CAV1 polymorphisms were associated with increased risk for locoregional recurrence and contralateral breast cancer. These findings may identify patients that could derive benefit from more tailored treatment to prevent non-distant events, if confirmed.

Effect of Smoking on Treatment Efficacy and Toxicity in Patients with Cancer: A Systematic Review and Meta-Analysis

Simple Summary

The impact of smoking on cancer treatment efficacy and toxicity regardless of cancer type was investigated in this meta-analysis. Smoking during radiotherapy/chemoradiotherapy was associated with worse outcomes and a higher risk for toxicity. Smoking during treatment with EGFR tyrosine kinase inhibitors in lung cancer patients was associated with a worse prognosis, whereas smoking was associated with better outcomes in patients treated with checkpoint inhibitors. No association between smoking and treatment efficacy of chemotherapy was observed, though with low certainty of evidence. Our results can be used by oncology and radiotherapy staff to give patients more convincing information on the benefits that can be derived from smoking cessation before cancer treatment.

Abstract

Aim: The aim of the present systematic review and meta-analysis was to summarize the current evidence on the potential impact of smoking during cancer treatment on treatment efficacy and toxicity irrespective of cancer type. Methods: A systematic literature search was performed using two electronic databases for potentially eligible studies. Only studies based on multivariable analysis for the association between smoking, compared to non-smokers (never or former), and treatment efficacy or toxicity were included. Pooled Hazard Ratios (HRs) or Odds Ratios (ORs) and corresponding 95% Confidence Intervals (CIs) were estimated through random-effects meta-analyses. Results: In total, 97 eligible studies were identified, of which 79 were eligible for the pooled analyses. Smoking during radiation therapy, with or without chemotherapy, was associated with an increased risk of locoregional recurrence (pooled HR: 1.56; 95% CI: 1.28–1.91 for radiation therapy; pooled HR: 4.28; 95% CI: 2.06–8.90 for chemoradiotherapy) and worse disease-free survival (pooled HR: 1.88; 95% CI: 1.21–2.90 for radiation therapy; pooled HR: 1.92; 95% CI: 1.41–2.62 for chemoradiotherapy) as well as a higher risk for radiation-induced toxicity (pooled OR: 1.84; 95% CI: 1.32–2.56 for radiation therapy; pooled OR: 2.43; 95% CI: 1.43–4.07 for chemoradiotherapy) with low-to-moderate certainty of evidence. Smoking during treatment with EGFR tyrosine kinase inhibitors (EGFR-TKIs) in patients with lung cancer was associated with worse progression-free survival compared to non-smokers (pooled HR: 1.43; 95% CI: 1.14–1.80; moderate certainty of evidence), whereas smoking was associated with improved progression-free survival in patients treated with checkpoint inhibitors (HR: 0.70; 95% CI: 0.58–0.84; moderate certainty of evidence). No statistically significant associations were observed between smoking and treatment efficacy or toxicity to chemotherapy. Conclusion: The present meta-analysis confirms earlier evidence of the negative impact of smoking during radiation therapy, with or without chemotherapy, on treatment efficacy and radiation-induced toxicity as well as a negative impact of smoking on the efficacy of EGFR-TKIs and a positive impact on the efficacy of checkpoint inhibitors. The evidence is too weak to draw firm conclusions on the potential association between smoking and chemotherapy, whereas there is no evidence for pooled analyses regarding other types of systemic oncological therapy.

Interplay between Caveolin-1 and body and tumor size affects clinical outcomes in breast cancer

BACKGROUND

Caveolin-1 (CAV1) is associated with cholesterol-rich membrane raft domains and is a master regulator of cell signaling and membrane transport. Here, we investigated CAV1's role in cellular compartments of breast cancer in relation to signaling pathways, clinicopathological features, and clinical outcomes.

METHODS

CAV1 levels were evaluated with immunohistochemistry in cytoplasm of invasive tumor cells and stromal cells in tumor tissue microarrays from a cohort of 1018 breast cancer patients (inclusion 2002-2012, Sweden). Cytoplasmic and stromal CAV1 were categorized as positive/negative and strong/not strong, respectively. CAV1 expression in relation to clinical outcomes was assessed with Cox regression. Investigations into CAV1 functional pathways was conducted in the STRING, GOBO, and TCGA databases.

RESULTS

CAV1 expression was associated with non-luminal subtypes, cell cycle control, inflammation, epithelial-mesenchymal transition, and the IGF/Insulin system. Generally, CAV1 was not associated with recurrence risk. Stromal CAV1's impact on recurrence risk was modified by BMI ≥25 kg/m² (P_interaction = 0.002), waist ≥80 cm (P_interaction = 0.005), and invasive tumor size (pT2/3/4) (P_interaction = 0.028). In low-risk patients only, strong stromal CAV1 significantly increased recurrence risk (HRs_adj ≥1.61). In all patients, positive cytoplasmic CAV1 conferred >2-fold risk for contralateral disease HR_adj 2.63 (95% CI 1.36-5.10). Strong stromal CAV1 conferred nearly 2-fold risk for locoregional recurrence HR_adj 1.88 (95% CI 1.09-3.24).

CONCLUSIONS

CAV1's prognostic impact depended on its localization, anthropometric, and tumor factors. Stromal CAV1 predicted high recurrence risk in a group of supposedly 'low-risk' patients. Cytoplasmic CAV1 predicted metachronous contralateral disease. If confirmed, CAV1 could be used as treatment target and for risk-stratification.

The Association Between Smoking Status and Breast Cancer Recurrence: A Systematic Review

PURPOSE

To determine whether smoking status (active/passive) affects recurrence events after breast cancer (BC) diagnosis among women.

METHODS

A comprehensive literature search of MEDLINE, Cochrane Central, EMBASE, and Web of Science databases on smoking status and BC outcomes retrieved 5,940 articles. After reviewing the inclusion and exclusion criteria, we selected 14 articles for a full review and synthesis.

RESULTS

Five studies were cohort retrospective, 6 were case-control, 2 were prospective cohort studies, and 1 was a secondary analysis of a randomized control trial. Among the 8 articles that focused on active smoking, 6 showed an increased risk of BC recurrence, and 2 showed no evidence of such an association. Studies that examined former smokers found little evidence of an increased risk of BC recurrence. This association may be dose-dependent.

CONCLUSION

Given the current evidence, although limited, active smokers should quit smoking after BC diagnosis as trends indicate a positive association between active and BC recurrence. More robust evidence is needed to assess such associations and examine the outcomes of quitting smoking in such patients.

Relationship between Cigarette Smoking and Cancer Characteristics and Survival among Breast Cancer Patients

Carcinogenic effects of tobacco smoke may affect breast tumorigenesis. To assess whether cigarette smoking is associated with breast cancer characteristics, we investigated the relationships between smoking, pathological characteristics, and outcomes in 2153 women diagnosed with breast cancer 2001-2016. Patients were classified as never, former, or current smokers at the time of diagnosis. Logistic regression and multivariable Cox proportional hazards analysis were performed to determine whether smoking was associated with tumor characteristics. Multivariable Cox proportional hazards analysis was conducted to compare former or current smokers to never smokers in survival with adjustment for the potential confounders. The majority of women (61.8%) never smoked, followed by former smokers (26.2%) and current smokers (12.0%). After adjustment for demographic variables, body mass index, and comorbidities, tumor characteristics were not significantly associated with smoking status or pack-years smoked. Ten-year overall survival was significantly lower for former and current smokers compared to never smokers (p = 0.0105). However, breast cancer specific survival did not differ significantly between groups (p = 0.1606). Although cigarette smoking did not alter the underlying biology of breast tumors or breast cancer-specific survival, overall survival was significantly worse in smokers, highlighting the importance of smoking cessation in the recently diagnosed breast cancer patient.

The Impact of Treatment for Smoking on Breast Cancer Patients' Survival

BACKGROUND

Smoking negatively affects overall survival after successful breast cancer (BC) treatment. We hypothesized that smoking cessation would improve survival outcomes of BC patients who were smokers at the time of diagnosis.

METHODS

This was a retrospective analysis of self-identified smokers with BC treated at The University of Texas MD Anderson Cancer Center. Patient demographics, date of diagnosis, tumor stage, tobacco treatment program (TP) participation, and time to death were extracted from our departmental databases and institutional electronic health records. We examined associations between tobacco abstinence status and survival using survival models, with and without interactions, adjusted for personal characteristics and biomarkers of disease.

RESULTS

Among all 31,069 BC patients treated at MD Anderson between 2006 and 2017, we identified 2126 smokers (6.8%). From those 2126 self-identified smokers, 665 participated in the TP, reporting a conservative estimate of 31% abstinence (intent-to-treat) 9 months into the program. Patients without reported follow-up abstinence status (including TP and non-TP participants) were handled in the analyses as smokers. Survival analysis controlled for multiple factors, including disease characteristics and participation in the TP, indicated that abstainers were more likely to be alive with no evidence of disease compared to non-abstainers (HR, 0.593; 95% CI, 0.386-0.911; p = 0.017).

CONCLUSION

Our results suggest that quitting smoking is associated with improved survival among BC patients who were smokers at time of diagnosis across all tumor stages. Comprehensive approaches for smoking cessation in patients diagnosed with BC may prolong survival when started as early as the time of diagnosis.

Prognostic impact of tumor-specific insulin-like growth factor binding protein 7 (IGFBP7) levels in breast cancer: a prospective cohort study

The prognostic impact of insulin-like growth factor binding protein 7 (IGFBP7) in breast cancer is unclear. Host factors, including lifestyle, anthropometry and metabolic profile, might influence tumor-specific IGFBP7. This study aimed to investigate whether IGFBP7 levels and messenger ribonucleic acid (mRNA) expression are associated with the patient and tumor characteristics and prognosis in breast cancer. Patients with primary breast cancer in Lund, Sweden, were included preoperatively in the study between 2002 and 2012 (n = 1018). Tumor-specific IGFBP7 protein levels were evaluated with immunohistochemistry using tissue microarrays in tumors from 878 patients. IGFBP7 mRNA expression and its corresponding clinical data were obtained from The Cancer Genome Atlas and analyzed for 809 patients. Tumor-specific IGFBP7 protein levels were categorized based on Histo 300 scores into IGFBP7^low (6.2%), IGFBP7^intermediate (75.7%) and IGFBP7^high (18.1%). Both low IGFBP7 protein levels and mRNA expression were associated with less aggressive tumor characteristics. Overall, IGFBP7^low conferred low recurrence risk. The prognostic impact of IGFBP7^high varied according to any alcohol consumption and tamoxifen treatment. IGFBP7^high was associated with low recurrence risk in alcohol consumers but high recurrence risk in alcohol abstainers (P_interaction= 0.039). Moreover, the combination of IGFBP7^high and estrogen receptor-positive tumors was associated with low recurrence risk only in tamoxifen-treated patients (P_interaction= 0.029). To conclude, IGFBP7^low might be a good, independent prognosticator in breast cancer. The prognostic impact of IGFBP7^high depends on host factors and treatment. IGFBP7 merits further investigation to confirm whether it could be a suitable biomarker for treatment selection.

Smoking Cessation after a Cancer Diagnosis: A Cross-Sectional Analysis in the Setting of a Developing Country

Since smoking accounts for around 30% of all cancer deaths, public health campaigns often focus on smoking cessation as a means of primary prevention. However, smoking after cancer diagnosis is also associated with a higher symptom burden and lower survival rate. As data regarding smoking cessation vary dramatically between different populations, we aimed to analyze smoking prevalence in cancer patients, smoking cessation after cancer diagnosis, and the factors associated with smoking cessation in the setting of a developing country. We performed a cross-sectional survey on 695 patients in two clinical hospital centers. After cancer diagnosis, 15.6% of cancer patients stopped smoking. Male gender, younger age, and smoking-related cancer were the main factors associated with greater smoking cessation (p < 0.05). A total of 96% of breast cancer patients continued to smoke after cancer diagnosis and, compared to lung and colorectal cancer patients, exhibited a lower reduction in the number of cigarettes smoked (p = 0.023). An alarming rate of smoking prevalence was recorded in younger patients (45.6% at the time of cancer diagnosis) suggesting a future rise in smoking-related cancers and complications. These results should guide anti-smoking public health campaigns in transitional countries with a critical focus on younger and breast cancer patients.

The Prognostic Impact of Intratumoral Aryl Hydrocarbon Receptor in Primary Breast Cancer Depends on the Type of Endocrine Therapy: A Population-Based Cohort Study

The aryl hydrocarbon receptor (AhR) is a master regulator of multiple pathways involved in breast cancer, and influences the estrogen receptor alpha (ER) and aromatase/CYP19A1. The purpose of this study was to elucidate the interplay between intratumoral levels of AhR and aromatase, patient characteristics (including AhR and CYP19A1 genotypes), clinicopathological features, and prognosis in breast cancer patients receiving adjuvant treatments. A prospective cohort of 1116 patients with primary breast cancer in Sweden, included 2002-2012, was followed until June 30th 2019 (median 8.7 years). Tumor-specific AhR (n=920) and aromatase levels (n=816) were evaluated on tissue microarrays using immunohistochemistry. Associations between cytoplasmatic (AhRcyt) and nuclear (AhRnuc) AhR levels, intratumoral aromatase, clinicopathological features, and prognosis in different treatment groups were analyzed. Low AhRcyt levels (n=183) and positive intratumoral aromatase (n=69) were associated with estrogen receptor (ER)- status and more aggressive tumors. Genotypes were not associated with their respective protein levels. The functional AhR Arg554Lys GG genotype was associated with recurrence-free survival in switch-therapy (sequential tamoxifen/aromatase inhibitors (AI) or AI/tamoxifen) treated patients (HRadj 0.42; 95% CI 0.22-0.83). High AhRcyt levels were associated with longer recurrence-free survival during the first 10 years of follow-up among tamoxifen-only treated patients (HRadj 0.40; 95% CI 0.23-0.71) compared to low AhRcyt levels, whereas an almost inverse association was seen in patients with switch-therapy (P interaction=0.023). Intratumoral aromatase had little prognostic impact. These findings warrant confirmation in an independent cohort, preferably in a randomized clinical trial comparing different endocrine regimens. They might also guide the selection of breast cancer patients for clinical trials with selective AhR modulators.

CYP27A1 expression is associated with risk of late lethal estrogen receptor-positive breast cancer in postmenopausal patients

Background

27-Hydroxycholesterol (27HC) stimulates estrogen receptor-positive (ER+) breast cancer (BC) progression. Inhibiting the sterol 27-hydroxylase (CYP27A1) abrogates these growth-promoting effects of 27HC in mice. However, the significance of CYP27A1 expression on BC biology and prognosis is unclear.

Methods

Intratumoral CYP27A1 expression in invasive BC was measured by immunohistochemistry in two Swedish population-based cohorts (n = 645 and n = 813, respectively). Cox proportional hazards models were used to evaluate the association between CYP27A1 expression and prognosis.

Results

CYP27A1 was highly expressed in less than 1/3 of the tumors. High CYP27A1 expression was more frequent among high-grade tumors lacking hormone receptor expression and with larger tumor sizes. Over a median of 12.2 years follow-up in cohort 1, high CYP27A1 expression was associated with impaired survival, specifically after 5 years from diagnosis among all patients [overall survival (OS), HR_adjusted = 1.93, 95%CI = 1.26–2.97, P = 0.003; breast cancer-specific survival (BCSS), HR_adjusted = 2.33, 95%CI = 1.28–4.23, P = 0.006] and among patients ≥ 55 years presenting with ER+ tumors [OS, HR_adjusted = 1.99, 95%CI = 1.24–3.21, P = 0.004; BCSS, HR_adjusted = 2.78, 95%CI = 1.41–5.51, P = 0.003].

Among all patients in cohort 2 (median follow-up of 7.0 years), CYP27A1 expression was significantly associated with shorter OS and RFS in univariable analyses across the full follow-up period. However after adjusting for tumor characteristics and treatments, the association with survival after 5 years from diagnosis was non-significant among all patients [OS, HR_adjusted = 1.08, 95%CI = 0.05–2.35, P = 0.83 and RFS, HR_adjusted = 1.22, 95%CI = 0.68–2.18, P = 0.50] as well as among patients ≥ 55 years presenting with ER+ tumors [OS, HR_adjusted = 0.46 95% CI = 0.11–1.98, P = 0.30 and RFS, HR_adjusted = 0.97 95% CI = 0.44–2.10, P = 0.93].

Conclusion

CYP27A1 demonstrated great potentials as a biomarker of aggressive tumor biology and late lethal disease in postmenopausal patients with ER+ BC. Future studies should investigate if the benefits of prolonged endocrine therapy and cholesterol-lowering medication in BC are modified by CYP27A1 expression.

No Impact of Smoking Status on Breast Cancer Tumor Infiltrating Lymphocytes, Response to Neoadjuvant Chemotherapy and Prognosis

Simple Summary

Tobacco use is associated with an increase in breast cancer mortality. Pathologic complete response (pCR) rate to neoadjuvant chemotherapy is influenced by tumor-infiltrating lymphocyte (TIL) levels and is associated with a better long-term survival outcome. The aim of this study was to evaluate the impact of smoking status on TIL levels, response to neoadjuvant chemotherapy and prognosis for breast cancer patients. We retrospectively assessed pre- and post-neoadjuvant chemotherapy tumor infiltrating lymphocyte (TILs) levels and pathological complete response (pCR) rates in a cohort of 956 specimens of breast cancer (BC) patients treated with neoadjuvant chemotherapy, according to their smoking status. To our knowledge, this is the largest cohort of BC patients used to study this topic so far. We found no impact of smoking status on tumor infiltrating lymphocyte levels, response to neoadjuvant chemotherapy and prognosis in the whole population and within each BC subtype.

Abstract

Tobacco use is associated with an increase in breast cancer (BC) mortality. Pathologic complete response (pCR) rate to neoadjuvant chemotherapy (NAC) is influenced by tumor-infiltrating lymphocyte (TIL) levels and is associated with a better long-term survival outcome. The aim of our study is to evaluate the impact of smoking status on TIL levels, response to NAC and prognosis for BC patients. We retrospectively evaluated pre- and post-NAC stromal and intra tumoral TIL levels and pCR rates on a cohort of T1-T3NxM0 BC patients treated with NAC between 2002 and 2012 at Institut Curie. Smoking status (current, ever, never smokers) was collected in clinical records. We analyzed the association between smoking status, TIL levels, pCR rates and survival outcomes among the whole population, and according to BC subtype. Nine hundred and fifty-six BC patients with available smoking status information were included in our analysis (current smokers, n = 179 (18.7%); ever smokers, n = 154 (16.1%) and never smokers, n = 623 (65.2%)). Median pre-NAC TIL levels, pCR rates, or median post-NAC TIL levels were not significantly different according to smoking status, neither in the whole population, nor in any BC subtype group. With a median follow-up of 101.4 months, relapse-free survival (RFS) and overall survival (OS) were not significantly different by smoking status. We did not find any significant effect of tobacco use on pre- and post-NAC TILs nor response to NAC. Though our data seem reassuring, BC treatment should still be considered as a window of opportunity to offer BC patients accurate smoking cessation interventions.

Patient Characteristics Influence Activated Signal Transducer and Activator of Transcription 3 (STAT3) Levels in Primary Breast Cancer-Impact on Prognosis

Background: Activated signal transducer and activator of transcription 3 (pSTAT3) is often present in breast cancer, but its prognostic impact is still unclear. We investigated how breast tumor-specific pSTAT3^Y705 levels are associated with patient and tumor characteristics and risk of recurrence.

Materials and Methods: Primary breast cancer patients without preoperative treatment were included preoperatively. The patients were treated in Lund, Sweden, in 2002–2012 and followed until 2016. Levels of pSTAT3^Y705 were evaluated in 867 tumors using tissue microarrays with immunohistochemistry and categorized according to the H-score as negative (0–9; 24.2%), intermediate (10–150; 69.9%), and high (160–300; 5.9%).

Results: Patients were followed for up to 13 years, and 137 recurrences (88 distant) were recorded. Higher pSTAT3^Y705 levels were associated with patient characteristics including younger age, any alcohol consumption, higher age at first child birth, and smaller body size, as well as tumor characteristics including smaller tumor size, lower histological grade, lymph node negativity, progesterone receptor positivity, and HER2 negativity (all P_trends ≤ 0.04). Higher pSTAT3^Y705 levels were associated with lower risk of early recurrences (LogRank P_trend = 0.10; 5-year LogRank P_trend = 0.004) and distant metastases (LogRank P_trend = 0.045; 5-year LogRank P_trend = 0.0007), but this was not significant in the multivariable models. There was significant effect modification between tamoxifen treatment and pSTAT3^Y705 negativity on the recurrence risk in chemonaïve patients with estrogen receptor positive tumors [adjusted hazard ratio (HR) 0.38; P_interaction = 0.046].

Conclusion: Higher pSTAT3^Y705 levels were associated with several patient and tumor characteristics that are mainly associated with good prognosis and a tendency toward lower risk for early recurrences. In the future, these results may help guide the selection of patients for trials with drugs targeting the STAT3 pathway.

Prognostic Impact of Menopausal Hormone Therapy in Breast Cancer Differs According to Tumor Characteristics and Treatment

This study investigated how a history of menopausal hormone therapy (MHT) impacts clinical outcomes overall and in different subgroups of breast cancer patients. The study included 814 primary breast cancer patients aged ≥50 years in Sweden (2002–2012) with follow-up until 2016. Associations between patient- and tumor characteristics, recurrences, and overall survival were analyzed in relation to MHT. After a median follow-up of 7 years, 119 recurrences, and 111 deaths occurred. Ever MHT (n = 433, 53.2%) was associated with a lower BMI, frequency of alcohol abstinence, and histological grade, higher frequency of oral contraceptive use, and lobular cancer. Overall, MHT was not associated with prognosis, but there were significant effect modifications by estrogen receptor (ER) status, node status, main histological type, and aromatase inhibitor (AI) treatment on recurrence-risk (all P_interactions≤ 0.017). MHT conferred an increased recurrence-risk in patients with ER- tumors, adjusted Hazard Ratio (HR_adj) 3.99 (95% Confidence Interval (CI) 1.40–11.33), in node-negative patients HR_adj 1.88 (95% CI 1.11–3.17), and in non-AI-treated patients HR_adj 1.81 (95% CI 1.01–3.24), but decreased recurrence-risk in AI-treated patients HR_adj 0.46 (95% CI 0.25–0.84) and in patients with lobular cancer HR_adj 0.15 (95% CI 0.04–0.64). MHT was associated with lower risk of death in node-positive patients HR_adj of 0.48 (95% CI 0.27–0.86) and in AI-treated patients HR_adj of 0.41 (95% CI 0.22–0.77), but not in other patients (both P_interactions≤ 0.027). A history of MHT may have prognostic value for certain subgroups of breast cancer patients such as AI-treated or node-negative patients.

The impact of body size changes on recurrence risk depends on age and estrogen receptor status in primary breast cancer

PURPOSE

To investigate the prognostic impact of body size changes during the first postoperative year in breast cancer.

METHODS

A cohort of 1,317 primary breast cancer patients included in Sweden (2002-2014) underwent body size measurements at the preoperative and 1-year visits (n = 1,178). Landmark survival analyses were used to investigate how postoperative weight gain or loss (> 5%) or change in waist-hip ratio (WHR) categories (≤ 0.85 or > 0.85) impact prognosis.

RESULTS

Median age at inclusion was 61 years and body mass index 25.1 kg/m². After a median follow-up of 5.0 years from inclusion, 165 recurrences and 77 deaths occurred. Weight gain (17.0%) conferred over twofold recurrence risk only in patients < 50 years (P_interaction = 0.033). Weight loss (8.6%) was only associated with a poor prognosis in patients ≥ 70 years, but not after restriction analysis. Weight change did not impact prognosis in patients 50 to < 70 years. Changes between WHR categories were associated with differential recurrence risk depending on estrogen receptor (ER) status (P_interaction = 0.007), with higher recurrence risk in patients with ER+ tumors and lower recurrence risk with ER- tumors.

CONCLUSION

Both changes in terms of weight and WHR category yielded independent prognostic information. Further research is imperative before recommending weight loss for all overweight breast cancer patients.

Interactions Between ABCB1 Genotype and Preoperative Statin Use Impact Clinical Outcomes Among Breast Cancer Patients

Multiple clinical trials investigate statins' effects in breast cancer. The ABCB1 genotype appears to influence statin response and toxicity in the cardiovascular setting. This exploratory study aimed to investigate the interplay between preoperative statin use, ABCB1 genotype, and tumor-specific expression of the statin target 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) in breast cancer. Preoperative statin use, ABCB1 C3435T genotype, and HMGCR expression in relation to outcome were analyzed in 985 primary breast cancer patients from a population-based prospective cohort in Sweden from 2002 to 2012. Preoperative statin use (n = 80) was not associated with ABCB1 C3435T genotype (n = 576), HMGCR expression (n = 848), or clinical outcomes. ABCB1 C3435T TT-carriers had lower risk of breast cancer events than any C-carriers (adjusted hazard ratio (HR_adj) 0.74; 95%CI 0.49, 1.12), but only in non-statin users (P_interaction = 0.042). Statin users with TT genotype had higher risk of distant metastasis (HR_adj 4.37; 95%CI 1.20, 15.91; P_interaction = 0.009) and shorter overall survival than other patients (HR_adj 3.77; 95%CI 1.37, 10.39; P_interaction = 0.019). In conclusion, there were nominally significant interactions between ABCB1 genotype and preoperative statin use on clinical outcomes, while preoperative statin use was not associated with outcomes. Since this is an exploratory study of the impact of the ABCB1 genotype in relation to statin use and clinical outcomes in the breast cancer setting, the results should be interpreted with caution and warrant replication in an independent cohort, preferably in a randomized setting. Since statin use is common in breast cancer patients, it would be of interest to further elucidate the clinical impact of the ABCB1 genotype in breast cancer.

Increasing preoperative body size in breast cancer patients between 2002 and 2016: implications for prognosis

Overweight and obesity are increasing worldwide, but the extent in breast cancer patients is unknown. The two aims were to study secular trends in preoperative body mass index (BMI), waist circumference, and breast volume and their impacts on clinical outcome. BMI, waist circumference, and breast volume were measured preoperatively in 24–99-year-old primary breast cancer patients (n = 640) in Sweden 2002–2016. The measurements were analyzed alone and combined in relation to recurrence and overall survival (OS). BMI, waist circumference, and breast volume increased 2002–2016 (p_trends < 0.0001). Of these, a breast volume ≥ 850 mL was associated with the strongest recurrence-risk (adjusted hazard ratio [_adjHR] 1.67; 95% CI 1.17–2.39), especially combined with waist circumference ≥ 80 cm (_adjHR 2.07; 95% CI 1.25–3.44), while BMI ≥ 25 kg/m² or large waist circumference conferred almost a twofold risk for death (both Log-Rank p ≤ 0.0001). Chemotherapy seemed to counteract the negative impact of a high BMI or large waist circumference on OS. Large breast volume was the strongest predictor for recurrence in all treatment groups. In conclusion, preoperative BMI, waist circumference, and breast volume increased between 2002 and 2016. Larger body size negatively impacted breast cancer-free interval and OS. If confirmed, body measurements may help select patients requiring more individualized treatment.

Combined and individual tumor-specific expression of insulin-like growth factor-I receptor, insulin receptor and phospho-insulin-like growth factor-I receptor/insulin receptor in primary breast cancer: Implications for prognosis in different treatment groups

Clinical trials examining insulin-like growth factor-I receptor (IGF1R)-targeting strategies have emphasized that better predictive biomarkers are required to improve patient selection.

Immunohistochemical tumor-specific protein expression of IGF1R, insulin receptor (InsR), and phosphorylated IGF1R/InsR (pIGF1R/InsR) individually and combined in relation to breast cancer prognosis was evaluated in a population-based cohort of 1,026 primary invasive breast cancer patients without preoperative treatment diagnosed in Sweden. IGF1R (n = 923), InsR (n = 900), and pIGF1R/InsR (n = 904) combined cytoplasmic and membrane staining was dichotomized. IGF1R^strong/InsR^mod/strong/pIGF1R/InsR^pos tumors were borderline associated with 2-fold risk for events, HR_adj (2.00; 95%CI 0.96-4.18). Combined IGF1R and pIGF1R/InsR status only impacted prognosis in patients with InsR^mod/strong expressing tumors (P_interaction = 0.041). IGF1R^strong expression impacted endocrine treatment response differently depending on patients’ age and type of endocrine therapy. Phospho-IGF1R/InsR^pos was associated with lower risk for events among non-endocrine-treated patients irrespective of ER status, HR_adj (0.32; 95%CI 0.16-0.63), but not among endocrine-treated patients (P_interaction = 0.024). In non-endocrine-treated patients, pIGF1R/InsR^pos was associated with lower risk for events after radiotherapy, HR_adj (0.31; 95%CI 0.12-0.80), and chemotherapy, HR_adj (0.29; 95%CI 0.09-0.99). This study highlights the complexity of IGF hetero-and homodimer signaling network and its interplay with endocrine treatment, suggesting that combinations of involved factors may improve patient selection for IGF1R-targeted therapy.

Current smoking is associated with a larger waist circumference and a more androgenic profile in young healthy women from high-risk breast cancer families

The purpose was to elucidate the interplay between current smoking, anthropometric measurements, and endogenous hormone levels in women ≤ 40 years. Questionnaires on lifestyle and reproductive factors were completed by 269 healthy women from high-risk breast cancer families between 1996 and 2006 in Sweden. Blood samples for analyses of plasma testosterone, estradiol, androstenedione, sex hormone-binding globulin, and body measurements were obtained 5–10 days before predicted onset of the next menstrual period. Women without smoking status, who were currently breastfeeding, or using hormonal contraception other than combined oral contraceptives (OCs) were excluded (n = 27). Current smokers (n = 57) had larger waist circumference (_adjp = 0.004) and waist-to-hip ratio (WHR) (_adjp = 0.007) than non-smokers (n = 185). In non-OC users, adjusted mean androstenedione levels were higher in current smokers compared with non-smokers (10.3 vs. 8.6 nmol/L; _adjp = 0.0002). While in current OC users estradiol levels were higher in smokers compared with non-smokers (22.5 vs. 17.4 pg/mL; _adjp = 0.012). In multivariable models, WHR was associated with both current smoking (_adjp ≤ 0.016) and higher levels of androstenedione (_adjp = 0.05) or bioavailable testosterone (_adjp = 0.001). Among non-OC users, a more androgenic profile was observed in current smokers compared with non-smokers, but not in current OC users. Irrespective of OC use, current smoking was associated with increased waist circumference.

Coffee Is Associated With Lower Breast Tumor Insulin-Like Growth Factor Receptor 1 Levels in Normal-Weight Patients and Improved Prognosis Following Tamoxifen or Radiotherapy Treatment

Coffee is associated with decreased breast cancer risk, but the impact of body mass index (BMI) in combination with coffee consumption on prognosis is unclear. The suppressive effect of coffee constituents on the insulin-like growth factor receptor 1 (IGF1R) levels in breast cancer cells may play a role. The aim was to investigate the prognostic impact of coffee consumption and possible associations with tumor-specific IGF1R protein expression and BMI in a population-based cohort in Sweden, comprising 1,014 primary breast cancer patients without pretreatment enrolled 2002-2012 and followed for up to 13 years. Patients with higher coffee consumption had lower tumor IGF1R levels (P = 0.025), but only among the normal-weight patients (P = 0.005). Coffee did not impact the recurrence-risk overall. However, tamoxifen-treated patients with ER⁺ tumors drinking ≥ 2 cups of coffee/day had lower recurrence-risk [adjusted HR (HR_adj) 0.57, 95% CI, 0.34-0.97] compared with patients with lower intake, although only among normal-weight patients (HR_adj 0.37, 95% CI: 0.17-0.78; P_interaction = 0.039). Similarly, coffee consumption ≥ 2 cups/day was associated with significantly lower recurrence-risk among the 640 radiotherapy-treated patients irrespective of BMI (HR_adj 0.59, 95% CI 0.36-0.98) and in the 296 normal-weight patients (HR_adj 0.36, 95% CI 0.17-0.76) but not in the 329 overweight or obese patients (HR_adj 0.88, 95% CI 0.42-1.82) although the interaction was not significant (P_interaction = 0.093). In conclusion, coffee consumption was negatively associated with tumor-specific IGF1R levels only among normal-weight patients. Though, IGF1R did not explain the association between coffee intake and improved prognosis among normal-weight tamoxifen- or radiotherapy-treated patients. Studies of IGF1R-targeting therapies may benefit from taking BMI and coffee consumption into account.

Prediagnostic Smoking Is Associated with Binary and Quantitative Measures of ER Protein and ESR1 mRNA Expression in Breast Tumors

Background: Smoking is a possible risk factor for breast cancer and has been linked to increased risk of estrogen receptor-positive (ER⁺) disease in some epidemiologic studies. It is unknown whether smoking has quantitative effects on ER expression.Methods: We examined relationships between smoking and ER expression from tumors of 1,888 women diagnosed with invasive breast cancer from a population-based study in North Carolina. ER expression was characterized using binary (±) and continuous measures for ER protein, ESR1 mRNA, and a multigene luminal score (LS) that serves as a measure of estrogen signaling in breast tumors. We used logistic and linear regression models to estimate temporal and dose-dependent associations between smoking and ER measures.Results: The odds of ER⁺, ESR1⁺, and LS⁺ tumors among current smokers (at the time of diagnosis), those who smoked 20 or more years, and those who smoked within 5 years of diagnosis were nearly double those of nonsmokers. Quantitative levels of ESR1 were highest among current smokers compared with never smokers overall [mean (log₂) = 9.2 vs. 8.7, P < 0.05] and among ER⁺ cases; however, we did not observe associations between smoking measures and continuous ER protein expression.Conclusions: In relationship to breast cancer diagnosis, recent smoking was associated with higher odds of the ER⁺, ESR1⁺, and LS⁺ subtype. Current smoking was associated with elevated ESR1 mRNA levels and an elevated LS, but not with altered ER protein.Impact: A multigene LS and single-gene ESR1 mRNA may capture tumor changes associated with smoking. Cancer Epidemiol Biomarkers Prev; 27(1); 67-74. ©2017 AACR.

State of the evidence 2017: an update on the connection between breast cancer and the environment

BACKGROUND

In this review, we examine the continually expanding and increasingly compelling data linking radiation and various chemicals in our environment to the current high incidence of breast cancer. Singly and in combination, these toxicants may have contributed significantly to the increasing rates of breast cancer observed over the past several decades. Exposures early in development from gestation through adolescence and early adulthood are particularly of concern as they re-shape the program of genetic, epigenetic and physiological processes in the developing mammary system, leading to an increased risk for developing breast cancer. In the 8 years since we last published a comprehensive review of the relevant literature, hundreds of new papers have appeared supporting this link, and in this update, the evidence on this topic is more extensive and of better quality than that previously available.

CONCLUSION

Increasing evidence from epidemiological studies, as well as a better understanding of mechanisms linking toxicants with development of breast cancer, all reinforce the conclusion that exposures to these substances - many of which are found in common, everyday products and byproducts - may lead to increased risk of developing breast cancer. Moving forward, attention to methodological limitations, especially in relevant epidemiological and animal models, will need to be addressed to allow clearer and more direct connections to be evaluated.

Body Mass Index Influences the Prognostic Impact of Combined Nuclear Insulin Receptor and Estrogen Receptor Expression in Primary Breast Cancer

The prognostic importance of tumor-specific nuclear insulin receptor (InsR) expression in breast cancer is unclear, while membrane and cytoplasmic localization of InsR is better characterized. The insulin signaling network is influenced by obesity and may interact with the estrogen receptor α (ERα) signaling. The purpose was to investigate the interplay between nuclear InsR, ER, body mass index (BMI), and prognosis. Tumor-specific expression of nuclear InsR was evaluated by immunohistochemistry in tissue microarrays from 900 patients with primary invasive breast cancer without preoperative treatment, included in a population-based cohort in Sweden (2002-2012) in relation to prognosis. Patients were followed for up to 11 years during which 107 recurrences were observed. Nuclear InsR⁺ expression was present in 214 patients (23.8%) and increased with longer time between surgery and staining (P < 0.001). There were significant effect modifications by ER status and BMI in relation to clinical outcomes. Nuclear InsR⁺ conferred higher recurrence-risk in patients with ER⁺ tumors, but lower risk in patients with ER^- tumors (P_interaction = 0.003). Normal-weight patients with nuclear InsR⁺ tumors had higher recurrence-risk, while overweight or obese patients had half the recurrence-risk compared to patients with nuclear InsR^- tumors (P_interaction = 0.007). Normal-weight patients with a nuclear InsR^-/ER⁺ tumor had the lowest risk for recurrence compared to all other nuclear InsR/ER combinations [HR_adj 0.50, 95% confidence interval (CI): 0.25-0.97], while overweight or obese patients with nuclear InsR^-/ER^- tumors had the worst prognosis (HR_adj 7.75, 95% CI: 2.04-29.48). Nuclear InsR was more prognostic than ER among chemotherapy-treated patients. In summary, nuclear InsR may have prognostic impact among normal-weight patients with ER⁺ tumors and in overweight or obese patients with ER^- tumors. Normal-weight patients with nuclear InsR^-/ER⁺ tumors may benefit from less treatment than normal-weight patients with other nuclear InsR/ER combinations. Overweight or obese patients with nuclear InsR^-/ER^- tumors may benefit from more tailored treatment or weight management.

High Estrogen Receptor β Expression Is Prognostic among Adjuvant Chemotherapy-Treated Patients-Results from a Population-Based Breast Cancer Cohort

PURPOSE

Isoform-specific tumor estrogen receptor β (ERβ) expression may hold prognostic information in breast cancer, especially among endocrine-treated breast cancer patients. The study's purpose was to evaluate ERβ isoform 1 (ERβ1) expression in relation to tumor characteristics, ESR2 genotypes, and prognosis in different treatment groups.

EXPERIMENTAL DESIGN

A population-based prospective cohort of 1,026 patients diagnosed with primary invasive breast cancer in Lund, Sweden, between October 2002 and June 2012 was followed until June 2014 (median 5 years). Associations between immunohistochemical ERβ1 expression, patient and tumor characteristics, as well as outcome within treatment groups were analyzed.

RESULTS

Tumor ERβ1 expression was available for 911 patients (89%) and was not associated with ESR2 genotypes. ERβ1 positivity, defined as >75% (ERβ1₇₅⁺, 72.7%), was positively associated with established favorable tumor characteristics. Overall, ERβ1₇₅⁺ was associated with lower risk of breast cancer events [HR_adj = 0.60; 95% confidence interval (CI), 0.41-0.89]. The magnitude of the association was larger in patients with ERα^- tumors (HR_adj = 0.30; 95% CI, 0.12-0.76), compared with ERα⁺ tumors (HR_adj = 0.66; 95% CI, 0.42-1.03). Among the 232 chemotherapy-treated patients, ERβ1₇₅⁺ tumors were associated with lower risk of breast cancer events compared with ERβ1₇₅^- tumors (HR_adj = 0.31; 95% CI, 0.15-0.64). Among the 671 chemonaïve patients, ERβ1₇₅ status was not associated with the outcome.

CONCLUSIONS

High ERβ1 expression was a favorable prognostic marker in this breast cancer cohort, especially in chemotherapy-treated patients, but not in endocrine therapy-treated patients. These results warrant confirmation, preferably via a biomarker study in a previously conducted randomized trial. Clin Cancer Res; 23(3); 766-77. ©2016 AACR.

Breast Cancer Metastasis Associations with Clinicopathological Characteristics in Mexican Women Younger than 40 Years of Age

Background:

In Mexico, breast cancer (BCa) is in first place regarding cancer mortality and has been established as a priority health issue. The incidence of metastasis from BCa is very high and presents as the principal mortality factor among women younger than 40 years of age. OBJECTIVE. To determine any associations between clinicopathological characteristics and metastasis in Mexican women under 40 years of age.

Methods:

During the 2010–2015 period, a total of 180 female BCa cases seen at the Navy General High Specialty Hospital, SEMAR, in Mexico City; we collected information on 20 patients with BCa younger than 40 years of age. Statistical analyses were conducted using the Kolmogorov–Smirnov, Students t, Fisher, Chi square, and Mantel–Haenszel tests.

Results:

The prevalence of women with BCa younger than the age of 40 years during the 2010–2015 period was 13.3%. We found a high frequency of obesity in of these cases (>75%); 100% of obese patients with a history of smoking presented with metastasis (p <0.05). In addition, the hormone phenotype was important; HER2-positive cases were 12 times more likely tto exhibit metastasis (p <0.05), while expression of estrogen and progesterone receptors appeared to be protective. Diabetes mellitus in combination with smoking was also a risk factor for development of metastasis (p <0.05).

Conclusion:

In this study, we obtained essential data regarding risk of metastasis in young breast cancer cases which could be useful for predicting disease evolution and treatment response.