Short summary

The aim of this project is to elucidate whether the use of shared decision making will influence patient engagement in the decision process about adjuvant radiotherapy for patients operated with breast conservation for early node-negative breast cancer or ductal carcinoma in situ. A multicenter, national, randomized phase III trial is planned.

Rationale

This study takes place in cooperation with Danish Breast Cancer cooperative Group, DBCG. The name of this study is DBCG RT SDM.

Among patient organizations and politically in Denmark is an increasing call for more patient involvement in relevant health decision. Shared decision making is a clinical process in which clinicians and patients work together to make appropriate health decisions based on clinical evidence and the patient's informed preferences. A patient decision aid is a tool developed to support the process of shared decision making. The aim of shared decision making is to increase patient involvement in relevant health decisions.

The purpose of this study is to investigate whether shared decision making does increase patient involvement among Danish patients with breast cancer. This study will focus on the decision about whether to receive adjuvant radiotherapy after surgery for local breast cancer.

After surgery, most patients with breast cancer are recommended adjuvant treatment depending on their risk profile and patient characteristics. The risk of recurrence of breast cancer is lowered by adjuvant medical treatment as well as by radiotherapy. On the other hand, all the adjuvant treatments have risk of side effects; some of these side effects are acute and transient, while others may induce long term side effects. Considering the well-known side effects of irradiation, involving patients in the decision on whether to receive irradiation seems appropriate.

In this national, randomized study, half the patients will consult a doctor who practice shared decision making supported by a patient decision aid. The other half of the patients will consult a doctor who continues the usual approach to the consultation.

The primary endpoint will be patient engagement in the decision process about adjuvant radiotherapy, which will be evaluated using the validated 9-item SDM Questionnaire (SDM-Q-9). The secondary end points will measure the doctor's perception of patient engagement and the patient's fear of recurrence, decisional conflict, decision regret, patient engagement and quality of life. The decision on whether or not to receive adjuvant radiotherapy will also be registered. It is not expected that significantly fewer patients will receive adjuvant radiotherapy as a consequence of shared decision making.

A patient decision aid template earlier developed and clinically tested in accordance to the International Patient Decision Aids (IPDAS) criteria will form the basis for a customized patient decision aid for this specific decision on whether to receive adjuvant radiotherapy after breast conserving surgery.

The aim of this study is to create evidence on the effects of shared decision making in a Danish setting.

Description of the cohort

This study will include women over 18 years of age with histologically verified breast cancer, who are offered adjuvant radiotherapy DBCG type F after breast-conserving surgery for T1-2, N0-Nmi, M0 disease according to national guidelines. All participating patients must give written and oral confirmation of participation.

Data and biological material

The data will the patient's and doctor's answers to internationally recognized questionnaires.

Collaborating researchers and departments

Danish Breast Cancer cooperative Group, DBCG

Department of Oncology, Vejle Hospital

• Professor Karina Dahl Steffensen
• PhD Troels Bechmann

Department of Oncology, Aarhus University Hospital

• Professor Birgitte Offersen

Department of Oncology, Aalborg Hospital

• MD Lars Stenbygaard

Department of Oncology, Odense University Hospital

• MD Mette Holck Nielsen

Department of Oncology, Herlev University Hospital

• MD Susanne Vallentin Holm-Hansen

Department of Oncology, Naestved Hospital

• MD Kenneth Hofland