Evaluation of the Implementation of the Dutch Breast Cancer Surveillance Decision Aid including Personalized Risk Estimates in the SHOUT-BC Study: A Mixed Methods Approach.

BACKGROUND: To improve Shared decision-making (SDM) regarding personalized post-treatment surveillance, the Breast Cancer Surveillance Decision Aid (BCS-PtDA), integrating personalized risk information, was developed and implemented in eight hospitals. The aim of this mixed-methods study was to (1) assess the implementation and participation rates, (2) identify facilitators and barriers for use by health care professionals (HCPs), (3) quantify the observed level of SDM, and (4) evaluate risk communication and SDM application in consultations. METHODS: Implementation and participation rates and patients' BCS-PtDA use were calculated using hospital registry data and BCS-PtDA log data. HCPs' perspective on facilitators and barriers were collected using the MIDI framework. Observed SDM levels in consultation transcripts were quantified using the OPTION-5 scale. Thematic analysis was performed to assess consultation content. RESULTS: The average PtDA implementation and participation rates were, respectively, 26% and 61%. HCPs reported that the PtDA supported choice awareness. Reported barriers for implementation were mainly increased workload and a lack of perceived benefits. The consultation analysis (n = 64) showed patients were offered a choice, but deliberation was lacking. Risk communication was generally adequate. DISCUSSION: When the BCS-PtDA was used, patients were clearly given a choice regarding their post-treatment surveillance, but information provision and SDM application can be improved.

De-escalation of axillary treatment in the event of a positive sentinel lymph node biopsy in cT1-2 N0 breast cancer treated with mastectomy: nationwide registry study (BOOG 2013-07).

BACKGROUND: Trials have demonstrated the safety of omitting completion axillary lymph node dissection in patients with cT1-2 N0 breast cancer operated with breast-conserving surgery who have limited metastatic burden in the sentinel lymph node. The aim of this registry study was to provide insight into the oncological safety of omitting completion axillary treatment in patients operated with mastectomy who have limited-volume sentinel lymph node metastasis. METHODS: Women diagnosed in 2013-2014 with unilateral cT1-2 N0 breast cancer treated with mastectomy, with one to three sentinel lymph node metastases (pN1mi-pN1a), were identified from the Netherlands Cancer Registry, and classified by axillary treatment: no completion axillary treatment, completion axillary lymph node dissection, regional radiotherapy, or completion axillary lymph node dissection followed by regional radiotherapy. The primary endpoint was 5-year regional recurrence rate. Secondary endpoints included recurrence-free interval and overall survival, among others. RESULTS: In total, 1090 patients were included (no completion axillary treatment, 219 (20.1%); completion axillary lymph node dissection, 437 (40.1%); regional radiotherapy, 327 (30.0%); completion axillary lymph node dissection and regional radiotherapy, 107 (9.8%)). Patients in the group without completion axillary treatment had more favourable tumour characteristics and were older. The overall 5-year regional recurrence rate was 1.3%, and did not differ significantly between the groups. The recurrence-free interval was also comparable among groups. The group of patients who did not undergo completion axillary treatment had statistically significantly worse 5-year overall survival, owing to a higher percentage of non-cancer deaths. CONCLUSION: In this registry study of patients with cT1-2 N0 breast cancer treated with mastectomy, with low-volume sentinel lymph node metastasis, the 5-year regional recurrence rate was low and comparable between patients with and without completion axillary treatment.

Predictors of re-attendance at biennial screening mammography following a false positive referral: A study among women in the south of the Netherlands.

AIM: A false positive (FP) referral after screening mammography may influence a woman's likelihood to re-attend the screening program. The impact of having a FP result in the first or subsequent screening round on re-attendance after a FP result was investigated. In addition, we aimed to study differences in re-attendance rates between women who underwent non-invasive and invasive additional examinations as part of the diagnostic work-up following a FP referral. METHODS: A consecutive series of 13,597 women with a FP referral following biennial screening mammography in the south of the Netherlands between 2009 and 2019 was included. RESULTS: The screening re-attendance rate was 81.2% after a FP referral, and 91.3% when also including women who had clinical mammographic follow-up. Women who received a FP referral in the first screening round were less likely to re-attend the screening programme in the following three years, compared to those with a FP test in any subsequent round (odds ratio (OR): 0.59, 95%-confidence interval (CI): 0.51-0.69). Women with a FP referral who underwent invasive examinations after referral were less likely to re-attend the screening programme than those who only received additional imaging (OR, 0.48; 95% CI 0.36-0.64). CONCLUSION: Women with a FP referral are less likely to re-attend the screening programme if this referral occurs at their first screening round or when they undergo invasive diagnostic workup. Hospitals and screening organizations should prioritize informing women about the importance of re-attending the programme following a FP referral.

Long-term trends in incidence, characteristics and prognosis of screen-detected and interval cancers in women participating in the Dutch breast cancer screening programme.

BACKGROUND: No studies are available in which changes over time in characteristics and prognosis of patients with interval breast cancers (ICs) and screen-detected breast cancers (SDCs) have been compared. The aim was to study these trends between 1995 and 2018. METHODS: All women with invasive SDCs (N = 4290) and ICs (N = 1352), diagnosed in a southern mammography screening region in the Netherlands, were included and followed until date of death or 31 December 2022. RESULTS: The 5-year overall survival rate of women with SDCs increased from 91.4% for those diagnosed in 1995-1999 to 95.0% for those diagnosed in 2013-2018 (P < 0.001), and from 74.8 to 91.6% (P < 0.001) in the same periods for those with ICs. A similar trend was observed for the 10-year survival rates. After adjustment for changes in tumour characteristics, the hazard ratio (HR) for overall survival was 0.47 (95% confidence interval (CI): 0.38-0.59) for women with SDCs diagnosed in the period 2013-2018, compared to the women diagnosed in the period 1995-1999. For the women with ICs this HR was 0.27 (95% CI: 0.19-0.40). CONCLUSION: The prognosis of women with ICs has improved rapidly since 1995 and is now almost similar to that of women with SDCs.

Trends in the pre-operative diagnosis and surgical management of axillary lymph node metastases in women with screen-detected breast cancer.

AIM: The aim of the current study was to investigate time-trends in pre-operative diagnosis and surgical treatment of axillary lymph node metastases in breast cancers detected at screening mammography. METHODS: We included all women who underwent screening mammography in the South of the Netherlands between 2005 and 2020. During a follow-up period of at least two years, data on clinical radiological examinations, biopsy procedures and surgical interventions were obtained. The 15 years of inclusion were divided into five cohorts of three years each. RESULTS: Of the 4049 women with invasive breast cancer, 22.1 % (896/4049) had axillary lymph node metastasis at pathology (ALN+). Percutaneous axillary biopsy was performed in 39.6 % (355/896) of these women, with the proportions of fine needle aspiration biopsy (FNAB) decreasing from 97.6 % (40/41) in 2005-2007 to 41.6 % (37/89) in 2017-2019 and core needle biopsy (CNB) rising from 2.4 % (1/41) in 2005-2007 to 58.4 % (52/89) in 2017-2019 (P < 0.001). Sensitivity of FNAB and CNB was comparable (77.4 % (188/243, 95%CI = 71%-82 %) versus 82.4 % (103/125), 95%CI = 74%-88 %) (P = 0.26). Pre-operative confirmation of ALN + by percutaneous biopsy ranged from 27.3 % (56/205) in 2011-2013 to 39.0 % (80/205) in 2017-2019, with no significant trend changes over time (P = 0.103). The proportion of ALN + women who underwent axillary lymph node dissection (ALND) decreased from 96.0 % (97/101) in 2005-2007 to 16.6 % (34/205) in 2017-2019 (P < 0.001). CONCLUSION: Pre-operative confirmation of axillary lymph node metastasis by ultrasound-guided biopsy did not rise despite the increased use of CNB at the expense of less invasive FNAB. A significant reduction in ALND was observed through the years.

Impact of the COVID-19 pandemic on breast cancer incidence and tumor stage in the Netherlands and Norway: A population-based study.

BACKGROUND: Comparing the impact of the COVID-19 pandemic on the incidence of newly diagnosed breast tumors and their tumor stage between the Netherlands and Norway will help us understand the effect of differences in governmental and social reactions towards the pandemic. METHODS: Women newly diagnosed with breast cancer in 2017-2021 were selected from the Netherlands Cancer Registry and the Cancer Registry of Norway. The crude breast cancer incidence rate (tumors per 100,000 women) during the first (March-September 2020), second (October 2020-April 2021), and Delta COVID-19 wave (May-December 2021) was compared with the incidence rate in the corresponding periods in 2017, 2018, and 2019. Incidence rates were stratified by age group, method of detection, and clinical tumor stage. RESULTS: During the first wave breast cancer incidence declined to a larger extent in the Netherlands than in Norway (27.7% vs. 17.2% decrease, respectively). In both countries, incidence decreased in women eligible for screening. In the Netherlands, incidence also decreased in women not eligible for screening. During the second wave an increase in the incidence of stage IV tumors in women aged 50-69 years was seen in the Netherlands. During the Delta wave an increase in overall incidence and incidence of stage I tumors was seen in Norway. CONCLUSION: Alterations in breast cancer incidence and tumor stage seem related to a combined effect of the suspension of the screening program, health care avoidance due to the severity of the pandemic, and other unknown factors.

Oncoplastic Breast Conserving Surgery: Is There a Need for Standardization? Results of a Nationwide Survey.

Introduction: The NABON Breast Cancer Audit showed that more than 70% of the Dutch women undergoing surgery for breast cancer maintained their breast contour by breast-conserving surgery (BCS) or by immediate reconstruction after ablative surgery. The proportion of oncoplastic surgery applied in patients undergoing breast-conserving treatment remains unknown. The aim of our study was to assess the need for standardization of oncoplastic breast-conserving surgery (OPBCS) in an attempt to enable measurement of the quality of OPBCS. Methods: To gain a better understanding of current practice in OPBCS, we sent a questionnaire to all breast surgeons in The Netherlands who are members of the breast surgery working group (n = 134). Results: A total of 60 breast surgeons, representing different hospitals in The Netherlands, responded. 61.7% of the breast surgeons performed BCS on 60-100% of their patients. 68.3% responded that BCS was performed using OPS techniques in up to 40% of their patients. OPBCS was defined as level I volume displacement by 45.2% of the breast surgeons and as BCS performed by a breast surgeon and plastic surgeon together by 32.3% of the breast surgeons. 94.5% indicated that there is a need for standardization of the definition of OPBCS in The Netherlands. Conclusion: This study demonstrates that OPBCS is a major part of daily clinical practice of Dutch breast surgeons treating BC patients. Despite this, there is no clear definition of OPS in breast-conserving treatment in The Netherlands. Only after standardization can a classification code and quality indicator be initiated for OPBCS. Ultimately, this will facilitate improvement in quality of BC care.

Effect of different quilting techniques on seroma formation after breast surgery: retrospective study.

BACKGROUND: Quilting, a technique in which skin flaps are sutured to the underlying muscle, reduces seroma after mastectomy and/or axillary lymph node dissection. The aim of this study was to assess the effect of different quilting techniques on the formation of clinically significant seroma. METHODS: This was a retrospective study including patients undergoing mastectomy and/or axillary lymph node dissection. Four breast surgeons applied the quilting technique based on their own discretion. Technique 1 was performed using Stratafix in 5-7 rows placed at 2-3 cm distance. Technique 2 was performed using Vicryl 2-0 in 4-8 rows placed at 1.5-2 cm distance. Technique 3 was performed using Vicryl 0/1 in 3 rows placed at 3-4 cm distance. Technique 4 was performed using Vicryl 0 in 4-5 rows placed at 1.5 cm distance. The primary outcome was clinically significant seroma. RESULTS: A total of 445 patients were included. Clinically significant seroma incidence was 4.1 per cent (six of 147) for technique 1, which was significantly lower than that for the other techniques (25.0 per cent (29 of 116), 29.4 per cent (32 of 109), and 33 per cent (24 of 73) for techniques 2, 3, and 4 (P < 0.001) respectively). The duration of surgery was not significantly longer for technique 1 compared with the other three techniques. The length of hospital stay, number of additional visits to the outpatient clinic, and reoperations did not differ significantly between the four techniques. CONCLUSION: Quilting using Stratafix and placing 5-7 rows with 2-3 cm distance between the stitches associates with low clinically significant seroma incidence without adverse effects.

Needs and preferences of breast cancer survivors regarding outcome-based shared decision-making about personalised post-treatment surveillance.

PURPOSE: In this study, we explored how patients experience current information provision and decision-making about post-treatment surveillance after breast cancer. Furthermore, we assessed patients' perspectives regarding less intensive surveillance in case of a low risk of recurrence. METHODS: We conducted semi-structured interviews with 22 women in the post-treatment surveillance trajectory in seven Dutch teaching hospitals. RESULTS: Although the majority of participants indicated a desire for shared decision-making (SDM) about post-treatment surveillance, participants experienced no SDM. Information provision was often suboptimal and unstructured. Participants were open for using risk information in decision-making, but hesitant towards less intensive surveillance. Perceived advantages of less intensive surveillance were: less distressing moments, leaving the patient role behind, and lower burden. Disadvantages were: fewer moments for reassurance, fear of missing recurrences, and a higher threshold for aftercare for side effects. CONCLUSIONS: SDM about post-treatment surveillance is desirable. Although women are hesitant about less intensive surveillance, they are open to the use of personalised risk assessment for recurrences in decision-making about surveillance. IMPLICATIONS FOR CANCER SURVIVORS: To facilitate SDM about post-treatment surveillance, the timing and content of information provision should be improved. Risk information should be provided in an accessible and understandable way. Moreover, fear of cancer recurrence and other personal considerations should be addressed in the process of SDM.

Changes in breast cancer treatment during the COVID-19 pandemic: a Dutch population-based study.

PURPOSE: We aimed to compare (1) treatments and time intervals between treatments of breast cancer patients diagnosed during and before the COVID-19 pandemic, and (2) the number of treatments started during and before the pandemic. METHODS: Women were selected from the Netherlands Cancer Registry. For aim one, odds ratios (OR) and 95% confidence intervals (95%CI) were calculated to compare the treatment of women diagnosed within four periods of 2020: pre-COVID (weeks 1-8), transition (weeks 9-12), lockdown (weeks 13-17), and care restart (weeks 18-26), with data from 2018/2019 as reference. Wilcoxon rank-sums test was used to compare treatment intervals, using a two-sided p-value < 0.05. For aim two, number of treatments started per week in 2020 was compared with 2018/2019. RESULTS: We selected 34,097 women for aim one. Compared to 2018/2019, neo-adjuvant chemotherapy was less likely for stage I (OR 0.24, 95%CI 0.11-0.53), stage II (OR 0.63, 95%CI 0.47-0.86), and hormone receptor+/HER2- tumors (OR 0.55, 95%CI 0.41-0.75) diagnosed during transition. Time between diagnosis and first treatment decreased for patients diagnosed during lockdown with a stage I (p < 0.01), II (p < 0.01) or III tumor (p = 0.01). We selected 30,002 women for aim two. The number of neo-adjuvant endocrine therapies and surgeries starting in week 14, 2020, increased by 339% and 18%, respectively. The number of adjuvant chemotherapies decreased by 42% in week 15 and increased by 44% in week 22. CONCLUSION: The pandemic and subsequently altered treatment recommendations affected multiple aspects of the breast cancer treatment strategy and the number of treatments started per week.

Supporting Shared Decision-making About Surveillance After Breast Cancer With Personalized Recurrence Risk Calculations: Development of a Patient Decision Aid Using the International Patient Decision AIDS Standards Development Process in Combination With a Mixed Methods Design.

BACKGROUND: Although the treatment for breast cancer is highly personalized, posttreatment surveillance remains one-size-fits-all: annual imaging and physical examination for at least five years after treatment. The INFLUENCE nomogram is a prognostic model for estimating the 5-year risk for locoregional recurrences and second primary tumors after breast cancer. The use of personalized outcome data (such as risks for recurrences) can enrich the process of shared decision-making (SDM) for personalized surveillance after breast cancer. OBJECTIVE: This study aimed to develop a patient decision aid (PtDA), integrating personalized risk calculations on risks for recurrences, to support SDM for personalized surveillance after curative treatment for invasive breast cancer. METHODS: For the development of the PtDA, the International Patient Decision Aids Standards development process was combined with a mixed methods design inspired by the development process of previously developed PtDAs. In the development, 8 steps were distinguished: establishing a multidisciplinary steering group; definition of the end users, scope, and purpose of the PtDA; assessment of the decisional needs of end users; defining requirements for the PtDA; determining the format and implementation strategy for the PtDA; prototyping; alpha testing; and beta testing. The composed steering group convened during regular working-group sessions throughout the development process. RESULTS: The "Breast Cancer Surveillance Decision Aid" consists of 3 components that support the SDM process: a handout sheet on which personalized risks for recurrences, calculated using the INFLUENCE-nomogram, can be visualized and which contains an explanation about the decision for surveillance and a login code for a web-based deliberation tool; a web-based deliberation tool, including a patient-reported outcome measure on fear of cancer recurrence; and a summary sheet summarizing patient preferences and considerations. The PtDA was assessed as usable and acceptable during alpha testing. Beta testing is currently ongoing. CONCLUSIONS: We developed an acceptable and usable PtDA that integrates personalized risk calculations for the risk for recurrences to support SDM for surveillance after breast cancer. The implementation and effects of the use of the "Breast Cancer Surveillance Decision Aid" are being investigated in a clinical trial.

De-escalation of radiotherapy after primary chemotherapy in cT1-2N1 breast cancer (RAPCHEM; BOOG 2010-03): 5-year follow-up results of a Dutch, prospective, registry study.

BACKGROUND: Primary chemotherapy in breast cancer poses a dilemma with regard to adjuvant locoregional radiotherapy, as guidelines for locoregional radiotherapy were originally based on pathology results of primary surgery. We aimed to evaluate the oncological safety of de-escalated locoregional radiotherapy in patients with cT1-2N1 breast cancer treated with primary chemotherapy, according to a predefined, consensus-based study guideline. METHODS: In this prospective registry study (RAPCHEM, BOOG 2010-03), patients referred to one of 17 participating radiation oncology centres in the Netherlands between Jan 1, 2011, and Jan 1, 2015, with cT1-2N1 breast cancer (one to three suspicious nodes on imaging before primary chemotherapy, of which at least one had been pathologically confirmed), and who were treated with primary chemotherapy and surgery of the breast and axilla were included in the study. The study guideline comprised three risk groups for locoregional recurrence, with corresponding locoregional radiotherapy recommendations: no chest wall radiotherapy and no regional radiotherapy in the low-risk group, only local radiotherapy in the intermediate-risk group, and locoregional radiotherapy in the high-risk group. Radiotherapy consisted of a biologically equivalent dose of 25 fractions of 2 Gy, with or without a boost. During the study period, the generally applied radiotherapy technique in the Netherlands was forward-planned or inverse-planned intensity modulated radiotherapy. 5-year follow-up was assessed, taking into account adherence to the study guideline, with locoregional recurrence rate as primary endpoint. We hypothesised that 5-year locoregional recurrence rate would be less than 4% (upper-limit 95% CI 7·8%). This study was registered at ClinicalTrials.gov, NCT01279304, and is completed. FINDINGS: 838 patients were eligible for 5-year follow-up analyses: 291 in the low-risk group, 370 in the intermediate-risk group, and 177 in the high-risk group. The 5-year locoregional recurrence rate in all patients was 2·2% (95% CI 1·4-3·4). The 5-year locoregional recurrence rate was 2·1% (0·9-4·3) in the low-risk group, 2·2% (1·0-4·1) in the intermediate-risk group, and 2·3% (0·8-5·5) in the high-risk group. If the study guideline was followed, the locoregional recurrence rate was 2·3% (0·8-5·3) for the low-risk group, 1·0% (0·2-3·4) for the intermediate-risk group, and 1·4% (0·3-4·5) for the high-risk group. INTERPRETATION: In this study, the 5-year locoregional recurrence rate was less than 4%, which supports our hypothesis that it is oncologically safe to de-escalate locoregional radiotherapy based on locoregional recurrence risk, in selected patients with cT1-2N1 breast cancer treated with primary chemotherapy, according to this predefined, consensus-based study guideline. FUNDING: Dutch Cancer Society. TRANSLATION: For the Dutch translation of the abstract see Supplementary Materials section.

Effectiveness and implementation of SHared decision-making supported by OUTcome information among patients with breast cancer, stroke and advanced kidney disease: SHOUT study protocol of multiple interrupted time series.

INTRODUCTION: Within the value-based healthcare framework, outcome data can be used to inform patients about (treatment) options, and empower them to make shared decisions with their health care professional. To facilitate shared decision-making (SDM) supported by outcome data, a multicomponent intervention has been designed, including patient decision aids on the organisation of post-treatment surveillance (breast cancer); discharge location (stroke) and treatment modality (advanced kidney disease), and training on SDM for health care professionals. The SHared decision-making supported by OUTcome information (SHOUT) study will examine the effectiveness of the intervention and its implementation in clinical practice. METHODS AND ANALYSIS: Multiple interrupted time series will be used to stepwise implement the intervention. Patients diagnosed with either breast cancer (N=630), stroke (N=630) or advanced kidney disease (N=473) will be included. Measurements will be performed at baseline, three (stroke), six and twelve (breast cancer and advanced kidney disease) months. Trends on outcomes will be measured over a period of 20 months. The primary outcome will be patients' perceived level of involvement in decision-making. Secondary outcomes regarding effectiveness will include patient-reported SDM, decisional conflict, role in decision-making, knowledge, quality of life, preferred and chosen care, satisfaction with the intervention, healthcare utilisation and health outcomes. Outcomes regarding implementation will include the implementation rate and a questionnaire on the health care professionals' perspective on the implementation process. ETHICS AND DISSEMINATION: The Medical research Ethics Committees United in Nieuwegein, the Netherlands, has confirmed that the Medical Research Involving Human Subjects Act does not apply to this study. Bureau Onderzoek & Innovatie of Santeon, the Netherlands, approved this study. The results will contribute to insight in and knowledge on the use of outcome data for SDM, and can stimulate sustainable implementation of SDM. TRIAL REGISTRATION NUMBER: NL8374, NL8375 and NL8376.

Failure of stereotactic core needle biopsy in women recalled for suspicious calcifications at screening mammography: frequency, causes, and final outcome in a multi-institutional, observational follow-up study.

OBJECTIVES: We determined the failure rate of stereotactic core needle biopsy (SCNB) and its causes and final outcome in women recalled for calcifications at screening mammography. METHODS: We included a consecutive series of 624,039 screens obtained in a Dutch screening region between January 2009 and July 2019. Radiology reports and pathology results were obtained of all recalled women during 2-year follow-up. RESULTS: A total of 3495 women (19.6% of 17,809 recalls) were recalled for suspicious calcifications. SCNB was indicated in 2818 women, of whom 12 had incomplete follow-up and another 12 women refused biopsy. DCIS or invasive cancer was diagnosed in 880 of the remaining 2794 women (31.5%). SCNB failed in 62 women (2.2%, 36/2794). These failures were mainly due to a too posterior (n = 30) or too superficial location (n = 17) of the calcifications or calcifications too faint for biopsy (n = 13). Of these 62 women, 10 underwent surgical biopsy, yielding one DCIS (intermediate grade) and two invasive cancers (one intermediate grade and one high grade) and another two women were diagnosed with DCIS (both high grade) at follow-up. Thus, the malignancy rate after SCNB failure was 8.1% (5/62). Calcifications were depicted neither at SCNB specimen radiography nor at pathology in 16 women after (repeated) SCNB (0.6%, 31/2732). None of them proved to have breast cancer at 2-year follow-up. CONCLUSIONS: The failure rate of SCNB for suspicious calcifications is low but close surveillance is warranted, as breast cancer may be present in up to 8% of these women. KEY POINTS: • The failure rate of stereotactic core needle biopsy (SCNB) for calcifications recalled at screening mammography was 2.2%. • Failures were mainly due to calcifications that could not be reached by SCNB or calcifications too faint for biopsy. • The management after failed SCNB was various. At least, close surveillance with a low threshold for surgical biopsy is recommended as breast cancer may be present in up to 8% of women with SCNB failure.

Using guideline-based clinical decision support in oncological multidisciplinary team meetings: A prospective, multicenter concordance study.

BACKGROUND: Multidisciplinary team meetings formulate guideline-based individual treatment plans based on patient and disease characteristics and motivate reasons for deviation. Clinical decision trees could support multidisciplinary teams to adhere more accurately to guidelines. Every clinical decision tree is tailored to a specific decision moment in a care pathway and is composed of patient and disease characteristics leading to a guideline recommendation. OBJECTIVE: This study investigated (1) the concordance between multidisciplinary team and clinical decision tree recommendations and (2) the completeness of patient and disease characteristics available during multidisciplinary team meetings to apply clinical decision trees such that it results in a guideline recommendation. METHODS: This prospective, multicenter, observational concordance study evaluated 17 selected clinical decision trees, based on the prevailing Dutch guidelines for breast, colorectal and prostate cancers. In cases with sufficient data, concordance between multidisciplinary team and clinical decision tree recommendations was classified as concordant, conditional concordant (multidisciplinary team specified a prerequisite for the recommendation) and non-concordant. RESULTS: Fifty-nine multidisciplinary team meetings were attended in 8 different hospitals, and 355 cases were included. For 296 cases (83.4%), all patient data were available for providing an unconditional clinical decision tree recommendation. In 59 cases (16.6%), insufficient data were available resulting in provisional clinical decision tree recommendations. From the 296 successfully generated clinical decision tree recommendations, the multidisciplinary team recommendations were concordant in 249 (84.1%) cases, conditional concordant in 24 (8.1%) cases and non-concordant in 23 (7.8%) cases of which in 7 (2.4%) cases the reason for deviation from the clinical decision tree generated guideline recommendation was not motivated. CONCLUSION: The observed concordance of recommendations between multidisciplinary teams and clinical decision trees and data completeness during multidisciplinary team meetings in this study indicate a potential role for implementation of clinical decision trees to support multidisciplinary team decision-making.

Quilting following mastectomy reduces seroma, associated complications and health care consumption without impairing patient comfort.

BACKGROUND: An important complication following mastectomy is seroma formation. Quilting, in which skin flaps are sutured to the underlying muscle, is reported to reduce seroma incidence, but might induce pain and impair shoulder function. Main objective is to compare quilting with conventional wound closure, regarding seroma incidence, health care consumption, and patient discomfort. METHODS: In a combined prospective and retrospective study, 254 patients undergoing mastectomy and/or axillary lymph node dissection (ALND) were included. Patients received quilting sutures or conventional closure. Primary outcome was clinical significant seroma (CSS). In prospectively included patients shoulder function and analgesic use was observed. RESULTS: CSS incidence was 12.9% in the quilted versus 62.3% in the nonquilted cohort (p < 0.001). Surgical site infections were reported significantly less in the quilted cohort. Duration of hospital stay was shorter and outpatient clinic visits were less in the quilted cohort. Surgical procedure required 10 additional minutes for quilting. No significant differences were observed in postoperative shoulder function and analgesic use. CONCLUSION: Quilting following mastectomy reduces CSS incidence. Quilting requires 10 additional minutes during surgery. It facilitates day treatment and results in less additional outpatient clinic visits culminating in reduced health care consumption. Shoulder function and pain are not affected by quilting.

Improved risk estimation of locoregional recurrence, secondary contralateral tumors and distant metastases in early breast cancer: the INFLUENCE 2.0 model.

PURPOSE: To extend the functionality of the existing INFLUENCE nomogram for locoregional recurrence (LRR) of breast cancer toward the prediction of secondary primary tumors (SP) and distant metastases (DM) using updated follow-up data and the best suitable statistical approaches. METHODS: Data on women diagnosed with non-metastatic invasive breast cancer were derived from the Netherlands Cancer Registry (n = 13,494). To provide flexible time-dependent individual risk predictions for LRR, SP, and DM, three statistical approaches were assessed; a Cox proportional hazard approach (COX), a parametric spline approach (PAR), and a random survival forest (RSF). These approaches were evaluated on their discrimination using the Area Under the Curve (AUC) statistic and on calibration using the Integrated Calibration Index (ICI). To correct for optimism, the performance measures were assessed by drawing 200 bootstrap samples. RESULTS: Age, tumor grade, pT, pN, multifocality, type of surgery, hormonal receptor status, HER2-status, and adjuvant therapy were included as predictors. While all three approaches showed adequate calibration, the RSF approach offers the best optimism-corrected 5-year AUC for LRR (0.75, 95%CI: 0.74-0.76) and SP (0.67, 95%CI: 0.65-0.68). For the prediction of DM, all three approaches showed equivalent discrimination (5-year AUC: 0.77-0.78), while COX seems to have an advantage concerning calibration (ICI < 0.01). Finally, an online calculator of INFLUENCE 2.0 was created. CONCLUSIONS: INFLUENCE 2.0 is a flexible model to predict time-dependent individual risks of LRR, SP and DM at a 5-year scale; it can support clinical decision-making regarding personalized follow-up strategies for curatively treated non-metastatic breast cancer patients.

Follow-up after breast cancer: Variations, best practices, and opportunities for improvement according to health care professionals.

OBJECTIVE: Follow-up after breast cancer can be divided into surveillance and aftercare. It remains unclear how follow-up can ideally be organised from the perspective of health care professionals (HCPs). The aim of this study was to gain insight in the organisation of follow-up in seven Dutch teaching hospitals and to identify best practices and opportunities for improvement of breast cancer (all stages) follow-up as proposed by HCPs. METHODS: Semi-structured in-depth group interviews were performed, one in each of the participating hospitals, with in total 16 HCPs and 2 patient advocates. To describe the organisation of follow-up, transcripts were analysed using a deductive approach. Best practices and opportunities were derived using an inductive approach. RESULTS: Variation was found in the organisation of aftercare, especially in timing, frequency, and disciplines of involved HCPs. Less variation was observed for surveillance, which was guided by the national guideline. Best practices focused on case management and adequate collaboration between HCPs of different disciplines. Mentioned opportunities were improving the structured monitoring of patients' needs and a comprehensive guideline for organisation and content of aftercare. CONCLUSIONS: Variation in follow-up existed between hospitals. Shared decision-making (SDM) about surveillance is desirable to ensure that surveillance matches the patient needs, preferences, and personal risk for recurrences.

Impact of the COVID-19 pandemic on diagnosis, stage, and initial treatment of breast cancer in the Netherlands: a population-based study.

BACKGROUND: The onset of the COVID-19 pandemic forced the Dutch national screening program to a halt and increased the burden on health care services, necessitating the introduction of specific breast cancer treatment recommendations from week 12 of 2020. We aimed to investigate the impact of COVID-19 on the diagnosis, stage and initial treatment of breast cancer. METHODS: Women included in the Netherlands Cancer Registry and diagnosed during four periods in weeks 2-17 of 2020 were compared with reference data from 2018/2019 (averaged). Weekly incidence was calculated by age group and tumor stage. The number of women receiving initial treatment within 3 months of diagnosis was calculated by period, initial treatment, age, and stage. Initial treatment, stratified by tumor behavior (ductal carcinoma in situ [DCIS] or invasive), was analyzed by logistic regression and adjusted for age, socioeconomic status, stage, subtype, and region. Factors influencing time to treatment were analyzed by Cox regression. RESULTS: Incidence declined across all age groups and tumor stages (except stage IV) from 2018/2019 to 2020, particularly for DCIS and stage I disease (p < 0.05). DCIS was less likely to be treated within 3 months (odds ratio [OR]wks2-8: 2.04, ORwks9-11: 2.18). Invasive tumors were less likely to be treated initially by mastectomy with immediate reconstruction (ORwks12-13: 0.52) or by breast conserving surgery (ORwks14-17: 0.75). Chemotherapy was less likely for tumors diagnosed in the beginning of the study period (ORwks9-11: 0.59, ORwks12-13: 0.66), but more likely for those diagnosed at the end (ORwks14-17: 1.31). Primary hormonal treatment was more common (ORwks2-8: 1.23, ORwks9-11: 1.92, ORwks12-13: 3.01). Only women diagnosed in weeks 2-8 of 2020 experienced treatment delays. CONCLUSION: The incidence of breast cancer fell in early 2020, and treatment approaches adapted rapidly. Clarification is needed on how this has affected stage migration and outcomes.

The Impact of Preoperative Breast MRI on Surgical Margin Status in Breast Cancer Patients Recalled at Biennial Screening Mammography: An Observational Cohort Study.

BACKGROUND: This study aimed to examine the association between preoperative magnetic resonance imaging (MRI) and surgical margin involvement, as well as to determine the factors associated with positive resection margins in screen-detected breast cancer patients undergoing breast-conserving surgery (BCS). METHODS: Breast cancer patients eligible for BCS and diagnosed after biennial screening mammography in the south of The Netherlands (2008-2017) were retrospectively included. Missing values were imputed and multivariable regression analyses were performed to analyze whether preoperative MRI was related to margin involvement after BCS, as well as to examine what factors were associated with positive resection margins, defined as more than focally (>4 mm) involved. RESULTS: Overall, 2483 patients with invasive breast cancer were enrolled, of whom 123 (5.0%) had more than focally involved resection margins. In multivariable regression analyses, preoperative MRI was associated with a reduced risk of positive resection margins after BCS (adjusted odds ratio [OR] 0.56, 95% confidence interval [CI] 0.33-0.96). Lobular histology (adjusted OR 2.86, 95% CI 1.68-4.87), large tumor size (per millimeter increase, adjusted OR 1.05, 95% CI 1.03-1.07), high (>75%) mammographic density (adjusted OR 3.61, 95% CI 1.07-12.12), and the presence of microcalcifications (adjusted OR 4.45, 95% CI 2.69-7.37) and architectural distortions (adjusted OR 1.85, 95% CI 1.01-3.40) were independently associated with positive resection margins after BCS. CONCLUSIONS: Preoperative MRI was associated with lower risk of positive resection margins in patients with invasive breast cancer eligible for BCS using multivariable analysis. Furthermore, specific mammographic characteristics and tumor characteristics were independently associated with positive resection margins after BCS.