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.

The impact of local control on overall survival after stereotactic body radiotherapy for liver and lung metastases from colorectal cancer: a combined analysis of 388 patients with 500 metastases

BACKGROUND

The aim of this analysis was to model the effect of local control (LC) on overall survival (OS) in patients treated with stereotactic body radiotherapy (SBRT) for liver or lung metastases from colorectal cancer.

METHODS

The analysis is based on pooled data from two retrospective SBRT databases for pulmonary and hepatic metastases from 27 centers from Germany and Switzerland. Only patients with metastases from colorectal cancer were considered to avoid histology as a confounding factor. An illness-death model was employed to model the relationship between LC and OS.

RESULTS

Three hundred eighty-eight patients with 500 metastatic lesions (lung n = 209, liver n = 291) were included and analyzed. Median follow-up time for local recurrence assessment was 12.1 months. Ninety-nine patients with 112 lesions experienced local failure. Seventy-one of these patients died after local failure. Median survival time was 27.9 months in all patients and 25.4 months versus 30.6 months in patients with and without local failure after SBRT. The baseline risk of death after local failure exceeds the baseline risk of death without local failure at 10 months indicating better survival with LC.

CONCLUSION

In CRC patients with lung or liver metastases, our findings suggest improved long-term OS by achieving metastatic disease control using SBRT in patients with a projected OS estimate of > 12 months.

Repeat epidural steroid injections for radicular pain due to lumbar or cervical disc herniation

Aims

The aim of this study was to determine the efficacy of repeat epidural steroid injections as a form of treatment for patients with insufficiently controlled or recurrent radicular pain due to a lumbar or cervical disc herniation.

Patients and Methods

A cohort of 102 patients was prospectively followed, after an epidural steroid injection for radicular symptoms due to lumbar disc herniation, in 57 patients, and cervical disc herniation, in 45 patients. Those patients with persistent pain who requested a second injection were prospectively followed for one year. Radicular and local pain were assessed on a visual analogue scale (VAS), functional outcome with the Oswestry Disability Index (ODI) or the Neck Pain and Disability Index (NPAD), as well as health-related quality of life (HRQoL) using the 12-Item Short-Form Health Survey questionnaire (SF-12).

Results

A second injection was performed in 17 patients (29.8%) with lumbar herniation and seven (15.6%) with cervical herniation at a mean of 65.3 days (sd 46.5) and 47 days (sd 37.2), respectively, after the initial injection. All but one patient, who underwent lumbar microdiscectomy, responded satisfactorily with a mean VAS for leg pain of 8.8 mm (sd 10.3) and a mean VAS for arm pain of 6.3 mm (sd 9) one year after the second injection, respectively. Similarly, functional outcome and HRQoL were improved significantly from the baseline scores: mean ODI, 12.3 (sd 12.4; p < 0.001); mean NPAD, 19.3 (sd 24.3; p = 0.041); mean SF-12 physical component summary (PCS) in lumbar herniation, 46.8 (sd 7.7; p < 0.001); mean SF-12 PCS in cervical herniation, 43 (sd 6.8; p = 0.103).

Conclusion

Repeat steroid injections are a justifiable form of treatment in symptomatic patients with lumbar or cervical disc herniation whose symptoms are not satisfactorily relieved after the first injection. Cite this article: Bone Joint J 2018;100-B:1364–71.

Survival of rats bearing advanced intracerebral F 98 tumors after glutathione depletion and microbeam radiation therapy: conclusions from a pilot project

Background

Resistance to radiotherapy is frequently encountered in patients with glioblastoma multiforme. It is caused at least partially by the high glutathione content in the tumour tissue. Therefore, the administration of the glutathione synthesis inhibitor Buthionine-SR-Sulfoximine (BSO) should increase survival time.

Methods

BSO was tested in combination with an experimental synchrotron-based treatment, microbeam radiation therapy (MRT), characterized by spatially and periodically alternating microscopic dose distribution. One hundred thousand F98 glioma cells were injected into the right cerebral hemisphere of adult male Fischer rats to generate an orthotopic small animal model of a highly malignant brain tumour in a very advanced stage. Therapy was scheduled for day 13 after tumour cell implantation. At this time, 12.5% of the animals had already died from their disease.

The surviving 24 tumour-bearing animals were randomly distributed in three experimental groups: subjected to MRT alone (Group A), to MRT plus BSO (Group B) and tumour-bearing untreated controls (Group C). Thus, half of the irradiated animals received an injection of 100 μM BSO into the tumour two hours before radiotherapy.

Additional tumour-free animals, mirroring the treatment of the tumour-bearing animals, were included in the experiment. MRT was administered in bi-directional mode with arrays of quasi-parallel beams crossing at the tumour location. The width of the microbeams was ≈28 μm with a center-to-center distance of ≈400 μm, a peak dose of 350 Gy, and a valley dose of 9 Gy in the normal tissue and 18 Gy at the tumour location; thus, the peak to valley dose ratio (PVDR) was 31.

Results

After tumour-cell implantation, otherwise untreated rats had a mean survival time of 15 days. Twenty days after implantation, 62.5% of the animals receiving MRT alone (group A) and 75% of the rats given MRT + BSO (group B) were still alive. Thirty days after implantation, survival was 12.5% in Group A and 62.5% in Group B. There were no survivors on or beyond day 35 in Group A, but 25% were still alive in Group B. Thus, rats which underwent MRT with adjuvant BSO injection experienced the largest survival gain.

Conclusions

In this pilot project using an orthotopic small animal model of advanced malignant brain tumour, the injection of the glutathione inhibitor BSO with MRT significantly increased mean survival time.

The SBRT database initiative of the German Society for Radiation Oncology (DEGRO): patterns of care and outcome analysis of stereotactic body radiotherapy (SBRT) for liver oligometastases in 474 patients with 623 metastases

BACKGROUND

The intent of this pooled analysis as part of the German society for radiation oncology (DEGRO) stereotactic body radiotherapy (SBRT) initiative was to analyze the patterns of care of SBRT for liver oligometastases and to derive factors influencing treated metastases control and overall survival in a large patient cohort.

METHODS

From 17 German and Swiss centers, data on all patients treated for liver oligometastases with SBRT since its introduction in 1997 has been collected and entered into a centralized database. In addition to patient and tumor characteristics, data on immobilization, image guidance and motion management as well as dose prescription and fractionation has been gathered. Besides dose response and survival statistics, time trends of the aforementioned variables have been investigated.

RESULTS

In total, 474 patients with 623 liver oligometastases (median 1 lesion/patient; range 1–4) have been collected from 1997 until 2015. Predominant histologies were colorectal cancer (n = 213 pts.; 300 lesions) and breast cancer (n = 57; 81 lesions). All centers employed an SBRT specific setup. Initially, stereotactic coordinates and CT simulation were used for treatment set-up (55%), but eventually were replaced by CBCT guidance (28%) or more recently robotic tracking (17%). High variance in fraction (fx) number (median 1 fx; range 1–13) and dose per fraction (median: 18.5 Gy; range 3–37.5 Gy) was observed, although median BED remained consistently high after an initial learning curve. Median follow-up time was 15 months; median overall survival after SBRT was 24 months. One- and 2-year treated metastases control rate of treated lesions was 77% and 64%; if maximum isocenter biological equivalent dose (BED) was greater than 150 Gy EQD2Gy, it increased to 83% and 70%, respectively. Besides radiation dose colorectal and breast histology and motion management methods were associated with improved treated metastases control.

CONCLUSION

After an initial learning curve with regards to total cumulative doses, consistently high biologically effective doses have been employed translating into high local tumor control at 1 and 2 years. The true impact of histology and motion management method on treated metastases control deserve deeper analysis. Overall survival is mainly influenced by histology and metastatic tumor burden.

Restricted Axillary Staging in Clinically and Sonographically Node-Negative Early Invasive Breast Cancer (c/iT1-2) in the Context of Breast Conserving Therapy: First Results Following Commencement of the Intergroup-Sentinel-Mamma (INSEMA) Trial

Axillary lymph node status remains an important prognostic factor in early breast cancer. It is regarded as an indicator for (neo)adjuvant systemic treatment and postoperative radiotherapy of the regional lymphatics. Commenced in September 2015, the INSEMA trial is investigating whether operative determination of nodal status as part of breast conserving therapy (BCT) for early stage breast cancer (c/iT1-2 c/iN0) can be avoided without reducing oncological safety. After inclusion of 1001 patients there was general acceptance of the complex study design by patients and study doctors so that recruitment for the first randomisation (axillary sentinel lymph node biopsy [SLNB]: yes or no) achieved predicted case numbers. The second randomisation however (SLNB alone versus complete axillary dissection when one or two macrometastases are present at SLNB) recruited fewer cases than expected for the following three reasons: a) the 13 % rate of one or two macrometastases after SLNB in the INSEMA trial collective was lower than expected; b) around 20 % of patients refused the second randomisation; c) there was delayed inclusion of the Austrian study centres, which only recruited for the second randomisation. Lack of knowledge of nodal status when SLNB is avoided represents a new challenge for the postoperative tumour board. In particular decisions on chemotherapy for luminal-like tumours and irradiation of the lymphatics (excluding axilla) must be guided by tumour biological parameters. The INSEMA trial does not provide answers to some important questions, e.g. it remains unclear whether patients without SLNB can be offered partial breast irradiation alone in low-risk situations and whether SLNB can also be avoided in patients with stage T1-2 tumours who have a mastectomy indication.

Stereotactic body radiotherapy for oligo-metastatic liver disease - Influence of pre-treatment chemotherapy and histology on local tumor control

INTRODUCTION

Stereotactic body radiation therapy (SBRT) is applied in the oligometastatic setting to treat liver metastases. However, factors influencing tumor control probability (TCP) other than radiation dose have not been thoroughly investigated. Here we set out to investigate such factors with a focus on the influence of histology and chemotherapy prior to SBRT using a large multi-center database from the German Society of Radiation Oncology.

METHODS

452 SBRT treatments in 363 patients were analyzed after collection of patient, tumor and treatment data in a multi-center database. Histology was considered through random effects in semi-parametric and parametric frailty models. Dose prescriptions were parametrized by conversion to the maximum biologically effective dose using alpha/beta of 10Gy (BED_max).

RESULTS

After adjusting for histology, BED_max was the strongest predictor of TCP. Larger PTV volumes, chemotherapy prior to SBRT and simple motion management techniques predicted significantly lower TCP. The model predicted a BED of 209±67Gy₁₀ necessary for 90% TCP at 2years with no prior chemotherapy, but 286±78Gy₁₀ when chemotherapy had been given. Breast cancer metastases were significantly more responsive to SBRT compared to other histologies with 90% TCP at 2years achievable with BED_max of 157±80Gy₁₀ or 80±62Gy₁₀ with and without prior chemotherapy, respectively.

CONCLUSIONS

Besides dose, histology and pretreatment chemotherapy were important factors influencing local TCP in this large cohort of liver metastases. After adjusting for prior chemotherapy, our data add to the emerging evidence that breast cancer metastases do respond better to hypofractionated SBRT compared to other histologies.

Abstract OT2-04-02: Comparison of axillary sentinel lymph node biopsy versus no axillary surgery in patients with early-stage invasive breast cancer and breast-conserving surgery: A randomized prospective surgical trial. The Intergroup-Sentinel-Mamma (INSEMA)-trial

Background:

Currently, axillary surgery for breast cancer is considered as staging procedure that does not seem to influence breast cancer mortality, since the risk of developing metastasis depends mainly on the biological behaviour of the primary. Based on this, the postsurgical therapy should be considered on the basis of biologic tumor characteristics rather than nodal involvement.

Trial design:

The goal of INSEMA is to show that early-stage breast cancer patients with reduced extent of axillary surgery are not inferior regarding invasive disease-free survival (IDFS) outcome. Patients with planned breast-conserving surgery (BCS) will be first randomized (1:4 ratio) to either no axillary surgery or axillary sentinel lymph node biopsy (SLNB). Patients with SLNB and pN+(sn) status will be secondly randomized (1:1 ratio) to either SLNB alone or completion axillary lymph node dissection (ALND) in cases with less than three involved nodes (one or two macrometastases).

Primary objective:

-IDFS after BCS (non-inferiority question)

Inclusion criteria:

-Written informed consent

-Histologically confirmed unilateral primary invasive carcinoma of the breast (core biopsy)

-Age at least 35 years

-Preoperative imaging techniques with estimated tumor size of maximal 5 cm (iT1/iT2 irrespective of hormone sensitivity or HER2 status)

-Clinically and sonographically tumor-free axilla prior to core biopsy

-In cases with cN0 and iN+, a negative core biopsy or fine needle aspiration biopsy of the suspected lymph node is required

-No clinical evidence for distant metastasis (M0)

-Planned breast-conserving surgery (R0 resection) with postoperative external whole-breast irradiation (conventional fractionation or hypofractionation)

Statistics:

The calculated total case number for per-protocol analyses is 6,740 (5,940 German and 800 Austrian patients), the expected total number of randomized patients is 7,095.

Time lines:

-First patient in: September 2015

-Last patient in: August 2019

-Final analysis: End of 2024

Present accrural: In June 2016, more than 1.000 patients were recruited in Germany and Austria.

Citation Format: Reimer T, von Minckwitz G, Loibl S, Hildebrandt G, Nekljudova V, Schneider-Schranz C, Gerber B. Comparison of axillary sentinel lymph node biopsy versus no axillary surgery in patients with early-stage invasive breast cancer and breast-conserving surgery: A randomized prospective surgical trial. The Intergroup-Sentinel-Mamma (INSEMA)-trial [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT2-04-02.

Nomogram based overall survival prediction in stereotactic body radiotherapy for oligo-metastatic lung disease

BACKGROUND

Radical local treatment of pulmonary metastases is practiced with increasing frequency due to acknowledgment and better understanding of oligo-metastatic disease. This study aimed to develop a nomogram predicting overall survival (OS) after stereotactic body radiotherapy (SBRT) for pulmonary metastases.

PATIENTS AND METHODS

A multi-institutional database of 670 patients treated with SBRT for pulmonary metastases was used as training cohort. Cox regression analysis with bidirectional variable elimination was performed to identify factors to be included into the nomogram model to predict 2-year OS. The calibration rate of the nomogram was assessed by plotting the actual Kaplan-Meier 2-year OS against the nomogram predicted survival. The nomogram was externally validated using two separate monocentric databases of 145 and 92 patients treated with SBRT for pulmonary metastases.

RESULTS

The median follow up of the trainings cohort was 14.3months, the 2-year and 5-year OS was 52.6% and 23.7%, respectively. Karnofsky performance index, type of the primary tumor, control of the primary tumor, maximum diameter of the largest treated metastasis and number of metastases (1 versus >1) were significant prognostic factors in the Cox model (all p<0.05). The calculated concordance-index for the nomogram was 0.73 (concordance indexes of all prognostic factors between 0.54 and 0.6). Based on the nomogram the training cohort was divided into 4 groups and 2-year OS ranged between 24.2% and 76.1% (predicted OS between 30.2% and 78.4%). The nomogram discriminated between risk groups in the two validation cohorts (concordance index 0.68 and 0.67).

CONCLUSIONS

A nomogram for prediction of OS after SBRT for pulmonary metastases was generated and externally validated. This tool might be helpful for interdisciplinary discussion and evaluation of local and systemic treatment options in the oligo-metastatic setting.

KEY MESSAGE

A nomogram for prediction of overall survival after stereotactic body radiotherapy (SBRT) for pulmonary metastases was developed and externally validated. This tool might be helpful for interdisciplinary discussion and evaluation of local and systemic treatment options in the oligo-metastatic setting.

Correlation of pain, functional impairment, and health-related quality of life with radiological grading scales of lumbar degenerative disc disease

BACKGROUND

It is generally believed that radiological signs of lumbar degenerative disc disease (DDD) are associated with increased pain and functional impairment as well as lower health-related quality of life (HRQoL). Our aim was to assess the association of the Modic and Pfirrmann grading scales with established outcome questionnaires and the timed-up-and-go (TUG) test.

METHODS

In a prospective two-center study with patients scheduled for lumbar spine surgery, visual analogue scale (VAS) for back and leg pain, Roland-Morris Disability Index, Oswestry Disability Index and HRQoL, as determined by the Short-Form (SF)-12 and the Euro-Qol, were recorded. Functional mobility was measured with the TUG test. Modic type (MOD) and Pfirrmann grade (PFI) of the affected lumbar segment were assessed with preoperative imaging. Uni- and multivariate logistic regression analysis was performed to estimate the effect size of the relationship between clinical and radiological findings.

RESULTS

Two hundred eighty-four patients (mean age 58.5, 119 (42 %) females) were enrolled. None of the radiological grading scales were significantly associated with any of the subjective or objective clinical tests. There was a tendency for higher VAS back pain (3.48 vs. 4.14, p = 0.096) and lower SF-12 physical component scale (31.2 vs. 29.4, p = 0.065) in patients with high PFI (4-5) as compared to patients with low PFI (0-3). In the multivariate analysis, patients with MOD changes of the vertebral endplates were 100 % as likely as patients without changes to show an impaired TUG test performance (odds ratio (OR) 1.00, 95 % confidence interval (CI) 0.56-1.80, p = 0.982). Patients with high PFI were 145 % as likely as those with low PFI to show an impaired TUG test performance (OR 1.45, 95 % CI 0.79-2.66, p = 0.230).

CONCLUSIONS

There was no association between established outcome questionnaires of symptom severity and two widely used radiological classifications in patients undergoing surgery for lumbar DDD.

Abstract OT2-02-01: Comparison of axillary sentinel lymph node biopsy versus no axillary surgery in patients with early-stage invasive breast cancer and breast-conserving surgery: A randomized prospective surgical trial. The intergroup-sentinel-mamma (INSEMA)-trial

Background:

Currently, axillary surgery for breast cancer is considered as staging procedure that does not seem to influence breast cancer mortality, since the risk of developing metastasis depends mainly on the biological behaviour of the primary. Based on this, the postsurgical therapy should be considered on the basis of biologic tumor characteristics rather than nodal involvement.

Trial design:

The goal of INSEMA is to show that early-stage breast cancer patients with reduced extent of axillary surgery are not inferior regarding invasive disease-free survival (IDFS) outcome. Patients with planned breast-conserving surgery (BCS) will be first randomized (1:4 ratio) to either no axillary surgery or axillary sentinel lymph node biopsy (SLNB). Patients with SLNB and pN+(sn) status will be secondly randomized (1:1 ratio) to either SLNB alone or completion axillary lymph node dissection (ALND) in cases with less than three involved nodes (one or two macrometastases).

Primary objective:

-IDFS after BCS (non-inferiority question)

Inclusion criteria:

-Written informed consent

-Histologically confirmed unilateral primary invasive carcinoma of the breast (core biopsy)

-Age at least 35 years

-Preoperative imaging techniques with estimated tumor size of maximal 5 cm (iT1/iT2 irrespective of hormone sensitivity or HER2 status)

-Clinically and sonographically tumor-free axilla prior to core biopsy

-In cases with cN0 and iN+, a negative core biopsy or fine needle aspiration biopsy of the suspected lymph node is required

-No clinical evidence for distant metastasis (M0)

-Planned breast-conserving surgery (R0 resection) with postoperative external whole-breast irradiation (conventional fractionation or hypofractionation)

Statistics:

Assumptions for first randomization:

-The 5-year IDFS for women with cN0/iN0 axillary lymph nodes and T1/T2 disease is considered to be 88%

-Clinical non-inferiority is defined as the non-SLNB group having a 5-year IDFS of not less than 85% and if the hazard ratio (HR) is less than 1.271 when compared with the SLNB group

The total number of patients in the per-protocol set of the first randomization must be increased from 3,796 to 5,940 (936 events) due to unequal-sample-size design.

Assumptions for second randomization:

-The 5-year IDFS for women with pN+(sn) axillary lymph nodes (1-2 macrometastases) and T1/T2 disease is considered to be 81%

-Clinical non-inferiority is defined as the SLNB alone group having a 5-year IDFS of not less than 76.5% and if the hazard ratio (HR) is less than 1.271 when compared with the completion ALND group

The total number of patients to be included into the per-protocol set for the second randomization will be approximately 1,968. Finally, the calculated total case number for per-protocol analyses is 6,740 (5,940 German and 800 Austrian patients), the expected total number of randomized patients is 7,095.

Time lines:

-First patient in: September 2015

-Last patient in: August 2019

-Final analysis: End of 2024

Funding by Deutsche Krebshilfe (grant no. 110580).

Citation Format: Reimer T, von Minckwitz G, Loibl S, Hildebrandt G, Denkert C, Nekljudova V, Kundt G, Becker D, Gerber B. Comparison of axillary sentinel lymph node biopsy versus no axillary surgery in patients with early-stage invasive breast cancer and breast-conserving surgery: A randomized prospective surgical trial. The intergroup-sentinel-mamma (INSEMA)-trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT2-02-01.

[The parameter "relative survival": Analysis of regional cancer registry data for prostate cancer]

BACKGROUND

There is a lack of comparability of relative survival rates due to differences in regional mortality.

OBJECTIVE

How should relative survival be calculated to be able to compare regional cancer mortality?

MATERIALS AND METHODS

Calculation of relative survival rates of prostate cancer patients from a regional cancer registry using diagnosis year and stage, based on differential mortality tables.

RESULTS

Calculation of relative survival for all prostate cancer patients shows a very slight excess mortality after 5 years compared to a matched general population. Introduction of new imaging techniques and PSA screening led to a change in the distribution of diagnosed stages. Differentiation by stage is therefore essential. Thus, patients with UICC stage I, II, and III have a very low excess mortality, while patients with a UICC stage IV have a significantly higher excess mortality; however, it is very surprising that the excess mortality of patients without specification of the UICC stage is similarly unfavorable as in the case of patients with UICC stage IV.

CONCLUSION

If data from a regional cancer registry are used, adequate mortality tables from the catchment area of the registry should be used as a reference due to regional mortality differences. Thus, progress in patient survival can be more precisely mapped. With respect to prostate cancer patients, differential consideration by stage is also necessary because improved early detection methods has led to a change in the stage distribution and, thus, survival.

[Perampanel in the treatment of a patient with glioblastoma multiforme without IDH1 mutation and without MGMT promotor methylation]

Malignant gliomas like glioblastoma multiforme (GBM) release glutamate which causes excitotoxic death to surrounding neurons, thereby vacating room for tumor expansion. We report the case of a patient with GBM treated with the AMPA receptor blocker Perampanel (PER) in combination therapy for partial seizures. Histological work-up of a biopsy showed the tissue of a GBM without mutation of the isocitrate dehydrogenase 1 (IDH1) and without promotor methylation of the O6-methylguanine-DNA methyltransferase (MGMT). In a group of patients with IDH 1 wild type and non-methylated MGMT a median survival of 199 days after surgery (i. e. 6.5 months) was described. Our patient lived about one year longer. PER rendered our patient seizure-free for at least the last seven months of his life. It was well tolerated and did not increase the toxicity of temozolomide. When choosing an antiepileptic drug (AED) for the treatment of seizures in patients with malignant brain tumors, the efficacy, the tolerability and perhaps possible effects on tumor progression of the AED should be taken into account.

Late inflammatory and thrombotic changes in irradiated hearts of C57BL/6 wild-type and atherosclerosis-prone ApoE-deficient mice

BACKGROUND AND PURPOSE

Radiation-induced heart disease represents a late complication of thoracic radiotherapy. We investigated the inflammatory and thrombotic response after local heart irradiation in wild-type and atherosclerosis-prone mice.

MATERIAL AND METHODS

Atherosclerosis-prone ApoE(-/-) and C57BL/6 wild-type mice were sacrificed 20, 40, and 60 weeks after irradiation with 0.2, 2, 8, or 16 Gy. The expression of CD31, vascular cell adhesion molecule-1 (VCAM-1), thrombomodulin (TM), and CD45 were quantified by immunofluorescence staining of heart tissue sections.

RESULTS

Microvascular density decreased at 40 weeks after 16 Gy in C57BL/6 but not in ApoE(-/-) mice. CD31 expression declined in C57BL/6 mice at 40 weeks (8 Gy), but increased in ApoE(-/-) mice at 20 (2/8/16 Gy) and 60 weeks (16 Gy). Capillary area decreased in C57BL/6 at 40 weeks (8/16 Gy) but increased in ApoE(-/-) mice at 20 weeks (16 Gy). Endocardial VCAM-1 expression remained unchanged. TM-positive capillaries decreased at 40 weeks (8/16 Gy) in C57BL/6 and at 60 weeks (2/16 Gy) in ApoE(-/-) mice. Leukocyte infiltration transiently rose 40 weeks after 8 Gy (only ApoE(-/-)) and 16 Gy. After receiving a low irradiation dose of 0.2 Gy, no significant changes were observed in any of the mouse models.

CONCLUSION

This study demonstrated that local heart irradiation affects microvascular structure and induces inflammatory/thrombotic responses in mice in a dose- and time-dependent manner. Thereby, significant prothrombotic changes were found in both strains, although they were progressive in ApoE(-/-) mice only. Proinflammatory responses, like the increase of adhesion molecules and leukocyte infiltration, were more pronounced and occurred at lower doses in ApoE(-/-) vs. C57BL/6 mice. These findings indicate that metabolic risk factors, such as decreased ApoE lipoproteins, may lead to an enhanced proinflammatory and prothrombotic late response in locally irradiated hearts.

Photoelectric Atomic Absorption Cross Sections for Elements Z = 6 to 54 in the Medium Energy X-Ray Range (5 to 25 keV) — Part I

Photoelectric atomic absorption cross sections have been calculated by means of hydrogen-like eigenfunctions for the atomic K, L, M and N sub-shells of the elements Z = 6 to 54, using revised screening constants and an extension of the theory. The absorption cross sections have been further separated into dipole and quadrupole components so that the numerical data can also be applied to the Borrmann effect.

Röntgen-Wellenfelder in großen Kalkspatkristallen und die Wirkung einer Deformation

Die dem Idealkristall eigentümliche übernormale Durchlässigkeit für RÖNTGEN-Strahlen, welche die v. LAUE-BRAGGSCHE Interferenzbedingung erfüllen, zeigt sich auch an 3 cm dickem Kalkspat noch sehr deutlich. Störung des Kristallgitters vermöge eines Temperaturgradienten läßt die Reflexe rasch an Stärke verlieren.

Normale und anomale Absorption von Röntgen-Strahlen in Germanium und Silicium/Normal and anomalous absorption of X-rays in Germanium and Silicon

A brief discussion of G. Molière's generalized dynamical theory is given with respect to the interpretation of the experimental data|χ⊥ ig/χi0 |obtained by means of the Borrmann effect.

In order to compare theory and experiment photoelectric absorption cross sections for Silicon and Germanium have been calculated over the X-ray energy range from 5 to 25 keV. Linear absorption coefficients measured by us and other authors agree with theory within a few per cent.

Taking the Debye-Waller factor into account, the same theoretical data have been used to calculate |χ⊥ ig/χi0 | for Ge and Si. The agreement with extensive measurements of the Borrmann effect in Ge is very good in most cases. The experiments presented in this paper confirm the existence of the electric quadrupole transitions within the photoelectric effect.

Late effects of local irradiation on the expression of inflammatory markers in the Arteria saphena of C57BL/6 wild-type and ApoE-knockout mice

Combined action of irradiation (IR), shear stress, and high blood pressure is well recognized to induce damage to vasculature, while data on pathological effects of IR in large peripheral vessels with low blood pressure are scarce. The purpose of the present study was hence to investigate time- and dose-dependent effects of local IR on inflammatory and prothrombotic processes in the Arteria (A.) saphena of C57BL/6 wild-type and apolipoprotein E (ApoE)-knockout mice. Single doses of 2, 5, 8, 10, or 16 Gy were locally delivered to the A. saphena of the left leg of the animals. The expression of CD31, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, monocyte chemoattractant protein-1 (MCP-1), and thrombomodulin (TM) was quantified by semiautomatic TissueFax fluorescence analysis in frozen arterial sections. Follow-up periods were 3, 6, 9, 12, or 18 months. Protein expression in the arterial wall displayed dose-dependent changes. Proinflammatory reactions were observed for CD31, E-selectin, ICAM, and VCAM already at doses of 2 Gy. Anti-inflammatory changes were detected for MCP-1 and TM. The effects were more pronounced in wild-type versus ApoE(-/-) mice. Changes remain mostly transient up to 16 Gy. Dose- and time-dependent changes in inflammatory and thrombotic mediators in the wall of the A. saphena were found after local IR but did not transform into histopathological consequences.

Low-dose radiation exposure and protection against atherosclerosis in ApoE(-/-) mice: the influence of P53 heterozygosity

We recently described the effects of low-dose γ-radiation exposures on atherosclerosis in genetically susceptible (ApoE(-/-)) mice with normal p53 function. Doses as low as 25 mGy, given at either early or late stage disease, generally protected against atherosclerosis in a manner distinctly nonlinear with dose. We now report the influence of low doses (25-500 mGy) on atherosclerosis in ApoE(-/-) mice with reduced p53 function (Trp53(+/-)). Single exposures were given at either low or high dose rate (1 or 150 mGy/min) to female C57BL/6J ApoE(-/-) Trp53(+/-) mice. Mice were exposed at either early stage disease (2 months of age) and examined 3 or 6 months later, or at late stage disease (7 months of age) and examined 2 or 4 months later. In unirradiated mice, reduced p53 functionality elevated serum cholesterol and accelerated both aortic root lesion growth and severity in young mice. Radiation exposure to doses as low as 25 mGy at early stage disease, at either the high or the low dose rate, inhibited lesion growth, decreased lesion frequency and slowed the progression of lesion severity in the aortic root. In contrast, exposure at late stage disease produced generally detrimental effects. Both low-and high-dose-rate exposures accelerated lesion growth and high dose rate exposures also increased serum cholesterol levels. These results show that at early stage disease, reduced p53 function does not influence the protective effects against atherosclerosis of low doses given at low dose rate. In contrast, when exposed to the same doses at late stage disease, reduced p53 function produced detrimental effects, rather than the protective effects seen in Trp53 normal mice. As in the Trp53 normal mice, all effects were highly nonlinear with dose. These results indicate that variations in p53 functionality can dramatically alter the outcome of a low-dose exposure, and that the assumption of a linear response with dose for human populations is probably unwarranted.