The value of a risk prediction tool (PERSARC) for effectvie treatment decision making: a stepped wedge Randomized Controlled Trial.

Currently, there is no consensus about the optimal treatment for patients with
high grade soft tissue sarcomas (STS) which are localized in the extremities.
To ensure overall survival, there is a tendency to operate with wide resection
margins, but this has a high impact on quality of life especially when limb
function must be sacrificed. (Neo)adjuvant radiotherapy allows for narrower
surgical margins but is associated with significant short -and long-term
side-effects. As evidence on the best treatment is lacking, treatment choice
for individual patients should be driven by their weighing of the benefits and
harms of the treatment options in light of their personal situation.

However, current treatment decision-making in STS care is one-size fits all,
and not informed by individualized risks of treatment options and patients*
preferences. Consequently, there is no guarantee that patients with STS will
receive treatment that is appropriate for their situation, and patients
experience uncertainty about which treatment is best for their personal
situation (decisional conflict).

From literature it is known that decision supporting interventions contribute
to a better informed choice and less decisional conflict. Therefore, our
research group developed a validated personalized risk assessment tool
(Personalised Sarcoma Care: PERSARC) which provides patients and STS
professionals insight into the personalized risks and benefits of each
treatment option based on patient*s age, tumor size, tumor depth and histology
in their decision-making process.

It is hypothesized that use of PERSARC leads to significantly less decisional
conflict in patients and more informed decisions compared to usual care
(treatment decisions without use of PERSARC) by reducing the uncertainty
regarding risks and benefits of treatment options in high-grade extremity STS
patients.

To assess whether the use of the personalized risk assessment tool (PERSARC) is
(cost)effective in reducing decisional conflict and increasing informed choices
in high-grade extremity STS compared to usual care (co-primary outcomes). In
addition, we aim to assess in a process evaluation (a) the extent and way in
which PERSARC is used by patients and professionals, (b) how satisfied they
were with the use of PERSARC, and (c) whether they experienced barriers and
facilitators to the use of PERSARC. These insights in the mechanisms and
processes responsible for the success of PERSARC on predefined outcomes will
guide future implementation efforts.

To assess the (cost)effectiveness of PERSARC in treatment decisions of
high-grade extremity STS-patients, a parallel cluster randomized trial will be
conducted in the 8 Dutch hospitals that are STS expertise centers. Hospitals
will be randomized between standard care (control condition) or care with the
use of PERSARC (intervention). Outcomes will be assessed within one week after
treatment decision has been made (T1), and after 3, 6 and 12 months after the
treatment decision has been made (T2, T3, T4) in at least 120 patients. See
main study parameters/endpoints for a description of the outcomes that will be
measured at these time points. Actual use of PERSARC, satisfaction with/added
value of PERSARC and barriers and facilitators using PERSARC by patients and
professionals will be measured in a process evaluation using questionnaires,
interviews, and audio-recording/observation of consultations and
multidisciplinary meetings.

High-grade extremity STS patients will either receive standard care (control
group) or care with the use of PERSARC; i.e. PERSARC will be used in
multidisciplinary tumour boards to guide treatment advice and in consultation
in which the oncological/orthopaedic surgeon informs the patient about his/her
diagnoses and discusses the benefits and harms of all relevant treatment
options (intervention group).

The risk of this study are comparable with the risk of standard care. However
for patients allocated to the intervention group, it can be difficult to hear
about ones prognosis and to be actively involved in his/her own treatment
decision. Both groups (intervention and control) are asked to fill out
questionnaires within one week after the treatment decision has been made, and
3, 6 and 12 months after treatment decision has been made. Each questionnaire
can be filled in online and will take approximately 30 minutes. In total study
participants spend 130 minutes on this study (including informed consent
consultation (+/- 10min).

Furthermore, 5-15 randomly selected patients will be asked for an interview
about their experiences of their decision-making process with their orthopaedic
surgeon/ oncologist. These interviews will take about 45 minutes.