G. Ulrich Exner

Bio: G. Ulrich Exner is an academic researcher. The author has contributed to research in topics: Survival rate & Mifamurtide. The author has an hindex of 1, co-authored 1 publications receiving 1549 citations.

Prognostic Factors in High-Grade Osteosarcoma of the Extremities or Trunk: An Analysis of 1,702 Patients Treated on Neoadjuvant Cooperative Osteosarcoma Study Group Protocols

Abstract: PURPOSE: To define prognostic factors for response and long-term outcome for a wide spectrum of osteosarcomas, extending well beyond those of the typical young patient with seemingly localized extremity disease. PATIENTS AND METHODS: A total of 1,702 consecutive newly diagnosed patients with high-grade osteosarcoma of the trunk or limbs registered into the neoadjuvant studies of the Cooperative Osteosarcoma Study Group before July 1998 were entered into an analysis of demographic, tumor-related, and treatment-related variables, response, and survival. The intended therapeutic strategy included preoperative and postoperative chemotherapy with multiple agents as well as surgery of all operable lesions. RESULTS: Axial tumor site, male sex, and a long history of symptoms were associated with poor response to chemotherapy in univariate and multivariate analysis. Actuarial 10-year overall and event-free survival rates were 59.8% and 48.9%. Among the variables assessable at diagnosis, patient age (actuarial 10-y...

Osteosarcoma: Current Treatment and a Collaborative Pathway to Success

Abstract: Osteosarcoma is the bone tumor that most commonly affects children, adolescents, and young adults. Before 1970, treatment primarily included surgical resection. However, the introduction of chemotherapy led to a dramatic improvement in prognosis for patients with localized osteosarcoma; long-term survival rates of less than 20% improved to 65% to 70% after the advent of multiagent chemotherapy regimens. Controversy concerning the ideal combination of chemotherapy agents ensued throughout the last quarter of the 20th century because of conflicting and often nonrandomized data. However, large cooperative group studies and international collaboration have demonstrated that the most effective regimens include the combination of high-dose methotrexate, doxorubicin, and cisplatin (MAP). The introduction of biologic agents such as muramyl tripeptide and the use of additional cytotoxic chemotherapy such as ifosfamide have not definitively improved the survival of patients with osteosarcoma. Collaborative efforts to increase understanding of the biology of osteosarcoma and the use of preclinical models to test novel agents will be critical to identify the path toward improving outcomes for patients. Once promising agents are identified, an international infrastructure exists for clinical trials. Herein, biologic, preclinical, and clinical trial efforts will be described along with future international collaborative strategies to improve outcomes for patients who develop this challenging tumor.

Primary Metastatic Osteosarcoma: Presentation and Outcome of Patients Treated on Neoadjuvant Cooperative Osteosarcoma Study Group Protocols

Abstract: Purpose: To determine demographic data and define prognostic factors for long-term outcome in patients presenting with high-grade osteosarcoma of bone with clinically detectable metastases at initial presentation. Patients and Methods: Of 1,765 patients with newly diagnosed, previously untreated high-grade osteosarcomas of bone registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies before 1999, 202 patients (11.4%) had proven metastases at diagnosis and therefore were enrolled onto an analysis of demographic-, tumor-, and treatment-related variables, response, and survival. The intended therapeutic strategy included pre- and postoperative multiagent chemotherapy as well as aggressive surgery of all resectable lesions. Results: With a median follow-up of 1.9 years (5.5 years for survivors), 60 patients were alive, 37 of whom were in continuously complete surgical remission. Actuarial overall survival rates at 5 and 10 (same value for 15) years were 29% (SE = 3%) and 24% (SE = 4%), respe...

Biology and Therapeutic Advances for Pediatric Osteosarcoma

Abstract: Osteosarcoma is the most common malignant bone tumor in children and adolescents. Survival for these patients was poor with the use of surgery and/or radiotherapy. The introduction of multi-agent chemotherapy dramatically improved the outcome for these patients and the majority of modern series report 3-year disease-free survival of 60%-70%. This paper describes current strategies for treating patients with osteosarcoma as well as review of the clinical features, radiologic and diagnostic work-up, and pathology. The authors review the state of the art management for patients with osteosarcoma in North America and Europe including the use of limb-salvage procedures and reconstruction as well as discuss the etiologic and biologic factors associated with tumor development. Therapy-related sequelae and future directions in the biology and therapy for these patients are also discussed.