Integration of radiation oncology teaching in medical studies by German medical faculties due to the new licensing regulations : An overview and recommendations of the consortium academic radiation oncology of the German Society for Radiation Oncology (DEGRO)

The new Medical Licensing Regulations 2025 (Ärztliche Approbationsordnung, ÄApprO) will soon be passed by the Federal Council (Bundesrat) and will be implemented step by step by the individual faculties in the coming months. The further development of medical studies essentially involves an orientation from fact-based to competence-based learning and focuses on practical, longitudinal and interdisciplinary training. Radiation oncology and radiation therapy are important components of therapeutic oncology and are of great importance for public health, both clinically and epidemiologically, and therefore should be given appropriate attention in medical education. This report is based on a recent survey on the current state of radiation therapy teaching at university hospitals in Germany as well as the contents of the National Competence Based Learning Objectives Catalogue for Medicine 2.0 (Nationaler Kompetenzbasierter Lernzielkatalog Medizin 2.0, NKLM) and the closely related Subject Catalogue (Gegenstandskatalog, GK) of the Institute for Medical and Pharmaceutical Examination Questions (Institut für Medizinische und Pharmazeutische Prüfungsfragen, IMPP). The current recommendations of the German Society for Radiation Oncology (Deutsche Gesellschaft für Radioonkologie, DEGRO) regarding topics, scope and rationale for the establishment of radiation oncology teaching at the respective faculties are also included.

New flow relaxation mechanism explains scour fields at the end of submarine channels

Particle-laden gravity flows, called turbidity currents, flow through river-like channels across the ocean floor. These submarine channels funnel sediment, nutrients, pollutants and organic carbon into ocean basins and can extend for over 1000’s of kilometers. Upon reaching the end of these channels, flows lose their confinement, decelerate, and deposit their sediment load; this is what we read in textbooks. However, sea floor observations have shown the opposite: turbidity currents tend to erode the seafloor upon losing confinement. Here we use a state-of-the-art scaling method to produce the first experimental turbidity currents that erode upon leaving a channel. The experiments reveal a novel flow mechanism, here called flow relaxation, that explains this erosion. Flow relaxation is rapid flow deformation resulting from the loss of confinement, which enhances basal shearing of the turbidity current and leads to scouring. This flow mechanism plays a key role in the propagation of submarine channel systems.

The nature of erosion featured at the outlet of submarine channels is still a topic of debate. Here the authors present, based on scaled experiments, a novel flow mechanism for turbidity currents at the end of submarine channels and for the first time describe their erosional character.

Effects of radiation on the expression of adhesion molecules and cytokines in a static model of human dermal microvascular endothelial cells

BACKGROUND

Radiation-induced wound healing complications represent an important clinical problem. Microvascular compromise is an important component of its pathogenesis and the microvascular endothelial cell is the key representative affected at the cellular level.

MATERIAL AND METHODS

Human dermal microvascular endothelial cells (HDMEC) were cultured and irradiated with doses of 2 to 12 Gy. Cell density was determined 48 h after radiation using a semi-automated cell counting system. Levels of interleukin-6 (IL-6), basic fibroblast growth factor (FGF), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in the supernatants of HDMEC were determined by polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Non irradiated HDMEC were used as controls.

RESULTS

Cell density was significantly impaired in irradiated cells compared to non irradiated controls. Radiation resulted in significant elevation of levels of IL-6, FGF, ICAM-1 and VCAM-1 in the supernatants of HDMEC in a dose dependent manner.

CONCLUSION

The inflammatory response observed clinically after radiation seems to correlate with elevated expression of cytokines and adhesion molecules by microvascula endothelial cells. The model of HDMEC documents the impairment of microcirculation. These in vitro changes may enhance our understanding of the pathomechanisms leading to radiation-induced vasculitis and associated wound healing problems.

Childhood craniopharyngioma - changes of treatment strategies in the trials KRANIOPHARYNGEOM 2000/2007

BACKGROUND

Prognosis in childhood cranio-pharyngioma, is frequently impaired due to sequelae. Radical surgery was the treatment of choice for decades. Even at experienced facilities radical surgery can result in hypothalamic disorders such as severe obesity.

OBJECTIVE

We analyzed, whether treatment strategies for childhood craniopharyngioma patients recruited in GPOH studies have changed during the last 12 years.

MATERIALS AND METHODS

We compared the grade of pre-surgical hypothalamic involvement, treatment, degree of resection and grade of surgical hypothalamic lesions between patients recruited in KRANIOPHARYNGEOM 2000 (n=120; 2001-2007) and KRANIOPHARYNGEOM 2007 (n=106; 2007-2012).

RESULTS

The grade of initial hypothalamic involvement was similar in patients treated 2001-2007 and 2007-2012. The realized treatment was more radical (p=0.01) in patients recruited 2001-2007 (38%) when compared with patients treated 2007-2012 (18%). In patients with pre-surgical involvement of anterior/posterior hypothalamic areas, the rate of hypothalamus-sparing operations resulting in no (further) hypothalamic lesions was higher (p=0.005) in patients treated 2007-2012 (35%) in comparison with the 2001-2007 cohort (13%). Event-free-survival rates were similar in both cohorts.

CONCLUSIONS

A trend towards less radical surgical approaches is observed, which was accompanied by a reduced rate of severe hypothalamic lesions. Radical surgery is not an appropriate treatment strategy in patients with hypothalamic involvement. Despite previous recommendations to centralize treatment at specialized centers, a trend towards further decentralization was seen.

IMPACTO DA IDADE AO PARTO NO DESEMPENHO PRODUTIVO E REPRODUTIVO EM VACAS HOLANDESAS PRIMÍPARAS

Com o objetivo de determinar o impactoda idade ao primeiro parto (IPP) no desempenhoprodutivo e reprodutivo de vacas leiteiras, 32 novilhasHolandesas foram distribuídas em dois gruposde acordo com a IPP: 16 novilhas foram classificadascomo “Novas”, com IPP inferior a 700 dias e16 novilhas foram classificadas como “Velhas”, comIPP superior a 700 dias. Dados de desempenhoprodutivo e reprodutivo foram analisados por análisede variância usando o procedimento GLM doSAS. Novilhas de primeiro parto que pariram antesdos 700 dias de idade apresentaram menor produçãode leite (P<0,05) (novas-9.900 vs. 11.618 kgvelhas),menor produção de gordura (P<0,05) (373vs. 425 kg) e menor produção de proteína (P<0,05)(279 vs. 307 kg) do que novilhas que pariram apósos 700 dias de idade. Os teores de gordura e proteínano leite não variaram significativamente entreos dois grupos de primíparas: 3,80% vs. 3,96% degordura e 2,81% vs. 2,81% de proteína, respectivamentepara Novas e Velhas. Relativamente aosdados de desempenho reprodutivo, novilhas quepariram antes dos 23 meses de idade, apresentarammelhores índices reprodutivos (P<0,05) do quenovilhas que pariram mais tarde, isto é, após os 23meses de idade ou seja: houve menor número dedias entre o parto e o 1º cio (48,9 vs. 70,4 dias), menor período de serviço (69,8 vs. 110,2 dias) emenor intervalo entre partos (359,2 vs. 390,1 dias).

[Requirements and performance profile of the Paediatric Radiation Oncology Working Group (APRO): evaluation of the present situation and description of future developments]

BACKGROUND

Radiation therapy is an integral component in the management of childhood malignancies and undergoes a continuous process of optimization within the prospective trials of the GPOH. At present there are approximately 20 active protocols, some specifying radio-oncological study questions, in which about 500 to 600 children annually are given radiotherapy.

MATERIALS/METHODS

The Pediatric Radiation Oncology Working Group (APRO) of the German Society for Radiation Oncology (DEGRO) represents the organizational link between GPOH and DEGRO. Their activities range from phrasing guidelines of radio-oncological therapy, through writing a protocol for a prospective study on radiation-induced late effects (RISK--in co-operation with GPOH, 695 patients registered so far) and organizing meetings for information transfer, to implementing radio-oncology within the prospective studies of the GPOH by establishing study chairs for radio-oncology when radio-oncological questions are a primary focus and/or to function as a reference institution for quality assurance. These activities also include individual case consultations outside the study proper. Twice annually the members of the APRO meet for an update on current knowledge and future directions where a representative of the GPOH is invited to contribute special aspects of pediatric oncology.

CONCLUSIONS

In the future, modern technology (intensity modulated radiotherapy, proton therapy, inclusion of imaging in treatment planning) will be part of disease management in pediatric oncology. A working group for modern radiotherapy technology was established to enhance this development. Prospective studies of the GPOH with primary or secondary radio-oncological questions require the implementation of corresponding tasks (documentation, monitoring, etc.) in order to meet future demands on clinical trials and to achieve the aims of the protocol. Consequently adequate financial support is indispensable.

Überleben mit hämatogen metastasierten HNO-Tumoren

QUESTIONS

The objective of this retrospective analysis was to investigate parameters with a potential impact on survival in a collective of 114 patients with distant metastatic disease after head and neck cancer.

PATIENTS AND METHODS

The primary endpoint was the survival with distant metastatic disease, the secondary endpoint was overall survival. Primary therapy, local recurrence, second neoplasms, palliative chemotherapy (CHT) and radiotherapy (RT), as well as Karnofsky performance status (KPS) at the time of diagnosis of the metastases were analyzed as potential impact parameters using the log-rank test with subsequent Cox regression analysis.

RESULTS

Palliative CHT (P=0.0020) and KPS (P=0.0011) had a significant positive impact on the median survival probability with metastases (8.2 months) using the log-rank test, KPS at the time of diagnosis of metastases remained as an independent prognostic parameter in the Cox regression (P=0.0013). Primary therapy, local tumor control and KPS had a significant positive influence on the median overall survival probability (18.5 months) univariately (P=0.0139, P=0.0106, P= 0.0096) and multivariately (P=0.0123, and P=0.0063, P=0.0197, respectively).

CONCLUSIONS

KPS at the time of diagnosis of metastases is an independent prognostic parameter for both endpoints. Lacking evidence for life prolongation, palliative therapies should therefore first and foremost focus on the stabilization of the KPS.

Relapse Pattern After Complete Resection and Early Progression After Incomplete Resection of Childhood Craniopharyngioma

In HIT Endo data on therapy and prognosis of 306 patients with childhood craniopharyngioma (CP) were analyzed. The 5 years-overall survival rate was 94 +/- 4 % in irradiated patients and 93 +/- 5 % in non-irradiated patients. Aims of the prospective study KRANIOPHARYNGEOM 2000 were to collect data on the incidence and time course of relapses after complete surgery and tumour progressions after incomplete resection. Furthermore, the impact of irradiation therapy (XRT) on tumour relapse and recurrence rates was analyzed. Since 2001 ninety-eight patients with CP were recruited at a median age at diagnosis of 9.9 years ranging from 1.8 to 18.0 years. Complete resection was achieved in 44 %, incomplete resection in 54 %. XRT was performed in 24 of 98 CP patients; in 10 early after incomplete resection, in 14 of 24 after progression of residual tumour or relapse, in 3 of 14 after second surgery of relapse. XRT was performed at a median age of 12.0 years ranging from 5.0 to 18.9 years and in median after an interval of 9 months after first diagnosis. The analysis of event-free survival rates (EFS) in patients with CP showed a high rate of early events in terms of tumour progression after incomplete resection (3y-EFS: 0.22 +/- 0.09) and relapses after complete resection (3y-EFS: 0.60 +/- 0.10) during the first three years of follow-up. A high rate of early events (1y-EFS: 0.78 +/- 0.10; 2y-EFS: 0.57 +/- 0.15) was also found for patients after XRT (3 cystic progressions, 3 progressions of solid tumour; in 24 patients after XRT). We conclude that tumour progression and relapse are frequent and early events even in irradiated patients. Monitoring of cerebral imaging and clinical status is recommended in follow-up of patients with childhood CP. In order to analyze the appropriate time point of XRT after incomplete resection, QoL, EFS and overall survival in patients (age > or = 5 years) will be analyzed in KRANIOPHARYNGEOM 2007 after stratified randomization of the time point of irradiation after incomplete resection (early irradiation versus irradiation at progression of residual tumour).

Impact of the Narcotrend Index on propofol consumption and emergence times during total intravenous anaesthesia with propofol and remifentanil in children: a clinical utility study

BACKGROUND AND OBJECTIVE

The electroencephalographic Narcotrend Index (NI) is a measure of the hypnotic component of general anaesthesia. The purpose of this study was to evaluate the impact of Narcotrend guidance on propofol consumption and emergence times in children receiving total intravenous anaesthesia with propofol and remifentanil.

METHODS

Thirty children, aged 1-11 yr, scheduled for paediatric urological surgery were enrolled. Remifentanil was given to all patients at a constant infusion rate of 0.3 microg kg [-1] min[-1] throughout anaesthesia. Patients were randomly allocated to receive a continuous propofol infusion adjusted either according to a conventional clinical practice (Group C: n=15) or guided by Narcotrend monitoring (Group NI: n=15; target NI 60+/-5). All patients were connected to the Narcotrend Monitor, but in Group C the anaesthetist was blinded to the screen of the monitor. Propofol consumption (mg kg[-1]h[-1]) and emergence times (min) were the primary and secondary outcome measures.

RESULTS

Propofol consumption (median [inter-quartile range]) was significantly lower in Group NI compared to Group C (NI: 7.0 [6.4--8.2] vs. C: 9.3 [8.3--11.0] mg kg[-1]h[-1]; P<0.001), whereas Log-Rank-analysis revealed no intergroup difference in emergence times (Group NI: mean [95% confidence interval (CI)] 12.8 [11.2--14.4] min; Group C: 16.4 [12.6--20.2] min; P=0.10). Haemodynamic variables remained stable within age-related limits, and there were no observations of adverse events, especially no clinical signs of intraoperative awareness in any patient.

CONCLUSION

Narcotrend monitoring for guidance of propofol/remifentanil anaesthesia in children results in reduced propofol consumption compared to a conventional clinical practice.

Radiation-induced suppression of the Bmp2 signal transduction pathway in the pluripotent mesenchymal cell line C2C12: an in vitro model for prevention of heterotopic ossification by radiotherapy

Heterotopic ossification is a common complication after total hip replacement. Clinical studies showed the effectiveness of radiation for prevention of heterotopic ossification. The mechanism of radiotherapy responsible for the reduction of heterotopic ossification is unclear. The purpose of this study was to study an analogue model showing a time- and dose-dependent effect of radiation. Using cells of the defined embryonic mouse cell line C2C12, the influence of ionizing radiation on the Bmp-induced signal cascade leading to osteogenic differentiation was analyzed. Binding of iodinated Bmp2 to the receptors, Smad1 activation, and alkaline phosphatase (ALP) activity were determined in cells with or without irradiation. The cytotoxic effect of radiotherapy was evaluated using viability tests. Radiotherapy reduced formation of the Bmp2/Bmp receptor complex. This effect was dependent on dose. The phosphorylation (activation) of Smad1 decreased after irradiation in a time-dependent manner, whereas the level of total Smads was not influenced by radiotherapy. The ALP activity decreased after radiotherapy. A dose of 7 Gy delivered 6 h before or after incubation with Bmp resulted in about a 30% decrease in ALP activity. No signs of cytotoxic effects were observed within the time window studied using doses of 0 to 20 Gy. The time- and dose-dependent effect of radiotherapy for prevention of heterotopic ossification known from the results of clinical studies has an analogue in the C2C12 cell model. The primary mechanism of radiotherapy seems to be an influence on cellular responsiveness to the Bmp2-induced osteoblastic differentiation. The results suggest a down-regulation of the Bmp2/receptor complex.

Radiation-induced reduction of BMP-induced proteoglycan synthesis in an embryonal mesenchymal tissue equivalent using the chicken "limb bud" test

PURPOSE

Heterotopic ossification (HO) is a common complication following total hip replacement. Clinical studies showed the effectiveness of irradiation for prevention of heterotopic ossification. The mechanism of radiotherapy responsible for the reduction of heterotopic ossification is unclear. The purpose of this study was to find a suitable cell system, which can reproduce in-vitro data resulting from clinical in-vivo studies. The establishment of such a cell model allows detailed analyses of the mechanism of radiotherapy.

METHOD

The chicken limb bud test was used as an in-vitro model. The cells acquired by the limb bud test were irradiated with different doses (0 Gy, 3 Gy, 7 Gy, 10 Gy, 20 Gy). Irradiation was set either 1 hour before, or 1 or 3 days after BMP-2 incubation. The synthesis of proteoglycans (PGS) upon treatment with bone morphogenetic protein (BMP)-2 was measured in cells incubated with BMP-2 for 4 days followed by 35SO4(2-) labeling for 6 hours. Labeled proteoglycans were precipitated using Alcian blue and measured in a raytest radio-TLC analyzer. The incubation with BMP-2 was defined to correlate the in-vivo stimulus meaning the operation.

RESULTS

The proteoglycan synthesis was significantly reduced by irradiation 1 hour before or 1 day after BMP-2 incubation, if the dosage was at least 7 Gy. Higher doses than 7 Gy did not lead to lower proteoglycan levels. There was only a trend for a reduction of proteoglycan synthesis by 3 Gy irradiation, but no significant difference compared to the non-irradiated control. An irradiation 3 days after BMP-2 incubation had no effect on proteoglycan.

CONCLUSION

A dose and time dependent effect of radiation on BMP-2-induced proteoglycan synthesis was observed. Therefore the results of clinical in-vivo studies were reproduced exactly by the limb bud test. We established an in-vitro cell model to analyze the mechanism of the prevention of heterotopic ossification by radiotherapy on cellular or sub-cellular level.

[Are morphologic changes in skeletal muscles of patients with malignant hyperthermia diagnostically useful?]

Malignant Hyperthermia (MH) represents a functional myopathy triggered by volatile anesthetics and depolarizing muscle relaxants, and leading to metabolic disturbances of intracellular Calcium homeostasis. Central-Core-like-structures (CCLS) were recently described as central defects in enzyme-histochemical stains and well correlated to the autosomal-dominant MH-predisposition. We studied the correlation of a MH-predisposition with specific myopathological signs. Skeletal muscles of suspected MH-individuals were histochemically stained by SDH-, NADH-, COX-, Gomori-Trichrome-, ATPase-, Acid Phosphatase-, Oil-red O- und PAS-stain und evaluated without knowing MH-diagnosis by the in-vitro-contracture test. Out of 118 patients (30% MHS ["susceptible"], 63% MHN [normal], 7% MHE ["equivocal"]) 19% revealed pathological findings corresponding to CCLS. 45% of these findings were associated with MHS/MHE. With HE-staining internal nuclei were not specific, but increased with the probability of MHS/MHE from 24% to 80%. Central Cores were correlated in 100% with MHS/MHE (4 out of 118 patients). CCLS were found with about similar frequency in skeletal muscle of MHS/MHE and MHN individuals. Internal nuclei were, however, not specifically, associated with MHS. In contrast, Central Cores correlated significantly with MHS/MHE diagnosis. In conclusion, histopathological findings in skeletal muscle seem to be a reliable marker for MH-predisposition only with Central Cores.