Amazone: Information for professionals

On this page you'll find important information for professionals working on the Amazone study.

Important links:

Microsoft Teams | Ldot | Castor EDC 

(Email for Microsoft Teams accces)

Status deelnemers | 21 november 2023

fpn amazone status deelnemers
Aantal nog te randomiseren deelneemsters per 21 november 2023.

A summary of the Amazone study protocol


Surviving breast cancer does not necessarily mean complete recovery to a premorbid state of health. In the past decade it became clear that cancer survivorship is a new diagnosis for patients with complex patterns of somatic and psychological distress requiring continuing complex medical care. Amongst these, persistent pain after breast cancer treatment (PPBCT) with a prevalence of 15-65% is probably the most invalidating, increasing survivor’s symptom burden and negatively affecting mood, sleep, daily activities, and quality of life. Once chronic, PPBCT is difficult to treat and requires a complex individualized multidisciplinary approach. Multiple individual and cancer treatment related risk factors for PPBCT have been identified in the past decades. Studies aiming to prevent PPBCT by modifying its somatic risk factors have not yet led to a significant reduction of PPBCT prevalence. Virtually NO studies have been performed to modify psychological distress before surgery with the aim of preventing persistent pain, even though for years studies about prevention persisting pain after surgery in general and PPBCT in particular have been suggesting the necessity for such an approach.


This study is designed to examine the preventive effect of pre- and postoperative psychological therapy on the development of PPBCT, specifically targeting patients with high levels of anxiety and/or pain catastrophizing. Treatment will be offered online, increasing accessibility and feasibility of participation in an emotionally and physically burdened time period.

Study design

The study is designed as a multi-center randomized controlled trial, with an additional control arm. Based on the answers in given in the baseline questionnaire, 138 Patients undergoing surgery for breast cancer will be randomized to one of two types of psychological intervention, and the remaining patients will undergo treatment as usual (Control). All patients are followed for 12 months.

Study population

Women undergoing unilateral surgery for breast cancer, aged above 18 years.


Five sessions of internet-based psychological therapy starting one to two weeks before surgery until six weeks after surgery.

Main study parameters/endpoints

Prevalence of significant PPBCT (NRS ≥3) at six months

Nature and extent of the burden and risks associated with participation, benefit and group relatedness

Patients scoring high for anxiety will be randomized to one of two types of psychological intervention: one consisting of reducing uncertainties by providing information about surgery and a healthy lifestyle and the other aiming at dealing with anxiety and negative cognitions. As the interventions are web-based, patients can use them wherever they are and also repeat sessions at their own discretion.

The non-randomized control group will receive treatment as usual (TAU) and will be asked to complete web-based questionnaires. In addition all randomized and non-randomized participants will be asked to participate in pre- and postoperative pain sensitivity testing (QST/CPM).

The burden consists of filling in online questionnaires (4 x 20 min), participating in QST/CPM assessments (2 x 90 minutes, 1 x 30 minutes) on a voluntary basis and for the intervention groups of the use e-CBT or web-based education in the perioperative period (5 x 60 minutes) and three short appointments with a therapist of 20-30 minutes each.

Benefit for patients in the psychological intervention group is a charge free psychological therapy potentially lowering the risk of persistent pain and other complications of breast cancer treatment.

If the treatment is effective, the developed web-based treatment can be offered to all breast cancer patients.

This project is unique in that it intervenes at a time point before persistent pain and other symptoms have established.

Because this is a single blind study, detailed information is available on request for professionals. Please mail to: