Resectability of bilobar liver tumours after simultaneous portal and hepatic vein embolization versus portal vein embolization alone: meta-analysis

BACKGROUND

Many patients with bi-lobar liver tumours are not eligible for liver resection due to an insufficient future liver remnant (FLR). To reduce the risk of posthepatectomy liver failure and the primary cause of death, regenerative procedures intent to increase the FLR before surgery. The aim of this systematic review is to provide an overview of the available literature and outcomes on the effectiveness of simultaneous portal and hepatic vein embolization (PVE/HVE) versus portal vein embolization (PVE) alone.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Embase up to September 2022. The primary outcome was resectability and the secondary outcome was the FLR volume increase.

RESULTS

Eight studies comparing PVE/HVE with PVE and six retrospective PVE/HVE case series were included. Pooled resectability within the comparative studies was 75 per cent in the PVE group (n = 252) versus 87 per cent in the PVE/HVE group (n = 166, OR 1.92 (95% c.i., 1.13-3.25)) favouring PVE/HVE (P = 0.015). After PVE, FLR hypertrophy between 12 per cent and 48 per cent (after a median of 21-30 days) was observed, whereas growth between 36 per cent and 67 per cent was reported after PVE/HVE (after a median of 17-31 days). In the comparative studies, 90-day primary cause of death was similar between groups (2.5 per cent after PVE versus 2.2 per cent after PVE/HVE), but a higher 90-day primary cause of death was reported in single-arm PVE/HVE cohort studies (6.9 per cent, 12 of 175 patients).

CONCLUSION

Based on moderate/weak evidence, PVE/HVE seems to increase resectability of bi-lobar liver tumours with a comparable safety profile. Additionally, PVE/HVE resulted in faster and more pronounced hypertrophy compared with PVE alone.

Prophylactic abdominal drainage or no drainage after distal pancreatectomy (PANDORINA): a binational multicenter randomized controlled trial

BACKGROUND

Prophylactic abdominal drainage is current standard practice after distal pancreatectomy (DP), with the aim to divert pancreatic fluid in case of a postoperative pancreatic fistula (POPF) aimed to prevent further complications as bleeding. Whereas POPF after pancreatoduodenectomy, by definition, involves infection due to anastomotic dehiscence, a POPF after DP is essentially sterile since the bowel is not opened and no anastomoses are created. Routine drainage after DP could potentially be omitted and this could even be beneficial because of the hypothetical prevention of drain-induced infections (Fisher, Surgery 52:205-22, 2018). Abdominal drainage, moreover, should only be performed if it provides additional safety or comfort to the patient. In clinical practice, drains cause clear discomfort. One multicenter randomized controlled trial confirmed the safety of omitting abdominal drainage but did not stratify patients according to their risk of POPF and did not describe a standardized strategy for pancreatic transection. Therefore, a large pragmatic multicenter randomized controlled trial is required, with prespecified POPF risk groups and a homogeneous method of stump closure. The objective of the PANDORINA trial is to evaluate the non-inferiority of omitting routine intra-abdominal drainage after DP on postoperative morbidity (Clavien-Dindo score ≥ 3), and, secondarily, POPF grade B/C.

METHODS/DESIGN

Binational multicenter randomized controlled non-inferiority trial, stratifying patients to high and low risk for POPF grade B/C and incorporating a standardized strategy for pancreatic transection. Two groups of 141 patients (282 in total) undergoing elective DP (either open or minimally invasive, with or without splenectomy). Primary outcome is postoperative rate of morbidity (Clavien-Dindo score ≥ 3), and the most relevant secondary outcome is grade B/C POPF. Other secondary outcomes include surgical reintervention, percutaneous catheter drainage, endoscopic catheter drainage, abdominal collections (not requiring drainage), wound infection, delayed gastric emptying, postpancreatectomy hemorrhage as defined by the international study group for pancreatic surgery (ISGPS) (Wente et al., Surgery 142:20-5, 2007), length of stay (LOS), readmission within 90 days, in-hospital mortality, and 90-day mortality.

DISCUSSION

PANDORINA is the first binational, multicenter, randomized controlled non-inferiority trial with the primary objective to evaluate the hypothesis that omitting prophylactic abdominal drainage after DP does not worsen the risk of postoperative severe complications (Wente etal., Surgery 142:20-5, 2007; Bassi et al., Surgery 161:584-91, 2017). Most of the published studies on drain placement after pancreatectomy focus on both pancreatoduodenectomy and DP, but these two entities present are associated with different complications and therefore deserve separate evaluation (McMillan et al., Surgery 159:1013-22, 2016; Pratt et al., J Gastrointest Surg 10:1264-78, 2006). The PANDORINA trial is innovative since it takes the preoperative risk on POPF into account based on the D-FRS and it warrants homogenous stump closing by using the same graded compression technique and same stapling device (de Pastena et al., Ann Surg 2022; Asbun and Stauffer, Surg Endosc 25:2643-9, 2011).

Dragon 1 Protocol Manuscript: Training, Accreditation, Implementation and Safety Evaluation of Portal and Hepatic Vein Embolization (PVE/HVE) to Accelerate Future Liver Remnant (FLR) Hypertrophy

STUDY PURPOSE

The DRAGON 1 trial aims to assess training, implementation, safety and feasibility of combined portal- and hepatic-vein embolization (PVE/HVE) to accelerate future liver remnant (FLR) hypertrophy in patients with borderline resectable colorectal cancer liver metastases.

METHODS

The DRAGON 1 trial is a worldwide multicenter prospective single arm trial. The primary endpoint is a composite of the safety of PVE/HVE, 90-day mortality, and one year accrual monitoring of each participating center. Secondary endpoints include: feasibility of resection, the used PVE and HVE techniques, FLR-hypertrophy, liver function (subset of centers), overall survival, and disease-free survival. All complications after the PVE/HVE procedure are documented. Liver volumes will be measured at week 1 and if applicable at week 3 and 6 after PVE/HVE and follow-up visits will be held at 1, 3, 6, and 12 months after the resection.

RESULTS

Not applicable.

CONCLUSION

DRAGON 1 is a prospective trial to assess the safety and feasibility of PVE/HVE. Participating study centers will be trained, and procedures standardized using Work Instructions (WI) to prepare for the DRAGON 2 randomized controlled trial. Outcomes should reveal the accrual potential of centers, safety profile of combined PVE/HVE and the effect of FLR-hypertrophy induction by PVE/HVE in patients with CRLM and a small FLR.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04272931 (February 17, 2020). Toestingonline.nl: NL71535.068.19 (September 20, 2019).

Clinical added value of MRI to CT in patients scheduled for local therapy of colorectal liver metastases (CAMINO): study protocol for an international multicentre prospective diagnostic accuracy study

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.

Comparing practice and outcome of laparoscopic liver resection between high-volume expert centres and nationwide low-to-medium volume centres

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.

Robotic versus laparoscopic distal pancreatectomy: multicentre analysis

BACKGROUND

The role of minimally invasive distal pancreatectomy is still unclear, and whether robotic distal pancreatectomy (RDP) offers benefits over laparoscopic distal pancreatectomy (LDP) is unknown because large multicentre studies are lacking. This study compared perioperative outcomes between RDP and LDP.

METHODS

A multicentre international propensity score-matched study included patients who underwent RDP or LDP for any indication in 21 European centres from six countries that performed at least 15 distal pancreatectomies annually (January 2011 to June 2019). Propensity score matching was based on preoperative characteristics in a 1 : 1 ratio. The primary outcome was the major morbidity rate (Clavien-Dindo grade IIIa or above).

RESULTS

A total of 1551 patients (407 RDP and 1144 LDP) were included in the study. Some 402 patients who had RDP were matched with 402 who underwent LDP. After matching, there was no difference between RDP and LDP groups in rates of major morbidity (14.2 versus 16.5 per cent respectively; P = 0.378), postoperative pancreatic fistula grade B/C (24.6 versus 26.5 per cent; P = 0.543) or 90-day mortality (0.5 versus 1.3 per cent; P = 0.268). RDP was associated with a longer duration of surgery than LDP (median 285 (i.q.r. 225-350) versus 240 (195-300) min respectively; P < 0.001), lower conversion rate (6.7 versus 15.2 per cent; P < 0.001), higher spleen preservation rate (81.4 versus 62.9 per cent; P = 0.001), longer hospital stay (median 8.5 (i.q.r. 7-12) versus 7 (6-10) days; P < 0.001) and lower readmission rate (11.0 versus 18.2 per cent; P = 0.004).

CONCLUSION

The major morbidity rate was comparable between RDP and LDP. RDP was associated with improved rates of conversion, spleen preservation and readmission, to the detriment of longer duration of surgery and hospital stay.

Risk of conversion to open surgery during robotic and laparoscopic pancreatoduodenectomy and effect on outcomes: international propensity score-matched comparison study

BACKGROUND

Minimally invasive pancreatoduodenectomy (MIPD) is increasingly being performed because of perceived patient benefits. Whether conversion of MIPD to open pancreatoduodenectomy worsens outcome, and which risk factors are associated with conversion, is unclear.

METHODS

This was a post hoc analysis of a European multicentre retrospective cohort study of patients undergoing MIPD (2012-2017) in ten medium-volume (10-19 MIPDs annually) and four high-volume (at least 20 MIPDs annually) centres. Propensity score matching (1 : 1) was used to compare outcomes of converted and non-converted MIPD procedures. Multivariable logistic regression analysis was performed to identify risk factors for conversion, with results presented as odds ratios (ORs) with 95 per cent confidence intervals (c.i).

RESULTS

Overall, 65 of 709 MIPDs were converted (9.2 per cent) and the overall 30-day mortality rate was 3.8 per cent. Risk factors for conversion were tumour size larger than 40 mm (OR 2.7, 95 per cent c.i.1.0 to 6.8; P = 0.041), pancreatobiliary tumours (OR 2.2, 1.0 to 4.8; P = 0.039), age at least 75 years (OR 2.0, 1.0 to 4.1; P = 0.043), and laparoscopic pancreatoduodenectomy (OR 5.2, 2.5 to 10.7; P < 0.001). Medium-volume centres had a higher risk of conversion than high-volume centres (15.2 versus 4.1 per cent, P < 0.001; OR 4.1, 2.3 to 7.4, P < 0.001). After propensity score matching (56 converted MIPDs and 56 completed MIPDs) including risk factors, rates of complications with a Clavien-Dindo grade of III or higher (32 versus 34 per cent; P = 0.841) and 30-day mortality (12 versus 6 per cent; P = 0.274) did not differ between converted and non-converted MIPDs.

CONCLUSION

Risk factors for conversion during MIPD include age, large tumour size, tumour location, laparoscopic approach, and surgery in medium-volume centres. Although conversion during MIPD itself was not associated with worse outcomes, the outcome in these patients was poor in general which should be taken into account during patient selection for MIPD.

Robotic Pancreatoduodenectomy: Patient Selection, Volume Criteria, and Training Programs

INTRODUCTION

There has been a rapid development in minimally invasive pancreas surgery in recent years. The most recent innovation is robotic pancreatoduodenectomy. Several studies have suggested benefits as compared to the open or laparoscopic approach. This review provides an overview of studies concerning patient selection, volume criteria, and training programs for robotic pancreatoduodenectomy and identified knowledge gaps regarding barriers for safe implementation of robotic pancreatoduodenectomy.

MATERIALS AND METHODS

A Pubmed search was conducted concerning patient selection, volume criteria, and training programs in robotic pancreatoduodenectomy.

RESULTS

A total of 20 studies were included. No contraindications were found in patient selection for robotic pancreatoduodenectomy. The consensus and the Miami guidelines advice is a minimum annual volume of 20 robotic pancreatoduodenectomy procedures per center, per year. One training program was identified which describes superior outcomes after the training program and shortening of the learning curve in robotic pancreatoduodenectomy.

CONCLUSION

Robotic pancreatoduodenectomy is safe and feasable for all indications when performed by specifically trained surgeons working in centers who can maintain a minimum volume of 20 robotic pancreatoduodenectomy procedures per year. Large proficiency-based training program for robotic pancreatoduodenectomy seem essential to facilitate a safe implementation and future research on robotic pancreatoduodenectomy.

Laparoscopic versus open extended radical left pancreatectomy for pancreatic ductal adenocarcinoma: an international propensity-score matched study

BACKGROUND

A radical left pancreatectomy in patients with pancreatic ductal adenocarcinoma (PDAC) may require extended, multivisceral resections. The role of a laparoscopic approach in extended radical left pancreatectomy (ERLP) is unclear since comparative studies are lacking. The aim of this study was to compare outcomes after laparoscopic vs open ERLP in patients with PDAC.

METHODS

An international multicenter propensity-score matched study including patients who underwent either laparoscopic or open ERLP (L-ERLP; O-ERLP) for PDAC was performed (2007-2015). The ISGPS definition for extended resection was used. Primary outcomes were overall survival, margin negative rate (R0), and lymph node retrieval.

RESULTS

Between 2007 and 2015, 320 patients underwent ERLP in 34 centers from 12 countries (65 L-ERLP vs. 255 O-ERLP). After propensity-score matching, 44 L-ERLP could be matched to 44 O-ERLP. In the matched cohort, the conversion rate in L-ERLP group was 35%. The L-ERLP R0 resection rate (matched cohort) was comparable to O-ERLP (67% vs 48%; P = 0.063) but the lymph node yield was lower for L-ERLP than O-ERLP (median 11 vs 19, P = 0.023). L-ERLP was associated with less delayed gastric emptying (0% vs 16%, P = 0.006) and shorter hospital stay (median 9 vs 13 days, P = 0.005), as compared to O-ERLP. Outcomes were comparable for additional organ resections, vascular resections (besides splenic vessels), Clavien-Dindo grade ≥ III complications, or 90-day mortality (2% vs 2%, P = 0.973). The median overall survival was comparable between both groups (19 vs 20 months, P = 0.571). Conversion did not worsen outcomes in L-ERLP.

CONCLUSION

The laparoscopic approach may be used safely in selected patients requiring ERLP for PDAC, since morbidity, mortality, and overall survival seem comparable, as compared to O-ERLP. L-ERLP is associated with a high conversion rate and reduced lymph node yield but also with less delayed gastric emptying and a shorter hospital stay, as compared to O-ERLP.

Predicting poor outcome in patients with suspected COVID-19 presenting to the Emergency Department (COVERED) - Development, internal and external validation of a prediction model

BACKGROUND

A recent systematic review recommends against the use of any of the current COVID-19 prediction models in clinical practice. To enable clinicians to appropriately profile and treat suspected COVID-19 patients at the emergency department (ED), externally validated models that predict poor outcome are desperately needed.

OBJECTIVE

Our aims were to identify predictors of poor outcome, defined as mortality or ICU admission within 30 days, in patients presenting to the ED with a clinical suspicion of COVID-19, and to develop and externally validate a prediction model for poor outcome.

METHODS

In this prospective, multi-center study, we enrolled suspected COVID-19 patients presenting at the EDs of two hospitals in the Netherlands. We used backward logistic regression to develop a prediction model. We used the area under the curve (AUC), Brier score and pseudo-R2 to assess model performance. The model was externally validated in an Italian cohort.

RESULTS

We included 1193 patients between March 12 and May 27 2020, of whom 196 (16.4%) had a poor outcome. We identified 10 predictors of poor outcome: current malignancy (OR 2.774; 95%CI 1.682-4.576), systolic blood pressure (OR 0.981; 95%CI 0.964-0.998), heart rate (OR 1.001; 95%CI 0.97-1.028), respiratory rate (OR 1.078; 95%CI 1.046-1.111), oxygen saturation (OR 0.899; 95%CI 0.850-0.952), body temperature (OR 0.505; 95%CI 0.359-0.710), serum urea (OR 1.404; 95%CI 1.198-1.645), C-reactive protein (OR 1.013; 95%CI 1.001-1.024), lactate dehydrogenase (OR 1.007; 95%CI 1.002-1.013) and SARS-CoV-2 PCR result (OR 2.456; 95%CI 1.526-3.953). The AUC was 0.86 (95%CI 0.83-0.89), with a Brier score of 0.32 and, and R2 of 0.41. The AUC in the external validation in 500 patients was 0.70 (95%CI 0.65-0.75).

CONCLUSION

The COVERED risk score showed excellent discriminatory ability, also in an external validation. It may aid clinical decision making, and improve triage at the ED in health care environments with high patient throughputs.

Risk factors and outcomes of conversion in minimally invasive distal pancreatectomy: a systematic review

Purpose

The reported conversion rates for minimally invasive distal pancreatectomy (MIDP) range widely from 2 to 38%. The identification of risk factors for conversion may help surgeons during preoperative planning and patient counseling. Moreover, the impact of conversion on outcomes of MIDP is unknown.

Methods

A systematic review was conducted as part of the 2019 Miami International Evidence-Based Guidelines on Minimally Invasive Pancreas Resection (IG-MIPR). The PubMed, Cochrane, and Embase databases were searched for studies concerning conversion to open surgery in MIDP.

Results

Of the 828 studies screened, eight met the eligibility criteria, resulting in a combined dataset including 2592 patients after MIDP. The overall conversion rate was 17.1% (range 13.0–32.7%) with heterogeneity between studies associated with the definition of conversion adopted. Only one study divided conversion into elective and emergency conversion. The main indications for conversion were vascular involvement (23.7%), concern for oncological radicality (21.9%), and bleeding (18.9%). The reported risk factors for conversion included a malignancy as an indication for surgery, the proximity of the tumor to vascular structures in preoperative imaging, higher BMI or visceral fat, and multi-organ resection or extended resection. Contrasting results were seen in terms of blood loss and length of stay in comparing converted MIDP and completed MIDP patients.

Conclusion

The identified risk factors for conversion from this study can be used for patient selection and counseling. Surgeon experience should be considered when contemplating MIDP for a complex patient. Future studies should divide conversion into elective and emergency conversion.

The role of older age and obesity in minimally invasive and open pancreatic surgery: A systematic review and meta-analysis

BACKGROUND/OBJECTIVES

The aim of this study was to assess the impact of older age (≥70 years) and obesity (BMI ≥30) on surgical outcomes of minimally invasive pancreatic resections (MIPR). Subsequently, open pancreatic resections or MIPR were compared for elderly and/or obese patients.

METHODS

A systematic review was conducted as part of the 2019 Miami International Evidence-Based Guidelines on MIPR (IG-MIPR). Study quality assessment was according to The Scottish Intercollegiate Guidelines Network (SIGN). A meta-analysis was performed to assess the impact of MIPR or open pancreatic resections in elderly patients.

RESULTS

After screening 682 studies, 13 observational studies with 4629 patients were included. Elderly patients undergoing laparoscopic distal pancreatectomy (LDP) had less blood loss (117 mL, p < 0.001) and a shorter hospital stay (3.5 days p < 0.001) than elderly patients undergoing open distal pancreatectomy (ODP). Postoperative pancreatic fistula (POPF) B/C, major complication and reoperation rate were not significantly different in elderly patients undergoing either laparoscopic or open pancreatoduodenectomy (OPD). One study compared robot PD with OPD in obese patients, indicating that patients with robotic surgery had less blood loss (mean 250 ml vs 500 ml, p = 0.001), shorter operative time (mean 381 min vs 428 min, p = 0.003), and lower rate of POPF B/C (13% vs 28%, p = 0.039).

CONCLUSION

The current available limited evidence does not suggest that MIPR is contraindicated in elderly or obese patients. Additionally, outcomes in MIPR are equal or more beneficial compared to the open approach when applied in these patient groups.

Robotic Versus Conventional Laparoscopic Liver Resections: A Systematic Review and Meta-Analysis

BACKGROUND

Theoretical advantages of robotic surgery compared to conventional laparoscopic surgery include improved instrument dexterity, 3D visualization, and better ergonomics. This systematic review and meta-analysis aimed to determine advantages of robotic surgery over laparoscopic surgery in patients undergoing liver resections.

METHOD

A systematic literature search was conducted for studies comparing robotic assisted or totally laparoscopic liver resection. Meta-analysis of intraoperative (operative time, blood loss, transfusion rate, conversion rate), oncological (R0 resection rates), and postoperative (bile leak, surgical site infection, pulmonary complications, 30-day and 90-day mortality, length of stay, 90-day readmission and reoperation rates) outcomes was performed using a random effects model.

RESULT

Twenty-six non-randomized studies including 2630 patients (950 robotic and 1680 laparoscopic) were included, of which 20% had major robotic liver resection and 14% had major laparoscopic liver resection. Intraoperatively, robotic liver resection was associated with significantly less blood loss (mean: 286 vs 301 mL, p < 0.001) but longer operating time (mean: 281 vs 221 min, p < 0.001). There were no significant differences in conversion rates or transfusion rates between robotic liver resection and laparoscopic liver resection. Postoperatively, there were no significant differences in overall complications, bile leaks, and length of hospital stay between robotic liver resection and laparoscopic liver resection. However, robotic liver resection was associated with significantly lower readmission rates than laparoscopic liver resection (odds ratio: 0.43, p = 0.005).

CONCLUSION

Robotic liver resection appears to offer some advantages compared to conventional laparoscopic surgery, although both techniques appear equivalent. Importantly, the quality of evidence is generally limited to cohort studies and a high-quality randomized trial comparing both techniques is needed.

Predictors for Survival in an International Cohort of Patients Undergoing Distal Pancreatectomy for Pancreatic Ductal Adenocarcinoma

Background

Surgical factors, including resection of Gerota’s fascia, R0-resection, and lymph node yield, may be associated with survival after distal pancreatectomy (DP) for pancreatic ductal adenocarcinoma (PDAC), but evidence from large multicenter studies is lacking. This study aimed to identify predictors for overall survival after DP for PDAC, especially those related to surgical technique.

Patients and Methods

Data from an international retrospective cohort including patients from 11 European countries and the USA who underwent DP for PDAC (2007–2015) were analyzed. Cox proportional hazard analyses were performed and included Gerota’s fascia resection, R0 resection, lymph node ratio, extended resection, and a minimally invasive approach.

Results

Overall, 1200 patients from 34 centers with median follow-up of 15 months [interquartile range (IQR) 5–31 months] and median survival period of 30 months [95% confidence interval (CI), 27–33 months] were included. Gerota’s fascia resection [hazard ratio (HR) 0.74; p = 0.019], R0 resection (HR 0.70; p = 0.006), and decreased lymph node ratio (HR 0.28; p < 0.001) were associated with improved overall survival, whereas extended resection (HR 1.75; p < 0.001) was associated with worse overall survival. A minimally invasive approach did not improve survival as compared with an open approach (HR 1.14; p = 0.350). Adjuvant chemotherapy (HR 0.67; p = 0.003) was also associated with improved overall survival.

Conclusions

This international cohort identified Gerota’s fascia resection, R0 resection, and decreased lymph node ratio as factors associated with improved overall survival during DP for PDAC. Surgeons should strive for R0 resection and adequate lymphadenectomy and could also consider Gerota’s fascia resection in their routine surgical approach.

Electronic supplementary material

The online version of this article (10.1245/s10434-020-08658-5) contains supplementary material, which is available to authorized users.

Gemcitabine-based adjuvant chemotherapy in subtypes of ampullary adenocarcinoma: international propensity score-matched cohort study

BACKGROUND

Whether patients who undergo resection of ampullary adenocarcinoma have a survival benefit from adjuvant chemotherapy is currently unknown. The aim of this study was to compare survival between patients with and without adjuvant chemotherapy after resection of ampullary adenocarcinoma in a propensity score-matched analysis.

METHODS

An international multicentre cohort study was conducted, including patients who underwent pancreatoduodenectomy for ampullary adenocarcinoma between 2006 and 2017, in 13 centres in six countries. Propensity scores were used to match patients who received adjuvant chemotherapy with those who did not, in the entire cohort and in two subgroups (pancreatobiliary/mixed and intestinal subtypes). Survival was assessed using the Kaplan-Meier method and Cox regression analyses.

RESULTS

Overall, 1163 patients underwent pancreatoduodenectomy for ampullary adenocarcinoma. After excluding 187 patients, median survival in the remaining 976 patients was 67 (95 per cent c.i. 56 to 78) months. A total of 520 patients (53·3 per cent) received adjuvant chemotherapy. In a propensity score-matched cohort (194 patients in each group), survival was better among patients who received adjuvant chemotherapy than in those who did not (median survival not reached versus 60 months respectively; P = 0·051). A survival benefit was seen in patients with the pancreatobiliary/mixed subtype; median survival was not reached in patients receiving adjuvant chemotherapy and 32 months in the group without chemotherapy (P = 0·020). Patients with the intestinal subtype did not show any survival benefit from adjuvant chemotherapy.

CONCLUSION

Patients with resected ampullary adenocarcinoma may benefit from gemcitabine-based adjuvant chemotherapy, but this effect may be reserved for those with the pancreatobiliary and/or mixed subtype.

Multicentre observational cohort study of implementation and outcomes of laparoscopic distal pancreatectomy

BACKGROUND

Laparoscopic distal pancreatectomy (LDP) is increasingly being performed as an alternative to open surgery. Whether the implementation and corresponding learning curve of LDP have an impact on patient outcome is unknown. The aim was to investigate the temporal trends in practice across UK centres.

METHODS

This was a retrospective multicentre observational cohort study of LDP in 11 tertiary referral centres in the UK between 2006 and 2016. The learning curve was analysed by pooling data for the first 15 consecutive patients who had LDP and examining trends in surgical outcomes in subsequent patients.

RESULTS

In total, 570 patients underwent LDP, whereas 888 underwent open resection. For LDP the median duration of operation was 240 min, with 200 ml blood loss. The conversion rate was 12·1 per cent. Neuroendocrine tumours (26·7 per cent) and mucinous cystic neoplasms (19·7 per cent) were commonest indications. The proportion of LDPs increased from 24·4 per cent in 2006-2009 (P1) to 46·0 per cent in 2014-2016 (P3) (P < 0·001). LDP was increasingly performed for patients aged 70 years or more (16 per cent in P1 versus 34·4 per cent in P3; P = 0·002), pancreatic ductal adenocarcinoma (6 versus 19·1 per cent; P = 0·005) and advanced malignant tumours (27 versus 52 per cent; P = 0·016). With increasing experience, there was a trend for a decrease in blood transfusion rate (14·1 per cent for procedures 1-15 to 3·5 per cent for procedures 46-75; P = 0·008), ICU admissions (32·7 to 19·2 per cent; P = 0·021) and median duration of hospital stay (7 (i.q.r. 5-9) to 6 (4-7) days; P = 0·002). After 30 procedures, a decrease was noted in rates of both overall morbidity (57·7 versus 42·2 per cent for procedures 16-30 versus 46-75 respectively; P = 0·009) and severe morbidity (18·8 versus 9·7 per cent; P = 0·031).

CONCLUSION

LDP has increased as a treatment option for lesions of the distal pancreas as indications for the procedure have expanded. Perioperative outcomes improved with the number of procedures performed.

Multicentre analysis of the learning curve for laparoscopic liver resection of the posterosuperior segments

BACKGROUND

Laparoscopic liver resection demands expertise and a long learning curve. Resection of the posterosuperior segments is challenging, and there are no data on the learning curve. The aim of this study was to evaluate the learning curve for laparoscopic resection of the posterosuperior segments.

METHODS

A cumulative sum (CUSUM) analysis of the difficulty score for resection was undertaken using patient data from four specialized centres. Risk-adjusted CUSUM analysis of duration of operation, blood loss and conversions was performed, adjusting for the difficulty score of the procedures. A receiver operating characteristic (ROC) curve was used to identify the completion of the learning curve.

RESULTS

According to the CUSUM analysis of 464 patients, the learning curve showed an initial decrease in the difficulty score followed by an increase and, finally, stabilization. More patients with cirrhosis or previous surgery were operated in the latest phase of the learning curve. A smaller number of wedge resections and a larger number of anatomical resections were performed progressively. Dissection using a Cavitron ultrasonic surgical aspirator and the Pringle manoeuvre were used more frequently with time. Risk-adjusted CUSUM analysis showed a progressive decrease in operating time. Blood loss initially increased slightly, then stabilized and finally decreased over time. A similar trend was found for conversions. The learning curve was estimated to be 40 procedures for wedge and 65 for anatomical resections.

CONCLUSION

The learning curve for laparoscopic liver resection of the posterosuperior segments consists of a stepwise process, during which accurate patient selection is key.

Safety and efficacy of transarterial embolization of hepatocellular adenomas

BACKGROUND

Hepatocellular adenoma (HCA) larger than 5 cm in diameter has an increased risk of haemorrhage and malignant transformation, and is considered an indication for resection. As an alternative to resection, transarterial embolization (TAE) may play a role in prevention of complications of HCA, but its safety and efficacy are largely unknown. The aim of this study was to assess outcomes and postembolization effects of selective TAE in the management of HCA.

METHODS

This retrospective, multicentre cohort study included patients aged at least 18 years, diagnosed with HCA and treated with TAE. Patient characteristics, 30-day complications, tumour size before and after TAE, symptoms before and after TAE, and need for secondary interventions were analysed.

RESULTS

Overall, 59 patients with a median age of 33.5 years were included from six centres; 57 of the 59 patients were women. Median tumour size at time of TAE was 76 mm. Six of 59 patients (10 per cent) had a major complication (cyst formation or sepsis), which could be resolved with minimal therapy, but prolonged hospital stay. Thirty-four patients (58 per cent) were symptomatic at presentation. There were no significant differences in symptoms before TAE and symptoms evaluated in the short term (within 3 months) after TAE (P = 0·134). First follow-up imaging was performed a median of 5·5 months after TAE and showed a reduction in size to a median of 48 mm (P < 0·001).

CONCLUSION

TAE is safe, can lead to adequate size reduction of HCA and, offers an alternative to resection in selected patients.

Multicentre propensity score-matched study of laparoscopic versus open repeat liver resection for colorectal liver metastases

BACKGROUND

Repeat liver resection is often the best treatment option for patients with recurrent colorectal liver metastases (CRLM). Repeat resections can be complex, however, owing to adhesions and altered liver anatomy. It remains uncertain whether the advantages of a laparoscopic approach are upheld in this setting. The aim of this retrospective, propensity score-matched study was to compare the short-term outcome of laparoscopic (LRLR) and open (ORLR) repeat liver resection.

METHODS

A multicentre retrospective propensity score-matched study was performed including all patients who underwent LRLRs and ORLRs for CRLM performed in nine high-volume centres from seven European countries between 2000 and 2016. Patients were matched based on propensity scores in a 1 : 1 ratio. Propensity scores were calculated based on 12 preoperative variables, including the approach to, and extent of, the previous liver resection. Operative outcomes were compared using paired tests.

RESULTS

Overall, 425 repeat liver resections were included. Of 271 LRLRs, 105 were matched with an ORLR. Baseline characteristics were comparable after matching. LRLR was associated with a shorter duration of operation (median 200 (i.q.r. 123-273) versus 256 (199-320) min; P < 0·001), less intraoperative blood loss (200 (50-450) versus 300 (100-600) ml; P = 0·077) and a shorter postoperative hospital stay (5 (3-8) versus 6 (5-8) days; P = 0·028). Postoperative morbidity and mortality rates were similar after LRLR and ORLR.

CONCLUSION

LRLR for CRLM is feasible in selected patients and may offer advantages over an open approach.

Risk of malignancy in resected pancreatic mucinous cystic neoplasms

BACKGROUND

Pancreatic mucinous cystic neoplasms (MCNs) are rare mucin-producing cystic tumours defined by the presence of ovarian-type stroma. MCNs have a malignant potential and thus surgery is frequently performed. The aim of this cohort study was to define better the criteria for surgical resection in patients with MCN.

METHODS

This multicentre retrospective study included all resected MCNs between 2003 and 2015 in participating centres. Lesions without ovarian-type stroma were excluded. Patient characteristics, preoperative findings, histopathology findings and follow-up data were recorded.

RESULTS

The study included 211 patients; their median age was 53 (range 18-82) years, and 202 (95·7 per cent) were women. Median preoperative tumour size was 55 (range 12-230) mm. Thirty-four of the 211 (16·1 per cent) were malignant, and high-grade dysplasia (HGD) was found in a further 13 (6·2 per cent). One-third of MCNs in men were associated with invasive cancer, compared with 15·3 per cent in women. Five cases of malignant transformation occurred in MCNs smaller than 4 cm. All cases of malignancy or HGD were associated with symptoms or features of concern on preoperative cross-sectional imaging. In multivariable analysis, raised carbohydrate antigen 19-9 (odds ratio (OR) 10·54, 95 per cent c.i. 2·85 to 218·23; P < 0·001), tumour size (OR 4·23, 3·02 to 11·03; P = 0·001), mural nodules (OR 3·55, 1·31 to 20·55; P = 0·002) and weight loss (OR 3·40, 2·34 to 12·34; P = 0·034) were independent factors predictive of malignant transformation.

CONCLUSIONS

Small indeterminate MCNs with no symptoms or features of concern may safely be observed as they have a low risk of malignant transformation.

Vasoactive intestinal peptide induces proliferation of human hepatocytes

OBJECTIVES

Proliferation of hepatocytes in vitro can be stimulated by growth factors such as epidermal growth factor (EGF), but the role of vasoactive intestinal peptide (VIP) remains unclear. We have investigated the effect of VIP on maintenance and proliferation of human hepatocytes.

MATERIALS AND METHODS

Human hepatocytes were isolated from liver specimens obtained from patients undergoing liver surgery. Treatment with VIP or EGF was started 24 h after plating and continued for 3 or 5 d. DNA replication was investigated by Bromodeoxyuridine (BrdU) incorporation and cell viability detected by MTT assay. Cell lysate was analysed by western blotting and RT-PCR. Urea and albumin secretion into the culture supernatants were measured.

RESULTS

VIP increased DNA replication in hepatocytes in a dose-dependant manner, with a peak response at day 3 of treatment. VIP treatment was associated with an increase in mRNA expression of antigen identified by monoclonal antibody Ki-67 (MKI-67) and Histone Cluster 3 (H3) genes. Western blotting analysis showed that VIP can induce a PKA/B-Raf dependant phosphorylation of extracellular signal-regulated kinases (ERK). Although EGF can maintain hepatocyte functions up to day 5, no marked efffect was found with VIP.

CONCLUSIONS

VIP induces proliferation of human hepatocytes with little or no effect on hepatocyte differentiation. Further investigation of the role of VIP is required to determine if it may ultimately support therapeutic approaches of liver disease.

Development and validation of a difficulty score to predict intraoperative complications during laparoscopic liver resection

Background

Previous studies have demonstrated that patient, surgical, tumour and operative variables affect the complexity of laparoscopic liver resections. However, current difficulty scoring systems address only tumour factors. The aim of this study was to develop and validate a predictive model for the risk of intraoperative complications during laparoscopic liver resections.

Methods

The prospectively maintained databases of seven European tertiary referral liver centres were compiled. Data from two-thirds of the patients were used for development and one-third for validation of the model. Intraoperative complications were based on a modified Satava classification. Using the methodology of the Framingham Heart Study, developed to identify risk factors that contribute to the development of cardiovascular disease, factors found to predict intraoperative complications independently were assigned points, and grouped into low-, moderate-, high- and extremely high-risk groups based on the likelihood of intraoperative complications.

Results

A total of 2856 patients were included. Neoadjuvant chemotherapy, lesion type and size, classification of resection and previous open liver resection were found to be independent predictors of intraoperative complications. Patients with intraoperative complications had a longer duration of hospital stay (5 versus 4 days; P &lt; 0·001), higher complication rates (32·5 versus 15·5 per cent; P &lt; 0·001), and higher 30-day (3·0 versus 0·3 per cent; P &lt; 0·001) and 90-day (3·8 versus 0·8 per cent; P &lt; 0·001) mortality rates than those who did not. The model was able to predict intraoperative complications (area under the receiver operating characteristic (ROC) curve (AUC) 0·677, 95 per cent c.i. 0·647 to 0·706) as well as postoperative 90-day mortality (AUC 0·769, 0·681 to 0·858).

Conclusion

This comprehensive scoring system, based on patient, surgical and tumour factors, and developed and validated using a large multicentre European database, helped estimate the risk of intraoperative complications.

Proactive multi-modality treatment of Pancreatic Neuroendocrine Tumours (PNETs): Potential survival benefits

BACKGROUND/OBJECTIVES

Primary and metastatic pancreatic neuroendocrine tumours (PNET) can be treated with combination of surgery, locoregional and systemic therapy. Survival benefits from individual treatments have been well reported, however, the combined outcome from multimodal treatments are not well described in the literature. We report outcomes in a cohort of PNET patients treated with proactive, multimodality therapy.

METHODS

106 patients were identified from a single tertiary referral centre prospective database. Outcomes of treatment were studied, with the primary end point being death from any cause.

RESULTS

Median follow-up was 71 months and overall 5-year survival of 62%. In patients with stage I-III disease (51 patients) estimated 5-year survival was 90%. Median survival in patients with stage IV disease was 51 months with an estimated 5-year survival of 40% in this group. A total of 80 patients (75%) had surgery of which 16% suffered complications requiring intervention. There was no perioperative mortality.

CONCLUSIONS

This study demonstrates that proactive multimodal treatment is safe and may confer a survival benefit to patients in this cohort compared to historical data.

Hazardous parameters associated with natural radioactivity exposure from black sand

Black sand samples collected from Baltim beaches (Kafr El-Sheikh governorate) in Egypt on the Mediterranean Sea shore were analyzed radiometrically and evaluated using a nondestructive gamma ray spectroscopic techniques. The natural radionuclides of ²²⁶Ra, ²³²Th and ⁴⁰K in the black sand samples were identified and quantified. It is found that the activity concentrations for ²²⁶Ra, ²³²Th and ⁴⁰K in different eleven sites (S1S11) were found within the ranges of 28-322, 91-308 and 81-339 Bq/kg, respectively. Moreover, different radiological hazardous parameters (absorbed dose rate, annual effective dose equivalent, radium activity, annual gonadal dose equivalent and excess lifetime cancer risk) were calculated. The results show that these values are greater than the permissible values due to increasing the activity concentrations of the primordial radionuclides ²²⁶Ra, ²³²Th and ⁴⁰K. The dose rate for radiation emitted at 1 m from the surface of land was measured directly and the results shown that all sites emit radiation doses more than the international permissible value (57 nGy/h) especially at three sites which around 340 nGy/h. These values are important to establish baseline levels of this environmental radioactivity to detect any upcoming change for the local population and resorts people. The relatively high dose rate will be considered as a spa for the physical therapy such as treatment of some skin diseases and rheumatoid.

Impact of portal vein infiltration and type of venous reconstruction in surgery for borderline resectable pancreatic cancer

BACKGROUND

The International Study Group of Pancreatic Surgery (ISGPS) recommends operative exploration and resection of pancreatic cancers in the presence of reconstructable mesentericoportal axis involvement. However, there is no consensus on the ideal method of vascular reconstruction. The effect of depth of tumour invasion of the vessel wall on outcome is also unknown.

METHODS

This was a retrospective cohort study of pancreaticoduodenectomy with vein resection for T3 adenocarcinoma of the head of the pancreas across nine centres. Outcome measures were overall survival based on the impact of the depth of tumour infiltration of the vessel wall, and morbidity, in-hospital mortality and overall survival between types of venous reconstruction: primary closure, end-to-end anastomosis and interposition graft.

RESULTS

A total of 229 patients underwent portal vein resection; 129 (56·3 per cent) underwent primary closure, 64 (27·9 per cent) had an end-to-end anastomosis and 36 (15·7 per cent) an interposition graft. There was no difference in overall morbidity (26 (20·2 per cent), 14 (22 per cent) and 9 (25 per cent) respectively; P = 0·817) or in-hospital mortality (6 (4·7 per cent), 2 (3 per cent) and 2 (6 per cent); P = 0·826) between the three groups. One hundred and six patients (47·5 per cent) had histological evidence of vein involvement; 59 (26·5 per cent) had superficial invasion (tunica adventitia) and 47 (21·1 per cent) had deep invasion (tunica media or intima). Median survival was 18·8 months for patients who had primary closure, 27·6 months for those with an end-to-end anastomosis and 13·0 months among patients with an interposition graft. There was no significant difference in median survival between patients with superficial, deep or no histological vein involvement (20·8, 21·3 and 13·3 months respectively; P = 0·111). Venous tumour infiltration was not associated with decreased overall survival on multivariable analysis.

CONCLUSION

In this study, there was no difference in morbidity between the three modes of venous reconstruction, and overall survival was similar regardless of tumour infiltration of the vein.

Outcome after laparoscopic and open resections of posterosuperior segments of the liver

BACKGROUND

Laparoscopic resection of posterosuperior (PS) segments of the liver is hindered by limited visualization and curvilinear resection planes. The aim of this study was to compare outcomes after open and laparoscopic liver resections of PS segments.

METHODS

Patients who underwent minor open liver resection (OLR) and laparoscopic liver resection (LLR) between 2006 and 2014 were identified from the institutional databases of seven tertiary referral European hepatobiliary surgical units. Propensity score-matched analysis was used to match groups for known confounders. Perioperative outcomes including complications were assessed using the Dindo-Clavien classification, and the comprehensive complication index was calculated. Survival was analysed with the Kaplan-Meier method.

RESULTS

Some 170 patients underwent OLR and 148 had LLR. After propensity score-matched analysis, 86 patients remained in both groups. Overall postoperative complication rates were significantly higher after OLR compared with LLR: 28 versus 14 per cent respectively (P = 0·039). The mean(s.d.) comprehensive complication index was higher in the OLR group, although the difference was not statistically significant (26·7(16·6) versus 18·3(8·0) in the LLR group; P = 0·108). The mean(s.d.) duration of required analgesia and the median (range) duration of postoperative hospital stay were significantly shorter in the LLR group: 3·0(1·1) days versus 1·6(0·8) days in the OLR group (P < 0·001), and 6 (3-44) versus 4 (1-11) days (P < 0·001), respectively. The 3-year recurrence-free survival rates for patients with hepatocellular carcinoma (37 per cent for OLR versus 30 per cent for LLR; P = 0·534) and those with colorectal liver metastases (36 versus 36 per cent respectively; P = 0·440) were not significantly different between the groups.

CONCLUSION

LLR of tumours in PS segments is feasible in selected patients. LLR is associated with fewer complications and does not compromise survival compared with OLR.

Chemical distribution of hazardous natural radionuclides during monazite mineral processing

It is very important to calculate the radioactivity concentration for low-grade monazite ore (50%) and different other materials produced as results of chemical processing stages to avoid the risk to workers. Chemical processing of low-grade monazite pass through different stages, washing by hydrochloric acid and digested with sulfuric acid and influence of pH on the precipitation of rare earth elements has been studied. The radioactivity concentrations of ²³⁸U(²²⁶Ra) and ²³²Th as well as ⁴⁰K were calculated in crude low-grade ore and found to be 54,435 ± 3138, 442,105 ± 29,200 and 5841 ± 345 Bq/kg, respectively. These values are greatly higher than the exempt levels 25 Bq/kg. After chemical digestion of the ore, the results demonstrated that un-reacted material contains significant radioactivity reached to approximately 8, 13 and 23% for ²³⁸U, ²³²Th and ⁴⁰K, respectively. The results show that 60% of ²³²Th are located in the digested white slurry with small portions of ²³⁸U and ⁴⁰K. Most of ²³⁸U radioactivity is extracted in the green phosphoric acid which produced from conversion of P₂O₅ by H₂SO₄ into phosphoric acid. The average values of the Ra_eq for monazite ore, un-reacted black precipitate, white precipitate, brown precipitate and crystalline material samples were calculated and found to be 687,095 ± 44,921, 85,068 ± 5339, 388,381 ± 22,088, 313,046 ± 17,923 and 4531 ± 338 Bq/kg, respectively. The calculated values of Ra_eq are higher than the average world value (it must be less than 370 Bq/kg). Finally the external hazardous, internal hazardous and I_γr must be less than unity. This means that specific radiation protection program must be applied and implemented during monazite processing.

Propensity score-based analysis of outcomes of laparoscopic versus open liver resection for colorectal metastases

BACKGROUND

There is a need for high-level evidence regarding the added value of laparoscopic (LLR) compared with open (OLR) liver resection. The aim of this study was to compare the surgical and oncological outcomes of patients with colorectal liver metastases (CRLM) undergoing LLR and OLR using propensity score matching to minimize bias.

METHODS

This was a single-centre retrospective study using a prospective database of patients undergoing liver resection for CRLM between August 2004 and April 2015. Co-variates selected for matching included: number and size of lesions, tumour location, extent and number of resections, phase of surgical experience, location and lymph node status of primary tumour, perioperative chemotherapy, unilobar or bilobar disease, synchronous or metachronous disease. Prematching and postmatching analyses were compared. Surgical and oncological outcomes were analysed.

RESULTS

Some 176 patients undergoing LLR and 191 having OLR were enrolled. After matching, 133 patients from each group were compared. At prematching analysis, patients in the LLR group showed a longer overall survival (OS) and higher R0 rate than those in the OLR group (P = 0·047 and P = 0·030 respectively). Postmatching analyses failed to confirm these results, showing similar OS and R0 rate between the LLR and OLR group (median OS: 55·2 versus 65·3 months respectively, hazard ratio 0·70 (95 per cent c.i. 0·42 to 1·05; P = 0·082); R0 rate: 92·5 versus 86·5 per cent, P = 0·186). The 5-year OS rate was 62·5 (95 per cent c.i. 45·5 to 71·5) per cent) for OLR and 64·3 (48·2 to 69·5) per cent for LLR. Longer duration of surgery, lower blood loss and morbidity, and shorter postoperative stay were found for LLR on postmatching analysis.

CONCLUSION

Propensity score matching showed that LLR for CRLM may provide R0 resection rates and long-term OS comparable to those for OLR, with lower blood loss and morbidity, and shorter postoperative hospital stay.

Laparoscopic radical 'no-touch' left pancreatosplenectomy for pancreatic ductal adenocarcinoma: technique and results

Background

Laparoscopic left pancreatectomy has been well described for benign pancreatic lesions, but its role in pancreatic adenocarcinoma remains open to debate. We report our results adopting a laparoscopic technique that obeys established oncologic principles of open distal pancreatosplenectomy.

Methods

This is a post hoc analysis of a prospectively kept database of 135 consecutive patients undergoing laparoscopic left pancreatectomy, performed across two sites in the UK and the Netherlands (07/2007–07/2015 Southampton and 10/2013–07/2015 Amsterdam). Primary outcomes were resection margin and lymph node retrieval. Secondary endpoints were other perioperative outcomes, including post-operative pancreatic fistula. Definition of radical resection was distance tumour to resection margin >1 mm. All patients underwent ‘laparoscopic radical left pancreatosplenectomy’ (LRLP) which involves ‘hanging’ the pancreas including Gerota’s fascia, followed by clockwise dissection, including formal lymphadenectomy.

Results

LRLP for pancreatic adenocarcinoma was performed in 25 patients. Seven of the 25 patients (28 %) had extended resections, including the adrenal gland (n = 3), duodenojejunal flexure (n = 2) or transverse mesocolon (n = 3). Mean age was 68 years (54–81). Conversion rate was 0 %, mean operative time 240 min and mean blood loss 340 ml. Median intensive/high care and hospital stay were 1 and 5 days, respectively. Clavien–Dindo score 3+ complication rate was 12 % and ISGPF grade B/C pancreatic fistula rate 28 %; 90-day (or in-hospital) mortality was 0 %. The pancreatic resection margin was clear in all patients, and the posterior margin was involved (<1 mm) in 6 patients, meaning an overall R0 resection rate of 76 %. No resection margin was microscopically involved. Median nodal sample was 15 nodes (3–26). With an average follow-up of 17.2 months, 1-year survival was 88 %.

Conclusions

A standardised laparoscopic approach to pancreatic adenocarcinoma in the left pancreas can be adopted safely. Our study shows that these results can be reproduced across multiple sites using the same technique.

Outcome after pancreaticoduodenectomy for T3 adenocarcinoma: A multivariable analysis from the UK Vascular Resection for Pancreatic Cancer Study Group

BACKGROUND

Most resectable pancreatic cancers are classified as T3, including those involving the porto-mesenteric vein. Survival and perioperative morbidity for venous resection have been found to be comparable to standard resection. We investigate factors associated with short and long term outcomes in pancreaticoduodenectomy with (PDVR) and without (PD) venous resection exclusively for T3 adenocarcinoma of the head of the pancreas.

METHODS

This is a UK multicenter retrospective cohort study assessing outcomes in patients undergoing PD and PDVR. All consecutive patients with T3 only adenocarcinoma of the head of the pancreas undergoing surgery between December 1998 and June 2011 were included. Multivariable logistic and proportional hazards regression analyses were performed to determine the association between the surgical groups and in-hospital mortality (IHM) and overall survival (OS).

RESULTS

1070 patients were included of whom 840 (78.5%) had PD and 230 (21.5%) had PDVR. Factors independently associated with IHM were a high creatinine (aHR 1.14, p = 0.02), post-operative bleeding (aHR 2.86, p = 0.04) and a re-laparotomy (aHR 8.42, p = 0.0001). For OS, multivariable analyses identified R1 resection margin status (aHR 1.22, p = 0.01), N1 nodal status (aHR 1.92, p = 0.0001), perineural invasion (aHR 1.37, p = 0.002), tumour size >20mm (aHR 0.63, p = 0.0001) and a relaparotomy (aHR 1.84, p = 0.0001) to be independently associated with overall mortality.

CONCLUSION

This study on T3 adenocarcinoma of the head of the pancreas suggests that IHM is strongly associated with perioperative complications whilst OS is affected by histological parameters. Detailed pre-operative disease evaluation and advances in oncological treatment have the potential to improve OS.

Investigation of some factors affecting on release of radon-222 from phosphogypsum waste associated with phosphate ore processing

The aim of this study is oriented to investigate the influence of some physicochemical factors such as radium distribution, grain size, moisture content and chemical constituents on releases of radon-222 from the accumulated phosphogypsum (PG) waste. The emanation fraction, activity concentration in the pore and the surface exhalation rate of radon-222 in the bulk PG waste are 34.5 ± 0.3%, 238.6 ± 7.8 kBq m(-3) and 213 ± 6.9 mBq m(-2) s(-1), respectively. These values were varied and enhanced slightly in the fine grain sizes (F1 < 0.125 mm) by a factor of 1.05 folds compared to the bulk residue. It was also found that release of radon from residue PG waste was controlled positively by radium (Ra-226), calcium (CaSO4) and strontium (SrO). About 67% of radon release attributed to the grain size below 0.5 mm, while 33% due to the large grain size above 0.5 mm. The emanation fraction of Rn-222 is increased with moisture content and the maximum emanation is ∼43% of moisture of 3-8%. It reduced slowly with the continuous increase in moisture till 20%. Due to PG waste in situ can be enhancing the background to the surround workers and/or public. Therefore, the environmental negative impacts due to release of Rn-222 can be minimized by legislation to restrict its civil uses, or increasing its moisture to ∼10%, or by the particle size separation of the fine fraction containing the high levels of Ra-226 followed by a suitable chemical treatment or disposal; whereas the low release amount can be diluted and used in cement industry, roads or dam construction.

Outcome after surgical resection for duodenal adenocarcinoma in the UK

BACKGROUND

Factors influencing long-term outcome after surgical resection for duodenal adenocarcinoma are unclear.

METHODS

A prospectively created database was reviewed for patients undergoing surgery for duodenal adenocarcinoma in six UK hepatopancreaticobiliary centres from 2000 to 2013. Factors influencing overall survival and disease-free survival (DFS) were identified by regression analysis.

RESULTS

Resection with curative intent was performed in 150 (84·3 per cent) of 178 patients. The postoperative morbidity rate for these patients was 40·0 per cent and the in-hospital mortality rate was 3·3 per cent. Patients who underwent resection had a better median survival than those who had a palliative surgical procedure (84 versus 8 months; P < 0·001). The 1-, 3- and 5-year overall survival rates for patients who underwent resection were 83·9, 66·7 and 51·2 per cent respectively. Median DFS was 53 months, and 1- and 3-year DFS rates were 80·8 and 56·5 per cent respectively. Multivariable analysis revealed that node status (hazard ratio 1·73, 95 per cent c.i. 1·07 to 2·79; P = 0·006) and lymphovascular invasion (hazard ratio 3·49, 1·83 to 6·64; P = 0·003) were associated with overall survival.

CONCLUSION

Resection of duodenal adenocarcinoma in specialist centres is associated with good long-term survival. Lymphovascular invasion and nodal metastases are independent prognostic indicators.

Outcomes of repeat laparoscopic liver resection compared to the primary resection

BACKGROUND

Repeat laparoscopic liver resection (R-LLR) can be technically challenging. Data on this topic are scarce and many investigators would question its feasibility and outcomes. The aim of the present study was to evaluate the safety, feasibility, oncological efficiency and outcomes of R-LLR.

METHODS

We reviewed a prospectively collected database of 403 patients undergoing 422 laparoscopic liver resections (LLRs) from August 2003 to August 2013. Data of 19 patients undergoing R-LLR were analyzed and compared to the primary resection (P-LLR) in these patients. Demographic and clinical data were studied. A subgroup analysis was done for minor resections.

RESULTS

Twenty R-LLRs were performed in 19 patients (female 58 %; mean age: 57.5 years; age range: 23-79 years). Colorectal liver metastases (CRLM) were the commonest indication for R-LLR (60 %), followed by neuroendocrine tumor liver metastases (NETLM) (20 %) and hepatocellular carcinoma (HCC) (10 %). The majority (90 %) of resections were for malignant disease (18/20). There were three conversions (15 %), and two patients developed complications (10 %). The operative time (p = 0.005) and blood loss (p = 0.03) were both significantly greater in R-LLR compared to P-LLR, whereas length of stay (median 4 days; p = 0.30) and complications (p = 0.58) did not differ between the groups. R0 resection rates for P-LLR and R-LLR were 95 and 90 %, respectively (p = 0.73).

CONCLUSIONS

Repeat LLR is safe, feasible, and can be performed with minimal morbidity. It appears to be technically more challenging than P-LLR, but without any increase in complications or length of hospital stay.

Evaluation of radiation hazard potential of TENORM waste from oil and natural gas production

In this study, a potential radiation hazard from TENORM sludge wastes generated during exploration and extraction processes of oil and gas was evaluated. The activity concentration of natural radionuclides (238)U, (226)Ra and (232)Th were determined in TENORM sludge waste. It was found that sludge waste from oil and gas industry is one of the major sources of (226)Ra in the environment. Therefore, some preliminary chemical treatment of sludge waste using Triton X-100 was also investigated to reduce the radioactivity content as well as the risk of radiation hazard from TENORM wastes. The activity concentrations of (226)Ra and (228)Ra in petroleum sludge materials before and after chemical treatment were measured using gamma-ray spectrometry. The average values of the activity concentrations of (226)Ra and (228)Ra measured in the original samples were found as 8908 Bq kg(-1) and 933 Bq kg(-1), respectively. After chemical treatment of TENORM samples, the average values of the activity concentrations of (226)Ra and (228)Ra measured in the samples were found as 7835 Bq kg(-1) and 574 Bq kg(-1), respectively. Activity concentration index, internal index, absorbed gamma dose rate and the corresponding effective dose rate were estimated for untreated and treated samples.

Factors affecting the distribution of natural and anthropogenic radionuclides in the coastal Burullus Lake

In the present study, measurements of naturally occurring radioactive materials and (137)Cs activity in sediment were conducted for locations covering the entire Burullus Lake in order to gather information about radionuclides mobility and distribution. Low-background γ-spectrometry was employed to determine the activity concentrations of water and sediment samples. The activity concentrations of (226)Ra and (232)Th are close to uniform distribution in the lake environment. Among the different physical and chemical characteristics measured for water and sediment, only salinity and total organic matter content have the potential to affect the mobility of (137)Cs and (40)K. The results suggest that these two radionuclides are attached to different mobile particulates. Increasing salinity tends to strengthen the adsorption of (137)Cs and solubilization of (40)K in sediment. On the other hand, sediment with high organic matter content traps (137)Cs and (40)K associated particulates to bottom sediment.

Utilization of different crown ethers impregnated polymeric resin for treatment of low level liquid radioactive waste by column chromatography

The main goal of this study was to find a novel impregnated resin as an alternative for the conventional resin (KY-2 and AN-31) used for low and intermediate level liquid radioactive waste treatment. Novel impregnated ion exchangers namely, poly (acrylamide-acrylic acid-acrylonitril)-N,N'-methylenedi-acrylamide-4,4'(5')di-t-butylbenzo 18 crown 6 [P(AM-AA-AN)-DAM/DtBB18C6], poly (acrylamide-acrylic acid-acrylonitril)-N,N'-methylenediacrylamide-dibenzo 18 crown 6 [P(AM-AA-AN)-DAM/DB18C6], and poly (acrylamide-acrylic acid-acrylonitril)-N,N'-methylenediacrylamide-18 crown 6 [P(AM-AA-AN)-DAM/18C6] were prepared and their removal efficiency of some radionuclides was investigated. Preliminary batch experiments were performed in order to study the influence of the different derivatives of 18 crown 6 on the characteristic removal performance. Separation of (134)Cs, (60)Co, (65)Zn and ((152+154))Eu radionuclides from low level liquid radioactive waste was investigated by using column chromatography with P(AM-AA-AN)-DAM/DtBB18C6 and metal salt solutions traced with the corresponding radionuclides. Breakthrough data was obtained in a fixed bed column at room temperature (298K) using different bed heights and flow rates. The breakthrough capacities were found to be 94.7, 83.3, 58.7, 43.1 (mg/g) for (60)Co, (65)Zn, (134)Cs, and ((152+154))Eu, respectively. Pre-concentration and separation of all radionuclides under study have been carried out using different concentration of nitric and/or oxalic acids.

Short- and medium-term results of totally laparoscopic resection for colorectal liver metastases

BACKGROUND

Laparoscopic surgery for primary colorectal cancer is now commonplace but the uptake of laparoscopic surgery for colorectal liver metastasis (CRLM) has been slow, mainly owing to doubts regarding safety, feasibility and oncological efficiency.

METHODS

Prospectively collected data of all patients treated for CRLM between 2004 and 2009 were reviewed retrospectively. The database was analysed for operative details, hospital stay, postoperative results and medium-term survival.

RESULTS

Over 5 years, 135 patients underwent liver surgery for CRLM. For laparoscopic procedures, the median duration of operation was 220 min and median blood loss was 363 ml; a mean tumour-free resection margin of 17.0 mm was achieved (more than 1 cm in 76 per cent), and no port-site metastasis or surgical-site recurrence was observed. The procedure was converted to open surgery in six patients (two for bleeding). Overall survival for the laparoscopic group approached 90 per cent with median follow-up of 22 months.

CONCLUSION

In this series totally laparoscopic CRLM resection had good short- and medium-term results in terms of mortality, morbidity, resection margins, local recurrence or port-site metastasis, and survival. Compared with contemporaneous open experience, the laparoscopic approach was safe and effective in a highly selected consecutive series.

Characterization of phosphogypsum wastes associated with phosphoric acid and fertilizers production

The present work is directed to characterize the phosphogypsum (PG) wastes associated with phosphoric acid produced by the wet process in industrial facility for the production of fertilizers and chemicals in Egypt. The PG waste samples were characterized in terms of spectroscopic analysis (X-ray diffraction, X-ray fluorescence, IR spectra) and radiometric analysis (gamma- and alpha-measurements). The gamma-ray measurements showed that the average activity concentrations are 140+/-12.6, 459+/-36.7, 323+/-28.4, 8.3+/-0.76 and 64.3+/-4.1 Bq/kg for U-238, Ra-226, Pb-210, Th-232 and K-40, respectively. The alpha-particle measurements of uranium isotopes showed that the average activity concentrations of U-238, U-235 and U-234 were 153+/-9.8, 7+/-0.38, 152+/-10.4 Bq/kg, respectively. The average radiochemical recovery (%) of the destructive alpha-particle measurements is approximately 70% with a resolution (FWHM) of approximately 30 keV. Activity ratios of U-238/Ra-226 and U-238/Pb-210 were less than unity (i.e., <1) and equal to 0.31+/-0.02 and 0.47+/-0.16, respectively. The isotopic ratios of U-238/U-235 and U-238/U-234 (in PG and PR samples) were close to the normal values of approximately 21.7 and approximately 1, respectively and are not affected by the wet processing of phosphate rock (PR). The obtained results of PG waste samples were compared with phosphate rock (PR) samples. The radiation hazard indices are namely, radium activity index (Ra-Eq>370 Bq/kg), total absorbed gamma dose rate (D(gamma r)>5 nGy/h) and radon emanation fraction (Rn-EF>20%). Uncertainty of the sample counting was 95% confidence level of sigma. The results indicated the necessity to find suitable routes to decrease and/or redistribute the radionuclide of environmental interest (i.e., Ra-226) in PG wastes, consequently to reduce its radiation impacts in the surrounding environment.

Sequential chemical treatment of radium species in TENORM waste sludge produced from oil and natural gas production

This paper is dedicated to the treatment of sludge occurring in frame of the Egyptian produced from oil and gas production. The activity levels of three radium isotopes: Ra-226 (of U-series), Ra-228 and Ra-224 (of Th-series) in the solid TENORM waste (sludge) were first evaluated and followed by a sequential treatment for all radium species (fractions) presented in TENORM. The sequential treatment was carried out based on two approaches 'A' and 'B' using different chemical solutions. The results obtained indicate that the activity levels of all radium isotopes (Ra-226, Ra-228 and Ra-224) of the environmental interest in the TENORM waste sludge were elevated with regard to exemption levels established by IAEA [International Atomic Energy Agency (IAEA), International basic safety standards for the protection against ionizing radiation and for the safety of radiation sources. GOV/2715/Vienna, 1994]. Each approach of the sequential treatment was performed through four steps using different chemical solutions to reduce the activity concentration of radium in a large extent. Most of the leached radium was found as an oxidizable Ra species. The actual removal % leached using approach B was relatively efficient compared to A. It is observed that the actual removal percentages (%) of Ra-226, Ra-228 and Ra-224 using approach A are 78+/-2.8, 64.8+/-4.1 and 76.4+/-5.2%, respectively. Whereas in approach A, the overall removal % of Ra-226, Ra-228 and Ra-228 was increased to approximately 91+/-3.5, 87+/-4.1 and 90+/-6.2%, respectively.

Hepatic splenosis mimicking HCC in a patient with hepatitis C liver cirrhosis and mildly raised alpha feto protein; the important role of explorative laparoscopy

Background

Splenosis is a heterotropic implantation of splenic fragments onto exposed vascularised peritoneal and intrathoracic surfaces, following splenic injury or elective splenectomy.

Case presentation

A 60 year old cirrhotic patient was referred to us with a hepatic mass, suspected to be HCC in a cirrhotic liver. A computerized tomography scan (CT) demonstrated a cirrhotic liver with a 2 × 2.7 cm focal hypervascular nodule, lying peripherally at the junction of segment 7 and 8. Diagnostic laparoscopy demonstrated a 3 cm exofitic dark brown splenunculus attached to the diaphragm and indenting the surface of segment 7 of the liver. The lesion was easily resected laparoscopically and shaved from the live surface with no need for a liver resection. The histopathological assessment confirmed the diagnosis of splenunculus, with no evidence of neoplasia.

Conclusion

Hepatic splenosis is not a rare event and should be suspected in patients with a history of splenic trauma or splenectomy. Correct diagnosis is essential and will determine subsequent management plans. In doubtful cases laparoscopic investigation can offere essential information and should be part of the standard protocol for investigating suspected splenosis.

Laparoscopic left lateral liver sectionectomy: a safe, efficient, reproducible technique

BACKGROUND

Laparoscopic left lateral sectionectomy (LLLS) is procedure with potential for future transformation into a primarily laparoscopic procedure where surgeons can safely develop laparoscopic experience and gain proficiency.

METHODS

Between August 2004 and December 2007, 80 patients underwent laparoscopic liver resections in our unit, 30 of these were left lateral sectionectomies. The indications for surgery were both oncological and non-oncological.

RESULTS

30 LLLS were performed. Median operative time and median postoperative hospital stay group were 180 (40-340) min and 4 (1-6) days, respectively, and were noted to fall significantly between the first (15 patients) and second parts of this series. The median free resection margin was 11 (1.5-30) mm and median perioperative blood loss was 80 (25-800) ml. Two minor complications were observed with no mortality and no conversions to open.

CONCLUSION

LLLS is a feasible, safe and efficient procedure, associated with a quick, smooth learning curve. We report our technique illustrating methods and particulars which would be of great help to surgeons developing new laparoscopic liver services.

Laparoscopic versus open left lateral hepatic sectionectomy: A comparative study

BACKGROUND

Laparoscopic liver surgery has been difficult to popularize. High volume liver centres have identified left lateral sectionectomy (LLS) as a procedure with potential for transformation into a primarily laparoscopic procedure where surgeons can safely gain proficiency.

METHODS

Forty-four patients underwent either laparoscopic (LLLS) or open (OLLS) left lateral sectionectomy (of segments II/III) for focal lesions at Southampton General Hospital.

RESULTS

OLLS and LLLS groups were matched for age, sex and tumour types resected. Median operative time in the LLLS group was 180 (40-340) min and 155 (110-330) min in the OLLS group (p=0.885) with median intra-operative blood loss in the LLLS group 80 (25-800) ml versus a larger 470 (100-3000) ml; p=0.002 for patients receiving OLLS. Post-operative stay was also shorter in the LLLS group (3.5 (1-6) days) compared to the OLLS group (7 (3-12) days; p<0.001). Resection margin was not different in the two groups (11 (1.5-30) mm (LLLS) versus 12 (4-40) mm (OLLS); p=1) and neither was the complication rate (13% for LLLS versus 25% for OLLS; p=0.541). There were no conversions to open in the LLLS group and no deaths in either group at 90 days. Between the first and second 12 LLLS the median operative time fell from 240 (70-340) min to 120 (40-120) min; p=0.005 as well as median post-operative hospital stay from 4.5 (2-6) days to 2 (1-4) days, p=0.001.

CONCLUSION

LLLS is a viable alternative to OLLS with potential improvements in intra-operative blood loss and shorter hospital stay without adversely affecting successful resection or complication rates. Larger prospective studies are required to explore this new avenue in laparoscopic liver surgery.

Management of a ruptured pseudoaneurysm of common hepatic artery following pancreaticoduodenectomy

Postoperative pseudoaneurysm formation is one of the most feared complications of pancreatic leak following pancreaticoduodenectomy (PD). Surgical repair may be compromised due to a persistent enzymatic insult on the repaired vessel; therefore, preventive measures should be adopted. We report a case of ruptured hepatic artery pseudoaneurysm occurring 12 days following PD in a patient with a postoperative pancreatic fistula. Emergency surgery revealed that the pseudoaneurysm was situated at the point of surgical transfixation of the gastroduodenal artery. The pseudoaneurysm was successfully managed by under-running of the bleeding point combined with the direct application of hemostatic products to the bleeding surface (TachoSil and Tisseel to act as a barrier from the pancreatic secretions.