Dataset Information

Effectiveness of radiotherapy after breast-conserving surgery in older patients with T1-2N0 breast cancer.

ABSTRACT:

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 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.

SUBMITTER: de Boer AZ

PROVIDER: S-EPMC6817758 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Publications

Effectiveness of radiotherapy after breast-conserving surgery in older patients with T1-2N0 breast cancer.

de Boer Anna Z AZ Bastiaannet Esther E de Glas Nienke A NA Marang-van de Mheen Perla J PJ Dekkers Olaf M OM Siesling Sabine S de Munck Linda L de Ligt Kelly M KM Portielje Johanneke E A JEA Liefers Gerrit Jan GJ

Breast cancer research and treatment 20190826 3

<h4>Purpose</h4>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.<h ...[more]

PMID: 31451977

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Dataset Information

Effectiveness of radiotherapy after breast-conserving surgery in older patients with T1-2N0 breast cancer.

Purpose

Methods

Results

Conclusions

Publications

Effectiveness of radiotherapy after breast-conserving surgery in older patients with T1-2N0 breast cancer.

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