RESUMEN
BACKGROUND: Approximately 70% of patients with colorectal liver metastases (CRLM) experiences intrahepatic recurrence after initial liver resection. This study assessed outcomes and hospital variation in repeat liver resections (R-LR). METHODS: This population-based study included all patients who underwent liver resection for CRLM between 2014 and 2022 in the Netherlands. Overall survival (OS) was collected for patients operated on between 2014 and 2018 by linkage to the insurance database. RESULTS: Data of 7479 liver resections (1391 (18.6%) repeat and 6088 (81.4%) primary) were analysed. Major morbidity and mortality were not different. Factors associated with major morbidity included ASA 3+, major liver resection, extrahepatic disease, and open surgery. Five-year OS after repeat versus primary liver resection was 42.3% versus 44.8%, P = 0.37. Factors associated with worse OS included largest CRLM >5 cm (aHR 1.58, 95% CI: 1.07-2.34, P = 0.023), >3 CRLM (aHR 1.33, 95% CI: 1.00-1.75, P = 0.046), extrahepatic disease (aHR 1.60, 95% CI: 1.25-2.04, P = 0.001), positive tumour margins (aHR 1.42, 95% CI: 1.09-1.85, P = 0.009). Significant hospital variation in performance of R-LR was observed, median 18.9% (8.2% to 33.3%). CONCLUSION: Significant hospital variation was observed in performance of R-LR in the Netherlands reflecting different treatment decisions upon recurrence. On a population-based level R-LR leads to satisfactory survival.
Asunto(s)
Neoplasias Colorrectales , Hepatectomía , Neoplasias Hepáticas , Reoperación , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/cirugía , Masculino , Países Bajos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/mortalidad , Femenino , Hepatectomía/mortalidad , Hepatectomía/efectos adversos , Persona de Mediana Edad , Anciano , Recurrencia Local de Neoplasia , Resultado del Tratamiento , Estudios Retrospectivos , Hospitales/estadística & datos numéricos , Bases de Datos FactualesRESUMEN
Novel species of fungi described in this study include those from various countries as follows: Argentina, Neocamarosporium halophilum in leaf spots of Atriplex undulata. Australia, Aschersonia merianiae on scale insect (Coccoidea), Curvularia huamulaniae isolated from air, Hevansia mainiae on dead spider, Ophiocordyceps poecilometigena on Poecilometis sp. Bolivia, Lecanora menthoides on sandstone, in open semi-desert montane areas, Sticta monlueckiorum corticolous in a forest, Trichonectria epimegalosporae on apothecia of corticolous Megalospora sulphurata var. sulphurata, Trichonectria puncteliae on the thallus of Punctelia borreri. Brazil, Catenomargarita pseudocercosporicola (incl. Catenomargarita gen. nov.) hyperparasitic on Pseudocercospora fijiensis on leaves of Musa acuminata, Tulasnella restingae on protocorms and roots of Epidendrum fulgens. Bulgaria, Anthracoidea umbrosae on Carex spp. Croatia, Hymenoscyphus radicis from surface-sterilised, asymptomatic roots of Microthlaspi erraticum, Orbilia multiserpentina on wood of decorticated branches of Quercus pubescens. France, Calosporella punctatispora on dead corticated twigs of Aceropalus. French West Indies (Martinique), Eutypella lechatii on dead corticated palm stem. Germany, Arrhenia alcalinophila on loamy soil. Iceland, Cistella blauvikensis on dead grass (Poaceae). India, Fulvifomes maritimus on living Peltophorum pterocarpum, Fulvifomes natarajanii on dead wood of Prosopis juliflora, Fulvifomes subazonatus on trunk of Azadirachta indica, Macrolepiota bharadwajii on moist soil near the forest, Narcissea delicata on decaying elephant dung, Paramyrothecium indicum on living leaves of Hibiscus hispidissimus, Trichoglossum syamviswanathii on moist soil near the base of a bamboo plantation. Iran, Vacuiphoma astragalicola from stem canker of Astragalus sarcocolla. Malaysia, Neoeriomycopsis fissistigmae (incl. Neoeriomycopsidaceae fam. nov.) on leaf spots on flower Fissistigma sp. Namibia, Exophiala lichenicola lichenicolous on Acarospora cf. luederitzensis. Netherlands, Entoloma occultatum on soil, Extremus caricis on dead leaves of Carex sp., Inocybe pseudomytiliodora on loamy soil. Norway, Inocybe guldeniae on calcareous soil, Inocybe rupestroides on gravelly soil. Pakistan, Hymenagaricus brunneodiscus on soil. Philippines, Ophiocordyceps philippinensis parasitic on Asilus sp. Poland, Hawksworthiomyces ciconiae isolated from Ciconia ciconia nest, Plectosphaerella vigrensis from leaf spots on Impatiens noli-tangere, Xenoramularia epitaxicola from sooty mould community on Taxus baccata. Portugal, Inocybe dagamae on clay soil. Saudi Arabia, Diaporthe jazanensis on branches of Coffea arabica. South Africa, Alternaria moraeae on dead leaves of Moraea sp., Bonitomyces buffels-kloofinus (incl. Bonitomyces gen. nov.) on dead twigs of unknown tree, Constrictochalara koukolii on living leaves of Itea rhamnoides colonised by a Meliola sp., Cylindromonium lichenophilum on Parmelina tiliacea, Gamszarella buffelskloofina (incl. Gamszarella gen. nov.) on dead insect, Isthmosporiella africana (incl. Isthmosporiella gen. nov.) on dead twigs of unknown tree, Nothoeucasphaeria buffelskloofina (incl. Nothoeucasphaeria gen. nov.), on dead twigs of unknown tree, Nothomicrothyrium beaucarneae (incl. Nothomicrothyrium gen. nov.) on dead leaves of Beaucarnea stricta, Paramycosphaerella proteae on living leaves of Protea caffra, Querciphoma foliicola on leaf litter, Rachicladosporium conostomii on dead twigs of Conostomium natalense var. glabrum, Rhamphoriopsis synnematosa on dead twig of unknown tree, Waltergamsia mpumalanga on dead leaves of unknown tree. Spain, Amanita fulvogrisea on limestone soil, in mixed forest, Amanita herculis in open Quercus forest, Vuilleminia beltraniae on Cistus symphytifolius. Sweden, Pachyella pulchella on decaying wood on sand-silt riverbank. Thailand, Deniquelata cassiae on dead stem of Cassia fistula, Stomiopeltis thailandica on dead twigs of Magnolia champaca. Ukraine, Circinaria podoliana on natural limestone outcrops, Neonematogonum carpinicola (incl. Neonematogonum gen. nov.) on dead branches of Carpinus betulus. USA, Exophiala wilsonii water from cooling tower, Hygrophorus aesculeticola on soil in mixed forest, and Neocelosporium aereum from air in a house attic. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Costa MM, Kandemir H, et al. 2023. Fungal Planet description sheets: 1550-1613. Persoonia 51: 280-417. doi: 10.3767/persoonia.2023.51.08.
RESUMEN
BACKGROUND: Based on excellent outcomes from high-volume centres, laparoscopic liver resection is increasingly being adopted into nationwide practice which typically includes low-medium volume centres. It is unknown how the use and outcome of laparoscopic liver resection compare between high-volume centres and low-medium volume centres. This study aimed to compare use and outcome of laparoscopic liver resection in three leading European high-volume centres and nationwide practice in the Netherlands. METHOD: An international, retrospective multicentre cohort study including data from three European high-volume centres (Oslo, Southampton and Milan) and all 20 centres in the Netherlands performing laparoscopic liver resection (low-medium volume practice) from January 2011 to December 2016. A high-volume centre is defined as a centre performing >50 laparoscopic liver resections per year. Patients were retrospectively stratified into low, moderate- and high-risk Southampton difficulty score groups. RESULTS: A total of 2425 patients were included (1540 high-volume; 885 low-medium volume). The median annual proportion of laparoscopic liver resection was 42.9 per cent in high-volume centres and 7.2 per cent in low-medium volume centres. Patients in the high-volume centres had a lower conversion rate (7.4 versus 13.1 per cent; P < 0.001) with less intraoperative incidents (9.3 versus 14.6 per cent; P = 0.002) as compared to low-medium volume centres. Whereas postoperative morbidity and mortality rates were similar in the two groups, a lower reintervention rate (5.1 versus 7.2 per cent; P = 0.034) and a shorter postoperative hospital stay (3 versus 5 days; P < 0.001) were observed in the high-volume centres as compared to the low-medium volume centres. In each Southampton difficulty score group, the conversion rate was lower and hospital stay shorter in high-volume centres. The rate of intraoperative incidents did not differ in the low-risk group, whilst in the moderate-risk and high-risk groups this rate was lower in high-volume centres (absolute difference 6.7 and 14.2 per cent; all P < 0.004). CONCLUSION: High-volume expert centres had a sixfold higher use of laparoscopic liver resection, less conversions, and shorter hospital stay, as compared to a nationwide low-medium volume practice. Stratification into Southampton difficulty score risk groups identified some differences but largely outcomes appeared better for high-volume centres in each risk group.
Asunto(s)
Carcinoma Hepatocelular/cirugía , Hepatectomía/métodos , Hospitales de Alto Volumen/estadística & datos numéricos , Laparoscopía/métodos , Neoplasias Hepáticas/cirugía , Complicaciones Posoperatorias/epidemiología , Puntaje de Propensión , Anciano , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND: Abdominal computed tomography (CT) is the standard imaging method for patients with suspected colorectal liver metastases (CRLM) in the diagnostic workup for surgery or thermal ablation. Diffusion-weighted and gadoxetic-acid-enhanced magnetic resonance imaging (MRI) of the liver is increasingly used to improve the detection rate and characterization of liver lesions. MRI is superior in detection and characterization of CRLM as compared to CT. However, it is unknown how MRI actually impacts patient management. The primary aim of the CAMINO study is to evaluate whether MRI has sufficient clinical added value to be routinely added to CT in the staging of CRLM. The secondary objective is to identify subgroups who benefit the most from additional MRI. METHODS: In this international multicentre prospective incremental diagnostic accuracy study, 298 patients with primary or recurrent CRLM scheduled for curative liver resection or thermal ablation based on CT staging will be enrolled from 17 centres across the Netherlands, Belgium, Norway, and Italy. All study participants will undergo CT and diffusion-weighted and gadoxetic-acid enhanced MRI prior to local therapy. The local multidisciplinary team will provide two local therapy plans: first, based on CT-staging and second, based on both CT and MRI. The primary outcome measure is the proportion of clinically significant CRLM (CS-CRLM) detected by MRI not visible on CT. CS-CRLM are defined as liver lesions leading to a change in local therapeutical management. If MRI detects new CRLM in segments which would have been resected in the original operative plan, these are not considered CS-CRLM. It is hypothesized that MRI will lead to the detection of CS-CRLM in ≥10% of patients which is considered the minimal clinically important difference. Furthermore, a prediction model will be developed using multivariable logistic regression modelling to evaluate the predictive value of patient, tumor and procedural variables on finding CS-CRLM on MRI. DISCUSSION: The CAMINO study will clarify the clinical added value of MRI to CT in patients with CRLM scheduled for local therapy. This study will provide the evidence required for the implementation of additional MRI in the routine work-up of patients with primary and recurrent CRLM for local therapy. TRIAL REGISTRATION: The CAMINO study was registered in the Netherlands National Trial Register under number NL8039 on September 20th 2019.
Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Imagen Multimodal , Tomografía Computarizada por Rayos X , Adulto , Medios de Contraste/administración & dosificación , Gadolinio DTPA/administración & dosificación , Humanos , Neoplasias Hepáticas/cirugía , Estudios ProspectivosRESUMEN
BACKGROUND: Evidence for an association between hospital volume and outcomes for liver surgery is abundant. The current Dutch guideline requires a minimum volume of 20 annual procedures per centre. The aim of this study was to investigate the association between hospital volume and postoperative outcomes using data from the nationwide Dutch Hepato Biliary Audit. METHODS: This was a nationwide study in the Netherlands. All liver resections reported in the Dutch Hepato Biliary Audit between 2014 and 2017 were included. Annual centre volume was calculated and classified in categories of 20 procedures per year. Main outcomes were major morbidity (Clavien-Dindo grade IIIA or higher) and 30-day or in-hospital mortality. RESULTS: A total of 5590 liver resections were done across 34 centres with a median annual centre volume of 35 (i.q.r. 20-69) procedures. Overall major morbidity and mortality rates were 11·2 and 2·0 per cent respectively. The mortality rate was 1·9 per cent after resection for colorectal liver metastases (CRLMs), 1·2 per cent for non-CRLMs, 0·4 per cent for benign tumours, 4·9 per cent for hepatocellular carcinoma and 10·3 per cent for biliary tumours. Higher-volume centres performed more major liver resections, and more resections for hepatocellular carcinoma and biliary cancer. There was no association between hospital volume and either major morbidity or mortality in multivariable analysis, after adjustment for known risk factors for adverse events. CONCLUSION: Hospital volume and postoperative outcomes were not associated.
ANTECEDENTES: La asociación entre el volumen hospitalario y los resultados de la cirugía hepática no está clara. Según la recomendación actual de las guías holandesas se requiere un volumen mínimo de 20 procedimientos anuales por centro. El objetivo de este estudio fue analizar la asociación entre el volumen hospitalario con los resultados postoperatorios en la auditoría hepatobiliar obligatoria holandesa a nivel nacional. MÉTODOS: Se realizó un estudio a nivel nacional en los Países Bajos. Se incluyeron todas las resecciones hepáticas registradas en la auditoría hepatobiliar holandesa entre 2014 y 2017. El volumen anual del centro se calculó y se clasificó en categorías de 20 procedimientos por año. Los objetivos principales fueron la morbilidad de mayor grado (Clavien-Dindo grado IIIA o superior) y la mortalidad hospitalaria o la mortalidad a los 30 días. RESULTADOS: Se realizaron un total de 5.590 resecciones en 34 centros con una mediana (rango intercuartílico) de volumen anual de 35 procedimientos (20-69). La tasa global de morbilidad mayor fue del 11% y la mortalidad del 2%. La mortalidad fue de 1,9% después de la resección por metástasis hepáticas colorrectales (colorectal liver metastases, CRLM), 1,2% para no CRLM, 0,4% para tumores benignos, 4,9% para carcinoma hepatocelular, y 10,3% para tumores biliares. Los centros de mayor volumen realizaron más resecciones hepáticas mayores y más resecciones por carcinoma hepatocelular y cáncer biliar. En el análisis multivariable después de ajustar por factores de riesgo conocidos de eventos adversos, no se observó ninguna asociación entre el volumen hospitalario y la morbilidad o mortalidad mayor. CONCLUSIÓN: No hubo asociación entre el volumen hospitalario y los resultados postoperatorios de la cirugía hepática en los Países Bajos.
Asunto(s)
Hepatectomía , Hospitales/estadística & datos numéricos , Anciano , Carcinoma Hepatocelular/cirugía , Femenino , Hepatectomía/efectos adversos , Hepatectomía/mortalidad , Hepatectomía/estadística & datos numéricos , Humanos , Hígado/cirugía , Neoplasias Hepáticas/cirugía , Masculino , Análisis Multivariante , Países Bajos/epidemiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Factores de Riesgo , Encuestas y Cuestionarios , Resultado del TratamientoRESUMEN
BACKGROUND: Recurrences are reported in 70% of all patients after resection of colorectal liver metastases (CRLM), in which half are confined to the liver. Adjuvant hepatic arterial infusion pump (HAIP) chemotherapy aims to reduce the risk of intrahepatic recurrence. A large retrospective propensity score analysis demonstrated that HAIP chemotherapy is particularly effective in patients with low-risk oncological features. The aim of this randomized controlled trial (RCT) --the PUMP trial-- is to investigate the efficacy of adjuvant HAIP chemotherapy in low-risk patients with resectable CRLM. METHODS: This is an open label multicenter RCT. A total of 230 patients with resectable CRLM without extrahepatic disease will be included. Only patients with a clinical risk score (CRS) of 0 to 2 are eligible, meaning: patients are allowed to have no more than two out of five poor prognostic factors (disease-free interval less than 12 months, node-positive colorectal cancer, more than 1 CRLM, largest CRLM more than 5 cm in diameter, serum Carcinoembryonic Antigen above 200 µg/L). Patients randomized to arm A undergo complete resection of CRLM without any adjuvant treatment, which is the standard of care in the Netherlands. Patients in arm B receive an implantable pump at the time of CRLM resection and start adjuvant HAIP chemotherapy 4-12 weeks after surgery, with 6 cycles of floxuridine scheduled. The primary endpoint is progression-free survival (PFS). Secondary endpoints include overall survival, hepatic PFS, safety, quality of life, and cost-effectiveness. Pharmacokinetics of intra-arterial administration of floxuridine will be investigated as well as predictive biomarkers for the efficacy of HAIP chemotherapy. In a side study, the accuracy of CT angiography will be compared to radionuclide scintigraphy to detect extrahepatic perfusion. We hypothesize that adjuvant HAIP chemotherapy leads to improved survival, improved quality of life, and a reduction of costs, compared to resection alone. DISCUSSION: If this PUMP trial demonstrates that adjuvant HAIP chemotherapy improves survival in low-risk patients, this treatment approach may be implemented in the standard of care of patients with resected CRLM since adjuvant systemic chemotherapy alone has not improved survival. TRIAL REGISTRATION: The PUMP trial is registered in the Netherlands Trial Register (NTR), number: 7493 . Date of registration September 23, 2018.
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Antimetabolitos Antineoplásicos/administración & dosificación , Neoplasias Colorrectales/patología , Floxuridina/administración & dosificación , Hepatectomía , Neoplasias Hepáticas/terapia , Recurrencia Local de Neoplasia/prevención & control , Adulto , Quimioterapia Adyuvante/instrumentación , Quimioterapia Adyuvante/métodos , Ensayos Clínicos Fase III como Asunto , Neoplasias Colorrectales/mortalidad , Humanos , Bombas de Infusión Implantables , Infusiones Intraarteriales/instrumentación , Infusiones Intraarteriales/métodos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Estudios Multicéntricos como Asunto , Países Bajos , Supervivencia sin Progresión , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: Anastomotic leak after rectal surgery is reported in 9% (range 3-28%) of patients. The aim of our study was to evaluate the effectiveness of endosponge therapy for anastomotic. Endpoints were the rate of restored continuity and the functional bowel outcome after anastomotic leakage. METHODS: This was a multicenter retrospective observational cohort study. All patients with symptomatic anastomotic leakage after rectal surgery who had endosponge therapy between January 2012 and August 2017 were included. Functional bowel outcome was measured using the low anterior resection syndrome (LARS) score system. RESULTS: Twenty patients were included. Eighteen patients had low anterior resection (90%) for rectal cancer. A diverting ileostomy was performed at primary surgical intervention in 14 patients (70%). Fourteen patients (70%) were treated with neoadjuvant (chemo-)radiotherapy. The median time between primary surgical intervention and first endosponge placement was 21 (5-537) days. The median number of endosponge changes was 9 (2-28). The success rate of the endosponge treatment was 88% and the restored gastrointestinal continuity rate was 73%. A chronic sinus occurred in three patients (15%). All patients developed LARS, of which 77% reported major LARS. CONCLUSIONS: Endosponge therapy is an effective treatment for the closure of presacral cavities with high success rate and leading to restored gastrointestinal continuity in 73%. However, despite endosponge therapy many patients develop major LARS.
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Absceso/cirugía , Fuga Anastomótica/cirugía , Endoscopía Gastrointestinal/instrumentación , Ileostomía/efectos adversos , Complicaciones Posoperatorias/cirugía , Tapones Quirúrgicos de Gaza , Absceso/etiología , Anciano , Fuga Anastomótica/etiología , Endoscopía Gastrointestinal/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Proctectomía/efectos adversos , Neoplasias del Recto/cirugía , Recto/cirugía , Estudios Retrospectivos , Síndrome , Resultado del TratamientoRESUMEN
AIM: As a result of their extent and complexity, pelvic wounds after surgery for anorectal malignancy often require a multidisciplinary approach to accomplish closure. This report describes a successful reconstruction using the lotus petal perforator flap. METHOD: This flap is based on perforators of the internal pudendal artery and was partially depithelialized for plugging the defect. RESULTS: Wound healing was achieved after 12 days. CONCLUSION: The lotus petal flap is a relatively simple and successful choice for reconstruction of an extended chronic presacral defect after radiotherapy and rectal cancer resection.
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Adenocarcinoma/cirugía , Colectomía , Colgajo Perforante , Perineo/cirugía , Procedimientos de Cirugía Plástica/métodos , Neoplasias del Recto/cirugía , Recto del Abdomen/trasplante , Adenocarcinoma/diagnóstico , Adenocarcinoma/radioterapia , Anciano , Biopsia , Estudios de Seguimiento , Humanos , Masculino , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/radioterapia , Cicatrización de HeridasRESUMEN
BACKGROUND: In 2013, the nationwide Dutch Hepato Biliary Audit (DHBA) was initiated. The aim of this study was to evaluate changes in indications for and outcomes of liver surgery in the last decade. METHODS: This nationwide study included all patients who underwent liver surgery for four indications, including colorectal liver metastases (CRLM), hepatocellular carcinoma (HCC), and intrahepatic- and perihilar cholangiocarcinoma (iCCA - pCCA) between 2014 and 2022. Trends in postoperative outcomes were evaluated separately for each indication using multilevel multivariable logistic regression analyses. RESULTS: This study included 8057 procedures for CRLM, 838 for HCC, 290 for iCCA, and 300 for pCCA. Over time, these patients had higher risk profiles (more ASA-III patients and more comorbidities). Adjusted mortality decreased over time for CRLM, HCC and iCCA, respectively aOR 0.83, 95%CI 0.75-0.92, P < 0.001; aOR 0.86, 95%CI 0.75-0.99, P = 0.045; aOR 0.40, 95%CI 0.20-0.73, P < 0.001. Failure to rescue (FTR) also decreased for these groups, respectively aOR 0.84, 95%CI 0.76-0.93, P = 0.001; aOR 0.81, 95%CI 0.68-0.97, P = 0.024; aOR 0.29, 95%CI 0.08-0.84, P = 0.021). For iCCA severe complications (aOR 0.65 95%CI 0.43-0.99, P = 0.043) also decreased. No significant outcome differences were observed in pCCA. The number of centres performing liver resections decreased from 26 to 22 between 2014 and 2022, while median annual volumes did not change (40-49, P = 0.66). CONCLUSION: Over time, postoperative mortality and FTR decreased after liver surgery, despite treating higher-risk patients. The DHBA continues its focus on providing feedback and benchmark results to further enhance outcomes.
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Carcinoma Hepatocelular , Neoplasias Colorrectales , Hepatectomía , Neoplasias Hepáticas , Humanos , Países Bajos/epidemiología , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/secundario , Masculino , Femenino , Persona de Mediana Edad , Anciano , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/mortalidad , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/patología , Colangiocarcinoma/cirugía , Colangiocarcinoma/patología , Neoplasias de los Conductos Biliares/cirugía , Neoplasias de los Conductos Biliares/patología , Fracaso de Rescate en Atención a la Salud , Complicaciones Posoperatorias/epidemiología , Auditoría Médica , Resultado del Tratamiento , Tumor de Klatskin/cirugía , Tumor de Klatskin/patología , Tumor de Klatskin/mortalidadRESUMEN
OBJECTIVE: Implantable electrodes, such as electrocorticography (ECoG) grids, are used to record brain activity in applications like brain computer interfaces. To improve the spatial sensitivity of ECoG grid recordings, electrode properties need to be better understood. Therefore, the goal of this study is to analyze the importance of including electrodes explicitly in volume conduction calculations. APPROACH: We investigated the influence of ECoG electrode properties on potentials in three geometries with three different electrode models. We performed our simulations with FEMfuns, a volume conduction modeling software toolbox based on the finite element method. MAIN RESULTS: The presence of the electrode alters the potential distribution by an amount that depends on its surface impedance, its distance from the source and the strength of the source. Our modeling results show that when ECoG electrodes are near the sources the potentials in the underlying tissue are more uniform than without electrodes. We show that the recorded potential can change up to a factor of 3, if no extended electrode model is used. In conclusion, when the distance between an electrode and the source is equal to or smaller than the size of the electrode, electrode effects cannot be disregarded. Furthermore, the potential distribution of the tissue under the electrode is affected up to depths equal to the radius of the electrode. SIGNIFICANCE: This paper shows the importance of explicitly including electrode properties in volume conduction models for accurately interpreting ECoG measurements.
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Interfaces Cerebro-Computador , Electrocorticografía , Electrodos , Electrodos Implantados , Programas InformáticosRESUMEN
Applications such as brain computer interfaces require recordings of relevant neuronal population activity with high precision, for example, with electrocorticography (ECoG) grids. In order to achieve this, both the placement of the electrode grid on the cortex and the electrode properties, such as the electrode size and material, need to be optimized. For this purpose, it is essential to have a reliable tool that is able to simulate the extracellular potential, i.e., to solve the so-called ECoG forward problem, and to incorporate the properties of the electrodes explicitly in the model. In this study, this need is addressed by introducing the first open-source pipeline, FEMfuns (finite element method for useful neuroscience simulations), that allows neuroscientists to solve the forward problem in a variety of different geometrical domains, including different types of source models and electrode properties, such as resistive and capacitive materials. FEMfuns is based on the finite element method (FEM) implemented in FEniCS and includes the geometry tessellation, several electrode-electrolyte implementations and adaptive refinement options. The Python code of the pipeline is available under the GNU General Public License version 3 at https://github.com/meronvermaas/FEMfuns . We tested our pipeline with several geometries and source configurations such as a dipolar source in a multi-layer sphere model and a five-compartment realistically-shaped head model. Furthermore, we describe the main scripts in the pipeline, illustrating its flexible and versatile use. Provided with a sufficiently fine tessellation, the numerical solution of the forward problem approximates the analytical solution. Furthermore, we show dispersive material and interface effects in line with previous literature. Our results indicate substantial capacitive and dispersive effects due to the electrode-electrolyte interface when using stimulating electrodes. The results demonstrate that the pipeline presented in this paper is an accurate and flexible tool to simulate signals generated on electrode grids by the spatiotemporal electrical activity patterns produced by sources and thereby allows the user to optimize grids for brain computer interfaces including exploration of alternative electrode materials/properties.
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Electrocorticografía/métodos , Análisis de Elementos Finitos , Modelos Teóricos , Corteza Cerebral , Electrodos , HumanosRESUMEN
BACKGROUND: The results of resection of locally advanced and recurrent rectal cancers, including sacral resection, were analysed critically. METHODS: Between 1987 and 2007, 353 patients with locally advanced or recurrent rectal cancer, all treated in a tertiary referral centre, were identified from a prospective database. Twenty-five patients (eight primary and 17 recurrent tumours) underwent en bloc sacral resection. RESULTS: A mid-sacral resection was carried out in 12 patients (level S3) and a low sacral resection in 13 (level S4/S5). Nineteen patients had an R0, four an R1 and two an R2 resection. There was no postoperative mortality. Median follow-up was 32 months. Incomplete resection had an independent negative influence on local control (5-year local recurrence rate 42 versus 0 per cent in those with and without incomplete resection; P < 0.001). The 5-year overall survival rate was 30 per cent. Five patients with recurrent tumour had pathological invasion into the sacral bone and none survived beyond 1 year. CONCLUSION: Abdominosacral resection can be performed in patients with locally advanced and recurrent rectal cancer. Patients who cannot undergo a complete resection or have clear evidence of cortical invasion have a poor prognosis.
Asunto(s)
Adenocarcinoma/cirugía , Recurrencia Local de Neoplasia/cirugía , Neoplasias del Recto/cirugía , Sacro/cirugía , Neoplasias de la Columna Vertebral/cirugía , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/mortalidad , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Estudios Prospectivos , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Neoplasias de la Columna Vertebral/patología , Tomografía Computarizada por Rayos XRESUMEN
INTRODUCTION: Complete resection is the most important prognostic factor in surgery for pelvic tumors. In locally advanced and recurrent pelvic malignancies, radical margins are sometimes difficult to obtain because of close relation to or growth in adjacent organs/structures. Total pelvic exenteration (TPE) is an exenterative operation for these advanced tumors and involves en bloc resection of the rectum, bladder, and internal genital organs (prostate/seminal vesicles or uterus, ovaries and/or vagina). METHODS: Between 1994 and 2008, a TPE was performed in 69 patients with pelvic cancer; 48 with rectal cancer (32 primary and 16 recurrent), 14 with cervical cancer (1 primary and 13 recurrent), 5 with sarcoma (3 primary and 2 recurrent), 1 with primary vaginal, and 1 with recurrent endometrial carcinoma. Ten patients were treated with neoadjuvant chemotherapy and 66 patients with preoperative radiotherapy to induce down-staging. Eighteen patients received IORT because of an incomplete or marginal complete resection. RESULTS: The median follow-up was 43 (range, 1-196) months. Median duration of surgery was 448 (range, 300-670) minutes, median blood loss was 6,300 (range, 750-21,000) ml, and hospitalization was 17 (range, 4-65) days. Overall major and minor complication rates were 34% and 57%, respectively. The in-hospital mortality rate was 1%. A complete resection was possible in 75% of all patients, a microscopically incomplete resection (R1) in 16%, and a macroscopically incomplete resection (R2) in 9%. Five-year local control for primary locally advanced rectal cancer, recurrent rectal cancer, and cervical cancer was 89%, 38%, and 64%, respectively. Overall survival after 5 years for primary locally advanced rectal cancer, recurrent rectal cancer, and cervical cancer was 66%, 8%, and 45%. CONCLUSIONS: Total pelvic exenteration is accompanied with considerable morbidity, but good local control and acceptable overall survival justifies the use of this extensive surgical technique in most patients, especially patients with primary locally advanced rectal cancer and recurrent cervical cancer.
Asunto(s)
Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/mortalidad , Exenteración Pélvica/métodos , Neoplasias Pélvicas/mortalidad , Neoplasias Pélvicas/cirugía , Adulto , Anciano , Braquiterapia/métodos , Estudios de Cohortes , Supervivencia sin Enfermedad , Neoplasias Endometriales/mortalidad , Neoplasias Endometriales/patología , Neoplasias Endometriales/radioterapia , Neoplasias Endometriales/cirugía , Femenino , Mortalidad Hospitalaria/tendencias , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/radioterapia , Estadificación de Neoplasias , Exenteración Pélvica/efectos adversos , Neoplasias Pélvicas/patología , Neoplasias Pélvicas/radioterapia , Complicaciones Posoperatorias/mortalidad , Probabilidad , Pronóstico , Modelos de Riesgos Proporcionales , Calidad de Vida , Radioterapia Adyuvante , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Neoplasias del Recto/radioterapia , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Neoplasias del Cuello Uterino/mortalidad , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/cirugíaRESUMEN
AIMS: To report the role of total pelvic exenteration in a series of locally advanced and recurrent rectal cancers. METHODS: In the period 1994-2004, TPE was performed in 35 of 296 patients with primary locally advanced and recurrent rectal cancer treated in the Daniel den Hoed Cancer Center; 23 of 176 with primary locally advanced and 12 of 120 with recurrent rectal cancer. All but one patient received pre-operative External Beam Radiation Therapy (EBRT). After 1997, Intra Operative Radiotherapy (IORT) was performed in case of a resection margin less than 2 mm. RESULTS: Overall major complication rates were not significantly different between patients with primary and recurrent rectal cancer (26% vs. 50%, p=0.94). The hospital mortality rate was 3%. The 5-year local control and overall survival of patients with primary locally advanced rectal cancer were 88% and 52%, respectively. In patients with recurrent rectal cancer 3-year local control and survival rates were 60% and 32%, respectively. An incomplete resection, preoperative pain and advanced Wanebo stage for recurrent cancer were negative prognostic factors for both local control and overall survival. CONCLUSION: TPE in primary locally advanced rectal cancer enables good local control and acceptable overall survival, thereby justifying the use of the procedure. Patients with recurrent rectal cancer showed a high rate of major complications, a high distant metastasis rate, and a poor overall survival.
Asunto(s)
Exenteración Pélvica/métodos , Neoplasias del Recto/cirugía , Adulto , Anciano , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/radioterapia , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Complicaciones Posoperatorias , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias del Recto/patología , Neoplasias del Recto/radioterapia , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
INTRODUCTION: After publication of the results of the Dutch TME-trial preoperative radiotherapy followed by TME-surgery was introduced in July 2001 in the region of the comprehensive cancer centre Rotterdam as standard treatment for rectal cancer. The aim of this study is to identify the compliance to a new standardized treatment protocol i.e. the introduction of preoperative radiotherapy and to analyze the results of rectal cancer treatment in the Cancer Centre Rotterdam Region. PATIENTS AND METHODS: A total of 521 patients with adenocarcinoma of the rectum were included in the period from 2001 to 2003. All patients were treated with curative intent. RESULTS: There was a significant increase of preoperative radiotherapy for patients with a tumour in the lower two-third of the rectum (21% versus 69%, p<0.001). Peri-operative mortality rate was 2.7% and overall anastomotic leakage rate was 10.3%. There was a significant increase in the occurrence of anastomotic leakage in end-to-end anastomoses (p<0.0001). Most anastomotic leakages occurred when patients were operated in between 4 and 8 days after the end of radiotherapy. Several aspects such as continence for urine and faeces and sexual functions were poorly registered. The total number of lymph nodes registered in pathology reports was low. The rate of reported circumferential margins increased from 37% to 70% after feedback to the regional pathology working group. CONCLUSION: The regional quality of rectal cancer surgery is conform preset quality-demands. There was a significant increase in the percentage preoperative radiotherapy, but still about 25% of patients who qualified for radiotherapy did not receive radiation. Pathology reports improved during registration, which illustrates the importance of registration to assess and improve quality of rectal cancer treatment.
Asunto(s)
Adenocarcinoma/radioterapia , Cuidados Preoperatorios/métodos , Neoplasias del Recto/radioterapia , Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Proctocolectomía Restauradora/métodos , Radioterapia Adyuvante , Neoplasias del Recto/mortalidad , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Resultado del TratamientoRESUMEN
INTRODUCTION: The aim of this study is to describe our experience with reconstruction of pelvic defects after surgery for previously irradiated malignancies using a gracilis muscle flap transposition. PATIENTS AND METHODS: Between 1993 and 2002, 25 patients were treated by primary (n=7) or secondary reconstruction (n=18) using a gracilis muscle transfer. All patients were previously irradiated with a median dosage of 50 Gy. RESULTS: Direct reconstruction following resection of the tumour was accompanied with minor complications in three patients and without major complications. Median time to complete healing of the donor site and perineal defect was 11 and 46 days, respectively. Reconstruction of persistent perineal infections resulted in minor complications at the donor site (n=3) and at the perineal wound (n=11). Three patients experienced a major complication. Median time to complete healing of the donor site and perineal defect was, respectively, 17 and 190 days. Necrosis of the gracilis muscle flaps was not observed. CONCLUSION: Direct reconstruction with a gracilis transfer resulted in primary wound healing with low morbidity, hereby preventing potentially disabling persistent defects. After debridement of persistent wounds, indirect reconstruction with gracilis muscle resulted in the majority of patients in healing of the defects with acceptable morbidity.