Antireflux ureteral stent proof of concept assessment after minimally invasive treatment of obstructive uropathy in animal model.

OBJECTIVES: To assess the efficacy of a new anti-reflux intraureteral stent design in a swine model after minimally invasive treatment of ureteral stricture to reduce ureteral stent morbidity, previous to manufacture this design in a biodegradable fashion. METHODS: Twenty-eight female pigs were included. The study began with a cystoscopic, nephrosonographic and contrast fluoroscopic assessment. Afterwards, obstructive uropathy model in right ureter was created. Obstruction was confirmed 6 weeks later and animals were randomly distributed into 2 groups. Group I underwent laser endopyelotomy and Group-II laparoscopic pyeloplasty A 3Fr anti-reflux intraureteral stent was placed 6 weeks. Follow-up evaluations were performed at 3-6 weeks. The final follow-up was completed at 5 months and included the aforementioned diagnostic methods and pathological study. RESULTS: None of the study animals showed any vesicoureteral reflux signs or ureteral orifice injury. There were no urinomas or ureteric fistulas. The dislodgement rate was 10.7%. After 6 weeks of stenting, 71.4% of ureters showed ureteral peristalsis below the stent, and 100% at the final follow-up. After pathological assessment, no differences were shown at UPJ and healing in the incised area was correct in both groups. CONCLUSIONS: The new stent design avoids vesicoureteral reflux and bladder trigone irritation, consequently might reduce morbidity associated with double pigtail ureteral stents. This study also shows that it is only necessary temporary scaffolding the incised ureteral segment and not the entire length of the ureter after minimally invasive surgery. It is also necessary to manufacture this design in a biodegradable material, thus avoiding its removal.

Antireflux ureteral stent proof of concept assessment after minimally invasive treatment of obstructive uropathy in animal model / Evaluación preliminar de un catéter ureteral antirreflujo tras el tratamiento minimamente invasivo de la uropatia obstructiva en modelo animal

OBJECTIVES: To assess the efficacy of a new anti-reflux intraureteral stent design in a swine model after minimally invasive treatment of ureteral stricture to reduce ureteral stent morbidity, previous to manufacture this design in a biodegradable fashion. METHODS: Twenty-eight female pigs were included. The study began with a cystoscopic, nephrosonographic and contrast fluoroscopic assessment. Afterwards, obstructive uropathy model in right ureter was created. Obstruction was confirmed 6 weeks later and animals were randomly distributed into 2 groups. Group I underwent laser endopyelotomy and Group-II laparoscopic pyeloplasty A 3Fr anti-reflux intraureteral stent was placed 6 weeks. Follow-up evaluations were performed at 3-6 weeks. The final follow-up was completed at 5 months and included the aforementioned diagnostic methods and pathological study. RESULTS: None of the study animals showed any vesicoureteral reflux signs or ureteral orifice injury. There were no urinomas or ureteric fistulas. The dislodgement rate was 10.7%. After 6 weeks of stenting, 71.4% of ureters showed ureteral peristalsis below the stent, and 100% at the final follow-up. After pathological assessment, no differences were shown at UPJ and healing in the incised area was correct in both groups. CONCLUSIÓN: The new stent design avoids vesicoureteral reflux and bladder trigone irritation, consequently might reduce morbidity associated with double pigtail ureteral stents. This study also shows that it is only necessary temporary scaffolding the incised ureteral segment and not the entire length of the ureter after minimally invasive surgery. It is also necessary to manufacture this design in a biodegradable material, thus avoiding its removal

OBJETIVOS: Evaluar un nuevo diseño de catéter intraureteral-antirreflujo en modelo porcino tras el tratamiento mínimamente invasivo de estenosis ureterales. MÉTODOS: Se emplearon 28 ejemplares de la especie porcina. El estudio se inicia con la evaluación cistoscópica, nefrosonográfica y fluoroscópica de la vía urinaria. Posteriormente, se procede a la creación del modelo de estenosis en el uréter derecho. La obstrucción se confirma 6 semanas después y los animales son distribuidos aleatoriamente en dos grupos homogeneos. El Grupo-I, fue tratado mediante endopielotomía láser, y el Grupo-II mediante una pieloplastia laparoscópica. En ambos grupos se coloca durante 6 semanas, un catéter ureteral antirreflujo de 3Fr. Los seguimientos de los animales del estudio se realizaron a las 3-6 semanas. Con un seguimiento final a los 5 meses, que incluye un estudio anatomopatológico. RESULTADOS: Ninguno de los animales del estudio mostró reflujo vesicoureteral o signos de lesión en el orificio ureteral. No se produjeron ni fístulas ni urinomas. La tasa de migración alcanzó un 10,7%. Tras 6 semanas de cateterización el 71,4% de los uréteres mostraron peristaltismo ureteral distal y un 100% a los 5 meses. Tras el estudio anatomopatológico, no se evidencian diferencias en la zona de la unión pieloureteral y la cicatrización fue correcta en ambos grupos. CONCLUSIONES: El nuevo catéter ureteral impide el reflujo vesicoureteral y la irritación del trígono vesical, por lo que previsiblemente podría reducir la morbilidad asociada a los catéteres ureterales. El estudio también muestra que solo es necesaria la cateterización temporal del segmento incidido y no de todo el uréter. Evidentemente es necesario desarrollar este nuevo diseño en su versión biodegradable, para su empleo clínico futuro

Natural history of prostate cancer.

Prostatic cancer can be a silent tumor, with no symptoms remaining undetectable throughout life . But when it keeps growing, enough to produce symptoms such as bladder neck obstruction, invasion of adjacent organs or distant metastasis, curative treatment is usually impossible. Since PSA emerges, data shows a dramatic increasing in the diagnosis of prostatic cancer, specially low risk tumor. Since then, We are wondering which tumors are suitable to be treated and which ones remain asymptomatic without treatment. Analysing the natural history of prostate cancer, helps us to choose the best atitude treating the tumor, this subjet has been in constant discusión in the last decade. Our article consistes of a reviewing the main publications treating natural history of prostate cancer in prehyphen;and post-PSA era. The indicated studied suggest that most prostate tumors diagnosed today are low grade cancer, as a result with a low mortality. This conclusión shows us the importance of modifying the algorithm of treatment of these tumors.

Historia natural del cáncer de próstata / Natural history of prostate cancer

El cáncer de próstata puede ser un tumor indolente, que no presenta síntomas y permanecer indetectable a lo largo de la vida. Pero cuando ha crecido lo suficiente como para producir sintomatología como obstrucción infravesical, invasión de órganos vecinos o metástasis a distancia, la curación es habitualmente imposible. La aparición del PSA ha supuesto un incremento dramático en el diagnóstico de los tumores de próstata de bajo riesgo. Todos nos preguntamos cuáles son los tumores que debemos de tratar y cuáles son los tumores que permanecerán asintomáticos. Conocer la historia natural del cáncer de próstata, nos ayudará a indicar correctamente su tratamiento, que en la actualidad está en permanente discusión. Realizamos en este trabajo una revisión de los principales estudios publicados en la literatura sobre la historia natural del cáncer de próstata en la era pre y post-PSA. Los datos que tenemos sugieren que la mayoría de los tumores de próstata que diagnosticamos en la actualidad son de bajo grado y por lo tanto con una baja mortalidad. Es necesario replantearse el algoritmo del tratamiento de estos tumores

Prostatic cancer can be a silent tumor, with no symptoms remaining undetectable throughout life. But when it keeps growing, enough to produce symptoms such as bladder neck obstruction, invasion of adjacent organs or distant metastasis, curative treatment is usually impossible. Since PSA emerges, data shows a dramatic increasing in the diagnosis of prostatic cancer, specially low risk tumor. Since then, We are wondering which tumors are suitable to be treated and which ones remain asymptomatic without treatment. Analysing the natural history of prostate cancer, helps us to choose the best atitude treating the tumor, this subjet has been in constant discusión in the last decade. Our article consistes of a reviewing the main publications treating natural history of prostate cancer in pre-and post- PSA era. The indicated studied suggest that most prostate tumors diagnosed today are low grade cancer, as a result with a low mortality. This conclusión shows us the importance of modifying the algorithm of treatment of these tumors

[Treatment of small renal masses with laparoscopic radiofrequency ablation]. / Tratamiento de las masas renales de pequeño tamaño mediante radiofrecuencia por laparoscopia.

OBJECTIVES: To perform a bibliographic review of the laparoscopic approach for radiofrequency ablation of small renal masses. METHODS: For this review we used the Medline database. We reviewed the clinical guidelines of the American Urological Association, the European Association of Urology and other institutions. RESULTS: Radiofrequency ablation is a minimally invasive treatment in which a needle is introduced in the tumor once it is identified, and it produces an increase of temperature high enough to destroy tumor cells. This technique may be used by percutaneous approach, or during a laparoscopic approach. The choice of one technique or another depends on tumor site, closeness to the bowels or other organs and patient conditions. It would be indicated in patients with small tumors or important comorbidity who are not candidates for surgery. There are not randomized studies comparing these ablation techniques with the surgical techniques. There is no randomized study comparing the efficacy of percutaneous and laparoscopic techniques either but a metanalysis comparing them has been performed. CONCLUSIONS: The treatment of small renal masses keeps being surgical excision. Radiofrequency ablation represents an alternative for carefully selected patients due to its low morbidity and few complications. There are not long term efficacy studies to date. Laparoscopic radiofrequency ablation would be indicated in cases in which the percutaneous approach is complicated due to tumor site.

Tratamiento de las masas renales de pequeño tamaño mediante radiofrecuencia por laparoscopia / Treatment of small renal masses with laparoscopic radiofrequency ablation

OBJETIVOS: Realizar una revisión bibliográfica sobre la vía laparoscópica para la ablación por radiofrecuencia de las masas renales de pequeño tamaño. MÉTODOS: Para esta revisión se ha utilizado la base de datos Medline. Se han revisado las Guías Clínicas de la Asociación Americana de Urología y de la Asociación Europea de Urología y otras instituciones. RESULTADO: La ablación por radiofrecuencia es un tratamiento minimamente invasivo en el que una vez localizado el tumor se introduce una aguja en su interior y se produce un aumento de la temperatura lo suficientemente elevada como para destruir las células tumorales. Esta técnica se puede realizar mediante una vía percutánea, o bien, en el curso de una cirugía laparoscópica. La elección de una técnica u otra va a depender de la localización del tumor, de la proximidad al intestino u otros órganos y de las condiciones del paciente. Estaría indicado en los pacientes con tumores pequeños o comorbilidad importante que no son candidatos a la cirugía. No existen estudios randomizados para comparar las técnicas de ablación con las técnicas quirúrgicas. No hay un estudio randomizado que compare la eficacia de las técnicas percutáneas con las laparoscópicas pero si se ha realizado un meta-análisis. No existen estudios randomizados comparando la ablación por radiofrecuencia con la ablación por crioterapia, pero si existe un meta-análisis que las compara. CONCLUSIONES: El tratamiento de las masas renales de pequeño tamaño continúa siendo la escisión quirúrgica. La ablación por radiofrecuencia representa una alternativa para pacientes cuidadosamente seleccionados, debido a su baja morbilidad y pocas complicaciones. A día de hoy, no existen estudios de eficacia a largo plazo. La ablación por radiofrecuencia aplicada por vía laparoscópica estaría indicada en casos en los que la vía percutánea sea complicada por la localización del tumor(AU)

OBJECTIVES: To perform a bibliographic review of the laparoscopic approach for radiofrequency ablation of small renal masses. METHODS: For this review we used the Medline database. We reviewed the clinical guidelines of the American Urological Association, the European Association of Urology and other institutions. RESULTS: Radiofrequency ablation is a minimally invasive treatment in which a needle is introduced in the tumor once it is identified, and it produces an increase of temperature high enough to destroy tumor cells. This technique may be used by percutaneous approach, or during a laparoscopic approach. The choice of one technique or another depends on tumor site, closeness to the bowels or other organs and patient conditions. It would be indicated in patients with small tumors or important comorbidity who are not candidates for surgery. There are not randomized studies comparing these ablation techniques with the surgical techniques. There is no randomized study comparing the efficacy of percutaneous and laparoscopic techniques either but a metanalysis comparing them has been performed. CONCLUSIONS: The treatment of small renal masses keeps being surgical excision. Radiofrequency ablation represents an alternative for carefully selected patients due to its low morbidity and few complications. There are not long term efficacy studies to date. Laparoscopic radiofrequency ablation would be indicated in cases in which the percutaneous approach is complicated due to tumor site(AU)