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Klaus-Rüdiger Trott

Publications and source records attributed to Klaus-Rüdiger Trott.

7 recordsLinked to original sources
PubMed2007

Radiation-induced cardiovascular diseases: is the epidemiologic evidence compatible with the radiobiologic data?

The Life Span Study of Japanese atomic bomb survivors demonstrates that radiation exposure significantly increased the risk of developing ischemic heart disease, in particular myocardial infarction. Similarly, epidemiologic investigations in very large populations of patients who had received postoperative radiotherapy for breast cancer or for peptic ulcer demonstrate that radiation exposure of the heart with an average equivalent single dose of approximately 2 Gy significantly increased the risk of developing ischemic heart disease more than 10 years after irradiation. These epidemiologic findings are compatible with radiobiologic data on the pathogenesis of radiation-induced heart disease in experimental animals. The critical target structure appears to be the endothelial lining of blood vessels, in particular arteries, leading to early functional alterations such as pro-inflammatory responses and other changes, which are slowly progressive. Research should concentrate on the interaction of these radiation-induced endothelial changes with the early stages of age-related atherosclerosis to develop criteria for optimizing treatment plans in radiotherapy and also potential interventional strategies.

Animals↗
PubMed2006

Estimation of cancer risks from radiotherapy of benign diseases.

BACKGROUND: The effective-dose method which was proposed by the ICRP (International Commission of Radiation Protection) for the estimation of risk to the general population from occupational or environmental, low-dose radiation exposure is not adequate for estimating the risk of cancer induction by radiotherapy of malignant or nonmalignant diseases. METHODS: The risk of cancer induction by radiotherapy of benign diseases should be based on epidemiologic data directly derived from follow-up studies of patients who had been given radiotherapy for nonmalignant diseases in the past. RESULTS: Risk factors were derived from epidemiologic studies of patients treated with irradiation for nonmalignant diseases to be used for selecting treatment options and optimizing treatment procedures. CONCLUSION: In most cases, cancer risks estimated by the effective-dose method may overestimate the true risks by one order of magnitude, yet in other cases even may underestimate it. The proposed method using organ-specific risk factors may be more suitable for treatment planning.

Adolescent↗
PubMed2005

Dose to bone marrow using IMRT techniques in prostate cancer patients.

PURPOSE: To investigate the dose distribution in active bone marrow of patients undergoing intensity-modulated radiotherapy (IMRT) for prostate cancer and compare it to the distribution in the same patients, if they had been treated using conformal plans, in order to develop criteria for optimization to minimize the estimated risk of secondary leukemia. PATIENTS AND METHODS: Mean bone marrow doses were calculated for ten patients with localized prostate cancer who underwent whole-pelvis IMRT and compared to three-dimensional conformal (3-D CRT) plans prepared for the same patients. Also for comparison, the IMRT and 3-D CRT plans were produced to simulate the treatment of the prostate gland only. To measure the dose to extrapelvic bone marrow, three thermoluminescent diode (TLD) chips were placed in the middle of the sternum region inside the Rando phantom. RESULTS: For both the pelvic and prostate-only volumes, the IMRT plans were superior to 3-D CRT plans in reducing the high dose volume to the rectum, the bladder and the small bowel while maintaining acceptable coverage of the planning target volume (PTV). For the pelvic treatment group the IMRT plans, compared to 3-D CRT, reduced the high dose volume (> 20 Gy) to os coxae, which is the main contributor of dose to pelvic bone marrow, but increased the middle dose volume (10-20 Gy). No statistically significant differences were observed for lower dose volumes (< 5 Gy). For the prostate-only treatment the IMRT plan increased the high dose volume and slightly decreased the low dose volume of pelvic bone marrow. However, for both treatments the leakage dose to extrapelvic sites was higher by a factor of 2 in IMRT plans. CONCLUSION: There are significant differences in the dose-volume histograms of bone marrow doses from 3-D CRT and from IMRT. Pronounced dose inhomogeneity reduces the risk of leukemia compared to homogeneous radiation exposure of the bone marrow. The mean bone marrow dose is therefore not a useful criterion to judge plan quality, since scattered low doses to distant sites may be more critical than the high dose volumes receiving > 10 Gy. The number of monitor units needed to deliver an IMRT plan affects leakage dose and their incorporation into planning constraints should be considered.

Bone Marrow↗
PubMed2005

Radiation treatment of acute inflammation in mice.

PURPOSE: Low-dose radiotherapy (RT) has often been used effectively for the treatment of a variety of benign diseases, particularly those with acute inflammatory features. Here we report findings on radiation treatment of acute inflammation using a murine carrageenin air pouch model. MATERIALS AND METHODS: Air pouches raised on the dorsal surface of mice were injected with lambda carrageenin and were irradiated 6 h later with doses ranging from 0-5 Gy. Treatment success was evaluated at various times thereafter by volume of exudate and number of inflammatory cells, and levels of inflammation-related cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1beta) and transforming growth factor beta-1 (TGFbeta-1), and expression of inducible nitric oxide synthase (iNOS), heme oxygenase-1 (HO-1), cyclooxygenase-2 (COX-2) and inducible heat shock protein 70 (HSP70) as determined by enzyme-linked immunosorbent assay (ELISA) and Western blotting, respectively. RESULTS: Crude inflammatory parameters such as the amount of exudates and number of inflammatory cells remained largely unaffected by radiation or were even a slightly and transiently increased. However, the expression of iNOS was attenuated by radiation concomitant with an increase in the levels of HO-1 and HSP70. Cytokine levels varied with the radiation dose and the time point. CONCLUSIONS: Ionizing radiation, even at low doses, functionally modulates inflammatory cells. Our findings indicate possible mechanisms as to how low-dose radiation may exert anti-inflammatory effects and provide the first evidence that heat shock proteins may be involved in this response.

Acute Disease↗
PubMed2004

[Offsprings of preconceptionally irradiated parents. Final report of a longitudinal study 1976-1994 and recommendations for patients' advisory].

BACKGROUND: Many young adults with cancer of good prognosis seek advice from their doctors, because they are concerned about their ability to have children and about potential hereditary diseases in the children conceived or fathered after cancer therapy. PATIENTS AND METHODS: Results of repeated examinations of 61 children over a period of 20 years are reported. One of their parents had received radiotherapy for malignant disease (only three had additional chemotherapy). Radiation doses to the gonads ranged from 0.01 to 2 Gy. The most frequent indications for radiotherapy were Hodgkin's disease (n=25), seminomas (n=7), thyroid cancer (n=3), and malignant melanomas (n=3) RESULTS: There was a trend to premature birth with 52.5% of the babies born before term. Yet, all had normal birth weight and delivery was inconspicuous. The skeletal maturation was retarded, but development was still in the normal range of German children. There were no chromosome aberrations, normal mental and intellectual development, and no malignancy among these children. A trend to an increased frequency of developmental disturbances and four moderately severe malformations were observed; however, no direct association with radiation treatment could be demonstrated. One child had a balanced translocation (5;17) which it inherited from the unirradiated parent. CONCLUSION: During the first consultation of young adult cancer patients, before the start of treatment, the problems of fertility and of therapy-induced mutations and hereditary diseases as well as developmental damage of the offspring need to be addressed directly by the radiation oncologist. Decisions on cryoconservation of sperm, fixation of the ovaries and dosimetry of the gonads during radiotherapy have to be made before the start of treatment. The rate of radiation-induced hereditary diseases and developmental damage in the children conceived or fathered after curative radiotherapy of one parent is estimated to increase by <0.1% (after gonadal exposure of 1 Gy). However, at present, heritable damage potentially induced by chemotherapy cannot be adequately quantified yet.

Abnormalities, Radiation-Induced↗
PubMed2002

Chromosomal aberration in peripheral lymphocytes and doses to the active bone marrow in radiotherapy of prostate cancer.

BACKGROUND AND PURPOSE: Radiotherapy plays an important role in the management of prostate cancer. Epidemiological data indicate a small but significant risk of radiation-induced leukemia after radiotherapy which might be related to the high mean bone marrow dose associated with radiotherapy of prostate cancer. The purpose of the study was to investigate the relation between the mean bone marrow dose and unstable chromosome aberrations in peripheral blood lymphocytes in patients undergoing conformal radiotherapy for prostate cancer as a possible indicator of risk. Endometrial cancer patients were also included for comparison. PATIENTS AND METHODS: Nine patients, six with prostate cancer (60-73 years old) and three with endometrial cancer (61-81 years old) treated with radiotherapy were included in the study. The non-bony spaces inside the pelvic bones were outlined on every CT slice using the treatment planning system and mean doses to the bone marrow calculated. Blood samples of the patients were obtained at different times before, during and at the end of treatment. Lymphocytes were cultured in the usual way and metaphases scored for dicentric aberrations. RESULTS: 46 samples from nine patients were obtained. The mean number of metaphases analyzed per sample was 180 with a range from 52 to 435. The mean bone marrow doses for prostate cancer patients ranged from 2.8 to 4.2 Gy and for endometrial cancer patients from 12.8 to 14.8 Gy. The aberration yield increased with the planning target volume and the mean bone marrow dose. CONCLUSION: The yield of dicentric aberrations for prostate cancer patients correlated closely with the mean bone marrow dose albeit the induction of dicentrics occurred in mature T lymphocytes most of which were probably in transit through the irradiated volumes. Therefore, the observed relationship between dicentrics and mean bone marrow doses are indirect.

Adult↗