Abstract
BACKGROUND: Breast cancer is the most common cancer type among women worldwide with over a million new cases each year. More than 40% of these women will struggle with chronic pain and fatigue after surgery, regardless of surgical procedure. These consequences are detrimental and result in distress and disability, including work disability. Few attempts have been made to prevent chronic pain and fatigue after surgery by applying a psychological approach, despite psychological risk factors being crucial in the development of both chronic pain and fatigue. In this study, we aim to develop and test an easily implementable strategy of preventing chronic pain and fatigue after breast cancer surgery. The intervention strategy involves a pre-operative hypnosis session and a web-based post-operative Acceptance and Commitment Therapy (ACT). The hypnosis has previously been found effective in alleviating acute post-operative pain and fatigue in breast cancer patients, while ACT is well suited to cancer populations as it offers a model of healthy adaptation to difficult circumstances. Together they form an intervention strategy with both a preventive and a rehabilitative focus. METHODS/DESIGN: This randomized controlled trial aims to estimate the effects of the pre- and post- operative interventions compared to attentional control and treatment as usual (TAU) and will also include a qualitative process evaluation. Participants will be randomized to receive either a pre-operative brief hypnosis session and a post-operative web-based psychological intervention (iACT) or a pre-operative one-session mindfulness through an audio file and post-operative TAU. Self-reported questionnaire data and biomarker data will be assessed pre-surgery, post-surgery and 3 and 12 months after surgery. In addition, we will assess registry data on sick leave and prescriptions until 2-year follow-up. In the qualitative process evaluation, data will be collected from participants from both study arms (through interviews and a diary) and two different analyses performed (socio-narrative and Grounded Theory) with the objective to describe the development of chronic post-surgical pain and fatigue and the potential influence of the interventions on these processes. The study is set-up to demonstrate a minimum difference in pain of 1 point on NRS (0-10) and 3 points on FACIT-F (0-52) between the groups at 3-months follow-up by including 200 breast cancer patients in total. DISCUSSION: This trial will be the first study to estimate the effect of a combined pre-operative hypnosis with a post-operative iACT to prevent pain and fatigue after breast cancer surgery. The results from our study might i) help the large group of women affected by chronic pain and fatigue after breast cancer surgery, ii) shed light on the mechanisms involved in chronic pain and fatigue development, and iii) serve as a model for other surgical procedures. TRIAL REGISTRATION: Clinicaltrials.gov, registration number NCT04518085. Registered on January 29th, 2020. https://clinicaltrials.gov/ct2/show/NCT04518085.