Background: The validity of the PREDICT breast cancer prognostic model is unclear for young patients without adjuvant systemic treatment. This study aimed to validate PREDICT and assess its... Show moreBackground: The validity of the PREDICT breast cancer prognostic model is unclear for young patients without adjuvant systemic treatment. This study aimed to validate PREDICT and assess its clinical utility in young women with node-negative breast cancer who did not receive systemic treatment.Methods: We selected all women from the Netherlands Cancer Registry who were diagnosed with node-negative breast cancer under age 40 between 1989 and 2000, a period when adjuvant systemic treatment was not standard practice for women with node-negative disease. We evaluated the calibration and discrimination of PREDICT using the observed/expected (O/E) mortality ratio, and the area under the receiver operating characteristic curve (AUC), respectively. Additionally, we compared the potential clinical utility of PREDICT for selectively administering chemotherapy to the chemotherapy-to-all strategy using decision curve analysis at predefined thresholds.Results: A total of 2264 women with a median age at diagnosis of 36 years were included. Of them, 71.2% had estrogen receptor (ER)-positive tumors and 44.0% had grade 3 tumors. Median tumor size was 16 mm. PREDICT v2.2 underestimated 10-year all-cause mortality by 33% in all women (O/E ratio:1.33, 95%CI:1.22-1.43). Model discrimination was moderate overall (AUC10-year:0.65, 95%CI:0.62-0.68), and poor for women with ER-negative tumors (AUC10-year:0.56, 95%CI:0.51-0.62). Compared to the chemotherapy-to-all strategy, PREDICT only showed a slightly higher net benefit in women with ER-positive tumors, but not in women with ER-negative tumors. Conclusions: PREDICT yields unreliable predictions for young women with node-negative breast cancer. Further model updates are needed before PREDICT can be routinely used in this patient subset. Show less
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... Show moreBackground 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. Show less
Purpose In the Netherlands, radiotherapy after breast-conserving surgery (BCS) is omitted in up to 30% of patients aged >= 75 years. Although omission of radiotherapy is considered an option for... Show morePurpose In the Netherlands, radiotherapy after breast-conserving surgery (BCS) is omitted in up to 30% of patients aged >= 75 years. Although omission of radiotherapy is considered an option for older women treated with endocrine treatment, the majority of these patients do not receive systemic treatment following Dutch treatment guidelines. Therefore, the aim of this study was to evaluate the effect of omission of radiotherapy on locoregional recurrence risk in this patient population.Methods Patients aged >= 75 years undergone BCS for T1-2N0 breast cancer diagnosed between 2003 and 2009 were selected from the Netherlands Cancer Registry. To minimize confounding by indication, hospital variation was used to assess the impact of radiotherapy-use on locoregional recurrence risk using cox proportional hazards regression. Hazards ratios with 95% confidence interval (CI) were estimated.Results Overall, 2390 patients were included. Of the patients with hormone receptor-positive breast cancer, 39.3% received endocrine treatment. Five-year incidences of locoregional recurrence were 1.9%, 2.8%, and 3.0% in patients treated at hospitals with higher (average radiotherapy-use 96.0%), moderate (88.0%), and lower radiotherapy-use (72.2%) respectively, and nine-year incidences were 2.2%, 3.1%, and 3.2% respectively. Adjusted hazard ratios were 1.46 (95% CI 0.77-2.78) and 1.50 (95% CI 0.79-2.85) for patients treated at hospitals with moderate and lower radiotherapy-use, compared to patient treated at hospitals with higher radiotherapy-use.Conclusions Despite endocrine treatment in only 39.3%, locoregional recurrence risk was low, even in patients treated at hospitals with lower radiotherapy-use. This provides reasonable grounds to consider omission of radiotherapy in patients aged >= 75 years with T1-2N0 breast cancer. Show less
Glas, N. de; Bastiaannet, E.; Boer, A. de; Siesling, S.; Liefers, G.J.; Portielje, J. 2019
PurposeThe number of older patients with breast cancer is rapidly increasing. A previous study showed that between 1990 and 2005, the survival of older patients with breast cancer did not improve... Show morePurposeThe number of older patients with breast cancer is rapidly increasing. A previous study showed that between 1990 and 2005, the survival of older patients with breast cancer did not improve in contrast to younger patients. In recent years, scientific evidence in the older age group has increased and specific guidelines for older women with breast cancer have been developed. The aim of this study was to assess changes in survival outcomes of older patients with breast cancer.Patients and methodsAll patients with breast cancer between 2000 and 2017 were included from the Netherlands cancer registry. We assessed changes in treatments using logistic regression. We calculated changes in relative survival as proxy for breast cancer mortality, stratified by age and stage.ResultsWe included 239,992 patients. Relative survival improved for patients<65 for all stages. In patients aged 65-75 years, relative survival did not improve in stage I-II but did improve in stage III breast cancer (RER 0.98, 95% CI 0.96-1.00, p=0.046). Concurrently, prescription of systemic treatments increased. In patients>75, relative survival did not improve in patients with stage I/II or stage III disease, nor did treatment strategies change.ConclusionsThis study shows that relative survival of patients aged 65-75 years with advanced breast cancer has improved, and concurrently, prescription of systemic treatment increased. To improve survival of patients >75 as well, future studies should focus on individualizing treatments based on concomitant comorbidity, geriatric parameters and the risk of competing mortality and toxicity of treatments. Show less
Boer, A.Z. de; Hulst, H.C. van der; Glas, N.A. de; Marang-van de Mheen, P.J.; Siesling, S.; Munck, L. de; ... ; Lieferso, G.J. 2019
Background Studies have demonstrated worse breast cancer-specific mortality with older age, despite an increasing risk of dying from other causes due to comorbidity (competing mortality). However,... Show moreBackground Studies have demonstrated worse breast cancer-specific mortality with older age, despite an increasing risk of dying from other causes due to comorbidity (competing mortality). However, findings on the association between older age and recurrence risk are inconsistent. The aim of this study was to assess incidences of locoregional and distant recurrence by age, taking competing mortality into account. Materials and Methods Patients surgically treated for nonmetastasized breast cancer between 2003 and 2009 were selected from The Netherlands Cancer Registry. Cumulative incidences of recurrence were calculated considering death without distant recurrence as competing event. Fine and Gray analyses were performed to characterize the impact of age (70-74 [reference group], 75-79, and >= 80 years) on recurrence risk. Results A total of 18,419 patients were included. Nine-year cumulative incidences of locoregional recurrence were 2.5%, 3.1%, and 2.9% in patients aged 70-74, 75-79, and >= 80 years, and 9-year cumulative incidences of distant recurrence were 10.9%, 15.9%, and 12.7%, respectively. After adjustment for tumor and treatment characteristics, age was not associated with locoregional recurrence risk. For distant recurrence, patients aged 75-79 years remained at higher risk after adjustment for tumor and treatment characteristics (75-79 years subdistribution hazard ratio [sHR], 1.25; 95% confidence interval [CI], 1.11-1.41; >= 80 years sHR, 1.03; 95% CI, 0.91-1.17). Conclusion Patients aged 75-79 years had a higher risk of distant recurrence than patients aged 70-74 years, despite the higher competing mortality. Individualizing treatment by using prediction tools that include competing mortality could improve outcome for older patients with breast cancer. Implications for Practice In this population-based study of 18,419 surgically treated patients aged 70 years or older, patients aged 75-79 years were at higher risk of distant recurrence than were patients aged 70-74 years. This finding suggests that patients in this age category are undertreated. In contrast, it was also demonstrated that the risk of dying without a recurrence strongly increases with age, and patients with a high competing mortality risk are easily overtreated. To identify older patients who may benefit from more treatment, clinicians should therefore take competing mortality risk into account. Prediction tools could facilitate this and thereby improve treatment strategy. Show less
Maaren, M.C. van; Cessie, S. le; Strobbe, L.J.A.; Groothuis-Oudshoorn, C.G.M.; Poortmans, P.M.P.; Siesling, S. 2019
Purpose: Patients may transfer of hospital for clinical reasons but this may delay time to treatment. The purpose of this study is to provide insight in the extent of hospital transfer in breast... Show morePurpose: Patients may transfer of hospital for clinical reasons but this may delay time to treatment. The purpose of this study is to provide insight in the extent of hospital transfer in breast cancer care; which type of patients transfer and what is the impact on time to treatment.Methods: We included 41,413 breast cancer patients registered in the Netherlands Cancer Registry between 2014 and 2016. We investigated transfer of hospital between diagnosis and first treatment being surgery or neoadjuvant chemotherapy (NAC). Co-variate adjusted characteristics predictive for hospital transfer were determined. To adjust for possible treatment by indication bias we used propensity score matching (PSM). Time to treatment in patients with and without hospital transfer was compared.Results: Among 41,413 patients, 8.5% of all patients transferred to another hospital between diagnosis and first treatment; 4.9% before primary surgery and 24.8% before NAC. Especially young (aged <40 years) patients and those who underwent a mastectomy with immediate breast reconstruction (IBR) were more likely to transfer. The association of mastectomy with IBR with hospital transfer remained when using PSM. Hospital transfer after diagnosis significantly prolonged time to treatment; breast conserving surgery by 5 days, mastectomy by 7 days, mastectomy with IBR by 9 days and NAC by 1 day.Conclusions: While almost 5% of Dutch patients treated with primary surgery transfer hospital after diagnosis and up to 25% for patients treated with NAC, our findings suggest that especially those treated with primary surgery are at risk for additional treatment delay by hospital transfer. (C) 2018 Published by Elsevier Ltd. Show less
Engelhardt, E.G.; Broek, A.J. van den; Linn, S.C.; Wishart, G.C.; Rutgers, E.J.T.; Velde, A.O. van de; ... ; Schmidt, M.K. 2017
