Neurosurgical Residency Training in Latin America: Current Status, Challenges, and Future Opportunities.

BACKGROUND: This analysis provides an overview of neurosurgery residency programs in Latin America; it evaluates strengths, weaknesses, and limitations within the Latin American Federation for Societies in Neurosurgery countries. Considering the shared cultural background between these neighboring countries and globalization of neurosurgical education, similarities in training characteristics and equal opportunities are expected. However, program differences are inevitable and should be investigated to promote collaboration and homogenization of training. METHODS: A 39-item survey was distributed to 970 neurosurgeons and residents in Latin America to assess aspects including working conditions, teaching, research, training, educational opportunities, and socioeconomics. RESULTS: In total, 276 neurosurgeons (28%) from 16 countries completed the survey. The average participant's age was 37 ± 7 years, and the average duration of residency programs was 5 ± 1 years. Trainees participated in around 5-10 cases during the typical 80-100 work hour week. Only 5% of survey respondents had a day off after a night shift, and 60% worked at least 3 night shifts per week. Only 34% had a mentorship program, Morbidity and mortality conferences were reported by 57% and research activities were compulsory in 45%. Satisfaction with evaluation methods was reported in 29%, although 96% reported satisfaction with their training programs overall. CONCLUSIONS: This study is the first of its kind to review neurosurgical training in Latin America's. Suggested areas of improvement include regulation of working hours, implementation of mentorship programs and standardized examinations, protected research time, increased support for conferences, and more opportunities for exchange rotations that will potentially bolster collaboration between programs.

Adrenocortical carcinoma, an unusual cause of secondary hypertension.

We present the case of a female patient aged 39 years who was admitted to our hospital due to hypertension, severe hypokalaemia and metabolic alkalosis; physical examination was remarkable for plethoric moon face, centripetal obesity and bilateral lower extremity oedema. She was admitted for intravenous potassium replacement and further assessment of hypertension and associated clinical findings. Laboratory testing showed increased levels of aldosterone, renin, cortisol, testosterone and androstenedione. An abdominal CT revealed a large mass in the right adrenal gland with hepatic involvement. The patient was started on antihypertensive medications and underwent laparoscopic surgery for mass and liver biopsy. The pathological diagnosis was adrenocortical carcinoma with liver metastasis. Hyperaldosteronism is a cause of secondary hypertension and its diagnosis is usually benign. Adrenocortical carcinoma is a rare condition and aldosterone secreting tumours are even rarer; associated hypertension usually improves after tumour resection, but with the presence of metastasis, blood pressure control is difficult.

Collagen Type XI Alpha 1 Expression in Intraductal Papillomas Predicts Malignant Recurrence.

Despite the progress achieved in the treatment of breast cancer, there are still many unsolved clinical issues, being the diagnosis, prognosis, and treatment of papillary diseases, one of the highest challenges. Because of its unpredictable clinical behavior, treatment of intraductal papilloma has generated a great controversy. Even though considered as a benign lesion, it presents high rate of malignant recurrence. This is the reason why there are clinicians supporting a complete excision of the lesion, while others support an only expectant follow-up. Previous results of our group suggested that procollagen 11 alpha 1 (pro-COL11A1) expression correlates with infiltrating phenotype in breast lesions. We analyzed the correlation between expression of pro-COL11A1 in intraductal papilloma and their risk of malignant recurrence. Immunohistochemistry of pro-COL11A1 was performed in 62 samples of intraductal papilloma. Ten out 11 cases relapsed as carcinoma presents positive staining for COL11A1, while just 17 out of 51 cases with benign behaviour present immunostaining. There were significant differences (P < 0.0001) when comparing patients with malignant recurrence versus nonmalignant relapse patients. These data suggest that pro-COL11A1 expression is a highly sensitive biomarker to predict malignant relapse of intraductal papilloma and it can be used as indicative factor for prevention programs.

Collagen, type XI, alpha 1: an accurate marker for differential diagnosis of breast carcinoma invasiveness in core needle biopsies.

Accurate diagnosis of invasive breast lesions, when analyzed by Core Needle Biopsy, may suppose a major challenge for the pathologist. Various markers of invasiveness such as laminin, S-100 protein, P63 or calponin have been described; however, none of them is completely reliable. The use of a specific marker of the infiltrating tumor microenvironment seems vital to support the diagnosis of invasive against in situ lesions. At this point, Collagen, type XI, alpha 1 (COL11A1), might be helpful since it has been described to be associated to cancer associated fibroblasts in other tumors such as lung, pancreas or colorectal. This paper aims to analyze the role of COL11A1 as a marker of invasiveness in breast tumor lesions. Two hundred and one breast Core Needle Biopsy samples were analyzed by immunohistochemistry against pro-COL11A1. The results show a significant difference (p < 0.0001) when comparing the expression in infiltrative tumors (93%) versus immunostaining of non-invasive lesions (4%). Forty cases of underestimated DCIS were also stained for COL11A1, presenting a sensitivity of 90% when compared with p63 and calponin which not tagged invasion. In conclusion, pro-COL11A1 expression is a promising marker of invasive breast lesions, and may be included in immunohistochemical panels aiming at identifying infiltration in problematic breast lesions.

Clinical and radiological features of breast tumors according to history of false-positive results in mammography screening.

BACKGROUND: Women with a false-positive result after a screening mammogram have an increased risk of cancer detection in subsequent participations, especially after assessments involving cytology or biopsy. We aimed to compare women's personal characteristics, tumoral features and the radiological appearance of cancers with and without a previous false-positive result generated by additional imaging or invasive procedures. METHODS: From 1996 to 2007, 111,098 women aged 45-69 years participated in four population-based breast cancer screening programs in Spain, and 1281 cancers were detected. We included all cancers detected in subsequent screenings (n=703) and explored the occurrence of previous false-positive results. We identified false-positives requiring additional imaging or invasive procedures. Differences on tumoral features (invasiveness, tumor size, and lymph node status) and radiological appearance were assessed by Chi-square test, and agreement between the location of cancer and prior suspicious by Cohen's kappa coefficient. A multivariate analysis was preformed to evaluate the effect of previous screening results and age on the odds of presenting an in situ carcinoma. RESULTS: Among the 703 cancers detected in subsequent screenings, 148 women (21.1%) had a previous false-positive result. Of these, 105 were by additional imaging and 43 by invasive procedures. Women with prior false-positive result requiring invasive assessment, compared to women with negative tests, and women with prior false-positive requiring additional imaging, had a higher proportion of in situ carcinomas (31.7%, 15.3%, 12.9%, respectively; p=0.014) and microcalcifications (37.2%, 20.2%, 9.5%, respectively; p=0.003). The proportion of in situ carcinomas was even higher in women over 60 years (39.2%, 12.5%, 13.0%, respectively; p=0.001). Ipsilateral cancer was observed in 65.7% of cases with prior cytology or biopsy (k=0.479; 95%CI: 0.330-0.794). CONCLUSION: A large number of in situ malignancies and calcification patterns were found among women with prior false-positive result in mammography screening requiring cytology or biopsies, suggesting progression from a previously benign lesion.

Differences in radiological patterns, tumour characteristics and diagnostic precision between digital mammography and screen-film mammography in four breast cancer screening programmes in Spain.

OBJECTIVES: To compare tumour characteristics between cancers detected with screen-film mammography (SFM) and digital mammography (DM) and to evaluate changes in positive predictive values (PPVs) for further assessments, for invasive procedures and for distinct radiological patterns in recalled women. METHODS: 242,838 screening mammograms (171,191 SFM and 71,647 DM) from 103,613 women aged 45-69 years, performed in four population-based breast cancer screening programmes in Spain, were included. The tumour characteristics and PPVs of each group were compared. Radiological patterns (masses, calcifications, distortions and asymmetries) among recalled women were described and PPVs were evaluated. RESULTS: The percentages of ductal carcinoma in situ (DCIS) were higher in DM than in SFM both in the first [18.5% vs. 15.8%(p = 0.580)] and in successive screenings [23.2% vs. 15.7%(p = 0.115)]. PPVs for masses, asymmetries and calcifications were higher in DM, being statistically significant in masses (5.3% vs. 3.9%; proportion ratio: 1.37 95%CI: 1.08-1.72). Among cancers detected by calcifications, the percentage of DCIS was higher in DM (60.3% vs. 46.4%, p = 0.060). CONCLUSIONS: PPVs were higher when DM was used, both for further assessments and for invasive procedures, with similar cancer detection rates and no statistically significant differences in tumour characteristics. The greatest improvements in PPVs were found for masses.

Reduction in false-positive results after introduction of digital mammography: analysis from four population-based breast cancer screening programs in Spain.

PURPOSE: To evaluate the effect of the introduction of digital mammography on the recall rate, detection rate, false-positive rate, and rates of invasive procedures in a cohort of women from four population-based breast cancer screening programs in Spain. MATERIALS AND METHODS: The study was approved by the ethics committee; informed consent was not required. A total of 242,838 mammograms (171,191 screen film [screen-film mammography group] and 71,647 digital [digital mammography group]) obtained in 103,613 women aged 45-69 years were included. False-positive results for any additional procedure and for invasive procedures, the breast cancer rate, and the positive predictive value in each group were compared by using Pearson χ(2) test. The effect of the mammographic technology used (screen-film or digital) on the false-positive results and cancer detection risk was evaluated with multivariate logistic regression models, adjusted according to women's and the screening program's characteristics and time trends. RESULTS: The false-positive rate was higher for screen-film than for digital mammography (7.6% and 5.7%, respectively; P < .001). False-positive results after an invasive procedure were significantly higher for screen-film than for digital mammography (1.9% and 0.7%, respectively; P < .001). No significant differences were observed in the overall cancer detection rate between the two groups (0.45% and 0.43% in the screen-film and digital mammography groups, respectively; P = .59). The adjusted risk of a false-positive result was higher for screen-film than for digital mammography (odds ratio = 1.32). The adjusted risk was also lower for the digital mammography group when time trends were taken into account. CONCLUSION: The lower false-positive risk with use of digital mammography should be taken into account when balancing the risks and benefits of breast cancer screening.

Surgery of cosmetic sequelae after breast-conserving therapy.

Although a considerable number of patients have an unfair cosmetic result after breast-conserving therapy, which correlates with poor psychosocial functioning, surprisingly, really only very few patients undergo surgical correction. The purpose of this article was to report our experience in the surgical treatment of such patients and analyze a special subgroup which required bilateral reduction mammaplasty because of associated symptomatic macromastia and their desire to reduce their breast size. From July 2000 to November 2008, some 23 patients consulted for unsatisfactory cosmetic outcome after breast-conserving therapy, fourteen of them accepting the surgical treatment proposed and these were operated upon. We used the following techniques: reduction mammaplasty of the contralateral breast for symmetrization (9), bilateral reduction mammaplasty (4), one mammaplasty and augmentation of contra-lateral breast and one myocutaneous dorsi flap for surgical correction of ipsilateral breast. One patient had serious complications, having partial necrosis of the areola, fat and breast skin necrosis, and needed reoperation for surgical removal of necrotic tissue. Some factors such as obesity and heavy smoking habits could explain this. We were able to evaluate cosmetic outcome in ten patients; late cosmetic outcome was good in seven patients, fair in two and poor in one. Despite the fact that most patients treated by breast-conserving therapy are satisfied with the fact that they have retained their breasts and minimized an unfair cosmetic outcome, cosmetic evaluation should be introduced as a matter of routine.

New protocol for the isolation of nitrocellulose from gunpowders: utility in their identification.

In this work, a new approach for the isolation of nitrocellulose from smokeless gunpowders has been developed. A multistep solvent extraction method was needed to purify nitrocellulose contained in gunpowders. For single-base or double-base gunpowders six consecutive solvent extractions were selected: three extractions with methanol (to remove nitroglycerin, 2,4-dinitrotoluene, ethyl-centralite, diphenylamine, and diphenylamine derivatives); one extraction with dichloromethane (to remove colorants and plasticizers of organic nature); one extraction with methanol (to facilitate a final polar extraction); and one extraction with water (to remove ionic components) were necessary at 35 degrees C. For the triple-base gunpowder studied, eight solvent extractions were needed due to a high concentration of the water-soluble nitroguanidine was present. In addition to the same five initial phases used for the single-base and double-base gunpowders, three water extraction phases at a higher temperature (75 degrees C instead of 35 degrees C) were also needed. A final step to solubilize nitrocellulose in methyl ethyl ketone was used to remove inert components (mainly graphite). Nitrocellulose isolated from these propellants was characterized by Fourier-Transformed Infrared Spectroscopy (FTIR spectroscopy). The same FTIR spectra were observed for nitrocelluloses isolated from different types of gunpowders. A comparison of FTIR spectra of nitrocellulose samples of different nitration degree evidenced that the bands regions most affected by this factor were: 3600-3400cm(-1), corresponding to the stretching vibrations of residual hydroxyl groups; 1200-1000cm(-1), attributed to the valence vibrations nuCO of the glucopyranose cycle; and 750-690cm(-1), assigned to vibrations of the nitrate group. In both cases, the bands appearing in these regions were more pronounced in the spectra of nitrocellulose samples of low nitration degree.

Reduction mammaplasty: an advantageous option for breast conserving surgery in large-breasted patients.

Oncoplastic breast conserving surgery is a good approach for large-breasted women with breast cancer, as it increases the rate of breast conserving surgery, improves cosmetic results and prevents both cosmetic sequelae and the symptoms associated with macromastia. We reviewed ten publications in which 276 patients had been treated with bilateral reduction mammaplasty. All showed the same conclusion: women with breast cancer and macromastia candidates for breast conserving surgery could obtain clear oncological and cosmetic advantages and an improvement in quality of life if they were treated using bilateral reduction onco-therapeutic mammaplasty.

Postoperative spindle cell nodule of the breast: Pseudosarcomatous myofibroblastic proliferation following endo-surgery.

Despite the frequent use of fine-needle aspiration, core biopsy and surgery, postoperative spindle cell nodule (PSCN) is a rare pathological complication that may be diagnostically treacherous. Presented herein is the case of a 52-year-old woman who developed a 7 mm mammary nodular lesion 66 days after removal of an area of columnar cell hyperplasia involving cellular and architectural atypia, performed with the Mammotome Breast Biopsy System. The lesion was highly cellular and composed of intersecting fascicles of plump spindle cells with blunt-ended elongated nuclei and nucleoli easily visible. Interspersed mononuclear cells and hemosiderin-laden macrophages were evident. PSCN is a reactive, benign myofibroblastic proliferation. Differential diagnosis includes benign and malignant spindle cell lesions of the breast. Recognition of this reactive lesion will avoid overdiagnosis of spindle cell malignant tumor. Attention to clinicopathological and histological features should result in accurate recognition of this lesion.

Subcutaneous ossifying lipoma: case report and review of the literature.

BACKGROUND: Lipomas can undergo a variety of changes, one of which is ossification. Ossifying lipoma (OL), independent of bone tissue, is rare. No case has been reported with this heading in the dermatopathological literature. CASE REPORT: A 73-year-old woman was referred for a subcutaneous mass on the left scapular region that had been present for more than 22 years. RESULTS: The lesion was an OL measuring 8 cm and weighing 75 g. Only 25 cases of OL have been described in soft tissues. Including the present report, locations in order of frequency are the head and neck area (11 cases), the limbs (9 cases) and the trunk (6 cases). Average patient age is 50.9 years (range, 17-81 years). History is measured in years (mean, more than 6 years). Average tumor size is 7.1 cm (range, 0.8-20 cm). The adipose component is usually predominant and the mature bone tissue is irregular in distribution. Bone spicules are surrounded by fibrous tissue bands. Chondrous structures are found in 46.2% of tumors. No recurrences have been reported. CONCLUSIONS: OL is rare but has a characteristic gross, radiological and histological appearance. It has the same prognosis as simple lipoma. Excision is the treatment to be chosen.

Needle-wire-guided breast tumor excision.

Complete resection of large-size tumors can be easily approachable developing needle-guide tumour excision, in the context of Oncoplastic Conservative Breast Surgery. Needles are used as markers showing optimal excision margins, especially at conflicting points.

Cirugía oncoplástica conservadora del cáncer de mama / Conservative oncoplastic surgery of breast cancer

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A novel ergot alkaloid as a 5-HT(1A) inhibitor produced by Dicyma sp.

In the course of a search for small-molecule inhibitors of 5-hydroxytryptamine receptors we have identified a novel ergoline derivative (1) from the fungal culture of Dicyma sp. This compound has a pK(i) of 10.2 versus the 5-hydroxytryptamine(1A) receptor subtype. The structure was elucidated by extensive NMR spectroscopy and mass spectrometry.

Fibrilación auricular: nuevos aspectos sobre una vieja enfermedad / Atrial Fibrillation: new aspects of an old disease

La fibrilación auricular es la arritmia encontrada más frecuentemente en la clínica. Los principales problemas derivados de ella son los eventos trombóticos recurrentes y el deterioro de la clase funcional. La fibrilación auricular induce alteraciones de los canales iónicos, que la perpetoan. El tratamiento de la FA se encamina a corregir estas alteraciones y regresar al ritmo sinusal, al tiempo que se debe controlar la frecuencia cardiaca y prevenir eventos embólicos por medio de anticoagulación o tratamiento con antiagregantes plaquetarios. Actualmente existen recursos con antiarrítmicos de clase IC o clase III para intentar recuperar el ritmo sinusal. Las tasas de éxito son variables y las mejores se obtienen con flecainida o propafenona en los casos sin cardiopatía estructural y amiodarona cuando ésta existe. Las combinaciones de pacientes y fármacos son múltiples, cada caso debe ser individualizado. Los nuevos antiarrítmicos de clase III han mostrado eficacia pero con tasas relativamente altas de reacciones adversas como taquicardia helicoidal. La anticoagulación sería el tratamiento preferido para la mayoría de los enfermos, pero se debe ajustar en cada caso. Las terapias como la ablación con catéter focal o lineal, así como la estimulación auricular o biauricular y los desfibriladores implantables requieren de un seguimiento a mayor plazo y también necesitan de tratamiento antiarrítmico agregado. La cirugía tiene una morbi-mortalidad alta, por lo que el riesgo supera al beneficio.

Alteraciones proliferativas de la mama en lesiones no palpables detectadas por mamografía / Proliferative changes in nonpalpable breast lesions detected by mammography

Objetivo: Realizar un análisis retrospectivo de los hallazgos radiológicos en lesiones no palpables detectadas por mamografía, que originan la indicación de biopsia quirúrgica con resultado histológico de mastopatía proliferativa con y sin atipia.Material y métodos: Se seleccionaron 421 mujeres con 429 biopsias con resultado histológico de mastopatía proliferativa con y sin atipia, procedentes de un total de 1.252 biopsias quirúrgicas en lesiones no palpables con resultado de benignidad en dos hospitales. En todas las pacientes se registró la edad, antecedentes personales y familiares de cáncer de mama, motivo de petición de la mamografía y signo radiológico que originó la indicación de biopsia quirúrgica.Resultados: En 347 mujeres con 354 biopsias, el diagnóstico fue de mastopatía proliferativa (hiperplasia epitelial) y en las 74 mujeres restantes, con 75 biopsias, de hiperplasia atípica, lo que representa el 28 por ciento y 6 por ciento, respectivamente, de las 1.252 biopsias con resultado de benignidad. De los 354 casos con diagnóstico histológico de hiperplasia epitelial y de los 75 casos con diagnóstico de hiperplasia atípica, en 221 (62 por ciento) y 45 (60 por ciento), respectivamente, el signo radiológico más frecuente que originó la indicación de biopsia fue un grupo de calcificaciones (p < 0,05). La distorsión parenquimatosa con o sin calcificaciones fue el segundo signo radiológico en frecuencia, mostrando en el estudio histológico una estrecha asociación de estos procesos proliferativos con la cicatriz radial.Conclusiones: Las calcificaciones son el hallazgo radiológico que más frecuentemente origina la indicación de biopsia quirúrgica por lesiones no palpables en pacientes con resultado de mastopatía proliferativa con y sin atipia (AU)

Síncope neurocardiogénico, fisiopatología, diagnóstico y tratamiento / Neurocardiogenic syncope, physiopathology, diagnostic and treatment

El síncope neurocardiogénico es un problema frecuente de salud. Dada la gran cantidad de diagnósticos diferenciales puede implicar altos costos de estudio si no se realiza una metodología adecuada para su diagnóstico. Hay importantes aspectos de su fisiopatología que se desconoce, pero el reflejo de Bezold-Jarish explica muchos de los aspectos clínicos del problema. La respuesta adrenérgica puede funcionar como disparador para una descarga vagal intensa que provoca hipotensión y/o bradicardia. La prueba de mesa basculante permite poner en evidencia otras formas de disautonomía; de ahí su importancia reciente. Las pruebas actuales consisten en diversas formas de monitoreo electrocardiográfico ambulatorio, ecocardiograma, prueba de mesa basculante y estudio electrofisiológico, pero la principal herramienta sigue siendo una buena historia clínica y una exploración física concienzuda. El tratamiento del síncope es variado, con base en las características basales de la frecuencia cardíaca y la tensión arterial, además de los resultados de los exámenes practicados. Esto determinará el medicamento y su dosis, además de medidas preventivas simples, como mayor ingestión de sodio y líquidos, así como el ejercicio. En casos particulares se recurrirá a procedimiento de ablación o, incluso, al implante de marcapasos o desfibriladores automáticos implantables (DAI)