Scientific medical journals in Mexico.

This symposium describes the main characteristics of six Mexican scientific journals indexed in Journal Citation Reports: Archives of Medical Research, Revista de Investigación Clínica-Clinical and Translational Investigation, Gaceta Médica de México, Salud Pública de México, Cirugía y Cirujanos and Salud Mental. Particular emphasis is given to their historical and organizational aspects, as well as to their main achievements recognized by the national and international scientific community.En este simposio se describen las principales características de seis revistas científicas mexicanas reconocidas por el. Journal Citation Reports: Archives of Medical Research, Revista de Investigación Clínica-Clinical and Translational Investigation, Gaceta Médica de México, Salud Pública de México, Cirugía y Cirujanos y Salud Mental. Se hace énfasis en sus aspectos históricos y organizacionales, así como en sus logros principales ante la comunidad científica nacional e internacional.

[Motivation and learning strategies in pediatric residents]. / Motivación y estrategias de aprendizaje en residentes de pediatría.

BACKGROUND: Motivation is an internal mood that moves individuals to act, points them in certain directions, and maintains them in activities, playing a very important role in self-regulated learning and academic performance. Our objective was to evaluate motivation and self-regulation of knowledge in pediatric residents in a third-level hospital, and to determine if there are differences according to the type of specialty and sociodemographic variables. MATERIAL AND METHODS: All residents who agreed to participate responded to the Motivated Strategies for Learning Questionnaire. Cronbach alpha was performed to determine reliability. The mean value of each subscale was compared with Student's t test or ANOVA, correlation of subscales with Pearson test. A value of p≤0.05 was considered significant. RESULTS: We included 118 residents. The questionnaire was highly reliable (α=0.939). There were no significant differences in motivation or learning strategies according to sex, marital status, or age. Those residents studying a second or third specialization had significantly higher scores in elaboration, critical thinking, and peer learning. There were significant correlations between intrinsic motivation and self-efficacy with the development of knowledge strategies such as elaboration, critical thinking, and metacognitive self-regulation. CONCLUSIONS: Our students present average-to-high scores of motivation and knowledge strategies, with a significant difference according to type of specialization. There is a high correlation between motivation and knowledge strategies.

Trends in Medical Specialization and Employability in Mexico According to Gender.

BACKGROUND: Feminization of medicine is a worldwide phenomenon. Countries must consider feminization of medical specializations in the planning of health public politics. OBJECTIVE: To analyze trends in medical specialization and employability in México according to gender. METHOD: We analyzed the electronic repositories of students and hired physicians at IMSS from 2006-2020. RESULTS: 42,647 specialists graduated in the period. The percentage of women increased 3% in medical specializations and 9% in surgical ones. Women significatively predominate in first entry and controllable lifestyle specialization. The percentage of hired women physicians increased 14 and 17% in leadership positions. CONCLUSIONS: There is a steady increase in feminization of medical specialization. To date, 52% of residents, 48% of hired physicians and 42% of leaders are women.

[Survival of patients with malignant astrocytomas according to the expression of Ki67 antigen in a pediatric hospital]. / Sobrevida de los pacientes con astrocitoma de alto grado que expresan el antígeno Ki67, atendidos en un hospital de pediatría.

BACKGROUND: Pediatric patients with malignant gliomas and same histological diagnosis respond distinctly to treatment. It is thus necessary to determine other factors that may influence the response to treatment and survival. Over expression of the Ki67 protein has been associated with poor treatment response. The aim of this study was to determine if the expression of this antigen influences survival of patients treated for malignant gliomas in the CMN SXXI Pediatrics Hospital. METHODS: We included patients with anaplasic astrocitoma or glioblastoma multiforme seen at our hospital between 1995 and 2005. We determined the expression of Ki67 by immunohistochemistry and correlated the findings with tumor histology and patient survival. RESULTS: Of the 21 patients studied, 12 overexpressed antigen Ki67. There was no significant association between over expression of Ki67 and survival, although we observed a clinical association. Over expression of Ki67 correlated with more aggressive histology. Being under the age of 11 was a poor prognostic factor. Overall survival was 49% at 120 months. CONCLUSIONS: Being young (under 11 years) is a marker of poor prognosis among pediatric patients with anaplasic astrocytoma or glioblastoma multiforme. Overexpression expression of antigen Ki67 is associated with histology and may be associated with poor survival among patients treated in our hospital.

[Prognostic and survival factors among pediatric patients with ependymomas]. / Factores pronósticos y sobrevida de pacientes pediátricos con ependimomas.

BACKGROUND: Ependymomas constitute the third most common intracranial tumors in children. Risk factors include age, location, extent of surgical excision, and radiation therapy. Recently, chromosomal imbalances have been described. OBJECTIVE: Determine global survival of patients with ependymomas according to different prognostic factors. METHODS: We reviewed the medical charts of every pediatric patient with ependymoma from 1996 to 2005. Genomic imbalances were determined using comparative genomic hybridization (CGH). Survival was calculated using the Kaplan and Meier method. We used the Log Rank test for each risk factor. Death risk was calculated by odds ratio (OR). RESULTS: We included 24 patients. Global survival was 58.04%. The presence of chromosomal imbalances, particularly in chromosome 21, significantly affected survival Being under 5 years of age, anaplastic histology, chemotherapy other than ICE (ifosfamida-carboplatin-etoposide) and partial resection increased the risk of death. CONCLUSIONS: Known risk factors were confirmed in our study, including chromosomal imbalances. We describe a new chromosomal imbalance in chromosome 21 among 30% of study participants.

Social Violence Increases the Risk of Suicidal Ideation Among Undergraduate Medical Students.

BACKGROUND: Depression is highly prevalent worldwide, and may have fatal consequences. Violence is associated to psychopathology and has exponentially increased in some areas of Mexico. Healthcare professionals are vulnerable to increased anxiety, depression, suicide and lately, to violence by organized crime. The aim of the study was to determine the prevalence of anxiety/depression/suicidal ideation and the weight of social violence as a risk factor. METHODS: Cross sectional study in three generations of undergraduate medical students at entry to internship year in our institution. All students voluntarily agreed to participate. All of them answered Beck and HAM-A. Two generations also responded Plutchik suicidal risk inventory. Sex, type of university and degree of violence in their geographic areas were also recorded. Prevalence rates were calculated for each outcome. χ2 tests and odds ratio (OR) for bivariate analysis, and Mantel-Hanezel to adjust according to level of violence. RESULTS: All of the eligible students responded the anxiety and inventories (n = 8,858), and 6,451 also responded the suicide risk test. Overall, 37.2% displayed severe anxiety, 14.9% moderate/severe depression and 8.5% suicidal ideation. Female sex and private university increased the risk for anxiety and depression. High violence, severe anxiety or depression increased the risk for suicidal ideation. Adjusted by violence zone, female sex, being single and the coexistence of depression were associated with a higher risk for suicidal ideation. CONCLUSIONS: Anxiety, depression and suicidal ideation are highly prevalent among premedical interns in Mexico. Living in highly violent areas significantly increases the risk for anxiety/depression/suicidal ideation.

Palonosetron hydrochloride is an effective and safe option to prevent chemotherapy-induced nausea and vomiting in children.

BACKGROUND: Emesis and nausea are common adverse effects of chemotherapy. Consequences include dehydration, acute renal failure, esophageal rupture, electrolyte imbalance and undernutrition, among others. First-generation 5-HT3 antagonists significantly reduce these symptoms but are expensive and require administration every 8-12h. Palonosetron, a second generation 5-HT3 antagonist has proven better results in adult populations. Other benefits include a one-dose administration with effect for up to 7 days and a lower treatment cost. No clinical studies have evaluated the safety and efficacy of palonosetron in children. METHODS: Prior to every course, patients were randomized to receive palonosetron or ondansetron. Patients or guardians recorded the number of emetic events and the intensity of nausea over a 7-day period. They also reported any possible adverse effects. Statistical analysis included chi(2) test, relative risk, and Student's t test. RESULTS: Fifty courses were analyzed for each group. There was a significant reduction in emesis on the first 3 days and in the intensity of nausea in the first four days in the palonosetron group. There was an increased risk of presenting emesis and nausea in the acute phase when treated with ondansetron. No adverse effects were reported. The cost of treatment was also reduced when using palonosetron. CONCLUSIONS: Palonosetron is a safe and effective antiemetic treatment in children, as well as being cost effective.

Phase II study of metronomic chemotherapy with thalidomide, carboplatin-vincristine-fluvastatin in the treatment of brain stem tumors in children.

BACKGROUND: Brain stem tumors (BST) constitute 20% of all intracranial tumors. Survival for these patients has been very poor worldwide. Four different treatment schemes have been evaluated at our institution, with only a discrete increment in survival when treated with carboplatin-vincristine and fluvastatin (CVF). Low-dose, continuous antiangiogenic treatment has been recently introduced in the treatment of cancer. Our objective was to determine tumor response to metronomic chemotherapy combined with an antiangiogenic drug and fluvastatin and to calculate the survival of pediatric patients with brain stem tumors. METHODS: This was a phase II study. A magnetic resonance (MRI) study was made at inclusion and after the fourth course. Routine laboratory analyses were performed prior to each treatment scheme. Patients received four courses of chemotherapy every 28 days consisting of thalidomide alternating with fluvastatin every 14 days and combined with carboplatin and vincristine every 14 days followed by radiotherapy (56 cGy) and four more courses of the same chemotherapy. Toxicity was evaluated according to Miller criteria. RESULTS: Nine recently diagnosed BST patients were included. Five patients had low-grade astrocytomas, three patients had glioblastoma multiforme, and one patient presented high-grade astrocytoma. There was a significant reduction in tumor volume and a significant increase in survival at 24 months. Two patients died. Toxicity included carboplatin allergy in one patient, grades 1 and 3 neutropenia in two patients, and grade 4 thrombocytopenia in two patients. CONCLUSIONS: Metronomic treatment with carboplatin and vincristine associated with fluvastatin and thalidomide significantly increased survival of pediatric brain stem tumor patients. Tumor volume showed a significant reduction. Quality of life was also increased. Sample size must be increased in order to make final conclusions.

Implementation of a Nationwide Strategy for the Prevention, Treatment, and Rehabilitation of Cardiovascular Disease "A Todo Corazón".

The cardiovascular diseases (CVDs) have a growing impact over the world mortality, affecting mostly low and middle-income countries. This is due to changes in the population pyramid and the increase in unhealthy lifestyles that predispose the global population to cardiovascular risk factors such as overweight, obesity, smoking, hypertension, diabetes, dyslipidemias and metabolic syndrome. Ischemic heart disease and the cerebral vascular event remain the first causes of death reported by the World Health Organization (WHO) for more than a decade. Mexico has high prevalence in obesity, overweight, hypertension and diabetes in the population over 20 years old; Within the OECD countries (Organization for Economic Cooperation and Development) are the country with the highest mortality due to acute myocardial infarction over 45 years in the first 30 days. In order to face the growing pandemic of CVDs, the IMSS, it has developed and implemented a comprehensive care program called "A Todo Corazon", it is the first program of integral care which seeks to strengthen the actions to improving the impact of CVDs from health. This review is focused on describing the 7 axes that make up the program; each axe is described in detail. Axes one to three are dedicated to promotion and primary prevention of CVDs. Axes 4 and 5 are dedicated to infarction code, as a national strategy to confront the principal cause of death in Mexico. Finally axes 6 and 7 are dedicated to intensive care, secondary prevention and rehabilitation of CVDs.

Clinical and molecular parameters for risk stratification in Mexican children with medulloblastoma.

BACKGROUND: Clinical, histological, and more recently, molecular factors have been described as important in survival of the patient with medulloblastoma. Best survival results include aggressive chemotherapeutic protocols. More exact risk analysis may differentiate patients who require aggressive treatments from those with low risk who may respond adequately to less aggressive protocols. METHODS: Twenty six patients were included over a 10-year period and were followed for at least 5 years. Personal variables were obtained from their clinical records. Immunochemistry studies were performed on their formalin-fixed paraffin-embedded tissues. Statistical analysis included chi(2) test, odds risk, linear regression models, and Kaplan-Meier survival analysis. RESULTS: Metastatic disease and chemotherapy with VP16-carboplatin reduce the patient's probability of survival, whereas anaplastic histology increases the probability of death. Global survival and disease-free survival were 66.6 and 45.02%, respectively. Only two patients overexpressed the ERBB2 protein, and no significant difference was found in survival in terms of ERBB2 overexpression. CONCLUSIONS: Risk stratification has become very important in medulloblastoma. We found an increased hazard of death when metastatic disease was present. Gene expression in Mexican children requires a larger sample in order to be analyzed.

[Workplace bullying during specialty training in a pediatric hospital in Mexico: a little-noticed phenomenon]. / Acoso laboral durante la formación como especialista en un hospital de pediatría en México: un fenómeno poco percibido.

BACKGROUND: Workplace bullying (WB) is a hostile or intimidating behavior that is practiced against workers and has a negative impact on health, job performance, and the learning process. The objective was to research WB magnitude and its associated factors in Mexico. METHODS: Mixed method study. A survey was designed and administered to all the residents in a pediatric hospital in Mexico who agreed to participate. The survey was divided in two sections: a) resident self-reported events of workplace bullying and associated factors, b) situations and factors of abuse were interrogated in a targeted manner. RESULTS: 137 residents participated in the survey, out of which 32% spontaneously reported have been bullied, and 82.4% harassing behaviors in the targeted section. Personal factors that cause WB in this population were: gender, mental skills and physical appearance. Situations that predispose to harassment were: hierarchy, and lack of supervision. Teachers were more frequently the perpetrators. Factors identified as significant for WB were: being female, younger than 29, studying pediatrics, being unmarried, and having reported harassment spontaneously. CONCLUSIONS: The frequency of WB and associated factors are similar to those reported by other authors. Half of the residents did not report spontaneously harassing events, but identified them in the targeted section, which suggests that they consider them as part of the "costumes and habits" during their medical training, or they consider them irrelevant.

Introducción: el acoso laboral es una conducta intimidatoria que se practica contra el trabajador e impacta negativamente en el estado de salud, el desempeño laboral y el aprendizaje. El presente trabajo investiga su magnitud y sus factores asociados en México. Métodos: metodología mixta. Se diseñó y aplicó una encuesta a los residentes de un hospital pediátrico de México que aceptaron participar. Se dividió en dos secciones: a) el residente reportó eventos de mobbing y factores asociados, b) se exploraron de manera dirigida situaciones de abuso documentadas en la literatura. Resultados: participaron 137 residentes. De ellos, 32% reportó espontáneamente haber sufrido acoso, mientras que 82.4% lo refirió en el cuestionario dirigido. Los factores personales precipitantes fueron: sexo, habilidades mentales y apariencia física. Las situaciones que predispusieron al acoso fueron jerarquía y falta de supervisión. Los profesores fueron los principales perpetradores, ocurrió más comúnmente en hospitalización. Se identificaron como factores significativos el sexo femenino, tener menos de 29 años, estudiar pediatría, ser solteros y haber reportado acoso de manera espontánea. Conclusiones: la frecuencia de acoso es similar a la reportada por otros autores. La mitad de los residentes no reportaron espontáneamente eventos de acoso pero los identificaron en el cuestionamiento dirigido, lo que sugiere que consideran estos eventos como parte de "los usos y costumbres" durante su entrenamiento médico, o los consideran irrelevantes.

[Non-satisfaction medical doctors during pediatric training. Prevalence and associated factors]. / Insatisfacción durante la residencia de pediatría. Prevalencia y factores asociados.

INTRODUCTION: The prevalence of medical discontent is approximately 4%. Factors such as gender, age, type of specialization, disillusion with the profession and economical factors have been identified among graduated medical doctors. Residents mentioned educational strategies as an additional factor of discomfort. OBJECTIVE: To identify the prevalence and factors that influence on resident's discontent during their pediatric training program. MATERIAL AND METHODS: The principal motives of dissatisfaction during the period of training in pediatric residence were identified using the semantic nets technique. RESULTS: Prevalence of dissatisfaction was 3.1%. The principal motives were: educational strategies, duration of medical career, work overload, hierarchical systems and abuse. CONCLUSIONS: Prevalence of dissatisfaction during a medical residence is similar to that reported in graduated pediatricians, and occurs during the first two years of residence. Educational strategies were one of the principal causes of discontent, and other local factors such as work overload, jeriarquical systems and abuse were identified.

[Rethinking the surgical approach to intestinal obstruction surgery in neonates. Experience of a third-level hospital]. / Abordaje quirúrgico para cirugía por obstrucción intestinal en neonatos.

BACKGROUND: Choosing laparotomy incision (transverse or midline) depends on the area that needs to be exposed, the urgency of the procedure, and the surgeon's preference. In the Hospital de Pediatría of the Centro Médico Nacional Siglo XXI of the IMSS, the traditional approach is performed by midline in these patients. Our objective was to determine if the midline approach is safe for handling neonates undergoing laparotomy for intestinal obstruction. METHODS: A retrospective study included all neonates who underwent laparotomy for intestinal obstruction by midline approach in the period from January 2010 to January 2012. RESULTS: 34 patients were studied. 88.2 % were urgency procedures; surgery time was more than 120 minutes. Surgical bleeding in all patients was less than 20 milliliters. Complications were found in 44 % of patients, of which the most frequent was infection (29 %) and wound dehiscence (20 %). As for respiratory complications, 32.4 % had atelectasis and 14.7 %, pneumonia. 14.7 % had incisional hernia at one year. CONCLUSIONS: The frequency of immediate and non-immediate post-surgical complications is higher than those reported in the literature with transverse approach. The frequency of post-incisional hernia at one year is similar to that reported with the latter approach.

Introducción: la elección de una incisión para laparotomía depende del área que necesite ser expuesta, la urgencia del procedimiento y las preferencias del cirujano. En el Hospital de Pediatría del Centro Médico Nacional Siglo XXI del IMSS, tradicionalmente se realiza abordaje por línea media en estos pacientes. Nuestro objetivo fue determinar si el abordaje por línea media es seguro para el manejo de neonatos sometidos a laparotomía por oclusión intestinal. Métodos: estudio retrospectivo que incluyó a todos los neonatos sometidos a laparotomía por oclusión intestinal mediante abordaje por línea media, en un período comprendido entre enero 2010 a enero 2012. Resultados: se estudiaron 34 pacientes. El 88.2 % de los procedimientos fueron de urgencia. Se encontraron complicaciones en 44 % de los pacientes, de las cuales la más frecuentes fueron: infección y dehiscencia de herida. Dentro de las complicaciones respiratorias, el 32.4 % presentó atelectasia y el 14.7 %, neumonía. Tuvieron hernia postincisional al año el 14.7 %. Ninguna de las variables del paciente o la cirugía fueron estadísticamente significativas para el desarrollo de complicaciones. Se presentaron más complicaciones en los procedimientos de urgencia, en pacientes menores a 2000 gramos y con tiempos quirúrgicos mayores a 120 minutos. Conclusiones: la frecuencia de complicaciones inmediatas y mediatas posteriores al evento quirúrgico son mayores a las reportadas en la literatura con abordaje transverso. La frecuencia de hernia postincisional al año es similar a lo reportado con éste último abordaje.

[Reliability and validity of an instrument to evaluate integral clinical competence in medical residents]. / Confiabilidad y validez de un instrumento de evaluación de la competencia clínica integral de médicos residentes.

BACKGROUND: The evaluation of clinical competence in medical residents is a complex procedure. Teachers need reliable and valid instruments to evaluate objectively the, clinical competence. The aim of this study was to determine the reliability and validity of an instrument designed to evaluate the clinical competence of medical residents. METHODS: We designed an instrument taking into consideration every part of the clinical method, and three different levels of competence were determined for each one. The instrument was examined with regards to the clarity, pertinence and sufficiency of each clinical indicator by five expert pediatricians. The instrument was finally constituted by 11 indicators. Each resident was evaluated independently by three pediatricians. RESULTS: A total of 651 measurements were done in 234 residents. The instrument distinguished between extreme groups, had a value of Cronbach's alpha of 0.778 and the factorial analysis set apart two factors: clinical competence and complementary competences. No statistical differences were found between evaluators neither in global evaluation or in each indicator. CONCLUSIONS: The instrument here proposed is valid and reliable. It may be used in formative evaluation of medical residents in clinical specialization programs.

Introducción: la evaluación de la competencia clínica de un residente es un proceso complejo. Los profesores requieren de instrumentos confiables y válidos para evaluar objetivamente la competencia clínica. El objetivo fue evaluar la confiabilidad y validez de un instrumento (IECC) diseñado para evaluar la competencia clínica integral de los médicos residentes. Métodos: se diseñó un instrumento a partir de los diferentes pasos del método clínico, y se determinaron tres niveles de competencia para cada uno. El instrumento fue revisado respecto a su claridad, pertinencia y la suficiencia de sus indicadores planteados por cinco médicos pediatras expertos. Cada residente fue evaluado independientemente por tres médicos. Resultados: se obtuvieron en total 651 mediciones en 234 residentes. El instrumento discriminó entre grupos extremos. Se obtuvo un valor de alfa de Cronbach de 0.778 y el análisis factorial distinguió dos factores: competencia clínica y competencias complementarias. No se encontraron diferencias entre evaluadores en las calificaciones globales ni en cada uno de los indicadores. Conclusión: el instrumento propuesto es válido y confiable. Se propone como una herramienta más en la evaluación formativa de los médicos residentes de especialidades clínicas.

[Pineal region tumors in children: is gross-total resection necessary? A single-center experience]. / Tumores de región pineal en niños: ¿es la resección total necesaria? Experiencia en un centro de referencia.

BACKGROUND: Survival of children with pineal region tumors has increased significantly in the last decade; these tumors have an insidious outcome associated with endocrine disorders with high morbidity and mortality, especially after gross resection. The objective was to report the survival, outcome, morbidity and mortality according to type of surgery, histology and treatment in children with pineal region tumors. METHODS: This retrospective study included all patients of 17 years or less with diagnosis of pineal region tumor, who went over a period of 10 years to a children's hospital. A histopathological review was made, and the extent of resection was determined. The survival was also estimated. RESULTS: Forty-six patients were included, out of which 36 had complete medical records and adequate pathologic material. Gross resection was performed in 24 (66.6 %), and biopsy in 12 (33.3 %); 23 (88 %) patients died; hydroelectrolytic imbalance was the cause of 14 deaths (60 %) and the other nine (39.1 %) were secondary to tumor progression. Ten-years survivals among patients treated with gross resection and biopsy were 52 and 75 %, respectively (p = 0.7). Endocrine alterations were observed in 13 patients (36.1 %); in 10 of these (76.9 %) the total resection was performed. CONCLUSIONS: Pineal region tumors in children can be treated with diagnostic biopsy, followed by adjuvant treatment consisting of chemotherapy and radiotherapy.

Introducción: la supervivencia de los niños con tumores de la región pineal se ha incrementado en la última década; estos tienen una evolución insidiosa asociada con los desórdenes endocrinológicos y una alta morbilidad y mortalidad, sobre todo después de la resección. El objetivo es reportar la supervivencia, la morbilidad y mortalidad según el tipo de cirugía, la histología y el tratamiento en un grupo de niños con tumores de la región pineal. Métodos: estudio retrospectivo que incluyó a todos los pacientes con diagnóstico de tumor de la región pineal menores de 17 años de edad que acudieron en un periodo de 10 años a un hospital de pediatría. Se realizó una revisión histopatológica, se determinó la extensión de la resección y se estimó la supervivencia. Resultados: se incluyeron 46 pacientes, 36 de los cuales tenían expediente completo y material de patología adecuado. La resección total se realizó en 24 (66.6 %) y biopsia en 12 (33.3 %); fallecieron 23 pacientes (88 %) y fue el desequilibrio hidroelectrolítico la causa de 14 defunciones (60 %) y la progresión tumoral la causa de las 9 defunciones restantes (39.1 %). La sobrevida a 10 años de los pacientes tratados con resección total y biopsia fue del 52 y 75 %, respectivamente, con una p = 0.7; se presentaron alteraciones endocrinológicas en 13 (36.1%) pacientes de los cuales a 10 (76.9 %) se les realizó la resección de la tumoración. Conclusión: los tumores de la región pineal en niños se pueden tratar con biopsia diagnóstica seguida de tratamiento adyuvante con quimioterapia y radioterapia.

Las revistas científicas médicas en México / Scientific medical journals in Mexico

Resumen En este simposio se describen las principales características de seis revistas científicas mexicanas reconocidas por el Journal Citation Reports: Archives of Medical Research, Revista de Investigación Clínica-Clinical and Translational Investigation, Gaceta Médica de México, Salud Pública de México, Cirugía y Cirujanos y Salud Mental. Se hace énfasis en sus aspectos históricos y organizacionales, así como en sus logros principales ante la comunidad científica nacional e internacional.

Abstract This symposium describes the main characteristics of six Mexican scientific journals indexed in the Journal Citation Reports: Archives of Medical Research, Revista de Investigación Clínica-Clinical and Translational Investigation, Gaceta Médica de México, Salud Pública de México, Cirugía y Cirujanos and Salud Mental. Particular emphasis is given to their historical and organizational aspects, as on well as their main achievements recognized by the national and international scientific community.

[Neuroblastoma: prognostic factors and survival. Experience in Hospital de Pediatria del Centro Medico Nacional del Siglo XXI and review of the literature]. / Neuroblastoma: factores pronósticos y sobrevida. Experiencia en el Hospital de Pediatría del Centro Médico Nacional Siglo XXI y revisión de la literatura.

Neuroblastoma (NB) is the most frequent extracranial solid tumor in children according to the literature. In Mexico it is less frequent, fallen to 8th place. Our objective was to analyze our experience and compare it with the one reported in other countries. We included all patients admitted to our hospital during the previous five years and who had not received any treatment. Patients with stages I, II, and IV received cyclophosphamide and epirrubicin. Patients with stages were III and IV received the same chemotherapy alternating with cisplatinum., ifosfamide and etoposide during 12 months as well as massive doses of 131-MIBG and surgical ablation of the remaining tumor when possible. We included 30 patients, 25 with initial presentation in the abdomen. Five were in early stages and 20 (70%) were advanced with an overall survival of 100% and 27% at 5 years respectively. When analyzed by age, 40% were 12 months of age and 60% older, with survival of 100% and 27% in the same period, respectively. According to histology there was 91% survival for differentiated and 23% for undifferentiated tumors. The chemotherapeutic regimen reported is effective but not better than that reported by other authors, in which some benefits are seen with use of transplant and immunotherapy. The most important prognostic factors are still considered to be age, stage and histology.