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AIM: Describe the anatomical changes and tumor displacement due to a rapid response of a patient's small cell lung cancer (SCLC) during definitive chemoradiotherapy (CRT). BACKGROUND: The treatment for SCLC is based on CRT. If interfractional changes during RT are incorrectly assessed they might compromise adequate coverage of the tumor or increase dose to organs at risk. Image guided RT with cone-beam computed tomography (CBCT) allows to identify daily treatment variations. MATERIAL AND METHODS: Describe a SCLC case with rapid changes in size, shape and location of the primary tumor during RT. CASE REPORT: A 62-year-old woman was diagnosed with SCLC with complete obstruction of the anterior and lingular bronchi and incomplete left thorax expansion due to a 12 × 15 cm mass. During CRT (45 Gy in 1.5 Gy per fraction, twice daily) the patient presented rapid tumor response, leading to resolution of bronchi obstruction and hemithorax expansion. Tumor shifted up to 4 cm from its original position. The identification of variations led to two new simulations and planning in a 3-week treatment course. CONCLUSIONS: The complete radiological response was possible due to systematic monitoring of the tumor during CRT. We recommend frequent on-site image verification. Daily CBCT should be considered with pretreatment tumor obstruction, pleural effusion, atelectasis, large volumes or radiosensitive histology that might resolve early and rapidly and could lead to a miss of the tumor or increased toxicity. Further research should be made in replanning effect in coverage of microscopic disease since it increases uncertainty in this scenario.
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AIM: Describe the results of the first national census of radiotherapy in Mexico in order to make a situational diagnosis of radiotherapy availability, offer more accurate information to radiation oncologists, and promote an adequate scientific based investment for the country. BACKGROUND: According to the Organisation for Economic Co-operation and Development (OECD), the density of radiotherapy (RT) machines per million habitants in Mexico is approximately 1.7-1.8. Other international organizations such as DIRAC-IAEA report 1.15 per million habitants. National organizations collect data indirectly and previous surveys had a low accrual rate (32.5%). Therefore, a precise census is required. MATERIAL AND METHODS: The Mexican Radiation Oncology Certification Board (CMRO for its acronym in Spanish) conducted a nationwide census from January through November 2019. Gathered information was combined with CMRO database for sociodemographic information and human resources. RESULTS: The study included 103 RT centers [95.1% answered the survey], with a median of 2 centers by state (ranging from 0 in Tlaxcala to 20 in Mexico City) and with a report of only 1 center in 11 states (34.4%). Fifty-six (54.3%) of the centers are public. Fourteen centers (13.6%) have residency-training programs. The total number of RT machines is 162 [141 clinical and linear accelerators (87%) and 21 radionuclide units (13%)] with a median of 3 machines by state (0 in Tlaxcala to 46 in Mexico City) and with ≤3 machines in 18 states (56.25%). The overall calculated density of RT machines per million habitants is 1.32, varying from 0 in Tlaxcala to 5.16 in Mexico City. The density of linear and clinical accelerators per million population is 1.19. The total number of brachytherapy units is 66, with a median of 1 center with brachytherapy unit per state and 29 states with ≤3 centers with a brachytherapy unit (90.6%). Thirty-seven brachytherapy units (56.1%) have automated afterload high-dose rate. The overall rate of brachytherapy units per million inhabitants is 0.55, varying from 0 in 5 states (15.6%), 0.1-0.49 in 8 states (25%), 0.5-0.99 in 13 states (40.6%), 1-1.49 in 5 states (15.6%) and 1.5-1.99 in Mexico City (3.1%). The Mexican CMRO has 368 radiation oncologists certified (99 women and 269 men), of whom only 346 remain as an active part of Mexico's workforce. CONCLUSIONS: This is the first time the CMRO conducts a national census for a radiotherapy diagnostic situation in Mexico. The country currently holds a density of clinical and linear accelerators of 1.19 per million habitants. Brachytherapy density is 0.55 devices per million habitants, and 57% of radiotherapy centers have brachytherapy units.
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OBJECTIVE: Lung cancer is one the leading causes of mortality worldwide. Symptomatic manifestations of the disease generally occur in the advanced-stage setting, and therefore an important number of patients have advanced or metastatic disease by the time they are diagnosed. This situation contributes to a poor prognosis in the treatment of lung cancer. Evidencebased clinical recommendations are of great value to support decision-making for daily practice, and thus improving health care quality and patient outcomes. MATERIALS AND METHODS: This document was an initiative of the Mexican Society of Oncology (SMEO) in collaboration with Mexican Center of Clinical Excellence (Cenetec) according to Interna- tional Standards. Such standards included those described by the IOM, NICE, SIGN and GI-N. An interdisciplinary Guideline Development Group (GDG) was put together which included medical oncologists, surgical oncologistsc, radiation therapists, and methodologists with expertise in critical appraisal, sys- tematic reviews and clinical practice guidelines development. RESULTS: 62 clinical questions were agreed among members of the GDG. With the evidence identified from systematic reviews, the GDG developed clinical recommendations using a Modified Delphi Panel technique. Patients' representatives validated them. CONCLUSIONS: These Clinical Practice Guideline aims to support the shared decision-making process for patients with different stages of non-small cell lung cancer. Our goal is to improve health-care quality on these patients.
OBJETIVO: El cáncer de pulmón es una de las principales causas de mortalidad alrededor del mundo. Su historia natural, con la manifestación de síntomas en etapas avanzadas y el retraso en su diagnóstico hacen que una gran proporción de pacientes se diagnostiquen en estadios tardíos de la enfermedad, lo que hace muy complicado el tratamiento exitoso de la misma. De esto deriva la importancia de dar origen a recomendaciones basadas en evidencia para soportar la toma de decisiones clínicas por parte de los grupos interdisicplinarios que se encargan del manejo de este padecimiento. MATERIAL Y MÉTODOS: Este documento se desarrolló por parte de la Sociedad Mexicana de Oncología en colaboración con el Centro Nacional de Excelencia Tec- nológica de México (Cenetec) a través de la dirección de integración de Guías de Práctica Clínica en cumplimiento a estándares internacionales como los descritos por el Ins- tituto de Medicina de EUA (IOM, por sus siglas en inglés), el Instituto de Excelencia Clínica de Gran Bretaña (NICE, por sus siglas en inglés), la Red Colegiada para el Desarrollo de Guías de Escocia (SIGN, por sus siglas en inglés), la Red Internacional de Guías (G-I-N, por sus siglas en inglés); entre otros. Se integró en representación de la Sociedad Mexicana de Oncología un Grupo de Desarrollo de la Guía (GDG) de manera interdisciplinaria, considerando oncólogos médicos, cirujanos oncólogos, cirujanos de tórax, radio-oncólogos, y metodólogos con experiencia en revisiones sistemáticas de la literatura y guías de práctica clínica. RESULTADOS: Se consensuaron 62 preguntas cllínicas que abarcaron lo establecido previamente por el GDG en el documento de alcances de la Guía. Se identificó la evidencia científica que responde a cada una de estas preguntas clínicas y se evaluó críticamente la misma, antes de ser incorporada en el cuerpo de evidencia de la Guía. El GDG acordó mediante la técnica de consenso formal de expertos Panel Delphi la redacción final de las recomendaciones clínicas. C. CONCLUSIONES: Esta Guía de Práctica Clínica pretende proveer recomendaciones clínicas para el manejo de los distintos estadios de la enfermedad y que asistan en el proceso de toma de decisiones compartida. El GDG espera que esta guía contribuya a mejorar la calidad de la atención clínica en las pacientes con cáncer de pulmón de células no pequeñas.