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ResumoA Organização Mundial da Saúde (OMS) relata o câncer como uma das principais causas de morte no mundo. Uma modalidade de tratamento que vem sendo bastante utilizada no tratamento do câncer de próstata é a braquiterapia, que consiste na introdução de sementes com material radioativo no interior do orgão. Sementes de Iodo-125 podem ser inseridas soltas ou em cordas poliméricas fabricadas a partir do (poli(ácido lático-co-ácido glicólico)) (PLGA). Foi proposto neste trabalho, o estudo e desenvolvimento da metodologia de síntese do biopolímero PLGA. Os resultados obtidos demonstram que, através da metodologia utilizada, foi possível determinar os melhores parâmetros de reação (tempo e temperatura) para o PLGA na proporção 80/20 (lactídeo/glicolídeo). Com uma temperatura de 110 °C e tempo de reação 72h o rendimento da reação é superior a 90%. Os valores de massas moleculares obtidas entre os testes, ainda são baixos quando comparados com os valores obtidos por outros autores na literatura. Novos testes estão sendo conduzidos, utilizando dímeros preparados no laboratório. Testes substituindo o vácuo por uma atmosfera de nitrogênio também estão sendo realizados. Essas duas substituições podem aumentar o valor final da massa molecular do polímero. Em relação à caracterização, as técnicas utilizadas confirmaram a estrutura esperada do polímero. Palavras-chave: câncer de próstata, braquiterapia, poli(ácido lático-co-ácido glicólico), PLGA. AbstractAccording to the World Health Organization, cancer is a leading cause of death worldwide. A radiotherapy method extensively used in prostate cancer is brachytherapy, where the area requiring treatment receives radioactive seeds. Iodine-125 seeds can be inserted loose or stranded in bioabsorbable polymers produced from poly(lactic-co-glycolic acid) (PLGA). We developed the synthesis methodology for PLGA and the results obtained show that it was possible to determine the optimal reaction parameters (time and temperature) for PLGA in 80/20 (lactide/glycolide) ratio. The yield was higher than 90% using a temperature of 110 °C and reaction time of 72 hours; however, the molecular weight values obtained are very low compared to those obtained by other authors. New tests using previously synthesized dimers and nitrogen atmosphere are being performed. These conditions could potentially increase the molar mass of PLGA. All techniques used confirmed the expected structure of the polymer.

Background: The radioactive seed localization (RSL) is used in impalpable breast cancer conservative surgery to assist the surgeon in accurately locating and excising the lesion site. This study aims to present recommendations about the RSL program implementation in health institutions that perform breast cancer conservative surgery with intraoperative localization. Methods: An extensive literature review was performed. It comprehends: the committee responsible for implementation of the program actions; description of the necessary multidisciplinary team; the radiological safety committee role; the facility licensing; professionals training; material and instrumentation associated with the technique; and seed tracking system. Results: 13 topics are presented. The Program Implementation Committee must be formed by leaders from each department. The committee assumes responsibility for evaluating the necessary processes and presenting the schedule for program implementation. Since the procedure is classified as a nuclear medicine procedure it requires licensing . The Professional Team Formation, Education, and Training is a priority and simulation exercises are necessary. The Materials and Instrumentation Associated with the Technique must be well-know by the team and they should practice using radiation detectors. The seed must be always tracked, from moment they are received to discard. An Inventory for Tracking Seeds is provided. The Radiological Safety Aspects such as the ALARA principle are presented. A full description for the Radiological Procedure for Placing the seeds, the surgical removal and the Specimen Handling in Pathology focusing on how to locate the seed and retrieve them. After removed, the seeds can be placed in storage to wait for full radioactive decay or be returned to the manufacturer. Conclusions: The procedure has the advantage to increase to 2 months the time between insertion of the seed and the surgical removal. Regular multidisciplinary team meetings during program development are important to create a realistic timeline, having briefing meetings after the first 1-5 RSL cases and having annual or biannual follow-up meetings to discuss any issues or incidents. Abstract Graphic Image Created by Macrovector, obtained in Freepik at https://br.freepik.com/fotos-vetores-gratis/oncologia . Highlights This study present recommendations for RSL program implementation in hospitals Was performed by an extensive descriptive and qualitative literature review Topics 1: Implementation Committee, Professional Team Training, Instrumentation ...

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Purpose: In Brazil, cancer has become a health issue. The prostate cancer is the first larger death cause among men. The country urges to develop new treatments such as Brachytherapy. The treatment is performed only in private hospitals due to its high cost. As a Result, brazilian public hospitals do not have brachytherapy as a treatment option. Energy and Nuclear Research Institute IPEN/CNEN established a program for the production of 125Iodine seeds in Brazil. The 125Iodine seeds demand in Brazil is around 8,000 seeds per year. Methods: The 125Iodine is fixated onto the silver substrate using a new procedure (methodology is under patent process). The process lasts only 5 hours and the efficiency is up to 90%. The seeds sealing is accomplished by laser welding process resulting in a homogeneous (with only one pulse) weld without inclusions, cracks or fissures. After sealing, the weld integrity was evaluated with the use of an optical microscopy and leakage test, better than those presented in ISO 9978 standard. All of these procedures are new developed by the Brazilian researchers. Results: After almost 10 years of research and implementation IPEN laboratory is ready. The 125iodine fixation process, the laser welding and the quality control is fully automated. This process took a long time mostly because the precision required due to the seed size. With the chemical process established, the waste management is under implementation. The dosimetry method is under implementation and the final parameters are being calculated. Conclusion: The group will start the production line in 2013. With the lower cost, we hope to make the treatment more feasible to more patients.

Purpose: Brachytherapy treatment is a form of treatment in which source is in contact or placed within the patient. The iodine125 brachytherapy seeds can be used to treat prostate, brain and ophthalmic cancers. Most of the population has no access to this treatment because of its high cost ($ 60.00 each seed, 80 to 120 used for only one patient). For this reason, IPEN (Institute of Energy and Nuclear Research) develops new a seed.Methodology: Four different methods were compared: Method 1 and Method 2: Chemical deposition and eletrodeposition described in U.S. Pat. n. 4,323,055; Method 3: IPEN's new method presented in Development and production of radioactive sources used for cancer treatment in Brazil. Nukleonika, 2008; Method 4: New method developed in IPEN using oxidant agent that enforce the AgI formation. Results: Method 1: fixation efficiency 65.16%; process cost R $ 7.04Method 2: fixation efficiency 70.80%; process cost R $ 6.58 Method 3: fixation efficiency 55.80%; process cost R $ 8.24Method 4: fixation efficiency 90.11%; process Cost $ 5.00ConclusionThe fourth method achieved the efficiency, 90.11% and lowest cost $2,5. The results show that this is the best method to be implemented in IPENs new laboratory.