Susanne Oertel

Enhancement of Radiation Response in Osteosarcoma and Rhabomyosarcoma Cell Lines by Histone Deacetylase Inhibition

PURPOSE Histone deacetylase inhibitors (HDACIs) can enhance the sensitivity of cells to photon radiation treatment (XRT) by altering numerous molecular pathways. We investigated the effect of pan-HDACIs such as suberoylanilide hydroxamic acid (SAHA) on radiation response in two osteosarcoma (OS) and two rhabdomyosarcoma (RMS) cell lines. METHODS AND MATERIALS Clonogenic survival, cell cycle analysis, and apoptosis were examined in OS (KHOS-24OS, SAOS2) and RMS (A-204, RD) cell lines treated with HDACI and HDACI plus XRT, respectively. Protein expression was investigated via immunoblot analysis, and cell cycle analysis and measurement of apoptosis were performed using flow cytometry. RESULTS SAHA induced an inhibition of cell proliferation and clonogenic survival in OS and RMS cell lines and led to a significant radiosensitization of all tumor cell lines. Other HDACI such as M344 and valproate showed similar effects as investigated in one OS cell line. Furthermore, SAHA significantly increased radiation-induced apoptosis in the OS cell lines, whereas in the RMS cell lines radiation-induced apoptosis was insignificant with and without SAHA. In all investigated sarcoma cell lines, SAHA attenuated radiation-induced DNA repair protein expression (Rad51, Ku80). CONCLUSION Our results show that HDACIs enhance radiation action in OS and RMS cell lines. Inhibition of DNA repair, as well as increased apoptosis induction after exposure to HDACIs, can be mechanisms of radiosensitization by HDACIs.

Heidelberg Ion Therapy Center (HIT): Initial clinical experience in the first 80 patients.

Abstract The Heidelberg Ion Therapy Center (HIT) started clinical operation in November 2009. In this report we present the first 80 patients treated with proton and carbon ion radiotherapy and describe patient selection, treatment planning and daily treatment for different indications. Patients and methods. Between November 15, 2009 and April 15, 2010, 80 patients were treated at the Heidelberg Ion Therapy Center (HIT) with carbon ion and proton radiotherapy. Main treated indications consisted of skull base chordoma (n = 9) and chondrosarcoma (n = 18), malignant salivary gland tumors (n=29), chordomas of the sacrum (n = 5), low grade glioma (n=3), primary and recurrent malignant astrocytoma and glioblastoma (n=7) and well as osteosarcoma (n = 3). Of these patients, four pediatric patients aged under 18 years were treated. Results. All patients were treated using the intensity-modulated rasterscanning technique. Seventy six patients were treated with carbon ions (95%), and four patients were treated with protons. In all patients x-ray imaging was performed prior to each fraction. Treatment concepts were based on the initial experiences with carbon ion therapy at the Gesellschaft für Schwerionenforschung (GSI) including carbon-only treatments and carbon-boost treatments with photon-IMRT. The average time per fraction in the treatment room per patient was 29 minutes; for irradiation only, the mean time including all patients was 16 minutes. Position verification was performed prior to every treatment fraction with orthogonal x-ray imaging. Conclusion. Particle therapy could be included successfully into the clinical routine at the Department of Radiation Oncology in Heidelberg. Numerous clinical trials will subsequently be initiated to precisely define the role of proton and carbon ion radiotherapy in radiation oncology.

Human Glioblastoma and Carcinoma Xenograft Tumors Treated by Combined Radiation and Imatinib (Gleevec

Background and Purpose:Imatinib (Gleevec®, Glivec®) is an inhibitor of α- and β-platelet-derived growth factor receptors and other tyrosine kinases, that are also associated with the function of growth factors. Imatinib has been approved for the treatment of chronic myelogenous leukemia and gastrointestinal stromal tumors and is under investigation for the therapy of several other malignant tumors. Since radiotherapy is an important treatment option in many tumors, combined effects of imatinib and radiation were analyzed here.Material and Methods:In vitro, U87 cells (human glioblastoma), A431 cells (human epidermoid carcinoma), and HUVECs (human umbilical venous endothelial cells) were treated with imatinib alone and in combination with radiation. Clonogenic survival and cell proliferation were determined with and without additional radiation (0–10 Gy). In vivo, U87 and A431 cells (5 × 106) were subcutaneously injected into hind limbs of balb c nu/u mice. Drug and radiation treatments started on day 0 when tumor volumes were approximately 400–500 mm3. Tumors were treated with 5 × 5 Gy (U87) or 6 × 5 Gy (A431) on consecutive days from day 0. Imatinib was administered orally via the mouse diet starting on day 0 until the end of observation. Tumor growth and microvessel density (CD31 IHC) were analyzed.Results:In vitro, imatinib increased radiosensitivity of U87 and A431 tumor cells as well as HUVECs in both clonogenic and cell number/proliferation assays. The enhancement of radiosensitivity in HUVECs was comparable to that observed in the tumor cells. In vivo, the concurrent and continuous administration of imatinib increased tumor growth delay of fractionated radiotherapy in the carcinoma and the glioblastoma models at reduced microvessel densities. No apparent additional toxicity by the combination of radiation and imatinib versus monotherapies was observed in terms of weight, skin, or general behavior.Conclusion:Imatinib (Gleevec®), a “molecular targeted” approved drug for human malignancies, can enhance the tumor growth reduction induced by fractionated radiotherapy in glioblastoma and carcinoma models. The data provides a rationale to further investigate the combination.Hintergrund und Ziel:Die Dysregulation von Zellwachstum und Zelldifferenzierung, Hauptmerkmale der malignen Tumortransformation, entsteht durch eine chronisch-aberrante Aktivierung von Wachstumsfaktoren. Imatinib (Glivec®) inhibiert spezifische Tyrosinkinasen, wie PDGF-(„platelet-derived growth factor“) und c-KIT-Rezeptoren, welche Wachstumsrezeptoren darstellen oder mit deren Funktion assoziiert sind. Imatinib wird bei der Behandlung der chronischen myeloischen Leukämie und gastrointestinaler Stromatumoren bereits eingesetzt und bei einer Reihe weiterer Tumorentitäten in klinischen Studien untersucht. Strahlentherapie ist eine Option bei einigen dieser Tumoren, so dass die Untersuchung von Kombinationseffekten relevant ist.Material und Methodik:In vitro wurden U87-Zellen (humanes Glioblastom), A431-Zellen (humanes epidermoides Karzinom) und HUVECs (humane umbilikalvenöse Endothelzellen) bestrahlt und mit Imatinib behandelt. Klonogenes Überleben und Zellproliferation wurden bestimmt. In vivo wurden U87- und A431-Tumoren auf Balb-c-nu/u-Mäusen untersucht. Die Behandlung begann bei Tumorvolumina von 400–500 mm3 mit 5 × 5 Gy (U87) bzw. 6 × 5 Gy (A431). Imatinib wurde kontinuierlich ab Therapiebeginn gleichzeitig zur Strahlentherapie bis zum Beobachtungsende verabreicht. Die Tumorgröße und die Mikrogefäßdichte (CD31 IHC) wurden analysiert.Ergebnisse:Imatinib erhöhte die Strahlensensibilität von U87-Zellen und HUVECs, weniger ausgeprägt auch von A431-Zellen, im klonogenen und Proliferations-Assay. Der Effekt unterschied sich bei Endothelzellen nicht signifikant von jenem bei den Tumorzellen. In vivo vergrößerte die zusätzliche Gabe von Imatinib die Tumorwachstumsverzögerung durch Strahlentherapie beim Glioblastom und beim Karzinom bei deutlicher Reduktion der Mikrogefäßdichte ohne erkennbare Zunahme der Toxizität.Schlussfolgerung:Imatinib (Gleevec®) als klinisch zugelassener Vertreter der „Targeted therapy“-Medikamente kann den tumorwachstumshemmenden Effekt einer fraktionierten Strahlentherapie beim Glioblastom und bei Karzinomen verstärken, was weiter untersucht werden sollte.

Non-randomized therapy trial to determine the safety and efficacy of heavy ion radiotherapy in patients with non-resectable osteosarcoma

BackgroundOsteosarcoma is the most common primary malignant bone tumor in children and adolescents. For effective treatment, local control of the tumor is absolutely critical, because the chances of long term survival are <10% and might effectively approach zero if a complete surgical resection of the tumor is not possible. Up to date there is no curative treatment protocol for patients with non-resectable osteosarcomas, who are excluded from current osteosarcoma trials, e.g. EURAMOS1. Local photon radiotherapy has previously been used in small series and in an uncontrolled, highly individualized fashion, which, however, documented that high dose radiotherapy can, in principle, be used to achieve local control. Generally the radiation dose that is necessary for a curative approach can hardly be achieved with conventional photon radiotherapy in patients with non-resectable tumors that are usually located near radiosensitive critical organs such as the brain, the spine or the pelvis. In these cases particle Radiotherapy (proton therapy (PT)/heavy ion therapy (HIT) may offer a promising new alternative. Moreover, compared with photons, heavy ion beams provide a higher physical selectivity because of their finite depth coverage in tissue. They achieve a higher relative biological effectiveness. Phase I/II dose escalation studies of HIT in adults with non-resectable bone and soft tissue sarcomas have already shown favorable results.Methods/DesignThis is a monocenter, single-arm study for patients ≥ 6 years of age with non-resectable osteosarcoma. Desired target dose is 60-66 Cobalt Gray Equivalent (Gy E) with 45 Gy PT (proton therapy) and a carbon ion boost of 15-21 GyE. Weekly fractionation of 5-6 × 3 Gy E is used. PT/HIT will be administered exclusively at the Ion Radiotherapy Center in Heidelberg. Furthermore, FDG-PET imaging characteristics of non-resectable osteosarcoma before and after PT/HIT will be investigated prospectively. Systemic disease before and after PT/HIT is targeted by standard chemotherapy protocols and is not part of this trial.DiscussionThe primary objectives of this trial are the determination of feasibility and toxicity of HIT. Secondary objectives are tumor response, disease free survival and overall survival. The aim is to improve outcome for patients with non-resectable osteosarcoma.Trail RegistrationRegistration number (ClinicalTrials.gov): NCT01005043

Treatment of pediatric patients and young adults with particle therapy at the Heidelberg Ion Therapy Center (HIT): establishment of workflow and initial clinical data

BackgroundTo report on establishment of workflow and clinical results of particle therapy at the Heidelberg Ion Therapy Center.Materials and methodsWe treated 36 pediatric patients (aged 21 or younger) with particle therapy at HIT. Median age was 12 years (range 2-21 years), five patients (14%) were younger than 5 years of age. Indications included pilocytic astrocytoma, parameningeal and orbital rhabdomyosarcoma, skull base and cervical chordoma, osteosarcoma and adenoid-cystic carcinoma (ACC), as well as one patient with an angiofibroma of the nasopharynx. For the treatment of small children, an anesthesia unit at HIT was established in cooperation with the Department of Anesthesiology.ResultsTreatment concepts depended on tumor type, staging, age of the patient, as well as availability of specific study protocols. In all patients, particle radiotherapy was well tolerated and no interruptions due to toxicity had to be undertaken. During follow-up, only mild toxicites were observed. Only one patient died of tumor progression: Carbon ion radiotherapy was performed as an individual treatment approach in a child with a skull base recurrence of the previously irradiated rhabdomyosarcoma. Besides this patient, tumor recurrence was observed in two additional patients.ConclusionClinical protocols have been generated to evaluate the real potential of particle therapy, also with respect to carbon ions in distinct pediatric patient populations. The strong cooperation between the pediatric department and the department of radiation oncology enable an interdisciplinary treatment and stream-lined workflow and acceptance of the treatment for the patients and their parents.

Intraoperative Electron Radiotherapy for the Management of Aggressive Fibromatosis

PURPOSE We analyzed our experience with intraoperative electron radiotherapy (IOERT) followed by moderate doses of external beam radiotherapy (EBRT) after organ-sparing surgery in patients with primary or recurrent aggressive fibromatosis. METHODS AND MATERIALS Indication for IOERT and postoperative EBRT as an individual treatment approach to avoid mutilating surgical procedures was seen when complete surgical removal seemed to be unlikely or impossible. A total of 31 lesions in 30 patients were treated by surgery and IOERT with a median dose of 12 Gy. Median age was 31 years (range, 13-59 years). Resection status was close margin in six lesions, microscopically positive in 13, and macroscopically positive in 12. Median tumor size was 9 cm. In all, 25 patients received additional EBRT, with a median dose of 45 Gy (range, 36-54 Gy). RESULTS After a median follow-up of 32 months (range, 3-139 months), no disease-related deaths occurred. A total of five local recurrences were seen, resulting in actuarial 3-year local control rates of 82% overall and 91% inside the IOERT areas. Trends to improved local control were seen for older age (>31 years) and negative margins, but none of these factors reached significance. Perioperative complications were found in six patients, in particular as wound healing disturbances in five patients and venous thrombosis in one patient. Late toxicity was seen in five patients. CONCLUSION Introduction of IOERT into a multimodal treatment approach in patients with aggressive fibromatosis is feasible with low toxicity and yielded good local control rates even in patients with microscopical or gross residual disease.

Total body irradiation (TBI) in pediatric patients. A single-center experience after 30 years of low-dose rate irradiation.

AbstractPurpose:To retrospectively analyze patient characteristics, treatment, and treatment outcome of pediatric patients with hematologic diseases treated with total body irradiation (TBI) between 1978 and 2006.Patients and Methods:32 pediatric patients were referred to the Department of Radiation-Oncology at the University of Zurich for TBI. Records of regular follow-up of 28 patients were available for review. Patient characteristics as well as treatment outcome regarding local control and overall survival were assessed. A total of 18 patients suffered from acute lymphoblastic leukemia (ALL), 5 from acute and 2 from chronic myelogenous leukemia, 1 from non-Hodgkin lymphoma, and 2 from anaplastic anemia. The cohort consisted of 15 patients referred after first remission and 13 patients with relapsed leukemia. Mean follow-up was 34 months (2–196 months) with 15 patients alive at the time of last follow-up. Eight patients died of recurrent disease, 1 of graft vs. host reaction, 2 of sepsis, and 2 patients died of a secondary malignancy.Results:The 5-year overall survival rate (OS) was 60%. Overall survival was significantly inferior in patients treated after relapse compared to those treated for newly diagnosed leukemia (24% versus 74%; p=0.004). At the time of last follow-up, 11 patients survived for more than 36 months following TBI. Late effects (RTOG ≥3) were pneumonitis in 1 patient, chronic bronchitis in 1 patient, cardiomyopathy in 2 patients, severe cataractogenesis in 1 patient (48 months after TBI with 10 Gy in a single dose) and secondary malignancies in 2 patients (36 and 190 months after TBI). Growth disturbances were observed in all patients treated prepubertally. In 2 patients with identical twins treated at ages 2 and 7, a loss of 8% in final height of the treated twin was observed.Conclusion:As severe late sequelae after TBI, we observed 2 secondary malignancies in 11 patients who survived in excess of 36 months. However, long-term morbidity is moderate following treatment with the fractionated TBI at the low-dose rate that was generally used here. Conditioning for bone marrow transplantation without radiation is an attractive option, but is not sufficiently effective to completely replace TBI for the most common pediatric indications.ZusammenfassungZiel:Retrospektive Analyse von Patientencharakteristika, Behandlung und Ergebnis bei Kindern mit hämatologischen Erkrankungen, die zwischen 1978 und 2006 mit Ganzkörperbestrahlung behandelt wurden.Patienten und Methodik:32 Kinder wurden unserer Klinik zur TBI zugewiesen, 28 Krankengeschichten waren zugänglich (n=28). 18 Patienten litten unter akuter lymphoblastischer Leukämie (ALL), 5 unter akuter (AML) und 2 unter chronisch myeloischer Leukämie (CML), einer unter Non-Hodgkin-Lymphom und zwei unter aplastischer Anämie. 15 Patienten wurden nach erster Remission zugewiesen, 13 mit Rezidiv. Bei der letzten Kontrolle lebten noch 15 Patienten (mean 34 Monate (2–196 Monate). Acht Patienten sind an einem Rezidiv verstorben, einer an einer Graft-versus-host Erkrankung, zwei an Sepsis und zwei an Sekundärtumoren.Resultate:Das 5-Jahres Gesamtüberleben lag bei 60%. Das Gesamtüberleben war signifikant (p=0.004) niedriger bei Patienten, die nach einem Rezidiv behandelt wurden (24%), als bei solchen die bei Erstdiagnose behandelt wurden (74%). Spättoxizität RTOG ≥3 waren eine Pneumonitis bei 1 Patienten, eine chronische Bronchitis bei einem Patienten, Kardiomyopathie bei 2 Patienten, eine Katarakt bei einem Patienten (48 Monate nach TBI mit 10Gy Einzeldosis) und Sekundärtumore bei 2 Patienten. Wachstumsstörungen mit einer Körpergrösse kleiner als die 25. Perzentile zeigten sich bei allen vor der Pubertät behandelten Kindern. Bei zwei eineiigen Zwillingen zeigt sich ein Verlust von 8% an Körpergrösse im Vergleich zum Zwilling.Schlussfolgerung:Wie erwartet zeigen sich schwere Spättoxizitäten nach Ganzkörperbestrahlung mit zwei Sekundärtumoren bei 11 Patienten, die länger als 36 Monate überlebt haben. Aber die Morbidität ist mässig nach fraktionierter Ganzkörperbestrahlung und der hier in fast allen Fällen verwendeten niedrigen Dosisrate. Konditionierung ohne TBI ist eine attraktive Möglichkeit, aber noch nicht effektiv genug um die TBI im Kindesalter ganz zu ersetzen.

Total Body Irradiation (TBI) in Pediatric Patients

AbstractPurpose:To retrospectively analyze patient characteristics, treatment, and treatment outcome of pediatric patients with hematologic diseases treated with total body irradiation (TBI) between 1978 and 2006.Patients and Methods:32 pediatric patients were referred to the Department of Radiation-Oncology at the University of Zurich for TBI. Records of regular follow-up of 28 patients were available for review. Patient characteristics as well as treatment outcome regarding local control and overall survival were assessed. A total of 18 patients suffered from acute lymphoblastic leukemia (ALL), 5 from acute and 2 from chronic myelogenous leukemia, 1 from non-Hodgkin lymphoma, and 2 from anaplastic anemia. The cohort consisted of 15 patients referred after first remission and 13 patients with relapsed leukemia. Mean follow-up was 34 months (2–196 months) with 15 patients alive at the time of last follow-up. Eight patients died of recurrent disease, 1 of graft vs. host reaction, 2 of sepsis, and 2 patients died of a secondary malignancy.Results:The 5-year overall survival rate (OS) was 60%. Overall survival was significantly inferior in patients treated after relapse compared to those treated for newly diagnosed leukemia (24% versus 74%; p=0.004). At the time of last follow-up, 11 patients survived for more than 36 months following TBI. Late effects (RTOG ≥3) were pneumonitis in 1 patient, chronic bronchitis in 1 patient, cardiomyopathy in 2 patients, severe cataractogenesis in 1 patient (48 months after TBI with 10 Gy in a single dose) and secondary malignancies in 2 patients (36 and 190 months after TBI). Growth disturbances were observed in all patients treated prepubertally. In 2 patients with identical twins treated at ages 2 and 7, a loss of 8% in final height of the treated twin was observed.Conclusion:As severe late sequelae after TBI, we observed 2 secondary malignancies in 11 patients who survived in excess of 36 months. However, long-term morbidity is moderate following treatment with the fractionated TBI at the low-dose rate that was generally used here. Conditioning for bone marrow transplantation without radiation is an attractive option, but is not sufficiently effective to completely replace TBI for the most common pediatric indications.ZusammenfassungZiel:Retrospektive Analyse von Patientencharakteristika, Behandlung und Ergebnis bei Kindern mit hämatologischen Erkrankungen, die zwischen 1978 und 2006 mit Ganzkörperbestrahlung behandelt wurden.Patienten und Methodik:32 Kinder wurden unserer Klinik zur TBI zugewiesen, 28 Krankengeschichten waren zugänglich (n=28). 18 Patienten litten unter akuter lymphoblastischer Leukämie (ALL), 5 unter akuter (AML) und 2 unter chronisch myeloischer Leukämie (CML), einer unter Non-Hodgkin-Lymphom und zwei unter aplastischer Anämie. 15 Patienten wurden nach erster Remission zugewiesen, 13 mit Rezidiv. Bei der letzten Kontrolle lebten noch 15 Patienten (mean 34 Monate (2–196 Monate). Acht Patienten sind an einem Rezidiv verstorben, einer an einer Graft-versus-host Erkrankung, zwei an Sepsis und zwei an Sekundärtumoren.Resultate:Das 5-Jahres Gesamtüberleben lag bei 60%. Das Gesamtüberleben war signifikant (p=0.004) niedriger bei Patienten, die nach einem Rezidiv behandelt wurden (24%), als bei solchen die bei Erstdiagnose behandelt wurden (74%). Spättoxizität RTOG ≥3 waren eine Pneumonitis bei 1 Patienten, eine chronische Bronchitis bei einem Patienten, Kardiomyopathie bei 2 Patienten, eine Katarakt bei einem Patienten (48 Monate nach TBI mit 10Gy Einzeldosis) und Sekundärtumore bei 2 Patienten. Wachstumsstörungen mit einer Körpergrösse kleiner als die 25. Perzentile zeigten sich bei allen vor der Pubertät behandelten Kindern. Bei zwei eineiigen Zwillingen zeigt sich ein Verlust von 8% an Körpergrösse im Vergleich zum Zwilling.Schlussfolgerung:Wie erwartet zeigen sich schwere Spättoxizitäten nach Ganzkörperbestrahlung mit zwei Sekundärtumoren bei 11 Patienten, die länger als 36 Monate überlebt haben. Aber die Morbidität ist mässig nach fraktionierter Ganzkörperbestrahlung und der hier in fast allen Fällen verwendeten niedrigen Dosisrate. Konditionierung ohne TBI ist eine attraktive Möglichkeit, aber noch nicht effektiv genug um die TBI im Kindesalter ganz zu ersetzen.

Radiotherapy in the treatment of primary osteosarcoma - A single center experience

Purpose To analyze our experiences concerning radiation treatment in patients with osteosarcoma. Materials and methods Since 1981, 40 patients with osteosarcoma have undergone radiotherapy in Heidelberg; 3 of them were immediately lost to follow-up. Twenty patients with metastases were treated palliatively and 17 patients were treated with a curative intent. Results Interestingly, 14 of the 17 patients treated with a curative intent were referred to our clinic during the last 8 years, whereas the number of patients referred for palliation decreased. The mean dose applied for palliation was 47 Gy (range, 26 Gy to >70 GyE), for cure was 59 Gy (range, 45 Gy to >70 GyE). Local control until death could be achieved in 15 of the 20 palliatively treated patients, with a mean survival of 7 months after radiation. Five patients experienced local failure with symptom recurrence, and 3 of them had received doses >60 Gy. At last follow-up, 3 of the 17 curatively treated patients had experienced local recurrence. Median follow-up was 32 months (range, 3-144). Estimated 5-year overall survival and local control rates were 38% and 68%, respectively. Local disease-free survival was shorter in patients treated for recurrent, inoperable or incompletely resected tumors and doses below 60 Gy. Conclusions With adequate doses, long-term local control is possible even in inoperable or incompletely resected tumors. Improvements of systemic therapy and modern radiation techniques have begun to bring the possibly curative role of radiation treatment back to the fore. However, in disseminated tumors, even doses beyond 60 Gy do not guarantee local control, suggesting an extremely low radiosensitivity of certain kinds of osteosarcoma.

Prophylaxis of heterotopic ossification in patients sedated after polytrauma: medical and ethical considerations

Background and Purpose:Heterotopic ossification (HO) often follows acetabular fractures after multitrauma. Irradiation is a mean for prophylaxis. We established a standard procedure in our hospital for patients under sedation, when obtaining informed consent for HO prophylaxis is impossible.Patients and Methods:We reviewed current scientific evidence, calculated the risks of radiation and presented the ethical and legal framework. The subject was scrutinised by an interdisciplinary panel.Results:Irradiation is the most effective means for prophylaxis and has few adverse effects in adult patients with fractures of the acetabulum. The lifetime risk of radiation-induced cancer or infertility are insignificant.Conclusions:Informed consent for irradiation should be obtained before operation whenever possible. When this cannot be done prophylaxis can be postponed for a maximum of 3 days in order to obtain consent. If the patient is not able to communicate within this period, prophylactic irradiation should be given after consulting the relatives. The patient must be informed as soon as possible.Hintergrund und Ziel:Heterotope Ossifikationen (HO) entstehen häufig nach Acetabulumfrakturen. Übliche Methode der HOProphylaxe ist die Bestrahlung. Ziel unserer Arbeit war die Erarbeitung einer standardisierten Vorgehensweise bei sedierten Patienten.Patienten und Methodik:Der medizinische Kenntnisstand, rechtliche und ethische Aspekte wurden zusammengetragen und Berechnungen für strahleninduzierte Risiken durchgeführt. Auf dieser Basis wurde die Thematik von einer interdisziplinären Expertengruppe diskutiert.Ergebnisse:Die Bestrahlung bei Patienten mit Acetabulumfraktur ist effektiv und risikoarm. Das Lebenszeitrisiko zur Entwicklung eines strahleninduzierten Malignoms ist gering. Es besteht kein Infertilitätsrisiko.Schlussfolgerungen:Ist die Zustimmung des Patienten zur prophylaktischen Bestrahlung präoperativ nicht einholbar und der Patient auch postoperativ nicht aufklärbar, werden Aufklärung und Bestrahlung bis drei Tage nach der Operation aufgeschoben. Ist der Patient weiterhin nicht aufklärbar, wird nach Rücksprache mit den Angehörigen die prophlyaktische Bestrahlung durchgeführt. Die Aufklärung des Patienten wird baldmöglichst nachgeholt.