13 research outputs found
Simultaneous breast cancer and DLBCL lymphoma — role of PET/CT examination with 18F-FDG and 18F-FES
Breast cancer is the most common cancer in women in the western world.
The estrogen receptor (ER) is expressed in two thirds of newly diagnosed breast cancers, so hormonal treatment is performed only in the receptor positive patients. The most successful ER imaging radiopharmaceutical in PET techniques is 16α-[18F]-flouro-17β-estradiol (18F-FES).
The diffuse large B cell lymphoma (DLBCL) is one of the most common NHL, however, non-Hodgkin lymphoma constitutes only 4% of all primary cancers in women. The typical staging of disease is done using 18-fluorodeoksyglukose (18F-FDG) PET/CT
Bone metastases diagnosis possibilities in studies with the use of 18F-NaF and 18F-FDG
Scintigraphy of the skeletal system is performed mainly with
the use of 99mTc-MDP. There are other radiopharmaceuticals
showing affinity to bone lesions: 99mTc-MIBG, 201Tl, 131I (in the
case of papillary or follicular thyroid cancers), and 99mTc (V)
DMSA (in the case of medullary cancer). Currently, positron
emitted radioisotopes are also used in clinical practice. It seems
that 18F-NaF/PET is a highly sensitive and specific modality for
detection of metastases and other bone lesions. Certain data
concerning the role of 18F-FDG, 18F-choline, or 68Ga-DOTATATE
can be found. The aim of this article is to review the role of
18F-NaF and 18F-FDG in diagnosis of bone metastases.
Nuclear Med Rev 2011; 14, 2: 105–10
Radiotherapy treatment planning for breast cancer patients after a subcutaneous mastectomy with the use of a prosthesis or expander
Introduction. Medical physicists planning radiation treatment are increasingly confronted with situations that require special attention. Undoubtedly, one such situation is the postoperative irradiation of a patient with breast cancer in which there is a prosthesis or an expander. In recent years, expanders have appeared in this location, which, due to the density of the device’s valve makes it difficult to prepare an acceptable treatment plan. The study aims to present treatment planning in these situation in various Polish cancer centres and to compare overall patient preparation for the treatment.
Material and methods. A questionnaire was prepared and sent to more than 20 radiotherapy departments, which included basic questions regarding the preparation of an irradiation plan for patients treated for breast cancer after a subcutaneous mastectomy with immediate reconstruction with a prosthesis or expander. The survey encompassed eight radiotherapy departments.
Results. Not all radiotherapy departments require a manufacturer’s certificate, which shows that the manufacturer does not prohibit the use of a prosthesis/expander during treatment with ionizing radiation. The X 6MV photons and the supine position, total and fraction doses: from 40 to 60 Gy and from 2 to 2.67 Gy, respectively, are the most commonly used. The way of defining them also depends on the oncological centre. The most commonly used irradiation technique is VMAT.
Conclusion. The conclusion from the questionnaire – no standardisation of treatment planning – should encourage the community, at least medical physicists, to develop rules of conduct in this case. Irradiation techniques are mainly dynamic ones. The expander or prosthesis does not significantly affect the dose distributions
Virtual radiotherapy – a new tool in education process of medical physicists
Fizyk medyczny to zawód, który wymaga umiejętności zastosowania metod fizyki w medycynie. Jeżeli dziedziną medycyny jest radioterapia, wówczas należy nauczyć się wykorzystania metod pomiarowych promieniowania jonizującego (dozymetria kliniczna) oraz informatyki (systemy planowania leczenia) w praktyce klinicznej. W procesie dydaktycznym wymagane jest wykorzystanie sprzętu medycznego, który jest w codziennym użytku. Pojawia się konflikt (pozorny), czy aparatura medyczna ma być wykorzystywana do celów edukacyjnych, czy też leczenia chorych. W okresie, kiedy informatyka i związana z nią technologia bardzo dynamicznie się rozwijają, kwestią czasu było pojawienie się wirtualnych akceleratorów, symulatorów. Rozwiązanie to bardzo ułatwia, z punktu widzenia organizacji pracy, proces szkolenia nie tylko fizyków medycznych, ale również lekarzy oraz elektroradiologów obsługujących aparaty terapeutyczne w radioterapii.Medical physicist is a profession that requires the ability to apply physics methods in medicine. If the field of medicine is radiotherapy, then you should learn how to use radiation measurement methods (clinical dosimetry) and computer science (treatment planning systems) in clinical practice. The teaching process requires the use of medical equipment that is in use daily. There is a conflict (an apparent one) whether medical equipment is to be used for educational purposes or for treating patients. In the period when IT and related technology is developing very dynamically, it was just the matter of time when virtual accelerators, simulators appear. In such virtual reality we can use these programs to move virtual accelerator’s gantry, collimator... This solution greatly facilitates, from the point of view of work organization, the training process not only of medical physicists, but also doctors and technicians in radiotherapy
Micronuclei in human peripheral blood lymphocytes exposed to mixed beams of X-rays and alpha particles
Purpose. To study the cytogenetic effect of exposing human peripheral blood lymphocytes (PBL) to a mixed beam of alpha particles and X-rays.
Methods. Whole blood collected from one donor was exposed to different doses of alpha particles (241Am), X-rays and a combination of both. All exposures were carried out at 37 °C. 3 independent experiments were performed. Micronuclei in binucleated PBL were
scored as the endpoint. Moreover, the size of micronuclei was measured.
Results. Exposure of PBL to a mixed beam of high and low LET radiation led to significantly higher than expected frequencies of MN. The size measurement of MN did not reveal any differences between the effect of alpha particles and mixed beam.
Conclusions. Combined exposure of PBL to alpha particles and X-rays leads to a synergistic effect as measured by the frequency of MN. From the analysis of MN distributions we conclude that the increase was due to an impaired repair of X-ray induced DNA damage.JRC.F.4-Nuclear Reactor Integrity Assessment and Knowledge Managemen
Characterisation of a Setup for Mixed Beam Exposures of Cells to 241Am Alpha Particles and X-Rays
Exposure of humans to mixed fields of high and low linear energy transfer (LET) radiation occurs in many situations, for example in urban areas with high levels of indoor radon as well as background gamma radiation, during airplane flights or certain forms of radiation therapy. From the perspective of health risk associated with exposure to mixed fields it is important to understand the interactions between the different radiation types. In most cellular investigations on mixed beams the two types of irradiations have been applied sequentially. Simultaneous irradiation is the desirable scenario but requires a dedicated irradiation facility. We have constructed such a facility where cells can be simultaneously exposed to 241 Am alpha particles and 190 kV X-rays at 37oC. In this technical report we present the technical details and the dosimetry of the setup, as well as validating the performance of the setup for clonogenic survival in AA8 Chinese hamster ovary cells. No significant synergistic effect was observed. The relative biological effectiveness (RBE) of the alpha particles was 2.56 for 37% and 1.90 for 10% clonogenic survival.JRC.F.4-Nuclear Reactor Integrity Assessment and Knowledge Managemen
The Yield of Radiation-Induced Micronuclei in Early and Late-Arising Binucleated Cells Depends on Radiation Quality
There are conflicting data regarding the effect of culturing time of human peripheral blood lymphocytes on the yield of chromosomal aberrations induced by sparsely ionising radiation in the G0 phase of the cell cycle. While some authors find that the yield of aberratioons does not change with time, others find increased frequencies of aberrations with harvesting time. The reasons for the conflicting results are not known, but the majority of studies were performed with lymphocytes of a single donor collected at one time point. We performed a study to verify if individual variability could be confounding factor. As a positive control, lymphocytes were also exposed to high LET radiation, where an efect of harvesting time on the level of damage is expected to be seen.
Blood was drawn from a total of 8 donors at two time points and exposed to X-rays, 6 MeV neutrons or alpha particles generated by an Am-241 source. Whole blood cultures were set up and micronuclei were scored in binucleated cells harvested after 72, 96 and 120 h of culture time. The results show that in lymphocytes exposed to X-rays, the frequency of Mn was generally not influenced by the culture time while for both neutrons and alpha particles consistently increased micronucleus frequencies with culture time were detected. Some individual variability was detected and the conflicting results regarding the relationship between the yield of cytogenetic damage and lymphocyte culture time can, at least partly, be due to this variabilityJRC.F.4-Nuclear Reactor Integrity Assessment and Knowledge Managemen
Investigation of the bystander effect in CHO-K1 cells
AimInvestigation of the bystander effect in Chinese Hamster Ovary cells (CHO-K1) co-cultured with cells irradiated in the dose range of 0.1–4[[ce:hsp sp="0.25"/]]Gy of high LET 12C ions and X-rays.BackgroundThe radiobiological effects of charged heavy particles on a cellular or molecular level are of fundamental importance in the field of biomedical applications, especially in hadron therapy and space radiation biology.Materials and methodsA heavy ion 12C beam from the Heavy Ion Laboratory of the University of Warsaw (HIL) was used to irradiate CHO-K1 cells. Cells were seeded in Petri dishes specially designed for irradiation purposes. Immediately after irradiation, cells were transferred into transwell culture insert dishes to enable co-culture of irradiated and non-irradiated cells. Cells from the membrane and well shared the medium but could not touch each other. To study bystander effects, a clonogenic survival assay was performed.ResultsThe survival fraction of cells co-cultured with cells irradiated with 12C ions and X-rays was not reduced.ConclusionsThe bystander effect was not observed in these studies