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Background: Prostate cancer is one of the main tumors worldwide, its treatment is multidisciplinary, includes radiotherapy in all stages: curative, radical, adjuvant, salvage and palliative. Technological advances in planning systems, image acquisition and treatment equipment have allowed the delivery of higher doses limiting toxicity in healthy tissues, distributing radiation optimally and ensuring reproducibility of conditions. Image-guided radiotherapy (IGRT) is not standard in guidelines, only recommended with heterogeneity in its own process. Materials and methods: A survey was conducted to members of the Mexican Society of Radiation Oncologists (SOMERA), to know the current status and make recommendations about its implementation and use, taking into account existing resources. Results: Responses of 541 patients were evaluated, 85% belonged to the intermediate-high risk group, 65% received adjuvant or salvage radiotherapy (RT), 80% received intensity-modulated radiation therapy (IMRT) using doses up to 80 Gy/2 Gy. Cone beam computed tomography (CBCT) was performed on 506 (93.5%), (100% IMRT) and 90% at a periodicity of 3-5/week. 3D treatment with 42% portal images 1/week. Online correction strategies (36% changes before treatment), following a diet and bladder and rectal control. Evidence and recommendations are reviewed. Conclusions: IGRT should be performed in patients with prostate cancer. In Mexico, despite limitations in the distribution of human and technological resources, it is routinely applied. More information is still needed on clinical evidence of its benefits and the process should be implemented according to infrastructure, following institutional guidelines, recommending to report the initial experience that helps to standardize national conduct.

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Growing coastal urbanization together with the intensification of maritime traffic are major processes explaining the increasing rate of biological introductions in marine environments. To investigate the link between international maritime traffic and the establishment of non-indigenous species (NIS) in coastal areas, biofouling communities in three international and three nearby local ports along 100 km of coastline in south-central Chile were compared using settlement panels and rapid assessment surveys. A larger number of NIS was observed in international ports, as expected in these 'invasion hubs'. However, despite a few environmental differences between international and local ports, the two port categories did not display significant differences regarding NIS establishment and contribution to community structure over the studied period (1.5 years). In international ports, the free space could be a limiting factor for NIS establishment. The results also suggest that local ports should be considered in NIS surveillance programs in Chile.

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BACKGROUND: Globally, cervical cancer primarily affects socially disadvantaged women. Five randomized trials were the foundation for adopting cisplatin-based chemotherapy during radiation as the standard of care for high-risk patients after primary radical hysterectomy who require adjuvant radiation and for locally advanced patients treated with definitive radiation. These results were obtained in clinical trials performed in carefully prepared academic centers; hence, we sought to determine whether these results could be reproduced when patients were treated on an out-of-protocol basis. METHODS: We reviewed the files of 294 patients with locally advanced cervical cancer who received radiation plus weekly cisplatin as routine management between 1999 to 2003, and analyzed treatment compliance, response rate, toxicity, and survival. RESULTS: A total of 294 patients who received radiation and cisplatin were analyzed. Mean age was 43.8 years (range, 26-68 years). The majority of cases were squamous cell carcinoma (87.8%), and distribution according to International Federation of Gynecology and Obstetrics (FIGO) stage was as follows: IB2-IIA, 23%; IIB, 53.3%, and IIIB, 23%; there were only two IVA cases. Overall, 96% of patients completed external beam, and intracavitary therapy. The majority of patients (67%) received the planned six courses of weekly cisplatin. Complete responses were achieved in 243 (83%) patients, whereas 51 (17%) had either persistent (32 patients, 10.8%) or progressive (19 patients, 6.4%) disease. At median follow-up (28 months; range, 2-68 months), 36 patients (12.2%) have relapsed (locally 30.5, and systemically, 69.5%). The most common toxicities were hematologic and gastrointestinal, in the majority of cases considered mild-moderate. At median follow-up (28 months; range, 2-68 months), overall and progression-free survival are 76.5 and 67%, respectively. CONCLUSION: Our results support use of chemoradiation with six weekly applications of cisplatin at 40 mg/m2 during external radiation for routine management of locally advanced cervical cancer.

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PURPOSE: Chemoradiation based on cisplatin, most commonly weekly, is the standard treatment of locally advanced cervical cancer; however, the nephrotoxic potential and the requirement for hydration of cisplatin somewhat restrains its use. The objective of this study was to determine the recommended dose of carboplatin when administered weekly during pelvic radiation (RT). METHODS AND MATERIALS: Twenty-four histologically proven, International Federation of Gynecology and Obstetrics Stage IIIB patients were treated with standard pelvic RT concurrently with six weekly applications of carboplatin at the following dose levels: 100 mg/m(2), 116 mg/m(2), 133 mg/m(2), and 150 mg/m(2). Six patients per level were treated. Acute toxicity was assessed according to the Radiation Therapy Oncology Group Acute Radiation Morbidity Scoring Criteria. The recommended dose was defined as the one that was one level below the level at which dose-limiting toxicity was present in more than one-third of patients. RESULTS: Between September 2001 and July 2002, 24 patients were accrued. All but two completed external beam radiotherapy and intracavitary treatment. The treatment was well tolerated. The median number of weekly applications of carboplatin was six, and the mean dose to points A and B was 85.6 Gy (range 75.2-91.6) and 62.9 Gy (range 58.2-74.6), respectively. RT was delivered within 41.7 days (range 33-70). Dose-limiting toxicity (leukopenia and/or neutropenia) was present in 50% of patients treated at the higher dose level (150 mg/m(2)). At the recommended dose of 133 mg/m(2), 33% of patients presented with Grade 3 leukopenia. At treatment completion, 75% of patients had a complete clinical response. CONCLUSION: Carboplatin at 133 mg/m(2), weekly for 6 weeks, is a well tolerated and effective radiosensitizer in cervical cancer patients.

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Se estudiaron la prevalencia de receptores androgénicos y de p53 en el carcinoma de próstata avanzado y las probables relaciones entre ambos y con el sistema del Gleason. El estudio se efectuó con 30 ejemplares de cáncer de próstata, 25 hormonodependientes y 5 hormorrefractarios, obtenidos de resección transuretral, biopsia transrectal y necropsias, por métodos inmunohistoquímicos y utilizando anticuerpos policlonales y monoclonales contra p53 y receptores androgénicos. Fueron positivos a p53 80 por ciento de ejemplares de tumores hormonorefractarios, contra sólo 24 por ciento de los tumores de pacientes etapa D2. La intensidad y el porcentaje de p53 en tumores refractarios y hormonodependientes fueron estadísticamente significativos (P= 0.025). Todos los ejemplares (n= 30) fueron positivos a receptores androgénicos, y las diferencias significativas fueron sorpresivamente mayores en los tumores hormonoindependientes (P= 0.009). No se encontró ninguna relación entre receptores androgénicos, clasificación de Gleason o p53, pero sí entre la clasificación de Gleason y p53, con 8 de 10 tumores positivos a p53 localizados entre 7 y 10 (pobremente diferenciados). Este estudio mostró una diferencia en el incremento de p53 en tumores metastásicos y hormonoidependientes, pero ninguna relación con el tiempo de progreso, la puntuación de Gleason o la etapa con los receptores androgénicos.

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El proyecto de grado trata de determinar si las aguas de ambalse de la represa de la Angostura pueden mediante procesos de tratamiento ser transformadas en agua potable y apta para el consumo. Deberá efectuarse el diseño hidraulico de las distintas unidades de la planta de tratamiento, este diseño considerará parametros de cálculo determinados en laboratorio segun normas internacionales para asi obtener un dimensionamiento tecnicamente adecuado a las caracteristicas del agua cruda. El aspecto estructural y las especificaciones serán determinadas por la entidad patrocinadora. El estudio se realiza bajo estos puntos: I. Introduccion. 2. Analisis de la calidad del agua. 3. Estudio de alternativas para la potabilizacion del agua. 4. Diseño de la planta de tratamiento. 5. Especificaciones tecnicas y costos. 6. Conclusiones y recomendaciones