Cross-cultural Adaptation, Translation and Validation of the German Version of the Toronto Extremity Salvage Score (TESS) and Musculoskeletal Tumor Society (MSTS) for Patients With Bone and Soft Tissue Sarcoma in German Speaking

The most common primary bone tumors include osteosarcoma, Ewing's sarcoma and chondrosarcoma. The main symptom in patients with primary bone tumors is pain that can occur at rest or at night. The physical examination often shows swelling and restricted movement of the joints. Malignant bone tumors require multidisciplinary treatment that focuses on the surgical removal of the tumor. The extremity-preserving procedure contrasts with the amputation. Studies show that the functional result after restoration of the limb is superior to the amputation and that the relapse rate and mortality are comparable in both procedures. The goal of tumor resection is therefore to keep the treatment-related restrictions as low as possible, especially with regard to quality of life, function of the extremity and recurrence-free survival of the patients. The improvement of the functional results and longevity of reconstructive procedures remains a major challenge.

The same applies to the treatment of soft tissue sarcomas. However, early diagnosis is often hampered by atypical symptoms such as soft tissue swelling, painful lesions or no symptoms at all and is reported in the literature with an average period of time until the final diagnosis of 3 to 6 months. En bloc resection is the treatment of choice. Radiation therapy, chemotherapy and isolated hyperthermic limb perfusion can be used depending on tumor histology, degree and extent.

The measurement of the clinical outcome is of great importance. In order to objectify, measure and compare the success or failure of treatment with current literature and other tumor centers and to evaluate the invasive surgical procedures. Questionnaires such as the Toronto Extremity Salvage Score (TESS) and the Musculoskeletal Tumor Society (MSTS) were developed to measure the functional results after surgery and heterogeneity.

The TESS is a valid and disease-specific measure for evaluating functional disorders in patients between 12-85 years of age who are treated surgically for a bone or soft tissue sarcoma of the extremities. The questionnaire measures parameters such as Mobility, independence in everyday life, participation in social life and the pursuit of leisure activities. There is a version for the upper and one for the lower extremity with 30 questions each. Each question is rated on a 1-5 scale, with 5 being the value for normal performance. So far there have been studies to validate the TESS in Portuguese, Danish, Korean and Japanese.

The MSTS is an evaluation tool used worldwide to assess physical function in patients with musculoskeletal tumors. The questionnaire has already been successfully translated and validated in Portuguese and Japanese.