Nationwide population-based study of trends and regional variation in breast-conserving treatment for breast cancer

Evaluating Surgical Outcomes Between Estrogen Receptor Positive Invasive Lobular and Invasive Ductal Carcinoma of the Breast-A Propensity Matched Analysis

INTRODUCTION

Invasive lobular carcinoma (ILC) contributes significantly to the global cancer burden and is the most common of the histological "special types" of breast cancer. ILC has unique features setting it apart from the more common invasive ductal carcinoma (IDC). Despite differences, treatment algorithms do not consider histological differences.

AIM

To determine the differences in treatment and outcomes of ILC relative to IDC in a strict case-matched cohort study at a tertiary referral, specialist, breast cancer center.

METHODS

All Estrogen receptor positive (ER+) ILCs from 1999 to 2015 were matched for; age, tumor size, grade, PR/HER2 status, nodal stage and metastases with ER+ IDCs from the same period. Surgical and systemic treatments were assessed along with overall (OS) and disease-free survival (DFS).

RESULTS

762 cases in total were analyzed (1:1 matching; ILC:IDC). ILC cases were more often treated with mastectomy (37.5% vs. 28.6%, P .009) and those who received breast conserving surgery (BCS) more often had an incomplete resection (30.2% vs. 19.6%, P .01). IDC were more often treated with NACT (5.5% vs. 14.4%, P < .001). Mean DFS were similar between ILC and IDC; 148.3 vs. 141.4 months (P .112) but OS was significantly longer in the ILC group; 165.7 vs. 134 months (P .002). This trend was consistent among the subset of patients undergoing BCS. For ILC undergoing BCS, mean DFS was 129.8 vs. 128.3 months for IDC (P .418) and OS was 155.4 and 110.7 months respectively (P < .001). Incomplete resection at the time of index surgery did not alter the disease free or overall survival in either the ILC or IDC patients to a level that reached statistical significance.

CONCLUSION

In this cohort study, the strict matching of ILC and IDCs for a number of prognostic indicators, demonstrates the impact of lobular histology with a clarity not previously observed. ILCs have comparable survival outcomes to patients with IDC but at the expense of more extensive index and revisional surgery. There is a need for awareness of these facts among surgeons and patients for optimal treatment prioritization and provision.

Clinical Features and Prognoses of Patients With Breast Cancer Who Underwent Surgery

Importance

Breast cancer (BC) remains a pervasive malignant neoplasm worldwide, with increasing incidence. However, there are a scarcity of studies examining the clinical characteristics and prognosis of Chinese patients with BC who have undergone surgery.

Objective

To evaluate overall survival (OS) and disease-free survival (DFS) in patients with surgically treated BC in China, focusing on histopathology and surgical approach.

Design, Setting, and Participants

This cohort study included a retrospective review of the medical records of patients with unilateral BC who underwent surgery between January 2009 and September 2017, with a median follow-up time of 7.69 years. Clinical features were extracted from these records, and survival analysis was performed. Data analysis was conducted in March 2023.

Main Outcomes and Measures

Patients' OS and DFS.

Results

The study included 14 782 patients (14 724 [99.6%] female patients; mean [SD] age, 51.6 [10.9] years). Invasive ductal carcinoma (IDC) was the most prevalent type, observed in 12 671 patients (85.6%). Stages 0, I, II, III, and IV accounted for 6.4% (919 patients), 32.0% (4579 patients), 40.5% (5791 patients), 20.2% (2896 patients), and 0.9% (126 patients) of cases, respectively. Hormone receptor (HR) positivity was observed in 10 241 patients (75.1%), and 3665 (29.1%) tested positive for ERBB2 (formerly HER2/neu). The HR-negative-ERBB2-negative, HR-negative-ERBB2-positive, HR-positive-ERBB2-negative, and HR-positive-ERBB2-positive subtypes constituted 13.3% (1666 patients), 12.7% (1595 patients), 57.8% (7251 patients), and 16.2% (2034 patients) of cases, respectively. Breast-conserving surgery (BCS) was performed in 2884 patients (19.5%). The 5-year and 10-year OS rates were 92.9% (13 689 of 14 732) and 87.4% (3287 of 3760), while the 5-year and 10-year DFS rates were 89.0% (12 916 of 14 512) and 82.9% (3078 of 3713), respectively. Multivariate analysis found that for patients with IDC, age, BCS, invasive tumor size, tumor grade, lymphovascular invasion (LVI), the number of lymph node metastases (LNMs), distant metastasis, Ki67, and HR status were associated with OS, whereas invasive tumor size, tumor grade, LVI, the number of LNMs, HR status, and ERBB2 status were associated with DFS. After propensity score matching, BCS was equivalent to mastectomy with respect to survival in patients with IDC.

Conclusions and Relevance

This cohort study of patients with BC who underwent surgery in China provides valuable insights into the histopathological characteristics and survival outcomes of this population. The diverse histopathological features emphasize the necessity for customized treatment strategies. The relatively low BCS rate in the study population suggests the need for heightened awareness and adoption of this approach, considering its potential advantages for survival.

A large single-center prospective study to investigate the factors influencing the choice of breast-conserving surgery versus mastectomy in Chinese women with early breast cancer

BACKGROUND

Compared to mastectomy, breast-conserving surgery (BCS) provides the same survival rate and a higher quality of life for patients with early breast cancer (EBC). However, Chinese women with EBC are known to have a low BCS rate. A large prospective cohort study was conducted to investigate the factors influencing the choice of BCS in this population.

METHODS

In 2017, all women with unilateral EBC and eligible for BCS at our institution were enrolled. Before surgery, the patient's trust in the surgeon and her perceived strength of the surgeon's recommendation of BCS were measured through an in-person interview and validated ad hoc questionnaire. Multivariate logistic regressions on BCS procedure vs. mastectomy were used to estimate the odds ratio (OR).

RESULTS

One thousand one hundred thirty-six patients enrolled at analysis had an average age of 51.8 and tumor size of 2.4 cm. 19.9% of patients had BCS. The "strong" level of trust in the surgeon was significantly associated with BCS with an OR of 2.944 (p<0.001) when compared to the "average or under" trust. The "strong" and "moderate" strengths in surgeon recommendation for BCS were also found to be significantly associated with the BCS procedure with ORs of 12.376 (p <0.001) and 1.757 (p =0.040), respectively, compared to the "neutral or dissuaded" strength.

CONCLUSIONS

Stronger trust in surgeons and BCS recommendation by surgeons are associated with a higher rate of BCS in Chinese women with EBC. Interventional trials are needed to confirm this finding.

Yield of Surveillance Imaging After Mastectomy With or Without Reconstruction for Patients With Prior Breast Cancer: A Systematic Review and Meta-analysis

IMPORTANCE

A discrepancy on current guidelines and clinical practice exists regarding routine imaging surveillance after mastectomy, mainly regarding the lack of adequate evidence for imaging in this setting.

OBJECTIVE

To investigate the usefulness of imaging surveillance in terms of cancer detection and interval cancer rates after mastectomy with or without reconstruction for patients with prior breast cancer.

DATA SOURCES

A comprehensive literature search was conducted in 3 electronic databases-PubMed, ISI Web of Science, and Scopus-without year restriction. References from relevant reviews and eligible studies were also manually searched.

STUDY SELECTION

Eligible studies were defined as those conducting surveillance imaging (mammography, ultrasonography, or magnetic resonance imaging [MRI]) of patients with prior breast cancer after mastectomy with or without reconstruction that presented adequate data to calculate cancer detection rates for each surveillance method.

DATA EXTRACTION AND SYNTHESIS

Independent data extraction by 2 investigators with consensus on discrepant results was performed. A quality assessment of studies was performed using the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2) template. The generalized linear mixed model framework with both fixed-effects and random-effects models was used to meta-analyze the proportion of cases across studies including 3 variables: surveillance method, reconstruction after mastectomy, and surveillance measure.

MAIN OUTCOMES AND MEASURES

Three outcome measures were calculated for each eligible study and each surveillance imaging method within studies: overall cancer detection (defined as ipsilateral cancer, both palpable and nonpalpable) rate per 1000 examinations, clinically occult (nonpalpable) cancer detection rate per 1000 examinations, and interval cancer rate per 1000 examinations.

RESULTS

In total, 16 studies were eligible for the meta-analysis. The pooled overall cancer detection rates per 1000 examinations were 1.86 (95% CI, 1.05-3.30) for mammography, 2.66 (95% CI, 1.48-4.76) for ultrasonography, and 5.17 (95% CI, 1.49-17.75) for MRI. For mastectomy without reconstruction, the rate of clinically occult (nonpalpable) cancer per 1000 examinations (2.96; 95% CI, 1.38-6.32) and the interval cancer rate per 1000 examinations (3.73; 95% CI, 0.84-3.98) were lower than the overall cancer detection rate (including both palpable and nonpalpable lesions) per 1000 examinations (6.41; 95% CI, 3.09-13.25) across all imaging modalities. The interval cancer rate per 1000 examinations for mastectomy with reconstruction (3.73; 95% CI, 0.41-2.73) was comparable to the pooled cancer detection rate per 1000 examinations (4.73; 95% CI, 2.32-9.63) across all imaging modalities. In all clinical scenarios and imaging modalities, lower rates of clinically occult cancer compared with cancer detection rates were observed.

CONCLUSIONS AND RELEVANCE

Lower detection rates of clinically occult-compared with overall-cancer across all 3 imaging modalities challenge the use of imaging surveillance after mastectomy, with or without reconstruction. Findings suggest that imaging surveillance in this context is unnecessary in clinical practice, at least until further studies demonstrate otherwise. Future studies should consider using the clinically occult cancer detection rate as a more clinically relevant measure in this setting.

Predictors of delayed breast reconstruction in the Netherlands: a 5-year follow-up study in stage I-III breast cancer patients

PURPOSE

Delayed breast reconstruction (DBR) is a valid option for postmastectomy breast cancer patients who have a desire for breast reconstruction but are not considered suitable for immediate breast reconstruction (IBR). The objective of this study was to investigate the clinical practice and predictors of the use of DBR in the Netherlands.

METHODS

Stage I-III breast cancer patients diagnosed from January to March 2012 and treated with mastectomy were selected from the Netherlands Cancer Registry. Routinely collected patient, tumor, treatment and hospital characteristics were complemented with data about DBR up to 2018. Multivariable logistic regression analyses were performed to identify factors independently associated with postmastectomy DBR. Factors associated with time to DBR were identified through Cox regression analyses.

RESULTS

Of all patients who underwent mastectomy (n = 1,415), 10.2% underwent DBR. DBR patients more often received autologous reconstruction compared to IBR patients (37.5% vs 6.2%, p < 0.001). Age below 50 years (age < 35 OR 15.55, age 35-49 OR 4.18) and neoadjuvant and adjuvant chemotherapy (OR 2.59 and OR 2.83, respectively) were significantly associated with DBR. Mean time to DBR was 2.4 years [range 1-6 years]. Time to DBR was significantly associated with age < 35 years (HR 2.22), and a high hospital volume (HR 1.87).

DISCUSSION

The use of DBR after mastectomy could not be fully explained by age below 50 years, chemotherapy, and hospital volume. Treatment with radiotherapy and adjuvant chemotherapy increased time to DBR. More information about patient preferences is needed to understand the use and timing of reconstruction.

The association of socioeconomic status on treatment strategy in patients with stage I and II breast cancer in the Netherlands

Background

Previous studies have shown that socioeconomic status (SES) influences breast cancer therapy. However, these studies were performed in countries with unequal access to healthcare. Therefore, the aim of this study is to investigate whether SES also contributes to the likelihood of receiving a certain therapy in the Netherlands, a country with supposedly equal access to healthcare.

Materials and methods

From the Netherlands Cancer Registry, 105,287 patients with newly diagnosed stage I or II breast cancer diagnosed between 2011 and 2018 were selected for analysis. SES was calculated from the average incomes of each postal code, which were divided into 10 deciles. Primary outcome was the effect of SES on the likelihood of undergoing surgery and secondary outcome was the effect of SES on the likelihood of the type of surgery. Both outcomes were corrected for patient, tumor, and hospital characteristics and were expressed as odds ratio (OR) with 95% confidence interval (CI).

Results

SES did not affect the likelihood of a breast cancer patient to undergo surgery (OR 1.00 per 10% stratum). In contrast, increased age and higher tumor stage were the most important factors determining whether patients underwent surgery.

Patients with higher SES were less likely to undergo mastectomy (OR 0.98). Additionally, more recently diagnosed patients were less likely to undergo mastectomy (OR 0.93 per year) while patients with higher tumor stage were more likely to undergo mastectomy (OR 3.42).

Conclusion

SES does not affect whether a patient undergoes surgery; however, higher SES increased the likelihood of BCT.

Breast surgery for young women with early-stage breast cancer: Mastectomy or breast-conserving therapy?

Whether breast-conserving therapy (BCT) should be chosen as a local treatment for young women with early-stage breast cancer is controversial. This study compared the survival benefits of BCT or mastectomy in young women under 40 with early-stage breast cancer and further explored age-stratified outcomes. This study investigated whether there is a survival benefit when young women undergo BCT compared with mastectomy.The characteristics and prognosis of white women under 40 with stage I-II breast cancer from 1988 to 2016 were analyzed using the Surveillance, Epidemiology, and End Results (SEER) database. These women were either treated with BCT or mastectomy. The log-rank test of the Kaplan-Meier survival curve and Cox proportional risk regression model were used to analyze the data and survival. The analysis was stratified by age (18-35 and 36-40 years).A total of 23,810 breast cancer patients were included, of whom 44.9% received BCT and 55.1% underwent mastectomy, with a median follow-up of 116 months. Patients undergoing mastectomy had a higher tumor burden and younger age. By the end of the 20th century, the proportion of BCT had grown from nearly 35% to approximately 60%, and then gradually fell to 35% into the 21st century. Compared with the mastectomy group, the BCT group had improved breast cancer-specific survival (BCSS) (hazard ratio [HR] 0.917; 95% CI, 0.846-0.995, P = .037) and overall survival (OS) (HR 0.925; 95% CI, 0.859-0.997, P = .041). In stratified analysis according to the different ages, the survival benefit of BCT was more pronounced in the slightly older (36-40 years) group while there was no significant survival difference in the younger group (18-35 years).In young women with early-stage breast cancer, BCT showed survival benefits that were at least no worse than mastectomy, and these benefits were even better in the 36 to 40 years age group. Young age may not be a contraindication for BCT.

Assessment of Breast Cancer Surgery in Manitoba: A Descriptive Study

BACKGROUND

Variation in breast cancer surgical practice patterns can lead to poor clinical outcomes. It is important to measure and reduce variation to ensure all women diagnosed with breast cancer receive equitable, high-quality care. A population-based assessment of the variation in breast cancer surgery treatment and quality has never been conducted in Manitoba. The objective of this study was to assess the variation in surgical treatment patterns, quality of care, and post-operative outcomes for women diagnosed with invasive breast cancer.

METHODS

This descriptive study used data from the Manitoba Cancer Registry, Hospital Discharge Abstracts Database, Medical Claims, Manitoba Health Insurance Registry, and Statistics Canada. The study included women in Manitoba aged 20+ and diagnosed with invasive breast cancer between 1 January 2010 and 31 December 2014.

RESULTS

Axillary lymph node dissection (ALND) for node-negative disease ranged from 11.8% to 33.3%, timeliness (surgery within 30 days of consult) ranged from 33.3% to 60.2%, and re-excision ranged from 14.7% to 24.6% between health authorities. Women who underwent breast-conserving surgery had the shortest median length of stay and women who underwent mastectomy with immediate reconstruction had the longest median length of stay. In-hospital post-operative complications were higher among women who received mastectomy with immediate reconstruction (9.9%).

CONCLUSION

Variation in surgical treatment, quality, and outcomes exist in Manitoba. The findings from this study can be used to inform cancer service delivery planning, quality improvement efforts, and policy development. Influencing data-driven change at the health system level is paramount to ensuring Manitobans receive the highest quality of care.

Effect of the COVID-19 Pandemic on Surgical Breast Cancer Care in the Netherlands: A Multicenter Retrospective Cohort Study

Background

Coronavirus disease 2019 (COVID-19) has put a strain on regular healthcare worldwide. In the Netherlands, the national screening programs, including for breast cancer, were halted temporarily. This posed a challenge to breast cancer care, because ∼40% of cases are detected through national screening. Therefore, the aim of the present study was to evaluate the effects of the COVID-19 pandemic on the surgical care of patients with breast cancer in the Netherlands.

Materials and Methods

The present multicenter retrospective cohort study investigated the effects of COVID-19 on patients with breast cancer who had undergone surgery from March 9 to May 17, 2020. The primary endpoints were the number of surgical procedures performed during the study period, tumor characteristics, surgery type, and route of referral. The secondary endpoint was the incidence of postoperative complications during the study period.

Results

A total of 217 consecutive patients with breast cancer requiring surgery were included. We found an overall decrease in the number of patients with breast cancer who were undergoing surgery. The most significant decline was seen in surgery for T1-T2 and N0 tumors. A decline in the number of referrals from both the national screening program and general practitioners was observed. The incidence of postoperative complications remained stable during the study period.

Conclusions

The temporary halt of the national screening program for breast cancer resulted in fewer surgical procedures during the study period and a pronounced decrease in surgery of the lower tumor stages.

Optimization of Wire-guided Technique With Bracketing Reduces Resection Volumes in Breast-conserving Surgery for Early Breast Cancer

BACKGROUND

Wire-guided localization (WGL) of early breast cancer can be facilitated using multiple wires, which is called bracketing wire-guided localization (BWL). The primary aim of this study is to compare BWL and conventional WGL regarding minimization of resection volumes without compromising margin status. Secondly, BWL is evaluated as an alternative method for intraoperative ultrasound (US) guidance in poorly definable breast tumors on US.

PATIENTS AND METHODS

In this retrospective cohort study, patients with preoperatively diagnosed breast cancer undergoing wide local excision between January 2016 and December 2018 were analyzed. Patients with multifocal disease or neoadjuvant treatment were excluded from this study. Optimal resection with minimal healthy breast tissue removal was assessed using the calculated resection ratio (CRR).

RESULTS

BWL was performed in 17 (9%) patients, WGL in 44 (22%), and US in 139 (70%). The rate of negative margins was comparable in all 3 groups. The CRR was significantly smaller for BWL (0.6) than WGL (1.3) in tumors larger than 1.5 cm. Additionally, BWL (0.8) led to smaller CRRs than US (1.7). This could be explained by the high number of small tumors (≤ 1.5 cm) in the US group for which greater CRRs are obtained than for large tumors (> 1.5 cm) (1.9 vs. 1.4; P = .005).

CONCLUSION

For breast tumors larger than 1.5 cm, BWL achieves more optimal resection volumes without compromising margin status compared with WGL. Moreover, BWL seems a suitable alternative to US in patients with poorly ultrasound-visible breast tumors and patients with a small tumor in a (large) breast.

The Value of Repeated Breast Surgery as a Quality Indicator in Breast Cancer Care

Breast-conserving surgery, a major achievement in surgical oncology, has allowed an increasing number of breast cancer patients to avoid the mutilation of mastectomy. However, mastectomy still is performed in certain circumstances although breast-conserving surgery would be equally safe. Many reasons, including patients' and surgeons' personal motivations, influence the decision-making process before the final choice between breast preservation and mastectomy. The importance of quality measurement and reporting in medicine is increasingly recognized, and breast surgery is no exception. The substantial variability of re-excision rates for positive surgical margins after a first attempt at breast-conserving surgery suggests that improvement is possible. Therefore, the re-excision rate has been proposed as a quality metric for assessing and comparing the performance of different institutions. Indeed, re-excision rates can be reduced by actionable factors such as accurate preoperative local staging, localization of occult lesions, and intraoperative assessment of the oriented specimen. However, equally important non-actionable risk factors pertaining the biology, detectability, and resectability of the tumor also should be taken into account. Therefore, if the re-excision rate has to be used as a performance indicator of breast surgical care, critical interpretation of results with accurate case-mix adjustment are mandatory, and reasonable targets must be appropriately set so that surgeons treating patients at higher risk of positive margins are not unduly penalized.

Different statistical techniques dealing with confounding in observational research: measuring the effect of breast-conserving therapy and mastectomy on survival

PURPOSE

Propensity trimming, hierarchical modelling and instrumental variable (IV) analysis are statistical techniques dealing with confounding, cluster-related variation or confounding by severity. This study aimed to explain (dis)advantages of these techniques in estimating the effect of breast-conserving therapy (BCT) and mastectomy on 10-year distant metastasis-free survival (DMFS).

METHODS

All women diagnosed in 2005 with primary T1-2N0-1 breast cancer treated with BCT or mastectomy were selected from the Netherlands Cancer Registry. We used multivariable Cox regression to correct for confounding. Propensity trimming was used to create a more homogeneous population for which the treatment choice was not self-evident. Hospital of surgery was used as hierarchical level to handle hospital-related variation, and as IV to deal with unmeasured confounding.

RESULTS

Multivariable Cox regression showed higher 10-year DMFS for BCT than mastectomy [HR 0.70 (95% CI 0.60-82)]. Propensity trimming on the 10-90th and the 20-80th percentile of the propensity score distribution and hierarchical modelling showed similar HRs. IV analysis showed no significant difference between BCT and mastectomy.

CONCLUSION

Unmeasured confounding is very difficult to eliminate in observational research. We cannot conclude that BCT or mastectomy has a causal relationship with 10-year DMFS. It is crucial to critically evaluate all model's assumptions, and to be careful in drawing firm conclusions.

Predicting the risk of locoregional recurrence after early breast cancer: an external validation of the Dutch INFLUENCE-nomogram with clinical cancer registry data from Germany

Purpose

Follow-up after breast cancer treatment aims for an early detection of locoregional breast cancer recurrences (LRR) to improve the patients’ outcome. By estimating individual’s 5-year recurrence-risks, the Dutch INFLUENCE-nomogram can assist health professionals and patients in developing personalized risk-based follow-up pathways. The objective of this study is to validate the prediction tool on non-Dutch patients.

Material and methods

Data for this external validation derive from a large clinical cancer registry in southern Germany, covering a population of 1.1 million. Patients with curative resection of early-stage breast cancer, diagnosed between 2000 and 2012, were included in the analysis (n = 6520). For each of them, an individual LRR-risk was estimated by the INFLUENCE-nomogram. Its predictive ability was tested by comparing estimated and observed LRR-probabilities using the Hosmer–Lemeshow goodness-of-fit test and C-statistics.

Results

In the German validation-cohort, 2.8% of the patients developed an LRR within 5 years after primary surgery (n = 184). While the INFLUENCE-nomogram generally underestimates the actual LRR-risk of the German patients (p < 0.001), its discriminative ability is comparable to the one observed in the original Dutch modeling-cohort (C-statistic German validation-cohort: 0.73, CI 0.69–0.77 vs. C-statistic Dutch modeling-cohort: 0.71, CI 0.69–0.73). Similar results were obtained in most of the subgroup analyses stratified by age, type of surgery and intrinsic biological subtypes.

Conclusion

The outcomes of this external validation underline the generalizability of the INFLUENCE-nomogram beyond the Dutch population. The model performance could be enhanced in future by incorporating additional risk factors for LRR.

The 21-gene recurrence score and effects of adjuvant radiotherapy after breast conserving surgery in early-stage breast cancer

Aim: To investigate the associations with the 21-gene recurrence score (RS) and effect of adjuvant radiotherapy (RT) for early-stage breast cancer after breast conserving surgery. Methods: We included 13,246 patients in the SEER database. Results: Patients with a higher RS were independently related to nonreceipt of RT (p < 0.001). In both the traditional and Trial Assigning Individualized Options for Treatment (TAILORx) RS cut-offs, the receipt of RT was not related to better breast cancer-specific survival in low- and high-risk RS groups, but was independently related to better breast cancer-specific survival in intermediate-risk RS group before (p = 0.029) and after (p = 0.001) propensity score matching. Conclusion: The 21-gene-RS may impact the decision-making of adjuvant RT in early-stage breast cancer after breast conserving surgery. The survival benefit of adjuvant RT may be limited to patients with intermediate-risk RS.