Sobrediagnóstico en cribado de cáncer / Overdiagnosis in cancer screening

En los programas de diagnóstico precoz, se considera sobrediagnóstico al diagnóstico de una enfermedad que sin cribado nunca se hubiera diagnosticado, y como se espera que dicho diagnóstico no cause la muerte, se trata innecesariamente. El sobrediagnóstico es un sesgo del propio cribado y un efecto no deseado de la prevención secundaria y de la mejora de la sensibilidad de las técnicas diagnósticas. A priori es difícil de discriminar qué diagnósticos son los clínicamente relevantes y en cuáles se podría evitar el tratamiento. Para minimizar el efecto de sobrediagnóstico, el cribado debe dirigirse a población considerada de riesgo (AU)

In screening programs, overdiagnosis is defined as the detection of a disease that would have gone undetected without screening when that disease would not have resulted in morbimortality and was treated unnecessarily. Overdiagnosis is a bias inherent in screening and an undesired effect of secondary prevention and improved sensitivity of diagnostic techniques. It is difficult to discriminate a priori between clinically relevant diagnoses and those in which treatment is unnecessary. To minimize the effects of overdiagnosis, screening should be done in patients at risk (AU)

[Overdiagnosis in cancer screening]. / Sobrediagnóstico en cribado de cáncer.

In screening programs, overdiagnosis is defined as the detection of a disease that would have gone undetected without screening when that disease would not have resulted in morbimortality and was treated unnecessarily. Overdiagnosis is a bias inherent in screening and an undesired effect of secondary prevention and improved sensitivity of diagnostic techniques. It is difficult to discriminate a priori between clinically relevant diagnoses and those in which treatment is unnecessary. To minimize the effects of overdiagnosis, screening should be done in patients at risk.

RECIST y el radiólogo / RECIST and the radiologist

Mediante las imágenes biomédicas podemos diagnosticar, estadificar, controlar y valorar la efectividad de los procedimientos terapéuticos a los que son sometidos los pacientes oncológicos. RECIST (Response Evaluation Criteria In Solid Tumors) es el método para monitorizar el tratamiento mediante medidas unidimensionales de los tumores, obtenidas con técnicas de imagen reproducibles como son la TC, la RM y la PET. Los cambios metabólicos inducidos por los nuevos tratamientos modifican la biología y comportamiento del tumor, con discordancia ocasional entre el estado clínico del paciente y la respuesta medida con RECIST, lo que apunta a la necesidad de incluir pruebas funcionales en la valoración de la respuesta al tratamiento. El objetivo es revisar los criterios RECIST conociendo la aportación de la imagen funcional para valorar correctamente la eficacia y la repercusión del tratamiento en los pacientes con tumores sólidos (AU)

Biomedical imaging makes it possible not only to diagnose and stage cancer, but also to follow up patients and evaluate the response to treatment. RECIST (Response Evaluation Criteria In Solid Tumors) provides a method to monitor the response to treatment based on one dimensional measurements of tumors obtained with reproducible imaging techniques like CT, MRI, and PET. The metabolic changes induced by new treatments modify the biology and behavior of the tumor; occasionally, there is a discrepancy between the patient’s clinical condition and the response measured by RECIST, which indicates that functional tests need to be included in the evaluation of the response to treatment. The objective is to review the RECIST criteria to include the contribution of functional imaging to enable the efficacy and effects of the treatment in patients with solid tumors (AU)

[RECIST and the radiologist]. / RECIST y el radiólogo.

Biomedical imaging makes it possible not only to diagnose and stage cancer, but also to follow up patients and evaluate the response to treatment. RECIST (Response Evaluation Criteria In Solid Tumors) provides a method to monitor the response to treatment based on one dimensional measurements of tumors obtained with reproducible imaging techniques like CT, MRI, and PET. The metabolic changes induced by new treatments modify the biology and behavior of the tumor; occasionally, there is a discrepancy between the patient's clinical condition and the response measured by RECIST, which indicates that functional tests need to be included in the evaluation of the response to treatment. The objective is to review the RECIST criteria to include the contribution of functional imaging to enable the efficacy and effects of the treatment in patients with solid tumors.

Utilidad de la anestesia local del plexo periprostático en el control del dolor en las biopsias prostáticas guiadas con ecografía / Utility of local anestesia of the periprostatic plexus in the control of the pain in the ultrasound-guided prostate biopsy

Objetivo: La anestesia del plexo periprostático (APP) no es práctica habitual durante la biopsia prostática (BP).Muchos pacientes deben someterse a una segunda, o más, BP por sospecha de carcinoma. El dolor influye en la repetición de la misma pues determina que muchos pacientes rechacen el procedimiento o que éste deba realizarse en quirófano bajo anestesia. Nuestro objetivo fue valorar la utilidad de la APP en la supresión del dolor producido durante la realización de la BP así como la aceptación del procedimiento realizado en estas condiciones. Material y métodos: De octubre del 2002 a junio del 2003 planteamos un trabajo prospectivo con casos y controles en el que incluimos aleatoriamente 275 pacientes de dos centros para BP. En el primer centro se incluyeron 101 varones a los que no se les realizó APP, mientras que en el segundo fueron 174 los pacientes sometidos a BP tras APP. Usamos hasta 10 ml de lidocaína al 2% diluida al 50% administrada mediante una aguja fina del calibre 22. Al final del procedimiento se invitó al paciente a rellenar un cuestionario de satisfacción y evaluación del dolor. Resultados: En el grupo de pacientes del segundo centro se obtuvieron valores medios significativamente inferiores (p<0,005, IC 95%) en la valoración cuantitativa del dolor, que en el grupo del primer centro (1,24±0,4 vs. 2,5±1,1).Respecto a la posibilidad, si fuese necesario, de repetir la BP, a ninguno de los pacientes del segundo centro le importaría, mientras que el 10% del primer centro no la repetirían o la aceptarían sólo bajo anestesia. No se produjeron complicaciones atribuibles a la APP. Conclusión: La APP es una técnica segura que reduce significativamente el dolor durante la BP, mejorando la aceptación de la misma (AU)

Objetive: Periprostatic plexus anesthesia (PPA) is not current practice during prostate ultrasound-guided biopsy (PB). Many patients must undergo a second or more PB if a prostate carcinoma is suspected. Due to pain, many patients reject the procedure, or it has to be performed with general anesthesia. Our objective was to evaluate the utility of PPA to eliminate the pain caused by PB, as well as the acceptance of the procedure under these conditions. Patients and Methods: Between october 2002 and june 2003 we designed a randomized prospective study with 275 patients that were seen in 2 different hospitals and required PB. In the 1st group we included 101 males who underwent PB without PA. In the other group, 174 male patients submitted PB after PPA were included. 10 cc lidocaine, 2% diluted 50% was injected with a 22g needle. At the end of the procedure, patients were asked to fill in a questionnaire about their satisfaction and degree of pain felt. Results: In the second group of patients we obtained significantly inferior values (p<0.005, IC 95%) in the quantitative evaluation of pain compared with the first group (1.24±0.4 vs. 2.5 ±1.1). Ask per the possibility of repeating PB if it were necessary, none of the patients in the 2nd group would object, whereas 10% in the 1st group would not have the biopsy repeated or would only accept it if it was done with general anesthesia. No complications due to PPA were found. Conclusion: PPA is a safe procedure that significantly reduces pain during PB, improving its acquiescence among patients (AU)

[Utility of local anesthesia of the periprostatic plexus in the control of the pain in the ultrasound-guided prostate biopsy]. / Utilidad de la anestesia local del plexo periprostático en el control del dolor en las biopsias prostáticas guiadas con ecografía.

OBJECTIVE: Periprostatic plexus anesthesia (PPA) is not current practice during prostate ultrasound-guided biopsy (PB). Many patients must undergo a second or more PB if a prostate carcinoma is suspected. Due to pain, many patients reject the procedure, or it has to be performed with general anesthesia. Our objective was to evaluate the utility of PPA to eliminate the pain caused by PB, as well as the acceptance of the procedure under these conditions. PATIENTS AND METHODS: Between october 2002 and june 2003 we designed a randomized prospective study with 275 patients that were seen in 2 different hospitals and required PB. In the 1st group we included 101 males who underwent PB without PA. In the other group, 174 male patients submitted PB after PPA were included. 10 cc lidocaine, 2% diluted 50% was injected with a 22g needle. At the end of the procedure, patients were asked to fill in a questionnaire about their satisfaction and degree of pain felt. RESULTS: In the second group of patients we obtained significantly inferior values (p < 0.005, IC 95%) in the quantitative evaluation of pain compared with the first group (1.24 +/- 0.4 vs. 2.5 +/- 1.1). Ask per the possibility of repeating PB if it were necessary, none of the patients in the 2nd group would object, whereas 10% in the 1st group would not have the biopsy repeated or would only accept it if it was done with general anesthesia. No complications due to PPA were found. CONCLUSION: PPA is a safe procedure that significantly reduces pain during PB, improving its acquiescence among patients.

Valor diagnóstico de segundas biopsias prostáticas en varones de riesgo. Estudio estratificado por valor de PSA / Diagnostic value of the second prostate biopsies in males of risk. Study stratified by value of PSA

OBJETIVO: Valorar el rendimiento diagnóstico de la segunda biopsia prostática (BP). PACIENTES Y MÉTODOS: Un total de 116 varones con BP previa de benignidad fueron sometidos a 2 o más BP por sextantes guiadas con ultrasonidos (US). Los criterios de inclusión fueron: BP previa sospechosa (PIN), PSA elevado, TR o US sospechoso.RESULTADOS: El tiempo medio transcurrido entre la primera y siguiente biopsia fue de 13 ± 11 meses. Se obtuvieron 35 malignas y 4 premalignas en las segundas biopsias realizadas, lo que da un rendimiento diagnóstico global del 33,6%. Cuando estratificamos por valor de PSA, obtenemos que con PSA 10 ng/ml, de 34,6%. CONCLUSIÓN: La repetición de la biopsia seriada de próstata en pacientes de riesgo, mejora el rendimiento diagnóstico y elimina los falsos negativos de carcinoma. prostático

OBJETIVE: To value the diagnostic yield of the second prostate biopsy (BP). PATIENTS AND METHODS: To 116 males with BP previous to kindliness surrendered to 2 or more BP for sextants guided with ultrasounds (US). The criteria of inclusion were: BP previous suspicious (PIN), high PSA, TR or suspicious US. RESULTS: The average time passed between the first and following biopsy was 13 ± 11 months. 35 malignant and 4 premalignant ones were obtained in the second realized biopsies, which gives a diagnostic global yield of 33.6%. When we stratify for value of PSA, we obtain that with PSA 10 ng/ml of 34,6%. CONCLUSION: The repetition of the serial biopsy of prostate in patients of risk, improves the diagnostic yield and eliminates the false negatives of prostate carcinoma

Structural determinants and molecular mechanisms for the resistance of HIV-1 RT to nucleoside analogues.

The reverse transcriptase (RT) of human immunodeficiency virus type-1 (HIV-1) is an RNA- and DNA-dependent DNA polymerase capable of copying the viral genome before it gets integrated into the human host DNA. Hence, HIV-1 RT plays a major role in viral replication and represents a key target for anti-AIDS treatments. Amongst the eleven licensed drugs that inhibit RT, eight are chain-terminating nucleoside analogues (NRTIs) that compete with their natural counterparts during the DNA polymerization process. Unfortunately, under therapeutic pressure, the HIV-1 inevitably develops resistance to these inhibitors by accumulating mutations in the viral pol gene encoding RT. Mechanisms for this resistance can be sorted in two categories, depending on the nature of the drug and the selected mutations. The first category includes mutations involving a specific alteration of the discrimination between natural nucleotides and NRTIs. The second category includes mutations able to promote the removal of the incorporated NRTI and thus repair the nascent DNA chain. This review summarizes the modes of inhibition of HIV-1 RT with NRTIs, and describes the mechanisms of resistance to these drugs, based on enzymatic data correlated to crystal structures and molecular models involving HIV-1 RT. We also give insights into different aspects of resistance such as antagonistic mutations, replication capacity, and the implications for a rational, structure-based drug design.

Incontinencia urinaria: ¿Un problema oculto? / Urinary incontinence: a hidden problem?

La incontinencia urinaria (IU) tiene una alta prevalencia en la población general, sin embargo, no suele ser un motivo de consulta en los servicios de Rehabilitación. El objetivo del trabajo fue estudiar la prevalencia de las pérdidas de orina entre los pacientes que nos son remitidos a consulta, y valorar su impacto higiénico-psicosocial. Encuestamos prospectivamente 188 pacientes consecutivos, de 40 ó más años, que acudieron a consulta médica en dos centros de Atención Primaria con Unidades Básicas de Rehabilitación. El 22,3 por ciento refería escapes incontrolados de orina. La mayoría eran mujeres, con 62 años de media de edad, y el 42,9 por ciento con más de 5 años de evolución. Predominaban la frecuencia diaria, y una intensidad moderada. Sólo una tercera parte había consultado con su médico, pero no todos realizaban tratamiento. La mayoría mantenía su estilo de vida previo, pero un gran porcentaje precisaba ir al baño con frecuencia (54,8 por ciento) y usar compresas (64,3 por ciento).Las variables higiénico-psicosociales: consulta médica, llevar tratamiento, suponerles un problema, cambio de estilo de vida, uso de baño frecuente, preocupación por los baños fuera de casa, y uso de compresas, observaban una relación significativa (p < 0,05) con la intensidad. Concluimos que la IU es un problema frecuente entre los pacientes que acuden a nuestras consultas, con impacto sobre la calidad de vida en los casos graves. Creemos conveniente realizar campañas de información en la sociedad, sobre qué es y cómo se puede mejorar la IU, así como fomentar una conciencia más activa por parte del personal sanitario (AU)

[Diagnostic value of the second prostate biopsies in males of risk. Study stratified by value of PSA]. / Valor diagnóstico de segundas biopsias prostáticas en varones de riesgo. Estudio estratificado por valor de PSA.

OBJECTIVE: [corrected] To value the diagnostic yield of the second prostate biopsy (BP). PATIENTS AND METHODS: To 116 males with BP previous to kindliness surrendered to 2 or more BP for sextants guided with ultrasounds (US). The criteria of inclusion were: BP previous suspicious (PIN), high PSA, TR or suspicious US. RESULTS: The average time passed between the first and following biopsy was 13 +/- 11 months. 35 malignant and 4 premalignant ones were obtained in the second realized biopsies, which gives a diagnostic global yield of 33.6%. When we stratify for value of PSA, we obtain that with PSA <4 ng/ml the yield was 23%, for PSA 4-10 ng/ml the yield was 32% and for PSA >10 ng/ml of 34.6%. CONCLUSION: The repetition of the serial biopsy of prostate in patients of risk, improves the diagnostic yield and eliminates the false negatives of prostate carcinoma.

Medición de masa ósea por ultrasonidos: valor predictivo y diagnóstico en la osteoporosis / Bone mass measurement by ultrasound: predictive and diagnostic value in osteoporosis

Introducción: La medición de la densidad de masa ósea mediante absorciometría bifotónica de rayos X (DXA) es el método diagnóstico de referencia de la osteoporosis (OP) por su precisión. En los últimos años se han desarrollado nuevos métodos, como la medición por ultrasonidos (US) cuyas ventajas son la portabilidad, rapidez, bajo coste y ausencia de irradiación. Los objetivos del trabajo son analizar los valores de masa ósea obtenidos por medición ultrasónica frente a los resultados obtenidos por DXA, así como frente a factores clínicos de riesgo conocidos para establecer el posible valor diagnóstico y/o predictivo de los US en la OP. Pacientes y métodos: Estudio transversal en el que seleccionamos 30 mujeres postmenopáusicas de edades comprendidas entre los 48 y 77 años para estudio de OP según los criterios de la Fundación Nacional de OP de EEUU. Se realiza a todas ellas un cuestionario evaluador de factores clínicos de riesgo de OP y medición de masa ósea mediante DXA en raquis lumbar y analizador de US de contacto en talón. Los datos obtenidos se analizan con el paquete estadístico SPSS 8.0.Resultados: Obtenemos una correlación positiva entre los valores de masa ósea obtenidos mediante US y DXA (coeficiente de correlación de Pearson 0,511, p<0,005). En cuanto a su validez como prueba diagnóstica obtenemos una baja sensibilidad (61,5 por ciento) y una alta especificidad (88,2 por ciento) para el diagnóstico de OP, pero estos valores cambian, aumentando la sensibilidad al 84,6 por ciento, si hablamos de detección de baja masa ósea. En este estudio el único factor de riesgo estadísticamente significativo de OP es el diagnóstico por US (p<0,01). Conclusiones: El diagnóstico de OP mediante US tiene un alto índice de falsos negativos, no sustituyendo actualmente a la técnica de DXA. Sin embargo la medición ultrasónica puede ser utilizada como herramienta de screening para detectar baja masa ósea, y de esta forma localizar personas con riesgo de OP que se beneficiarían de un estudio más amplio. El diagnóstico mediante US presenta un valor predictivo mayor de OP que la presencia de factores clínicos de riesgo. (AU)

Characterization of solid liver lesions with color and pulsed Doppler imaging.

BACKGROUND: To assess the usefulness of color Doppler and duplex sonography in the characterization of solid liver lesions. METHODS: We performed color Doppler and duplex sonography on 106 solid hepatic lesions. With color Doppler, we evaluated the aspect and distribution of tumoral vessels. The pulsed Doppler parameters considered were only those showing the highest systolic peak velocity values. RESULTS: Intratumoral color and pulsed Doppler signals were obtained in 81% (59/73) of malignant tumors (p < 0. 0001) but only in 18% (6/33) of benign tumors. Ninety-six percent (45/47) of the lesions with arterial intratumoral and peritumoral signals were malignant, whereas 4% were benign (p < 0.0001). Only eight (11%) malignant lesions had intratumoral venous signal vis-a-vis 23 (70%) benign. Twelve cases showing intratumoral venous Doppler signal as a single finding were benign. No statistically significant differences were observed in the quantitative parameters recorded by pulsed Doppler (Student t test, p < 0.05), there having been a clear overlapping in the values obtained in benign and malignant lesions. CONCLUSIONS: (a) The type of signal (arterial or venous) and its distribution detected by color and pulsed Doppler is more helpful than the assessment of the spectral quantitative parameters obtained by pulsed Doppler. (b) The presence of intratumoral venous flow remarkably suggests benignancy. (c) The presence of both intra- and peritumoral arterial flow in the same lesion strongly suggests malignancy.

[Familial medullary carcinoma of the thyroid. The usefulness of ultrasonography and Doppler color]. / Carcinoma medular de tiroides familiar. Utilidad de la ultrasonografía y Doppler color.

Medullary carcinoma of the thyroid (MCT) is an uncommon malignant neoplasm, which occurs sporadically and in three familial syndromes with a dominant autosomal transmission mode. We studied a family of 13 members in which four of them (two males and two females: sons, mother and niece) were involved with MCT. All of them underwent mode-B echography and colour-Doppler echography and pulsed colour Doppler, with measurement of carcinoembryonic antigen (CEA) and calcitonin, in an attempt to delineate a pattern useful to differentiate malignant from benign thyroid pathology. Colour Doppler signal was of little usefulness for histologic characterization in function of vascularization, although it was useful for delineating nodules in non-homogeneous glands.

Social handicaps of multiple sclerosis and their relation to neurological alterations.

The social conditions of 73 patients with multiple sclerosis (MS) were studied in relation to the most common neurological disorders observed among them. The Environmental Status Scale (ESS) and Kurtzke's Neurological Functional System (NFS)--both included within the Minimal Record of Disability (MRD)--were used. Pyramidal alterations were the more frequent neurological findings, whereas the need for personal care was the most common social handicap. The chi 2 test applied to contrast each of the dicotomic ESS and NFS variables showed a significant relationship between pyramidal alteration (weakness) and the need for personal care (p < 0.001), the use of community services (p < 0.01), and transportation problems (p < 0.05). Cerebellar disorders were significantly related to the need for community services (p < 0.01) and transportation problems (p < 0.01). Vision disorders were significantly related to the need for personal care (p < 0.05), transportation problems (p < 0.05), and social activity (p < 0.05). In turn, spasticity was significantly related to the need for personal care (p < 0.001), financial (p < 0.001) and transportation problems (p < 0.001), laboral situation (p < 0.05), and the use of community services (p < 0.05). Contrasting the four NFS and 7 ESS nondicotomic variables showed a marked correlation between the pyramidal alterations and personal care (r = 0.71) and transport (r = 0.62). Pyramidal alterations influence the social situation of MS patients and may be the foremost alterations to be considered for the optimal social integration of these patients.

Tumores de la glándula parótida: semiología ecográfica / Tumors of parotid gland: echographical semiology

Los tumores de las glándulas salivales son relativamente raros. Su diagnóstico se realiza mediante el estudio anatomopatológico de la pieza de exéresis. No obstante, la ultrasonografía con escala de grises, constituye un importante método de diagnóstico y relativamente nuevo, cuando nos referimos al estudio concreto de los tumores situados en las glándulas salivales. En el presente trabajo, los autores describen la semiología ecografíca de dichos tumores en 18 pacientes, que comprende la serie estudiada en el Hospital Clínico Universitario de la Facultad de Medicina de Valencia. Así mismo, se discuten nuestros resultados con los obtenidos por otros autores y se practica una exhaustiva revisión de la bibliografía pertinente

Influenza B virus: alpha-amanitin sensitivity of replication and primer-dependence of in vitro transcription.

The replication of influenza B/Lee/40 virus in MDCK (canine kidney) cells was sensitive to alpha-amanitin and actinomycin D. In vitro, virion transcriptase activity was stimulated by dinucleotide primers such as ApG. The above characteristics are shared by A/WSN virus.