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Purpose: Technological advancement in the treatment of cancer together with early detection and diagnosis have considerably improved the survival of breast cancer patients. On the other hand, the potential of patients developing side effects from cancer treatment are not negligible. Despite the progress that has been made in terms of early diagnosis, therapy, and survival, including improvements in the chemotherapeutic agents, radiation and molecular targeted therapies, cardiotoxicity of cancer therapy is still cause for concern. Radiation therapy for breast cancer is associated with increased risk of heart disease and myocardial infarction. Furthermore, the association of radiation therapy to chemotherapy is an important aspect to be considered in the development of cardiac disease, as this could play an additional role as a risk factor. Besides the heart effect, other side effects can be observed in the bone, ovary, uteri, and other organs. This paper aims to review the recent literature to present the current understanding of side effects associated with breast cancer treatment. The focus is on recent preclinical studies that have assessed potential changes in different organs that may be injured after breast cancer treatment, both due to both radiation and chemotherapy agents.Conclusion: Radiation-induced heart disease is one important side effect that must be considered during the treatment planning and patient follow-up. The cardiac damage can be potentialized when chemotherapy is associated to radiotherapy, and the literature findings indicate that heart fibrosis plays an important role at the radio-chemotherapy induced cardiac damage. Literature findings also showed important side effects at the bone, that can lead to ospeoporosis, due to the decrease of calcium, after radio or chemotherapy treatments. This decrease could be explained by the ovarian failure observed at rats after chemotherapy treatment. It is of great importance to acknowledge the complications originating from the treatment, so that new strategies can be developed. In this way, it will be possible to minimize side effects and improve the patients' quality of life.
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Neoplasias da Mama/terapia , Animais , Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapiaRESUMO
PURPOSE: The Fricke dosimeter has been shown to be a viable option as an absorbed dose standard. This work aims to provide the dose distribution in an irradiator container during blood irradiation using Fricke dosimetry. METHODS: Measurements were performed using a Gammacell Elan 3000 blood irradiator at Hemocenter in Rio de Janeiro, Brazil. A specific phantom was constructed and patented by the authors to perform these measurements. Fricke solution was prepared according to international protocols, and polyethylene bags filled with Fricke solution (n = 19) were spatially distributed within the phantom. Control bags were also submitted to the same process, except the irradiation. The irradiation time was calculated to give 25.7 Gy to the central portion of the phantom, the same dose used for blood bags. RESULTS: Encouraging results were obtained with an overall uncertainty of 2.1% (k = 1). The obtained results were compared with the doses calculated by the physicist from Hemocenter based on parameters provided by the manufacturer. The mean dose delivered to the Fricke bag in the center of the phantom (cavity 2) was 28.7 ± 0.5 Gy, which is 12% higher than the planned dose of 25.7 Gy. CONCLUSIONS: The obtained results showed that the setup (Fricke and phantom) is able to perform dosimetry for blood irradiators. The delivered dose was higher than expected. This highlights the importance in controlling all the parameters during irradiation to ensure the correct dose for all irradiated bags.
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Dosímetros de Radiação , Radiometria , Brasil , Imagens de FantasmasRESUMO
PURPOSE: For x-ray beams in the low and medium energy range, reference dosimetry is established in terms of air kerma. Fricke dosimetry has shown great potential in the absolute measurements of the absorbed dose to water for high-energy ranges. Therefore, the main purpose of this work was to compare the absorbed dose to water for medium-energy x-ray beams obtained through Fricke dosimetry with that obtained from the air kerma rate. METHODS: To determine the absorbed dose to water using Fricke dosimetry, the polyethylene bags methodology was chosen. Fricke solution was irradiated at four different beam qualities. The absorbed dose to water values obtained using Fricke dosimetry were compared to those obtained using the standard protocol, using the Z-score. RESULTS: Values of the Z-score were <2 for all measurements of absorbed dose to water, which means that the values obtained using Fricke dosimetry are equivalent to those obtained using the reference protocol. The combined standard uncertainty for the absorbed dose to water obtained by Fricke dosimetry was lower than that obtained with the ionization chamber. CONCLUSIONS: Chemical dosimetry using a standard FeSO4 solution has been demonstrated to be a potential option as a standard for the quantity absorbed dose to water for medium kV x-ray qualities.
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Radiometria , Água , Calibragem , Radiografia , Raios XRESUMO
PURPOSE: To determine the effects of different polychemotherapy drugs on cortical bone structure, the femur diaphysis of rats were treated with two different chemotherapy drugs, AC (doxorubicin + cyclophosphamide) and TC (docetaxel + cyclophosphamide), and evaluated by 3D morphological analysis using synchrotron radiation microtomography. MATERIALS AND METHODS: Wistar rats were classified into three groups. One group received doses of docetaxel and cyclophosphamide (G1) - TC regimen; a second group received doses of doxorubicin and cyclophosphamide (G2) - AC regimen; while a control group (G0) received no further treatment. 3D tomographic images of the rats' femurs were obtained at the SYRMEP (Synchrotron Radiation for Medical Physics) beamline at the ELETTRA Synchrotron Laboratory in Trieste, Italy, using monochromatic X-rays with resolution of 9 µm. RESULTS: It could be shown that the treatment caused significant differences in morphological parameters measured from the 3D images of femur diaphysis of rats, among the studied groups, complementing a previous study using stereological methods, biochemistry and electron microscopy. CONCLUSIONS: Our results indicate that the same process of osteoporosis caused by advancing age might occur in young women treated with docetaxel + cyclophosphamide (TC) and doxorubicin + cyclophosphamide (AC). 3D microtomography was shown to be an outstanding technique for bone analysis.