Improvements in breast cancer survival between 1995 and 2012 in Denmark: The importance of earlier diagnosis and adjuvant treatment

Understanding quality of life in Danish women with metastatic breast cancer undergoing multiple treatments

BACKGROUND

Women with metastatic breast cancer (mBC) may experience several symptoms exacerbated by successive treatments. There is however, a lack of knowledge of the most important symptoms and how these may affect daily life function. This study aims to elucidate the quality of life (QoL), including both symptoms and daily life functions, among mBC women undergoing varied treatments.

METHODOLOGY

We conducted a cross-sectional electronic questionnaire study enrolling mBC women (≥ stage III) receiving medical cancer treatment through September-December 2023. QoL, symptoms, and daily life function were measured using the European Organization for Research and Treatment of Cancer (EORTC) core questionnaire (QLQ-C30) and the breast cancer module (BR45). Health-related quality of life (HRQoL), defined by the EORTC, covers the subjective perceptions of the positive and negative aspects of cancer patients' symptoms, including physical, emotional, social, and cognitive functions. We examined associations between QoL, treatment line and therapy types, and estimated odds ratios (ORs) and confidence intervals (CIs).

RESULTS

Of 359 eligible participants, 111 responded (30.9%). At study commencement, 90.9% of the participants received at least one type of systemic treatment, with 16.2% undergoing chemotherapy, 61.3% anti-hormonal treatment, and 66.6% targeted cancer treatment. QLQ-C30 sum scores were highest in women receiving anti-hormonal treatment (80.7, interquartile range [IQR]: 17.6), followed by targeted cancer treatment (78.8, IQR: 18.4), and lowest with chemotherapy (77.1, IQR: 24.8). Quality of life decreased with subsequent treatment lines (first line: 80.3, IQR: 20.7, fourth line: 67.4, IQR: 11.3). No significant differences were found in the functions or in the individual symptoms according to monotherapy type.

INTERPRETATION

Women with mBC experience a substantial symptom burden and reduced functioning, and their QoL differs with successive lines of treatment. This underlines that women living with mBC need support and effective symptom management to maintain QoL.

High comorbidity and tumor proliferation predict survival of localized breast cancer patients after curative surgery: A retrospective analysis of real-world data in Finland

BACKGROUND

The aim of this study was to analyze the characteristics of breast cancer patients and their impact on real-world treatment and survival outcomes.

PATIENTS AND METHODS

We conducted a retrospective study including all patients newly diagnosed with breast cancer during 2019 in the Southwest Finland. We identified 458 patients diagnosed with either localized (n = 435, 95 %) or metastatic (n = 23, 5 %) breast cancer.

RESULTS

In localized breast cancer, the five-year overall survival (OS) was 90.9 %, while the five-year disease-free survival (DFS) was 93.5 %. In metastatic breast cancer, the five-year progression-free survival (PFS) was 13.0 % and five-year OS 34.2 %. The median PFS was 10.9 months (95 % CI 2.5-19.4 months) and median OS was 30.6 months (lower 95 % CI 6.9 months - not reached). In the univariate analyses, the most important tumor-specific parameters predicting decreased DFS were tumor proliferation index >20 %, low estrogen receptor expression status and tumor size >2 cm. Univariate predictors for decreased OS included Eastern Cooperative Oncology Group (ECOG) performance status ≥2 and Charlson Comorbidity Index (CCI) score ≥3. In the multivariable analyses, CCI score ≥3 and high proliferation index (21-100 % vs. 0-20 %) predicted poorer DFS, while CCI score ≥3 and increased stage (stage 2 vs. 1) predicted poorer OS. The administration of post-operative radiotherapy was significant in the multivariable analyses of both DFS (HR 4.23, 95 % CI 1.85-9.67, p = 0.0006) and OS (HR 6.84, 95 % CI 3.33-14.02, p < 0.0001).

CONCLUSION

Our results demonstrate that careful clinical evaluation of ECOG and comorbidities, alongside well-established tumor characteristics predict patient survival in a population where overall five-year survival in breast cancer is over 90 %.

Capecitabine monotherapy as first-line treatment in advanced HER2-normal breast cancer - a nationwide, retrospective study

Background and purpose: Capecitabine can be used as first-line treatment for advanced breast cancer. However, real-world data on efficacy of capecitabine in this setting is sparse. The purpose of the study is to evaluate outcomes of patients with Human Epidermal Growth Factor Receptor (HER2)-normal advanced breast cancer treated with capecitabine monotherapy as first-line treatment.

MATERIAL AND METHODS

The study utilized the Danish Breast Cancer Group (DBCG) database and was conducted retrospectively across all Danish oncology departments. Inclusion criteria were female patients, with HER2-normal advanced breast cancer treated with capecitabine monotherapy as the first-line treatment from 2010 to 2020. The primary endpoints were overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 494 patients were included. Median OS was 16.4 months (95% confidence interval [CI]: 14.5-18.0), and median PFS was 6.0 months (95% CI: 5.3-6.7). Patients with estrogen receptor (ER)-positive disease had significantly longer OS (median: 22.8 vs. 10.5 months, p < 0.001) and PFS (median: 7.4 vs. 4.9 months, p = 0.003), when compared to ER-negative patients. Stratifying by age, patients under 45 years displayed a median PFS of 4.1 months, while those aged 45-70 years and over 70 years had median PFS of 5.7 and 7.2 months, respectively (p = 0.01).

INTERPRETATION

 In this nationwide study, the efficacy of capecitabine as a first-line treatment for HER2-normal advanced breast cancer is consistent with other, mainly retrospective, studies. However, when assessed against contemporary and newer treatments, its effectiveness appears inferior to alternative chemotherapies or targeted therapies.

Impact of type 2 diabetes on complications after primary breast cancer surgery: Danish population-based cohort study

BACKGROUND

Knowledge is sparse on the impact of type 2 diabetes (T2D) on surgical outcomes after breast cancer surgery. This study investigated the association between T2D and risk of complications after primary breast cancer surgery, and evaluated the biological interaction between T2D and co-morbidities.

METHODS

Using the Danish Breast Cancer Group clinical database, a cohort of all Danish women diagnosed with early-stage breast cancer during 1996-2022 was created. All patients underwent mastectomy or breast-conserving surgery. Information on prevalent T2D was collected from Danish medical and prescription registries. Surgical complications were defined as hospital diagnoses for medical or surgical complications developing within 30 days after primary breast cancer surgery. The 30-day cumulative incidence proportion of complications was calculated, and Cox regression was used to estimate HRs. Interaction contrasts were computed to determine the additive interaction between T2D and co-morbidities on the incidence rate of complications.

RESULTS

Among 98 589 women with breast cancer, 6332 (6.4%) had T2D at breast cancer surgery. Overall, 1038 (16.4%) and 9861 (10.7%) women with and without T2D developed surgical complications, yielding cumulative incidence proportions of 16 (95% c.i. 15 to 17) and 11 (10 to 11)% respectively, and a HR of 1.43 (95% c.i. 1.34 to 1.53). The incidence rate of surgical complications explained by the interaction of T2D with moderate and severe co-morbidity was 21 and 42%, respectively.

CONCLUSION

Women with breast cancer and T2D had a higher risk of complications after primary breast cancer surgery than those without T2D. A synergistic effect of T2D and co-morbidity on surgical complications can explain this association.

Left atrial strain is reduced following trastuzumab in breast cancer patients

BACKGROUND

The effect of trastuzumab therapy on left atrial (LA) function remains largely unknown. Our aim was to assess the changes in LA strain parameters longitudinally in patients treated with trastuzumab.

METHODS

We retrospectively studied 170 patients with stage I-IV HER2+ breast cancer. All patients had baseline echocardiograms and repeat echocardiograms at 3 months and after 1 year. We measured LA strain at all three time points. Changes in LA strain and strain rate (sr) parameters were evaluated using repeated-measures mixed-effects models. The cohort was stratified according to development of cancer therapeutics-related cardiac dysfunction (CTRCD) during follow-up.

RESULTS

The mean age was 52.7 ± 13.8 years, 25.3% had hypertension and 16.0% had metastatic disease. Multiple LA strain parameters (predicted delta value, [95%CI]) showed statistically significant declines in patients who developed CTRCD from baseline to the 3-month follow-up after multivariable adjustment; LA reservoir strain (LAεres ): -4.7%; [-8.1% to -1.3%], p = .007; LA conduit strain (LAεcon ): -2.8%; [-5.3% to -.4%], p = .021); and LAεres sr: -.2/s; [-.3/s to -.09/s], p < .001). In patients who did not develop CTRCD, LA strain parameters declined significantly but to a smaller degree than in the CTRCD group (LAεres : -1.7%; [-3.1% to -.3%], p = .020, LAεcon : -2.2%; [-3.3% to -1.1%], p < .001, and LA booster pump strain : -2.4%; [-3.5% to -1.4%], p < .001). LA strain rates did not decline significantly in the non-CTRCD group.

CONCLUSION

Trastuzumab treatment was associated with declines in LA strain parameters in patients with breast cancer. The largest declines were observed in patients who developed CTRCD during treatment.

Long-term quality of life among breast cancer survivors eligible for screening at diagnosis: a systematic review and meta-analysis

OBJECTIVES

This study aimed to explore the long-term quality of life (QoL) among breast cancer survivors eligible for mammographic screening at diagnosis and compare that to QoL among women with no history of breast cancer.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic review of randomised controlled trials and observational studies published between January 2000 and July 2019 was performed. Eight studies were included in the review. Six studies with QoL measurement scales (0-100) were included in the meta-analysis. We used fixed and random effects models to obtain Cohen's d with 95% confidence interval (CI). Heterogeneity among studies was evaluated by the I² statistics.

RESULTS

Information about 6145 breast cancer survivors diagnosed between 1995 and 2012 and followed for >1-10 years was analysed. Four studies used SF-36/RAND-36, three studies used EORTC QLQ-C30, one study used FACT-G and one study used FACT-B. The mean score of QoL for breast cancer survivors varied from 63.0 (RAND SF-36, 0-100) to 110.5 (FACT-B, 0-123). Two studies showed better, three studies showed similar and two studies showed poorer mean scores for breast cancer survivors compared with women with no history of breast cancer. The meta-analysis showed no significant differences in QoL for breast cancer survivors compared with women with no history of breast cancer (Cohen's d = -0.07, 95% confidence interval [CI] -0.14 to 0.00 and I² = 83.7% for the fixed effect model; Cohen's d = -0.00, 95% CI -0.18 to 0.17 and I² = 82.4% for the random effects model).

CONCLUSION

QoL did not differ between breast cancer survivors eligible for mammographic screening at diagnosis and followed for >1-10 years and women with no history of breast cancer.

Survival of breast cancer patients in German-Danish border regions - A registry-based cohort study

BACKGROUND AND AIM

Denmark reports slightly lower breast cancer survival before 2010 than its neighbouring country Germany. Previous research is limited by lacking stage and treatment information. This study aims to investigate differences in breast cancer survival between the bordering regions Schleswig-Holstein (Germany), Southern Denmark and Zealand (Denmark) using registry data including stage and treatment information.

METHOD

Invasive female breast cancer cases diagnosed during 2004-2013 with follow up through 31st December 2014 were extracted from cancer registries. Cases notified by death certificates only and those aged 90+ years were excluded. Kaplan-Meier curves and log-rank tests were computed. Cox regression analysis was conducted with adjustment for year of diagnosis, age, stage, and treatment.

RESULTS

The analytical sample included 42,966 cases. Kaplan-Meier curves and log-rank tests show significant survival differences between the regions. The Cox regression model adjusted for year of diagnosis and age shows significantly worse overall survival of breast cancer patients in both Danish regions compared to Schleswig-Holstein with hazard ratios (HR) of 1.09 (95 % CI: 1.04; 1.15) for patients from Southern Denmark (SD) and 1.25 (95 % CI: 1.18; 1.32) for residents of Zealand (ZL). This effect diminished after adjustment for stage and treatment (HR: 1.05 (SD), 1.09 (ZL) 95 % CI: 0.99; 1.10 (SD), 1.03; 1.15 (ZL)).

CONCLUSION

Survival differences can be explained by differing stage distribution and treatment administration, which formerly were more favourable in Schleswig-Holstein. The survival gap will probably close due to Denmark's national screening program and increased use of adjuvant cancer therapy.

An Artificial Intelligence-Enabled Pipeline for Medical Domain: Malaysian Breast Cancer Survivorship Cohort as a Case Study

Automated artificial intelligence (AI) systems enable the integration of different types of data from various sources for clinical decision-making. The aim of this study is to propose a pipeline to develop a fully automated clinician-friendly AI-enabled database platform for breast cancer survival prediction. A case study of breast cancer survival cohort from the University Malaya Medical Centre was used to develop and evaluate the pipeline. A relational database and a fully automated system were developed by integrating the database with analytical modules (machine learning, automated scoring for quality of life, and interactive visualization). The developed pipeline, iSurvive has helped in enhancing data management as well as to visualize important prognostic variables and survival rates. The embedded automated scoring module demonstrated quality of life of patients whereas the interactive visualizations could be used by clinicians to facilitate communication with patients. The pipeline proposed in this study is a one-stop center to manage data, to automate analytics using machine learning, to automate scoring and to produce explainable interactive visuals to enhance clinician-patient communication along the survivorship period to modify behaviours that relate to prognosis. The pipeline proposed can be modelled on any disease not limited to breast cancer.

Loco-regional recurrence trend and prognosis in young women with breast cancer according to molecular subtypes: analysis of 1099 cases

BACKGROUND

The number of young patients diagnosed with breast cancer is on the rise. We studied the rate trend of local recurrence (LR) and regional recurrence (RR) in young breast cancer (YBC) patients and outcomes among these patients based on molecular subtypes.

METHODS

A retrospective cohort study was conducted based on data from Tianjin Medical University Cancer Institute and Hospital for patients ≤ 35 years of age with pathologically confirmed primary invasive breast cancer surgically treated between 2006 and 2014. Patients were categorized according to molecular subtypes on the basis of hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status. The 5-year rates for LR, RR, and distant metastases (DM) were estimated by Kaplan-Meir statistics. Nelson-Aalen cumulative-hazard plots were used to describe local recurrence- and distant metastasis-free intervals.

RESULTS

We identified 25,284 patients with a median follow-up of 82 months, of whom 1099 (4.3%) were YBC patients ≤ 35 years of age. The overall 5-year LR, RR, and DM rates in YBC patients were 6.7%, 5.1%, and 16.6%, respectively. The LR and RR rates demonstrated a decreasing trend over time (P = 0.028 and P = 0.015, respectively). We found that early-stage breast cancer and less lymph node metastases increased over time (P = 0.004 and P = 0.007, respectively). Patients with HR-/HER2+ status had a significantly higher LR (HR 20.4; 95% CI, 11.8-35.4) and DM (HR 37.2; 95% CI, 24.6-56.3) at 10 years. Breast-conserving surgery (BCS) or mastectomy did not influence rates of LR and RR. In the overall population, the 5-year survival of YBC patients exceeded 90%.

CONCLUSIONS

The rates of LR and RR with YBC patients demonstrated a downward trend and the proportion of early-stage breast cancer increased between 2006 and 2014. We report the highest LR rates in this young population were associated with HR-/HER2+ tumors.

Risk of coronary artery disease after adjuvant radiotherapy in 29,662 early breast cancer patients: A population-based Danish Breast Cancer Group study

PURPOSE

Radiotherapy (RT) for early breast cancer (BC) reduces the risk of recurrence and improves overall survival. However, thoracic RT may cause some incidental RT dose to the heart with subsequent risk of heart disease. During 2000-2010, CT-based RT planning was gradually introduced. The aim of this study was to investigate the risk of cardiac events in left-sided compared with right-sided BC patients treated during a non-CT-based (1999-2007) vs a CT-based period (2008-2016).

MATERIAL AND METHODS

Information on BC and cardiac events among Danish women was obtained from population-based medical registers. Patients diagnosed with BC during 1999-2016, were included. A cardiac event was defined as coronary artery disease or severe valvular heart disease.

RESULTS

Among 29,662 patients, 22,056 received RT. For those irradiated during the non-CT-based period, the 10-year cumulative risk of cardiac event was 1.7% (95% CI 1.4-2.0) at median follow-up of 11.1 years. The incidence rate ratio (IRR) for cardiac event in left-sided vs right-sided patients was 1.44 (1.07-1.94) and a trend towards worse outcome was seen within the first 10 years after RT and approached statistical significance with longer follow-up. Among patients irradiated during the CT-based period, the 10-year cumulative risk of cardiac event was 2.1% (1.8-2.4) at median 6.8 years follow-up. The IRR for cardiac event in left-sided vs right-sided patients was 0.90 (0.69-1.16) and no trend towards worse outcome within the first 10 years was observed.

CONCLUSION

This study confirmed a higher risk of cardiac events in left-sided vs right-sided BC patients irradiated during a non-CT-based period. For patients irradiated during a CT-based period, no increased risk of cardiac events in left-sided vs right-sided patients was observed within the first 10 years after RT, whilst information on cardiac events beyond 10 years after RT was limited.

Neoadjuvant chemotherapy and HER2 dual blockade including biosimilar trastuzumab (SB3) for HER2-positive early breast cancer: Population based real world data from the Danish Breast Cancer Group (DBCG)

BACKGROUND

Dual blockade with trastuzumab and pertuzumab combined with neoadjuvant chemotherapy (NACT) has been increasingly used for HER2-positive tumours >2 cm and/or with positive axillary lymph nodes in order to evaluate pathologic response and obtain better surgical management. SB3 is a registered biosimilar trastuzumab approved following a phase III trial demonstrating similar efficacy in the neoadjuvant setting as trastuzumab. However, the study was done without pertuzumab.

METHOD

The database of the Danish Breast Cancer Group was used to extract data on all patients who started NACT with SB3 and pertuzumab between September 1, 2018 and August 31, 2019. The primary endpoint was pathological complete response (pCR) rate.

RESULTS

In total 215 patients received NACT and dual blockade. The median age was 55 (24-81). NACT used was cyclophosphamide and epirubicin followed by weekly paclitaxel (62% on six cycles, 35% on eight cycles) or other chemotherapy followed by weekly paclitaxel (3%). Overall, 56% of patients achieved pCR. 60 of 88 node-positive patients pre-NACT achieved ypN0(i-) after neoadjuvant treatment. pCR rate was significantly associated with estrogen receptor status and malignancy grade. An association with CEP17/HER2-ratio was assessed.

CONCLUSION

Real world data on dual blockade with SB3 and pertuzumab in combination with NACT in a nationwide population-based study show a pCR rate comparable to that seen in previous clinical studies.

Prognostic impact of serum levels of EGFR and EGFR ligands in early-stage breast cancer

Epidermal growth factor receptor (EGFR) and its ligands are involved in cancer pathogenesis. The emerging role of treatments co-targeting the EGFR system in breast cancer has increased the need to identify companion biomarkers. The aim of this study is to investigate whether pretreatment serum levels of EGFR and EGFR ligands in early-stage breast cancer patients might provide prognostic information as a stepping stone for further investigation. The study, which included 311 early-stage breast cancer patients, investigated associations between preoperative serum levels of EGFR and EGFR ligands (epidermal growth factor, heparin-binding epidermal growth factor (HBEGF), amphiregulin, transforming growth factor-α and betacellulin) and survival. Cutoffs were determined using Youden’s method, and overall survival (OS) and invasive disease-free survival (IDFS) were evaluated using Cox regression. Preoperative S-EGFR < 60.3 ng/mL was associated with shorter OS and IDFS in both univariate analyses and when adjusting for standard prognostic factors (p < 0.05). Preoperative S-HBEGF < 21.4 pg/mL was associated with shorter OS in both univariate and multivariate analyses, whereas association with shorter IDFS could only be demonstrated in the univariate analysis. In conclusion, our study demonstrated shorter survival in early-stage breast cancer patients who had low pretreatment levels of either S-EGFR or S-HBEGF.

Rates of re-excision and conversion to mastectomy after breast-conserving surgery with or without oncoplastic surgery: a nationwide population-based study

Background

There is no consensus regarding the impact of oncoplastic surgery (OPS) on rates of re‐excision and conversion to mastectomy following breast‐conserving surgery (BCS). Here these two outcomes after BCS and OPS were compared in a nationwide population‐based setting.

Methods

In Denmark, all OPS is registered and categorized into volume displacement, volume reduction or volume replacement. Patients who underwent BCS or OPS between 2012 and 2018 were selected from the Danish Breast Cancer Group database. Multivariable analyses were performed to adjust for confounders, and propensity score matching to limit potential confounding by indication bias.

Results

A total of 13 185 patients (72·5 per cent) underwent BCS and 5003 (27·5 per cent) OPS. Volume displacement was used in 4171 patients (83·4 per cent), volume reduction in 679 (13·6 per cent) and volume replacement in 153 (3·1 per cent). Re‐excision rates were 15·6 and 14·1 per cent after BCS and OPS respectively. After adjusting for confounders, patients were less likely to have a re‐excision following OPS than BCS (odds ratio (OR) 0·80, 95 per cent c.i. 0·72 to 0·88), specifically after volume displacement and reduction. The rate of conversion to mastectomy was similar after OPS and BCS (3·2 versus 3·7 per cent; P = 0·105), but with a lower risk in adjusted analysis (OR 0·69, 0·58 to 0·84), specifically after volume displacement and reduction procedures. Findings were similar after propensity score matching.

Conclusion

A modest decrease in re‐excision rate and less frequent conversion to mastectomy were observed after OPS compared with BCS.

Effects of a WhatsApp-Delivered Education Intervention to Enhance Breast Cancer Knowledge in Women: Mixed-Methods Study

Background

Breast cancer is the leading cause of cancer-related death in the female population. Health education interventions based on the use of mobile technologies enable the development of health self-care skills and have emerged as alternative strategies for the control of breast cancer. In previous studies, WhatsApp has stood out as a useful tool in health education strategies; however, it has not yet been applied for breast cancer education.

Objective

This study aimed to analyze the potential of WhatsApp as a health education tool used to improve women's knowledge on the risk reduction of breast cancer. It also aimed to understand how women feel sensitized within the WhatsApp group throughout the intervention and how they incorporate information posted to improve knowledge about early detection and risk reduction methods.

Methods

The study involved a pre-post health educational intervention with 35 women (aged 45-69 years) included in a WhatsApp group to share information (audio, video, text, and images) over 3 weeks on the early detection and risk reduction of breast cancer. Data were collected through questionnaires on topics related to risk reduction, as well as qualitative content analysis of group interactions. Effectiveness and feasibility were analyzed through conversations and the comparison of the scores obtained in the questionnaires before and after the intervention.

Results

A total of 293 messages were exchanged (moderator 120 and users 173). The average scores of the participants were 11.21 and 13.68 points before and after the educational intervention, respectively, with sufficient sample evidence that the difference was significant (P<.001). The intervention enabled women to improve their knowledge on all topics addressed, especially “myths and truths,” “incidence,” “clinical manifestations,” and “protective factors.” Some themes emerged from the interactions in the group, including group dynamics, general doubts, personal narratives, religious messages, daily news, and events.

Conclusions

The use of groups for women in WhatsApp for health education purposes seems to be a viable alternative in strategies on breast cancer control, especially as it provides a space for the exchange of experiences and disinhibition. However, the need for a moderator to answer the questions and the constant distractions by members of the group represent important limitations that should be considered when improving this strategy.

Dysregulated EGFR pathway in serum in early-stage breast cancer patients: A case control study

The epidermal growth factor receptor (EGFR) and its ligands are involved in cancer pathogenesis and they might serve as circulating biomarkers. The current study aims to investigate if abnormal pre-treatment serum levels of EGFR and EGFR ligands are present in women with early-stage breast cancer and if up- or downregulation of EGFR and EGFR ligands occur in defined patient subgroups. Pre-treatment serum samples were obtained from 311 women with newly diagnosed early-stage breast cancer and from 419 healthy women and analysed for EGFR and the ligands: Epidermal growth factor (EGF), heparin-binding epidermal growth factor (HBEGF), betacellulin (BTC), amphiregulin (AREG), and transforming growth factor α (TGF-α). Previously, age-dependent 95% reference intervals for EGFR and the EGFR ligands have been established based on the healthy women population. S-EGFR, S-EGF, S-HBEGF, S-AREG, and S-TGFα were all significantly different in women with breast cancer compared to healthy women (p < 0.05). Elevated S-EGFR, according to the reference intervals, was present in 11.3% of breast cancer patients, whereas decreased S-EGF was found in 11.6%. Elevated S-EGFR was associated with estrogen receptor positivity of tumor (ER+) and a subgroup of ER + breast cancer patients showed markedly elevated S-EGFR (>120 ng/mL).

Impact of deviation from guideline recommended treatment on breast cancer survival in Asia

Breast cancer survival has improved with significant progress in treatment and disease management. However, compliance with treatment varies. Treatment guidelines for older patients are unclear. We aim to identify predictors of noncompliance with recommended therapy in a large breast cancer population and assess the impact of noncompliance on survival. Our study included 19,241 non-metastatic female breast cancer patients, of whom 3,158 (16%) died within 10 years post-diagnosis (median survival = 5.8 years). We studied the association between treatment noncompliance and factors with logistic regression, and the impact of treatment noncompliance on survival with a flexible parametric survival model framework. The highest proportion of noncompliance was observed for chemotherapy (18%). Predictors of noncompliance with chemotherapy, radiotherapy and endocrine therapy included age, tumor size, nodal involvement and subtype (except radiotherapy). Factors associated with not receiving surgery included age and subtype. Treatment noncompliance was associated with worse overall survival for surgery (HR: 2.26 [1.80-2.83]), chemotherapy (1.25 [1.11-1.41]), radiotherapy (2.28 [1.94-2.69]) and endocrine therapy (1.70 [1.41-2.04]). Worse survival was similarly observed in older patients for whom guidelines generally do not apply. Our results highlight the importance of following appropriate treatment as recommended by current guidelines. Older patients may benefit from similar recommendations.

Effect of cryotherapy on dose of adjuvant paclitaxel in early-stage breast cancer

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a dose-limiting toxicity of paclitaxel. Though no pharmacological agents have been identified to prevent CIPN, cryotherapy with frozen gloves and socks may reduce the risk of developing CIPN and thereby increase the likelihood of patients completing the planned dose of paclitaxel.

PATIENTS AND METHODS

Among women with early-stage breast cancer who received at least one cycle of paclitaxel, 119 were included in the 2016 cohort who received cryotherapy when they developed symptoms of CIPN, and 96 patients in the 2017 cohort who received prophylactic cryotherapy. From electronic patient records, data were abstracted on dates and doses of adjuvant paclitaxel, dose reductions, cycle delays, symptoms of CIPN, and whether and when frozen gloves and socks were used. The outcome was the proportion of patients completing the planned 720 mg/m² of paclitaxel cumulated over nine cycles. The hazard ratio (HR) of a dose-limiting event due to CIPN was estimated in a Cox proportional hazards model.

RESULTS

In the 2016 cohort, cryotherapy was needed due to symptoms of CIPN in 54 (45%) patients. Significantly, more patients, 77% in the 2017 cohort, completed the planned dose of 720 mg/m² compared with 64% in the 2016 cohort, p = 0.017. The HR of a dose reduction or cessation due to CIPN, adjusted for age and HER-2 status, was 0.50 (95% confidence interval 0.30-0.84), p = 0.009, for the 2017 cohort compared with the 2016 cohort.

CONCLUSIONS

The results of this study suggest that prophylactic cryotherapy may reduce the risk of a dose-limiting event due to CIPN and increase the proportion of patients completing the planned dose of paclitaxel in adjuvant treatment of early-stage breast cancer. Despite this, CIPN remains to be an important dose-limiting toxicity of paclitaxel.

Inflammatory breast cancer: A review from our experience

INTRODUCTION

Inflammatory Breast Cancer (IBC) is a distinct and rare type of breast cancer accounting for up to 6% of all breast cancer cases in Europe. The aim of this study was to investigate diagnostic methods, treatments, and outcome after IBC in patients treated at a single institution in Denmark.

METHOD

All patients treated for IBC at Aarhus University Hospital between 2000 and 2014 were identified and included in the cohort. Survival was assessed using Kaplan-Meier curves and log-rank statistics.

RESULTS

A total of 89 patients were identified with a median follow up of 3.6 years. The overall survival at 5 and 10 years were 41% and 18%, respectively. The disease free survival at 5 and 10 years were 47% and 27%, respectively. Thirty-four percent had distant metastasis at time of diagnosis. Patients with ER positive tumors had a significantly better overall survival than patients with ER negative tumors (p = 0.01).

CONCLUSION

Despite a more aggressive systemic and loco-regional treatment today, IBC is still a very serious disease with a high mortality.

The insulin-like growth factor family and breast cancer prognosis: A prospective cohort study among postmenopausal women in Denmark

OBJECTIVE

Circulating levels of insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) have been associated with breast cancer (BC) risk. The evidence in relation to BC prognosis is limited. We aimed to evaluate the association between pre-diagnostic serum levels of IGF-I, IGF-II, IGFBP-2, IGFBP-3 and BC prognosis (i.e. recurrence, BC specific mortality and all-cause mortality) among women diagnosed with BC. We hypothesized that higher serum levels of IGFs and IGFBPs were associated with poor BC prognosis and that the associations were modified by estrogen receptor (ER) status.

DESIGN

From the Danish Diet, Cancer and Health cohort, 412 postmenopausal women diagnosed with incident BC within 5 years of cohort baseline (1993-1997) were identified. Baseline serum samples were analyzed for IGF-I, IGF-II, IGFBP-2 and IGFBP-3. Follow-up was carried out through 2014 by linkage to national Danish registries. Exposures were related to BC prognosis by Cox Proportional Hazard models; effect modification by ER status was investigated and sensitivity analyses by follow-up time were made.

RESULTS

During a median of 15 years, 106 women experienced recurrence and 172 died (118 due to BC). Overall, no associations were observed between IGF-I, IGF-II, IGFBP-2, IGFBP-3 and BC prognosis and no effect modification by ER status was observed. However, higher levels of IGF-II were associated with higher BC specific mortality [Hazard Ratio (HR) (95% Confidence Intervals (CI)): 1.43 (1.01-2.04)] within 10 years of follow-up. Likewise, higher levels of IGFBP-2 were associated with higher BC specific mortality [HR (95% CI): 1.87 (1.19-2.94)] within 5 years of follow-up. In contrast, higher levels of IGFBP-3 were associated with lower risk of recurrence [HR (95% CI): 0.76 (0.60-0.97)] at 5 years of follow-up and BC specific mortality [HR (95% CI): 0.80 (0.65-0.98)] within 10 years of follow-up.

CONCLUSIONS

The present study did not support an association between higher serum levels of IGFs, IGFBPs and adverse BC prognosis. However, it is possible that the role of the IGF family in the etiology of the 5-10 year BC prognosis is different from that of longer-term BC prognosis.

Surgical breast cancer patient pathway: Experiences of patients and relatives and their unmet needs

BACKGROUND AND AIM

Breast cancer is the most common cancer disease in women worldwide. In Denmark, the law prescribes cancer patient pathways (CPPs) in general and thus also for breast cancer. Although results from patient satisfaction surveys show overall satisfaction with the pathway, a call for improvement has been voiced for some areas. The aim of this study was to explore patients' and relatives' experiences with the surgical breast CPP and to identify any unmet needs.

METHOD

This study was based on focus groups with patients who had surgery for breast cancer, and their relatives. The settings were two Danish surgical breast cancer clinics.

FINDINGS

Overall, patients and relatives found the structure of the surgical breast CPP satisfactory. The time in the surgical department was short, and most patients found it difficult to cope with the situation. Empathy and a supportive relationship between patients, relatives and health-care professionals were of great importance. Five key points were identified in which some of the participants had unmet needs. Suggestions for change were related to information, communication, choice of treatment, flexibility in the pathway and easy access to the clinic after surgery.

CONCLUSION

Although patients and relatives found the CPP for breast cancer satisfactory and well planned, suggestions for change were made relating to unmet needs with respect to five key points in the pathway. Implementing findings from this study in clinical practice requires co-operation between health-care professionals and support from the leaders of the organization.

Knockdown of DNA/RNA-binding protein KIN17 promotes apoptosis of triple-negative breast cancer cells

Effective therapy for breast cancer has been extensively studied worldwide, particularly for triple-negative breast cancer and drug-resistant subtypes. DNA/RNA-binding protein KIN17 (kin17) has been reported to be significantly upregulated in breast cancer cells, and is proposed to serve a role in the regulation of cell proliferation. The present study further investigated the association of kin17-knockdown with breast cancer cell apoptosis. Cell Counting kit-8, flow cytometry, TUNEL assay and caspase 3/7 analysis were performed on MDA-MB-231 cells to determine the association between kin17 and breast cancer cell apoptosis. In addition, western blot analysis was performed to investigate the mechanism of kin17 in the apoptosis of MDA-MB-231 cells. The results revealed that knockdown of kin17 inhibited proliferation and promoted apoptosis of MDA-MB-231 cells, and suggested a poly (adenosine diphosphate-ribose) polymerase-related mechanism behind the apoptosis of the cells. These findings suggested that kin17 could become a novel target for breast cancer therapy.

Surgical options for male breast cancer

BACKGROUND

Male breast cancer (MBC) is a rare disease for which no randomised controlled trials (RCT) have been conducted to determine optimal surgical management. The available data have been reviewed to identify reasonable options and reveal areas in need of investigation.

METHODS

All published series on the surgical management of MBC have been reviewed to determine approaches to treatment of the primary, the breast and the axilla together with the psychological sequelae of surgery.

FINDINGS

Mastectomy is still the major surgical offer but a convincing case can be made for the use of neoadjuvant endocrine treatment in order to facilitate breast conserving surgery. Sentinel node biopsy has been successfully used for staging MBC although nomograms for prediction of nodal status are inadequately calibrated. There are psychological sequelae of mastectomy in males and as yet no evidence that the needs of those with MBC are being met.

CONCLUSIONS

Collaborative studies are required so that men can participate in meaningful RCTs to provide an evidence-based rational foundation for the surgery of MBC.

Improved diagnostics and change of tumour characteristics in breast cancer: a retrospective study over two decades

BACKGROUND

Generally, screen-detected cancers have more favourable tumour characteristics than clinically detected or symptomatic cancers. Less is known, whether the tumour characteristics of breast cancer have changed over time into more favourable in general and whether the changes have been similar in all ages.

MATERIAL AND METHODS

The aim of this study was to explore the change of breast cancer characteristics in parallel to the implementation of modern diagnostic methods in three age groups over four 5-year time periods between 1992 and 2011. The data from 942 primary breast cancers in one university hospital district in Finland were combined with data from the Finnish Cancer Registry and the Mass Screening Registry. The association of favourable tumour characteristics with time period, age group and diagnostic methods was explored.

RESULTS

The most discernible secular change was the increase in oestrogen (ER)-positive cancers in every consecutive time period. The risk for ER positivity in the second, third and fourth period was 2- to 2.71-fold compared to the first period. An increase in small tumours and node-negative tumours was detected during the most recent years of data collection. The secular changes were observed in all age groups; however, overall ER positivity was most frequent among women beyond screening age and small tumours among screening-aged women. The increase in small and node-negative tumours could partly be explained by the implementation of new radiological methods.

CONCLUSIONS

This study detected a secular change of tumour characteristics into more favourable irrespective of age group. If the trend continues, it seems that we are going to have a breast cancer population of mainly small ER-positive breast cancers in the future forcing to rethink the therapeutic approach.

Male breast cancer: a nation-wide population-based comparison with female breast cancer

OBJECTIVE

Describe prognostic parameters of Danish male breast cancer patients (MBCP) diagnosed from 1980-2009. Determine all-cause mortality compared to the general male population and analyze survival/mortality compared with Danish female breast cancer patients (FBCP) in the same period.

MATERIAL AND METHODS

The MBCP cohort was defined from three national registers. Data was extracted from medical journals. Data for FBCP is from the DBCG database. Overall survival (OS) was quantified by Kaplan-Meier estimates. Standardized mortality ratios (SMRs) were calculated based on mortality rate among patients relative to the mortality rate in the general population. The association between SMR and risk factors were analyzed in univariate and multivariable Poisson regression models. Separate models for each gender were used for the analyses.

RESULTS

We found a marked difference in OS for the two genders. For the total population of MBCP, 5- and 10-year survivals were 55.1% and 31.7%, respectively. For FBCP, the corresponding figures were 76.8% and 59.3%. Median age at diagnosis for FBCP was 61 years and 70 years for MBCP. By applying SMR, the difference in mortality between genders equalized and showed pronounced age-dependency. For males <40 years, SMR was 9.43 and for females 19.56 compared to SMR for males 80 + years (0.95) and females 80 + years (0.89). During the period 1980-2009, the risk of dying gradually decreased for FBCP (p < .0001). The risk 1980-1984 was 35% higher than 2005-2009 (RR 1.35). Although the risk of dying for MBCP was also lowest in 2005-2009, there was no clear tendency (p = .1439). The risk was highest in 1990-1994 (RR =2.48).

CONCLUSION

We found better OS for FBCP than for MBCP. But SMR showed similar mortality rate for the two genders, except for very young FBCP, who had higher SMR. Furthermore, significantly improved survival over time for FBCP was observed, with no clear tendency for MBCP.

The occurrence of fractures after adjuvant treatment of breast cancer: a DBCG register study

BACKGROUND

Adjuvant treatment in breast cancer patients especially with aromatase inhibitors (AIs) has adverse effects on bone metabolism resulting in an increased occurrence of fractures. In order to demonstrate this occurrence, long-term follow-up studies are necessary. From several national registries in Denmark, it is possible to link data from different sources and analyze this issue.

METHODS

A study cohort of 68,842 breast cancer patients prospectively diagnosed and registered in the Danish Breast Cancer Cooperative Group's database during the period 1995-2012 formed the basis of the analysis. These data were matched with data on all types of fractures from the Danish National Patient Register and vital data from the Danish Civil Registration System.

RESULTS

After data cleaning 66,502 patients were available for analysis and 16,360 of these had incurred 20,341 fractures with 13,182 patients having just one fracture. These fractures were distributed over 214 specific fracture sites. An extended multivariable Cox regression model revealed significant association between the occurrence of fractures and age, menopause, Charlson comorbidity index (CCI) and endocrine therapy such that late menopause and tamoxifen treatment were associated with a lower occurrence and AI treatment, age and CCI were associated with a higher occurrence of fractures.

CONCLUSION

Before advising adjuvant therapy with AIs fragile patients with chronic diseases should receive special attention in order to reduce the incidence of fractures in this vulnerable group of patients.

Forty years of landmark trials undertaken by the Danish Breast Cancer Cooperative Group (DBCG) nationwide or in international collaboration

BACKGROUND

Over the past 40 years the Danish Breast Cancer Cooperative Group (DBCG) has made significant contributions to improve outcome and to make treatment of patients with early breast cancer more tolerable through nationwide and international trials evaluating loco-regional and systemic treatments. These trials have been instrumental to establish standards for the treatment of early breast cancer.

METHODS

The DBCG 82 trials had a global impact by documenting that the significant gain in loco-regional recurrence from postmastectomy radiation added to systemic therapy was associated with a reduction in distant recurrence and mortality in high-risk pre- and postmenopausal patients. The DBCG trials comparing breast conserving surgery and radiotherapy with mastectomy and more recently the trial of internal mammary node irradiation also had a major impact of practice. The trials initiated by the DBCG 40 years ago on tamoxifen and cyclophosphamide based chemotherapy became instrumental for the development of adjuvant systemic therapy not only due to their positive results but by sharing these important data with other members of the Early Breast Cancer Trialist' Collaborative Group (EBCTCG). Trials from the DBCG have also been important for highlighting the relative importance of anthracyclines and taxanes in the adjuvant setting. Furthermore, DBCG has made a major contribution to the development of aromatase inhibitors and targeted adjuvant treatment for human epidermal growth factor receptor 2 positive breast cancers.

RESULTS

The substantial impact of these treatment improvements is illustrated by a 46.7% 10-year overall survival of early breast cancer patients treated in 1978-1987 compared to 71.5% for patients treated 2008-2012.

CONCLUSIONS

The trials conducted and implemented by the DBCG appear to have a major impact on the substantial survival improvements in breast cancer.

Clinical and molecular characterization of BRCA-associated breast cancer: results from the DBCG

BACKGROUND

In breast cancer (BC) patients a cancer predisposing BRCA1/2 mutation is associated with adverse tumor characteristics, risk assessment and treatment allocation. We aimed to estimate overall- (OS) and disease-free survival (DFS) according to tumor characteristics and treatment among women who within two years of definitive surgery for primary BC were shown to carry a mutation in BRCA1/2 .

MATERIAL AND METHODS

From the clinical database of the Danish Breast Cancer Group we included 141 BRCA1 and 96 BRCA2 BC patients. Estrogen receptor and HER2 status were centrally reviewed on paraffin-embedded tumor tissue. Information on risk reducing surgery was obtained from the Danish Pathology and Patient Registries and included as time-dependent variables in Cox proportional hazard models.

RESULTS

Ten-year OS and DFS for BRCA1 BC patients were 78% (95% CI 69-85) and 74% (95% CI 64-81). Ten-year OS and DFS for BRCA2 BC were 88% (95% CI 78-94) and 84% (95% CI 74-91). BRCA1 BC patients as compared to BRCA2 BC patients had a higher risk of BC relapse or non-breast cancer within ten years of follow-up, independent of ER status (adjusted HR 2.78 95% CI 1.28-6.05, p = .01), but BRCA mutation was not associated with OS (adjusted HR 1.98, 95% CI 0.87-4.52, p = .10). In multivariate analysis, including both BRCA1 and BRCA2 carriers, no chemotherapy was associated with a higher risk of death (adjusted OS HR 3.58, 95% CI 1.29-9.97, p = .01) and risk reducing contralateral mastectomy (RRCM) was associated with a significantly reduced risk of death (adjusted OS HR 0.42, 95% CI =0.21-0.84, p = .01).

CONCLUSION

Difference in OS between BRCA1 and BRCA2 BC patients could be ascribed to tumor-biology. BRCA1 BC patients may have a shorter ten-year DFS than BRCA2 BC patients. Chemotherapy and risk reducing contralateral mastectomy reduce mortality for both BRCA1 and BRCA2 BC patients.

The clinical database and implementation of treatment guidelines by the Danish Breast Cancer Cooperative Group in 2007-2016

BACKGROUND

Since 40 years, Danish Breast Cancer Cooperative Group (DBCG) has provided comprehensive guidelines for diagnosis and treatment of breast cancer. This population-based analysis aimed to describe the plurality of modifications introduced over the past 10 years in the national Danish guidelines for the management of early breast cancer. By use of the clinical DBCG database we analyze the effectiveness of the implementation of guideline revisions in Denmark.

METHODS

From the DBCG guidelines we extracted modifications introduced in 2007-2016 and selected examples regarding surgery, radiotherapy (RT) and systemic treatment. We assessed introduction of modifications from release on the DBCG webpage to change in clinical practice using the DBCG clinical database.

RESULTS

Over a 10-year period data from 48,772 patients newly diagnosed with malignant breast tumors were entered into DBCG's clinical database and 42,197 of these patients were diagnosed with an invasive carcinoma following breast conserving surgery (BCS) or mastectomy. More than twenty modifications were introduced in the guidelines. Implementations, based on prospectively collected data, varied widely; exemplified with around one quarter of the patients not treated according to a specific guideline within one year from the introduction, to an almost immediate full implantation.

CONCLUSIONS

Modifications of the DBCG guidelines were generally well implemented, but the time to full implementation varied from less than one year up to around five years. Our data is registry based and does not allow a closer analysis of the causes for delay in implementation of guideline modifications.

Pre-diagnostic plasma enterolactone concentrations and breast cancer prognosis among postmenopausal women - The Danish Diet, Cancer and Health cohort

BACKGROUND & AIMS

High intakes of the phytoestrogen lignans and high blood concentrations of its main biomarker, enterolactone, has been associated with a better breast cancer prognosis. We investigated the association between pre-diagnostic plasma concentrations of enterolactone and breast cancer prognosis (i.e. recurrence, breast cancer-specific mortality and all-cause mortality).

METHODS

Plasma and data was available from the Danish Diet, Cancer and Health cohort. Information on treatment and clinical characteristics from registries and clinical databases and both pre-diagnostic and diagnostic plasma measurement of enterolactone on a sub-set. Enterolactone was quantified in plasma using a high-throughput LC-MS/MS method. We followed 1457 breast cancer cases from date of diagnosis and until censoring or end-of-follow-up (median 9 years), during this time 404 died (250 of breast cancer) and 267 experienced recurrence. Cox proportional hazards models were used to estimate hazard ratios (HR) with 95% confidence intervals (CI).

RESULTS

Plasma enterolactone were borderline significantly associated with lower breast cancer-specific mortality (HR_doubling = 0.93, 95% CI:0.86, 1.00, P = 0.0501), but not associated with all-cause mortality (HR_doubling = 0.95, 95% CI:0.89, 1.01) and recurrence (HR_doubling = 0.96, 95% CI: 0.89, 1.04) in the models adjusted for smoking, schooling, BMI, physical activity and use of menopausal hormones. Adjusting further for clinical characteristics and treatment did not change the results considerably. In the sensitivity analyses, an inverse association was found with all-cause and breast cancer-specific mortality for those where blood was collected ≤5 years before diagnosis.

CONCLUSIONS

Overall, no clear association was found between pre-diagnostic plasma concentrations of enterolactone and breast cancer prognosis.

Failure pattern and survival after breast conserving therapy. Long-term results of the Danish Breast Cancer Group (DBCG) 89 TM cohort

Based on the results from the DBCG 82 trial, breast conserving therapy (BCT) has been implemented as standard in Denmark since 1989, and today constitutes more than 70% of the primary treatment. Our aim was to evaluate the implementation of BCT as a routine procedure in patients treated according to the DBCG 89 program and compare recurrence pattern and survival both overall and when separated in age groups, with the results from the randomized DBCG 82 TM trial.

MATERIAL AND METHODS

A total of 1847 patients treated between 1989 and 1999 were included in a retrospective population-based cohort study. Data from the DBCG database were completed via search through the Danish Pathology Data Bank and medical records.

RESULTS

Median follow-up time was 17 years. At 20 years the cumulative incidences of local recurrence (LR) and disease-specific mortality (DSM) were 15.3% and 25.8%, respectively. Twenty-year overall survival (OS) and recurrence-free survival were 63.7% and 43.1%, respectively. Subdivided by age groups cumulative incidences at 20 years were LR: 18.9%, 10.5% and 12.4%, and DSM: 28.9%, 18.9% and 28.4% in young (≤45 years), middle-aged (46-55 years) and older (≥56 years) women, respectively. In an adjusted analysis age maintained a significant and independent effect on both LR and DSM.

CONCLUSION

The DBCG 82 TM program was successfully implemented. The women treated with BCT in the DBCG 89 program displayed equal failure pattern and improved survival in comparison with women from the DBCG 82 TM protocol. Occurrence of first failure and mortality varied with age; demonstrated by increased risk of LR, DM and DSM in the young patients and increased risk of DM and DSM in the older patients, compared to the middle-aged patients.