Implementation of robotic rectal cancer surgery: a cross-sectional nationwide study.

AIM: An increasing number of centers have implemented a robotic surgical program for rectal cancer. Several randomized controls trials have shown similar oncological and postoperative outcomes compared to standard laparoscopic resections. While introducing a robot rectal resection program seems safe, there are no data regarding implementation on a nationwide scale. Since 2018 robot resections are separately registered in the mandatory Dutch Colorectal Audit. The present study aims to evaluate the trend in the implementation of robotic resections (RR) for rectal cancer relative to laparoscopic rectal resections (LRR) in the Netherlands between 2018 and 2020 and to compare the differences in outcomes between the operative approaches. METHODS: Patients with rectal cancer who underwent surgical resection between 2018 and 2020 were selected from the Dutch Colorectal Audit. The data included patient characteristics, disease characteristics, surgical procedure details, postoperative outcomes. The outcomes included any complication within 90 days after surgery; data were categorized according to surgical approach. RESULTS: Between 2018 and 2020, 6330 patients were included in the analyses. 1146 patients underwent a RR (18%), 3312 patients a LRR (51%), 526 (8%) an open rectal resection, 641 a TaTME (10%), and 705 had a local resection (11%). The proportion of males and distal tumors was higher in the RR compared to the LRR. Over time, the proportion of robotic procedures increased from 15% (95% confidence intervals (CI) 13-16%) in 2018 to 22% (95% CI 20-24%) in 2020. Conversion rate was lower in the robotic group [4% (95% CI 3-5%) versus 7% (95% CI 6-8%)]. Anastomotic leakage rate was similar with 16%. Defunctioning ileostomies were more common in the RR group [42% (95% CI 38-46%) versus 29% (95% CI 26-31%)]. CONCLUSION: Rectal resections are increasingly being performed through a robot-assisted approach in the Netherlands. The proportion of males and low rectal cancers was higher in RR compared to LRR. Overall outcomes were comparable, while conversion rate was lower in RR, the proportion of defunctioning ileostomies was higher compared to LRR.

Value of routine intraoperative frozen sections of proximal bile duct margins in perihilar cholangiocarcinoma, a retrospective multicenter and matched case-control study.

BACKGROUND: Currently, the potential benefits of additional resection after positive proximal intraoperative frozen sections (IFS) in perihilar cholangiocarcinoma (pCCA) on residual disease and oncological outcome remain uncertain. Therefore, the aim of this study is to investigate the number of R0 resections after additional resection of a positive proximal IFS and the influence of additional resections on overall survival (OS) in patients with pCCA. MATERIALS AND METHODS: A retrospective, multicenter, matched case-control study was performed, including patients undergoing resection for pCCA between 2000 and 2019 at three tertiary centers. Primary outcome was the number of achieved 'additional' R0 resections. Secondary outcomes were OS, recurrence, severe morbidity and mortality. RESULTS: Forty-four out of 328 patients undergoing resection for pCCA had a positive proximal IFS. An additional resection was performed in 35 out of 44 (79.5%) patients, which was negative in 24 (68.6%) patients. Nevertheless, seven out of these 24 patients were eventually classified as R1 resection due to other positive resection margins. Therefore, 17 (48.6%) patients could be classified as "true" R0 resection after additional resection. Ninety-day mortality after R1 resections was high (25%) and strongly influenced OS. After correction for 90-day mortality, median OS after negative additional resection was 33 months (95%CI:29.5-36.5) compared to 30 months (95%CI:24.4-35.6) after initial R1 (P = 0.875) and 46 months (95%CI:32.7-59.3) after initial R0 (P = 0.348). CONCLUSION: There were only 17 patients (out of a total of 328 patients) that potentially benefitted from routine IFS. Additional resection for a positive IFS leading to R0 resection was not associated with improved long-term survival.

Treatment of metachronous colorectal cancer metastases in the Netherlands: A population-based study.

BACKGROUND: This study aimed to describe the treatment of metachronous colorectal cancer metastases in a recent population-based cohort. METHOD: Patients with stage I-III colorectal cancer (CRC), diagnosed between January 1st and June 30th, 2015 who were surgically treated with curative intent were selected from the Netherlands Cancer Registry. Follow-up was at least 3 years after diagnosis of the primary tumour. Treatment of metachronous metastases was categorized into local treatment, systemic treatment, and best supportive care. Overall survival was estimated using Kaplan-Meier method. RESULTS: Out of 5412 patients, 782 (14%) developed metachronous metastases, of whom 393 (50%) underwent local treatment (LT) with or without systemic therapy, 30% of patients underwent only systemic therapy (ST) and 19% only best supportive care (BSC). The most common metastatic site was the liver (51%) followed by lungs (33%) and peritoneum (22%). LT rates were 69%, 66%, and 44% for liver-only, lung-only and, peritoneal-only metastases respectively. Patients receiving LT and ST were significantly younger than patients receiving LT alone, while patients receiving BSC were significantly older than the other groups (p < 0.001). Patients with liver-only or lung-only metastases had a 3-year OS of 50.2% (43.3-56.7 95% CI) and 61.5% (50.7-70.6 95% CI) respectively. Patients with peritoneal-only disease had a lower 3-year OS, 18.1% (10.1-28.0 95% CI). CONCLUSION: Patients with metastases confined to the liver and lung have the highest rates of local treatment for metachronous metastatic colorectal cancer. The number of patients who underwent local treatment is higher than reported in previous Dutch and international studies.

Changes in rectal cancer treatment after the introduction of a national screening program; Increasing use of less invasive strategies within a national cohort.

AIM: Organ preserving treatment strategies and the introduction of a colorectal cancer-screening program have likely influenced the resection rates of rectal cancer. The aim of this study is to assess the influence of these developments on rectal cancer treatment and resection rates in the Netherlands. METHODS: Patients diagnosed with non-metastatic rectal cancer between 2013 and 2018, were selected from the Netherlands Cancer Registry. The distribution of surgical and neo-adjuvant treatment and resection rates were analyzed and compared over time. RESULTS: Between 2013 and 2018 22640 patients were diagnosed with non-metastatic rectal cancer. The incidence of early stage (cT1) disease increased from 141 (4%) in 2013 to 448 (12%) in 2018. The use of neoadjuvant radiotherapy and chemo-radiotherapy dropped from 39% to 21% and 34%-25%, respectively. A decrease in surgical resection rates (including TEM) was observed from 85% to 73%. The proportion of patients who underwent endoscopic resections increased from 3% to 10%. The decrease in surgical resection rates was larger in patients treated with neo-adjuvant chemo-radiotherapy. CONCLUSION: An increase in stage I disease is noted after the introduction of the screening program. Surgical resection rates for rectal cancer have fallen over time. Endoscopic resections due to more early-stage disease probably accounts for a large part of this decline. Furthermore, a watch and wait approach after neo-adjuvant chemo-radiotherapy may play an important role as well.

Surgery for rectal cancer: Differences in resection rates among hospitals in the Netherlands.

AIM: Numerous quality improvement initiatives for rectal cancer surgery have focused on textbook outcome parameters. In these studies, resection rate and patients who did not undergo surgery are not included, but these parameters might help to evaluate the surgical care for rectal cancer. The aim of this study is to assess the variation of non-metastatic rectal cancer resection rates among hospitals and its effect on patient outcomes. METHODS: All patients diagnosed with non-metastatic rectal cancer between 2013 and 2018 were selected from the Netherlands Cancer Registry. Hospitals were categorized in quartiles according to resection rates. A multivariable logistic analysis was performed to determine variation in resection rate between these quartiles using a logistic regression analysis to correct for confounders. The association between resection rates and survival was analyzed using Kaplan-Meier method and Cox-regression analysis. RESULTS: A total of 22,530 patients were included in the analysis. Resection rates varied from 68 to 89% between hospitals. After multivariable analysis, resection rate remained significantly different among the quartiles when correcting for several factors (odds ratio (95%Confidence-interval) 1.71 (1.56-1.88), 2.42 (2.19-2.67), and 4.04 (3.61-4.53) for increasing resection rate quartiles, in reference to the lowest quartile). A higher resection rate was associated with better overall survival, in multivariable analysis this survival benefit could no longer be identified. CONCLUSION: There is a substantial variation in resection rates for rectal cancer among hospitals in the Netherlands with an impact on overall survival. This may be a relevant issue when analyzing the overall quality of rectal cancer care.

Effect of structured use of preoperative portal vein embolization on outcomes after liver resection of perihilar cholangiocarcinoma.

BACKGROUND: Portal vein embolization (PVE) is performed to reduce the risk of liver failure and subsequent mortality after major liver resection. Although a cut-off value of 2·7 per cent per min per m2 has been used with hepatobiliary scintigraphy (HBS) for future remnant liver function (FRLF), patients with perihilar cholangiocarcinoma (PHC) potentially benefit from an additional cut-off of 8·5 per cent/min (not corrected for body surface area). Since January 2016 a more liberal approach to PVE has been adopted, including this additional cut-off for HBS of 8·5 per cent/min. The aim of this study was to assess the effect of this approach on liver failure and mortality. METHODS: This was a single-centre retrospective study in which consecutive patients undergoing liver resection under suspicion of PHC in 2000-2015 were compared with patients treated in 2016-2019, after implementation of the more liberal approach. Primary outcomes were postoperative liver failure (International Study Group of Liver Surgery grade B/C) and 90-day mortality. RESULTS: Some 191 patients with PHC underwent liver resection. PVE was performed in 6·4 per cent (9 of 141) of the patients treated in 2000-2015 and in 32 per cent (16 of 50) of those treated in 2016-2019. The 90-day mortality rate decreased from 16·3 per cent (23 of 141) to 2 per cent (1 of 50) (P = 0·009), together with a decrease in the rate of liver failure from 19·9 per cent (28 of 141) to 4 per cent (2 of 50) (P = 0·008). In 2016-2019, 24 patients had a FRLF greater than 8·5 per cent/min and no liver failure or death occurred, suggesting that 8·5 per cent/min is a reliable cut-off for patients with suspected PHC. CONCLUSION: The major decrease in liver failure and mortality rates in recent years and the simultaneous increased use of PVE suggests an important role for PVE in reducing adverse outcomes after surgery for PHC.

ANTECEDENTES: La embolización de la vena porta (portal vein embolization, PVE) se realiza para reducir el riesgo de insuficiencia hepática y de mortalidad asociada después de una resección hepática mayor. Aunque con la gammagrafía hepato-biliar (hepato-biliary scintigraphy, HBS) se ha utilizado un punto de corte de 2,7%/min/m2 para la función hepática remanente futura (future remnant liver function, FRLF), los pacientes con colangiocarcinoma perihilar (perihilar cholangiocarcinoma, PHC) se beneficiarían potencialmente de un punto de corte adicional de 8,5%/min (no corregido para el área de superficie corporal). Desde enero de 2016, se adoptó un enfoque más liberal para la PVE, incluyendo este punto de corte adicional para la HBS de 8,5%/min. El objetivo de este estudio fue evaluar el efecto de este enfoque sobre la insuficiencia hepática y la mortalidad. MÉTODOS: Se trata de un estudio retrospectivo de un solo centro, en el que los pacientes consecutivos sometidos a resección hepática por sospecha de PHC entre 2000-2016 se compararon con los pacientes tratados entre 2016-2019, después de la implementación de un enfoque más liberal. Los objetivos primarios fueron la insuficiencia hepática postoperatoria (ISGLS grado B/C) y la mortalidad a los 90 días. RESULTADOS: Un total de 191 pacientes con PHC se sometieron a resección hepática. Se realizó PVE en el 6% (9/141) de los pacientes antes de 2016 y en el 32% (16/50) de los pacientes después de 2016. La mortalidad disminuyó del 16% (23/141) al 2% (1/50) (P = 0,009), junto con una disminución de la insuficiencia hepática del 20% (28/141) al 4% (2/50) (P = 0,008). Después de 2016, 20 pacientes tuvieron un FRLF > 8,5%/min y no se produjo insuficiencia hepática o mortalidad, lo que sugiere que el 8,5%/min es un punto de corte fiable para los pacientes con sospecha de PHC. CONCLUSIÓN: La disminución marcada de la insuficiencia hepática y de la mortalidad en los últimos años y el aumento simultáneo del uso de la PVE, sugiere que la PVE ha jugado un importante papel en el descenso de los resultados adversos después de la cirugía para el PHC.

Volume-outcome relationship of liver surgery: a nationwide analysis.

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.

Effect of obeticholic acid on liver regeneration following portal vein embolization in an experimental model.

BACKGROUND: The bile salt-activated transcription factor farnesoid X receptor (FXR) is a key mediator of proliferative bile salt signalling, which is assumed to play a role in the early phase of compensatory liver growth. The aim of this study was to evaluate the effect of a potent FXR agonist (obeticholic acid, OCA) on liver growth following portal vein embolization (PVE). METHODS: Rabbits were allocated to receive daily oral gavage with OCA (10 mg/kg) or vehicle (control group) starting 7 days before PVE (n = 18 per group), and continued until 7 days after PVE. PVE of the cranial liver lobes was performed using polyvinyl alcohol particles and coils on day 0. Caudal liver volume (CLV) was analysed by CT volumetry on days -7, -1, +3 and +7. Liver function was determined by measuring mebrofenin uptake using hepatobiliary scintigraphy. Additional parameters analysed were plasma aminotransferase levels, and histological scoring of haematoxylin and eosin- and Ki-67-stained liver sections. RESULTS: Three days after PVE of the cranial lobes, the increase in CLV was 2·2-fold greater in the OCA group than in controls (mean(s.d.) 56·1(20·3) versus 26·1(15·4) per cent respectively; P < 0·001). This increase remained greater 7 days after PVE (+1·5-fold; P = 0·020). The increase in caudal liver function at day +3 was greater in OCA-treated animals (+1·2-fold; P = 0·017). The number of Ki-67-positive hepatocytes was 1·6-fold higher in OCA-treated animals 3 days after PVE (P = 0·045). Plasma aminotransferase levels and histology did not differ significantly between groups. CONCLUSION: OCA accelerated liver regeneration after PVE in a rabbit model. OCA treatment might increase the efficacy of PVE and, thereby, resectability. Surgical relevance Liver failure is the most feared complication after liver surgery, with no effective treatment options. Liver regeneration is essential to avoid liver failure, and recently bile acid signalling was implicated in the initiation of liver regeneration through the nuclear bile acid receptor farnesoid X receptor (FXR). In this study, the potent FXR agonist obeticholic acid accelerated liver regeneration following portal vein embolization in a rabbit model, in terms of liver volume, liver function and proliferation. Obeticholic acid treatment could enhance the efficacy of portal vein embolization, thereby increasing resectability, and could reduce the interval to surgery. In addition, obeticholic acid might have a place in the prevention of liver failure after liver surgery.

Hepatic vascular inflow occlusion is associated with reduced disease free survival following resection of colorectal liver metastases.

BACKGROUND: Hepatic vascular inflow occlusion (VIO) can be applied during resection of colorectal liver metastases (CRLM) to control intra-operative blood loss, but has been linked to accelerated growth of micrometastases in experimental models. This study aimed to investigate the effects of hepatic VIO on disease-free and overall survival (DFS and OS) in patients following resection for CRLM. METHODS: All patients who underwent liver resection for CRLM between January 2006 and September 2015 at our center were analyzed. Hepatic VIO was performed if deemed indicated by the operating surgeon and severe ischemia was defined as ≥20 min continuous or ≥45 min cumulative intermittent VIO. Cox regression analysis was performed to identify predictive factors for DFS and OS. RESULTS: A total of 208 patients underwent liver resection for CRLM. VIO was performed in 64 procedures (31%), and fulfilled the definition of severe ischemia in 40 patients. Patients with severe ischemia had inferior DFS (5-year DFS 32% vs. 11%, P < 0.01), and inferior OS (5-year OS 37% vs. 64%, P < 0.01). At multivariate analysis, a high clinical risk score (Hazard ratio (HR) 1.60 (1.08-2.36)) and severe ischemia (HR 1.89 (1.21-2.97)) were independent predictors of worse DFS. Severe ischemia was not an independent predictor of OS. CONCLUSION: The present cohort study suggests that prolonged hepatic VIO during liver resection for CRLM was associated with reduced DFS. A patient-tailored approach seems advisable although larger studies should confirm these findings.

Use of an absorbable embolization material for reversible portal vein embolization in an experimental model.

BACKGROUND: Portal vein embolization (PVE) is used to increase future remnant liver size in patients requiring major hepatic resection. PVE using permanent embolization, however, predisposes to complications and excludes the use of PVE in living donor liver transplantation. In the present study, an absorbable embolization material containing fibrin glue and different concentrations of the fibrinolysis inhibitor aprotinin was used in an experimental animal model. METHODS: PVE of the cranial liver lobes was performed in 30 New Zealand White rabbits, which were divided into five groups, fibrin glue + 1000, 700, 500, 300 or 150 kunits/ml aprotinin, and were compared with a previous series of permanent embolization using the same experimental set-up. Caudal liver lobe hypertrophy was determined by CT volumetry, and portal recanalization was identified on contrast-enhanced CT images. Animals were killed after 7 or 42 days, and the results were compared with those of permanent embolization. RESULTS: PVE using fibrin glue with aprotinin as embolic material was effective, with 500 kunits/ml providing the optimal hypertrophic response. Lower concentrations of aprotinin (150 and 300 kunits/ml) led to reduced hypertrophy owing to early recanalization of the embolized segments. The regeneration rate over the first 3 days was higher in the group with 500 kunits/ml aprotinin than in the groups with 300 or 150 kunits/ml or permanent embolization. In the 500-kunits/ml group, four of five animals showed recanalization 42 days after embolization, with minimal histological changes in the cranial lobes following recanalization. CONCLUSION: Fibrin glue combined with 500 kunits/ml aprotinin resulted in reversible PVE in 80 per cent of animals, with a hypertrophy response comparable to that achieved with permanent embolization material. Surgical relevance Portal vein embolization (PVE) is used to increase future remnant liver volume in patients scheduled for major liver resection who have insufficient future remnant liver size to perform a safe resection. The current standard is PVE with permanent embolization materials, which renders patients found to have unresectable disease prone to complications owing to the permanently deportalized liver segments. Absorbable embolization might prevent the PVE-associated morbidity and lower the threshold for its application. In this study, PVE using fibrin glue and aprotinin resulted in an adequate hypertrophy response with 80 per cent recanalization after 42 days. Considering the minor histological changes following recanalization of embolized segments and potentially preserved function, reversible PVE might also be applied in living donor liver transplantation.