| 11. |
- Matson, Sophia, et al.
(författare)
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Nonattendance in mammographic screening: a study of intraurban differences in Malmo, Sweden, 1990-1994
- 2001
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Ingår i: Cancer Detection and Prevention. - 0361-090X. ; 25:2, s. 132-137
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Tidskriftsartikel (refereegranskat)abstract
- Mammographic screening may reduce breast cancer mortality. Not all women, however, come for examination. The objective in this study from Malmo has been to assess extent to which the rate of nonattendance varies between residential areas with different sociodemographic profiles. The study is based on 32,605 women, 45 to 68 years old and living in 17 areas, who between 1990 and 1994 were invited to screening. Between age groups, the age-specific nonattendance rate ranged from 31% to 35 % (P < .01). The nonattendance rate was highest for women 65 years or older. Between residential areas, age-adjusted nonattendance rates ranged from 23% to 43% (P < .01). A socioeconomic score was developed to express the socioeconomic circumstances in the residential areas and ranged from -7.18 in the most deprived area to 5.01 in the least. Nonattendance covaried in an inverse fashion with the socioeconomic score (r = -0.78; P < .01). One of three women in this urban population did not accept the invitation to mammographic screening. Our conclusion is that women in areas with less favorable circumstances seem to be less willing to participate.
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| 12. |
- Capala, J, et al.
(författare)
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Boron neutron capture therapy for glioblastoma multiforme : Clinical studies in Sweden
- 2003
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Ingår i: Journal of Neuro-Oncology. - 1573-7373. ; 62:1, s. 135-144
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Tidskriftsartikel (refereegranskat)abstract
- A boron neutron capture therapy (BNCT) facility has been constructed at Studsvik, Sweden. It includes two filter/moderator configurations. One of the resulting neutron beams has been optimized for clinical irradiations with a filter/moderator system that allows easy variation of the neutron spectrum from the thermal to the epithermal energy range. The other beam has been designed to produce a large uniform field of thermal neutrons for radio-biological research. Scientific operations of the Studsvik BNCT project are overseen by the Scientific Advisory Board comprised of representatives of major universities in Sweden. Furthermore, special task groups for clinical and preclinical studies have been formed to facilitate collaboration with academia. The clinical Phase II trials for glioblastoma are sponsored by the Swedish National Neuro-Oncology Group and, presently, involve a protocol for BNCT treatment of glioblastoma patients who have not received any therapy other than surgery. In this protocol, p-boronophenylalanine (BPA), administered as a 6-h intravenous infusion, is used as the boron delivery agent. As of January 2002, 17 patients were treated. The 6-h infusion of 900 mg BPA/kg body weight was shown to be safe and resulted in the average blood-boron concentration of 24 μg/g (range: 15-32 μg/g) at the time of irradiation (approximately 2-3 h post-infusion). Peak and average weighted radiation doses to the brain were in the ranges of 8.0-15.5 Gy(W) and 3.3-6.1 Gy(W), respectively. So far, no severe BNCT-related acute toxicities have been observed. Due to the short follow-up time, it is too early to evaluate the efficacy of these studies.
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| 13. |
- Tsuda, S, et al.
(författare)
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Flat and depressed colorectal tumours in a southern Swedish population: a prospective chromoendoscopic and histopathological study.0
- 2002
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Ingår i: Gut. - : BMJ. - 1468-3288 .- 0017-5749. ; 51:4, s. 550-555
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Tidskriftsartikel (refereegranskat)abstract
- Background: Flat and depressed colorectal tumours are common in Japan but are very rare or non-existent in Western countries. Aims: To study the occurrence of flat colorectal tumours in a southern Swedish population. Methods: In this prospective study, 371 consecutive European patients were examined by high resolution video colonoscopy combined with chromoendoscopy. The nature of the lesions was determined by histopathological examination. Results: A total of 973 tumours were found; 907 (93.2%) were protruding and 66 (6.8%) were flat or depressed. Of the flat/depressed tumours, five (7.7%) were early adenocarcinomas infiltrating the submucosa. Eleven carcinomas (1.2%) were found among protruding tumours. High grade dysplasia was observed in 18% (n=11) of flat/depressed adenomas in contrast with 7.3% (n=65) of protruding adenomas, and occurred in smaller flat/depressed tumours compared with protruding ones (mean diameter 8 mm v 23 mm, respectively). Furthermore, high grade dysplasia was significantly more common in flat elevated tumours with central depression or in depressed adenomas (35.7%; 5/14) than in flat elevated adenomas (12.8%; 6/47). Conclusion: Flat and depressed tumours exist in a Western population. Future studies should address whether or not chromoendoscopy with video colonoscopy is necessary in the search for flat colorectal neoplasms.
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| 14. |
- Eriksson, Mats
(författare)
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On Weapons Plutonium in the Arctic Environment (Thule, Greenland)
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis concerns a nuclear accident that occurred in the Thule (Pituffik) area, NW Greenland in 1968, called the Thule accident. Results are based on different analytical techniques, i.e. gamma spectrometry, alpha spectrometry, ICP-MS, SEM with EDX and different sediment models, i.e. (CRS, CIC). The scope of the thesis is the study of hot particles. Studies on these have shown several interesting features, e.g. that they carry most of the activity dispersed from the accident, moreover, they have been very useful in the determination of the source term for the Thule accident debris. Paper I, is an overview of the results from the Thule-97 expedition. This paper concerns the marine environment, i.e. water, sediment and benthic animals in the Bylot Sound. The main conclusions are; that plutonium is not transported from the contaminated sediments into the surface water in this shelf sea, the debris has been efficiently buried in the sediment to great depth as a result of biological activity and transfer of plutonium to benthic biota is low. Paper II, concludes that the resuspension of accident debris on land has been limited and indications were, that americium has a faster transport mechanism from the catchment area to lakes than plutonium and radio lead. Paper III, is a method description of inventory calculation techniques in sediment with heterogeneous activity concentration, i.e. hot particles are present in the samples. It is concluded that earlier inventory estimates have been under estimated and that the new inventory is about 3.8 kg (10 TBq) of 239,240Pu. Paper IV, describes hot particle separation/identification techniques using real-time digital image systems. These techniques are much faster than conventionally used autoradiography and give the results in real time. Paper V, is a study of single isolated hot particles. The most interesting result is that the fission material in the weapons involved in the accident mostly consisted of 235U (about 4times more in mass than 239Pu). This paper concludes that there are at least two different source terms for the Thule accident debris. Another interesting feature is that it seems like uranium is leaching from the particles faster than plutonium and americium.
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| 15. |
- Gunnarsson, Mikael
(författare)
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Biokinetics and radiation dosimetry of 14C-labelled triolein, urea, glycocholic acid and xylose in man. Studies related to nuclear medicine “breath tests” using accelerator mass spectrometry
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- 14C-labelled substances have been used in biomedical research and clinical medicine for over 50 years. Physicians and scientists however, often hesitate to use these substances in patients and volunteers because the radiation dosimetry is unclear. In this work detailed long-term biokinetic and dosimetric estimation have been carried out for four clinically used 14C-breath tests: 14C-triolein (examination of fat malabsorption), urea (detection of Helicobacter pylori infection in the stomach), glycocholic acid and xylose (examination of bacterial overgrowth in the small intestine) by using the highly sensitive accelerator mass-spectrometry (AMS) technique. The AMS technique has been used to measure low 14C concentrations in small samples of exhaled air, urine, faeces and tissue samples and has improved the base for the estimation of the absorbed dose to various organs and tissues and the effective dose to man. The high sensitivity of the AMS system has also made it possible to perform 14C breath tests on patient groups which were earlier subject for restriction (e.g. small children). In summary, our results show that for adult patients - and in the case of 14C-urea breath test also for children down to 3 years of age - the dose contributions are comparatively low, both described as organ doses and as effective doses. For adults, the latter is: 14C-glycocholic acid - 0.4 mSv/MBq, 14C-triolein - 0.3 mSv/MBq, 14C-xylose - 0.1 mSv/MBq and 14C-urea - 0.04 mSv/MBq. Thus, from a radiation protection point of view there is no reason for restrictions in using any of the 14C-labelled radiopharmaceutical included in this work in the activities normally used (0.07-0.2 MBq for a 70 kg patient).
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| 16. |
- Thornberg, Charlotte
(författare)
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Irradiation of members of the general public from radioactive caesium following the Chernobyl reactor accident. Field studies in a highly contaminated area in the Bryansk region, Russia.
- 2000
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- From 1990 to 1998, estimations of the effective dose from external as well as internal irradiation from 137Cs and 134Cs were carried out for inhabitants in rural villages in the Bryansk region, Russia, highly contaminated due to the Chernobyl accident in 1986. The villages were situated about 180 km from the Chernobyl power plant and the deposition of 137Cs was in the range 0.9-2.7 MBq m-2. Yearly expeditions were conducted in autumn by members of the Departments of Radiation Physics in Malmö and Göteborg, Institute of Radiation Hygiene, St. Petersburg, and the first years also the Norwegian Radiation Protection Authority. The dose levels and their change in time were investigated for various groups of the general public. The body burden of 137,134Cs, and hence, the effective dose, was estimated from measurements of the urinary concentration of caesium radionuclides, together with direct measurements of the body content using a portable detector. The effective dose from external irradiation was estimated from measurements with thermoluminescent (TL)-dosemeters worn by the participants during one month each year. In a special case study, the changes in biokinetics of 137Cs during pregnancy was investigated in a woman with an unintended intake of 137Cs via mushrooms from a highly contaminated forest in the area. During pregnancy there is an increased excretion of caesium resulting in a biological half-time of caesium which was 54% of the half-time before pregnancy. The ratio of the 137Cs concentration in breast milk (Bq L-1) to that in the mother’s body (Bq kg-1) was 15% one month after the child was born. The body burden of 137Cs in the Russian individuals calculated from the concentration of 137Cs in urine showed a good agreement with the body burden estimated from in vivo measurements in the same individuals. Normalisation of the caesium concentration in the urine samples by the use of potassium or creatinine excretion was found to introduce systematic differences as well as a larger spread in the calculated values of the 137Cs body burden as compared with calculations without normalisation, using the urinary concentration of 137Cs only. The yearly effective dose from external and internal irradiation to inhabitants in the Russian villages varied between 1.2 and 2.5 mSv as a mean for all villages studied between 1991 and 1998 and the internal effective dose was, on average, 30-50% of the total effective dose during that period. The effective dose from external irradiation decreased on average 15% per year, while the effective dose from internal irradiation varied, depending to a great extent on dietary habits and especially the availability of mushrooms. The cumulated effective dose for a 70-year period after the accident was calculated to be around 100 mSv with the assumption that the effective dose will decrease by only the physical decay of 137Cs (2% per year) after 1998. Individuals may receive considerably higher effective doses, up to 0.5 Sv during a life-time considering the large spread in dose values among individuals.
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| 17. |
- Wallengren, Nils-Olof
(författare)
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Double-contrast MRI for the staging of rectal carcinoma: Technical aspects and clinical experience.
- 2001
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aim of the study Today´s methods for the staging of rectal carcinoma: ultrasonography with transrectal probe, CT, MRI or MRI with a rectal coil, all have limitations. The aim was therefore to develop a new, double-contrast MRI method for evaluation of rectal carcinoma. The idea was that a rectally applied contrast medium causing distension and signal void of the rectal lumen and an intravenous injection of contrast medium containing gadolinium to increase the signal from the mucosa would facilitate tumor staging and allow assessment of the rectal wall. Material, Methods and Results In a phantom study, using a 0.3T MR system, the signal alterations, artifacts and distorsion induced by the super-paramagnetic bowel contrast medium, Ferristene, were evaluated. A concentration of 20 mg iron/liter gave the best results. In a study of 12 patients, using a 0.3T MR system, the double-contrast MRI made possible the evaluation of the normal rectal wall and could be used for staging of rectal carcinoma. In a study of 29 patients, using a 0.3T MR system, the double-contrast MRI had a sensitivity of 100%, a specificity of 70% and an accuracy of 90% in distinguishing tumor stages more advanced than Dukes´ A. In a prospective, multicenter study using 1.0 or 1.5T MR systems, it was shown that the method had a sensitivity of 97%, a specificity of 50% and an accuracy of 82% for staging rectal carcinoma more advanced than stage T2. The possibility of replacing Ferristene by air in the double-contrast method was evaluated in ten patients. Ferristene was superior, mainly because the patients were unable to keep the air in the rectum. Conclusion The study has shown that double-contrast MRI is a robust and reliable method for staging of rectal carcinoma.
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| 18. |
- Dahlin, Lars, et al.
(författare)
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Granular cell tumour of the ulnar nerve in a young adult.
- 2002
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Ingår i: Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery. - : Informa UK Limited. - 1651-2073 .- 0284-4311. ; 36:1, s. 46-49
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Tidskriftsartikel (refereegranskat)
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| 19. |
- Tallini, G, et al.
(författare)
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Correlation between clinicopathological features and karyotype in 100 cartilaginous and chordoid tumours. A report from the Chromosomes and Morphology (CHAMP) Collaborative Study Group
- 2002
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Ingår i: Journal of Pathology. - : Wiley. - 0022-3417. ; 196:2, s. 194-203
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Tidskriftsartikel (refereegranskat)abstract
- The evaluation of chondroid lesions requires full integration of clinical, radiographic, and pathological data; tumour typing is often a challenge for the diagnostic pathologist. Although a variety of chromosomal abnormalities have been documented in chondroid lesions, the potential usefulness of cytogenetic analysis remains unclear. This study has critically reviewed and analysed 117 karyotyped samples from 100 patients with cartilaginous and chordoid tumours. Cases were selected based on successful chromosomal analysis and adequacy of clinical, radiographic, and pathological information. To ensure objective evaluation, the cytogenetic results were correlated in a double-blind setting with consensus diagnoses independently determined on each case, after complete review of the histological, radiographic, and clinical findings. Karyotypic aberrations were identified in 41/92 cartilaginous tumours (5/11 osteochondromas, 2/3 chondromyxoid fibromas, 0/4 chondroblastomas, 11/29 chondromas, 0/3 chondroid tumours of undetermined malignant potential, 22/40 chondrosarcomas and 1/2 miscellaneous cartilaginous lesions) and 5/8 chordomas. Complex karyotypic changes were a feature of malignant tumours (chondrosarcoma and chordoma) and of chondrosarcoma among cartilaginous tumours, where they correlated with high tumour grade. Among primary well-differentiated cartilaginous lesions of bone, the finding of an abnormal karyotype was consistently associated with a grade 1 chondrosarcoma diagnosis. Among karyotypically abnormal cartilaginous tumours, loss of distal 8q was associated with osteochondroma, +5 with synovial chondroma/chondromatosis and parosteal or soft tissue chondroma, alterations of chromosome arm 6q with chondromyxoid fibroma, +7 with bone chondrosarcoma, and 17pl alterations with grade 3 chondrosarcoma. Alterations involving 12q13 characterized synovial chondroma/chondromatosis in the chondroma group and myxoid chondrosarcoma of bone in the chondrosarcoma group. In conclusion, cytogenetic abnormalities in chondroid lesions are common and are not randomly distributed. They are associated with malignancy/tumour grade as well as with specific diagnoses in many cases, and can therefore be of potential value for tumour typing.
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| 20. |
- Björkman-Burtscher, Isabella, et al.
(författare)
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Proton MR spectroscopy and preoperative diagnostic accuracy: an evaluation of intracranial mass lesions characterized by stereotactic biopsy findings
- 2000
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Ingår i: AJNR. - 1936-959X. ; 21:1, s. 84-93
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND PURPOSE: MR imaging has made it easier to distinguish among the different types of intracranial mass lesions. Nevertheless, it is sometimes impossible to base a diagnosis solely on clinical and neuroradiologic findings, and, in these cases, biopsy must be performed. The purpose of this study was to evaluate the hypothesis that proton MR spectroscopy is able to improve preoperative diagnostic accuracy in cases of intracranial tumors and may therefore obviate stereotactic biopsy. METHODS: Twenty-six patients with intracranial tumors underwent MR imaging, proton MR spectroscopy, and stereotactic biopsy. MR spectroscopic findings were evaluated for the distribution pattern of pathologic spectra (NAA/Cho ratio < 1) across the lesion and neighboring tissue, for signal ratios in different tumor types, and for their potential to improve preoperative diagnostic accuracy. RESULTS: Gliomas and lymphomas showed pathologic spectra outside the area of contrast enhancement while four nonastrocytic circumscribed tumors (meningioma, pineocytoma, metastasis, and germinoma) showed no pathologic spectra outside the region of enhancement. No significant correlation was found between different tumor types and signal ratios. MR spectroscopy improved diagnostic accuracy by differentiating infiltrative from circumscribed tumors; however, diagnostic accuracy was not improved in terms of differentiating the types of infiltrative or circumscribed lesions. CONCLUSION: MR spectroscopy can improve diagnostic accuracy by differentiating circumscribed brain lesions from histologically infiltrating processes, which may be difficult or impossible solely on the basis of clinical or neuroradiologic findings.
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