The Value of a Risk Prediction Tool (PERSARC) for Effective Treatment Decisions of Soft-tissue Sarcomas Patients

The goal of this clinical trial is to assess the (cost-)effectiveness of a personalised risk assessment tool (PERSARC) to increase patients' knowledge about risks and benefits of treatment options and to reduce decisional conflict in comparison with usual care in high-grade extremity Soft-Tissue Sarcoma-patients.

High-grade (2-3) extremity Soft-Tissue Sarcoma patients (\>= 18 years) 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)

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 Soft-Tissue Sarcoma patients compared to usual care (co-primary outcomes). In addition, we aim to assess in a process evaluation (a) the involvement of patients in decision-making (b) the extent and way PERSARC is used by patients and professionals, and (c) how satisfied patients and professionals were with the use of PERSARC.

Study design: To assess the (cost)effectiveness of PERSARC in treatment decisions of high-grade extremity Soft-Tissue Sarcoma-patients, a parallel cluster randomized trial will be conducted in the 6 Dutch hospitals that are Soft-tissue sarcoma 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 for the integration of PERSARC in treatment decision-making processes during patient-clinician encounters will be measured in a process evaluation using questionnaires, interviews, and audio-recording/observation of consultations.

Study population: Patients (\>= 18 years) with primarily diagnosed (histologically confirmed) grade 2-3 extremity Soft-Tissue Sarcoma, who do not have a treatment plan yet and will be treated with curative intent. Patients with sarcoma subtypes or treatment options other than those mentioned in PERSARC are unable to participate. Furthermore, patients need to be Dutch fluency and literacy and mentally competent.

Intervention (if applicable): High-grade extremity Soft-Tissue Sarcoma 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).

Main study parameters/endpoints: The co-primary outcomes are decisional conflict (Decisional Conflict Scale(DCS) (T1) and informed choice (T1). Informed choice is a combined outcome incorporating knowledge, attitudes concerning trade-offs between quality and length of life (QQ_Questionnaire) (T1), and treatment decision (T1). Secondary outcomes, include regret (Decision_Regret_Scale) (T3, T4), worry (Cancer_Worry_scale) (T1, T2, T3, T4), involvement in decision-making according to patients (SDM-Q-9) (T1), patient reported outcome using the Patient Reported Outcome Measures (PROMIS Global health) (T1, 2, 3, 4), and (PROMIS physical function) (T1, 2, 3, 4), utilities for the cost-effectiveness analysis (EQ-5D-5L) (T1, T2, T3, T4), health care cost (iMCQ) (T2, T3, T4) and absenteeism/presenteeism from paid work (T2, T3, T4).

Eligibility Criteria:
Inclusion Criteria:

* Patients \>= 18 years
* Histologically diagnosed with grade 2-3 STS in their extremities.
* Who do not have a treatment plan yet
* Dutch fluency and literacy
* Mentally competent
* Signed informed consent
* Patient owns a phone with internet access (WiFi)

Exclusion Criteria:

* Patient that are treated without curative intent
* Patient that needs to be treated with chemotherapy or isolated limb perfusion
* Patients were surgery is not indicated
* Sarcoma subtypes not included in the PERSARC risk assessment tool

In summary: patients with sarcoma subtypes and/or patients that need to be treated with other treatment modalities than those included in the PERSARC risk assessment tool are excluded.