DESCARTES: De-ESCAlation of RadioTherapy in Patients With Pathologic Complete rESponse to Neoadjuvant Systemic Therapy

Study Overview
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Brief Summary
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This study evaluates whether radiotherapy can safely be omitted in breast cancer patients with T1-2N0 tumors who achieve a pathologic complete response after neoadjuvant systemic therapy and breast-conserving surgery

Detailed Description
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The proportion of women diagnosed with breast cancer who are treated with neoadjuvant systemic therapy is increasing. Depending on the subtype, 10-75% of these patients will have a pathologic complete response. Currently breast conserving surgery with pathologic complete response is followed by radiotherapy. In this patient group risk of local recurrence is low, but radiotherapy may cause considerable morbidity. The aim of this study is to investigate whether omitting radiotherapy is safe for patients with a node-negative breast tumor <5cm treated with neoadjuvant systemic therapy and breast conserving surgery who achieve a pathologic complete response

Official Title
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DESCARTES: De-ESCAlation of RadioTherapy in Patients With Pathologic Complete rESponse to Neoadjuvant Systemic Therapy

Conditions
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Breast Cancer

Intervention / Treatment
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* Radiation: Omission of radiotherapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women, aged ≥ 18 years Invasive HR positive/Her2 negative, Her2+ (ER/PR +/-) or TN breast cancer Primary tumor (T) clinical stage cT1-2 Unifocal disease Clinical nodal stage 0; absence of lymph node metastases should be confirmed by ultrasound or FDG-PET/CT Neoadjuvant systemic treatment (NST) and breast-conserving surgery Sentinel node biopsy performed before or after NST Pathologic complete response in breast and lymph nodes, i.e. no residual tumor cells detected Written informed consent Exclusion Criteria: Primary tumor (T) clinical stage cT3-4 DCIS associated with invasive carcinoma or elsewhere in ipsilateral breast Pre- or post-NST diagnosis of nodal disease including isolated tumour cells Patients without axillary ultrasound or FDG-PET/CT pre-NST History of breast cancer ipsilateral breast Synchronous contralateral breast cancer or DCIS Synchronous M1 disease Carrier of gene mutation associated with increased risk of breast cancer, i.e. BRCA1, BRCA2, CHEK2, TP53 or PALB-2

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Omission of radiotherapy<br> | Radiation: Omission of radiotherapy<br>* Omission of radiotherapy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Local recurrence | To show that radiotherapy after neoadjuvant systemic therapy and breast-conserving surgery can be omitted in T1-2N0 breast cancer patients who achieve pathologic complete response without compromising the 5 - year local recurrence rate (i.e, < 6% axillary recurrences within 5 years). | 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Level of cancer worry | The patients' experienced level of cancer worry will be measured using the validated 8-item Cancer Worry Scale (i.e., low (Cancer Worry Scale score ≤ 13 at each assessment) and high (Cancer Worry Scale score ≥14 at each assessment)). | 4 years | 
| Satisfaction reported by PROM (patient reported outcome measures) | The patients´experienced quality of life and satisfaction will be measured using the validated questionnaire EORTC-QLQ-C30 (Quality of life in cancer patients) and EORTC-QLQ-BR23 (Quality of life of patients with breast cancer) | 4 years | 
| Overall survival |  | 5 and 10 years | 
| Disease-specific survival |  | 5 and 10 years | 
| Locoregional recurrence |  | 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Breast cancer, Neoadjuvant Chemotherapy, Complete response, Radiotherapy