Irreversible electroporation to bring initially unresectable locally advanced pancreatic adenocarcinoma to surgery: the IRECAP phase II study

OBJECTIVES

The aim of the IRECAP study was to evaluate the rate of locally advanced pancreas cancer patients (LAPC) who could undergo R0 or R1 surgery after irreversible electroporation (IRE).

MATERIALS AND METHODS

IRECAP study is a phase II, single-center, open-label, prospective, non-randomized trial registered at clinicaltrials.gov (NCT03105921). Patients with LAPC were first treated by 3-month neo-adjuvant chemotherapy in order to avoid inclusion of either patients with LAPC having become resectable after chemotherapy or patients with rapid disease progression. In cases of stable disease, IRE was performed percutaneously under CT guidance. Surgery was planned between 28 and 90 days after IRE. Tumor specimens were studied to evaluate the resection margins (R0/R1/R2).

RESULTS

Six men and 11 women were included (median age 61 years, range 37-77 years). No IRE-related death was observed. Ten patients (58%, 10/17) experienced 25 serious adverse events related to IRE. Four patients progressed between IRE and surgery and were excluded from surgery. Thirteen patients were finally operated, six withheld for pancreas resection, three for diffuse peritoneal carcinosis, two for massive vascular entrapment, and one for hepato-cellular carcinoma not diagnosed before surgery. Rate of R1-R0 was 35% (n = 6/17). Median overall survival was 31 months (95% CI; 4-undefined) for the six patients with R0/R1 resection and 21 months (95% CI; 4-25) for the 11 patients without resection or R2 resection (logrank p = 0.044).

CONCLUSION

After neoadjuvant chemotherapy, IRE could provide R0 or R1 resection in 35% of LAPC, which seems to be associated with higher OS.

CLINICAL RELEVANCE STATEMENT

After induction chemotherapy, stable locally advanced pancreatic cancers can be treated by irreversible electroporation, which could lead to a secondary 35% rate of R0 or R1 surgical resection which may be associated with a significantly higher overall survival.

KEY POINTS

• In cases of unresectable LAPC (locally advanced pancreatic cancer), percutaneous irreversible electroporation (pIRE) is feasible (100% success rate of the procedure), but is associated with a 58% rate of grade 3-4 adverse events. • In patients with unresectable LAPC, pIRE could lead 35% of patients to R0-R1 surgical resection. • From IRE, median overall survival was 31 months (95% CI; 4-undefined) for the patients with R0/R1 resection and 21 months (95% CI; 4-25) for the patients without resection or R2 resection (logrank p = 0.044).

Development and validation of a performance assessment checklist for insertion of an intra-uterine device (IUD)

OBJECTIVES

The World Health Organization (WHO) supports increasing the availability and acceptability of long-acting reversible contraception including intra-uterine device (IUD), but its insertion includes certain risks (uterine perforation). The objective was to develop and validate an IUD insertion performance assessment checklist.

MATERIAL AND METHODS

This prospective study took place in hospitals and simulation center of the Poitou-Charentes region, France. The checklist content reached consensus among 10 experts solicited by a Delphi method. A modified gynecologic mannequin Zoe (Gaumard®) was used for simulations. Psychometric testing included 30 multi-professional participants for internal consistency and reliability between two independent observers, and 27 residents for assessment of score evolution over time and reliability. Cronbach alpha (CA) and intraclass coefficient (ICC) were used. Progression of performance was carried out using ANOVA for repeated measures. The data collected were used to plot receiver operating characteristic (ROC) curves for the score values and the area under the curve (AUC) was determined.

RESULTS

The checklist included 27 items (2 sections, total score = 27). Psychometric testing showed CA = 0.79, ICC = 0.99, and good clinical relevance. The checklist is discriminative, showing a significant increase in performance scores when the simulations were repeated (F = 77.6, p < 0.0001). ROC curve [AUC: 0.792 (95% CI: 0.71-0.89); p < 0.0001] revealed the best score cutoff predictive of 100% sensitivity, i.e., true positive rate or success rate. Performance score was highly correlated to success rate. The cut-off score guaranteeing successful IUD insertion was 22/27.

CONCLUSIONS

This coherent and reproducible checklist for IUD insertion provide an objective assessment of the procedure during SBT, with the aim of obtaining a score ≥ 22/27.

[Flap harvest training on a new ultrarealistic simulation model: In-training operator feedback about a pulsating reperfused and reventilated cadaver Simlife®]

INTRODUCTION

The anatomical subject is still a key element to learn complex procedures in plastic surgery. We present here the evaluation of an in-training operator on a SIMLIFE® model, hyper realistic model consisting in human bodies donated to science equipped with pulsating recirculation and reventilation device.

MATERIAL AND METHODS

From February 2019 to October 2019, 8 forearm flaps with radial proximal pedicle were harvested by the learner on a SIMLIFE® model. Conditions were as close as possible to the operating room : asepsy, sterile draping, assistant and instrumentation including electrocoagulation.

RESULTS

The procedure was decomposed in 13 distinct steps. Mean total surgery time was 90,5±11,62minutes. There was only one case of arterial pedicle lesion resulting in major blood leak. Bleeding was measured by fake blood loss from the SIMLIFE® console. Mean intraoperatoy bleeding was 171±108 milliliters. We review pros and cons of this new technology particulary suited for complex plastic and reconstructive surgery training.

CONCLUSION

Using SIMLIFE® technology we have a new mean to train for complex procedures in plastic and reconstructive surgery. This new technology could be applied to numerous other surgical procedures. Broader applications are still limited by cost and cadaver use legislation.

Should we recommend occipital plate fixation using bicortical screws or inverted occipital hooks to optimize occipito-cervical junction fusion? A biomechanical study combining an experimental and analytical approach

BACKGROUND

Occipito-cervical fusion can be necessary in case of cranio-cervical junction instability. Proximal stabilisation is usually ensured by bi-cortical occipital screws implanted through one median or two lateral occipital plate(s). Bone thickness variability as well as the proximity of vasculo-nervous elements can induce substantial morbidity. The choice of site and implant type remains difficult for surgeons and is often empirically based. Given this challenge, implants with smaller pitch to increase bone interfacing are being developed, as is a surgical technique consisting in inverted occipital hook clamps, a potential alternative to plate/screws association. We present here a biomechanical comparison of the different occipito-cervical fusion devices.

METHODS

We have developed a 3D mark tracking technique to measure experimental mechanical data on implants and occipital bone. Biomechanical tests were performed to study the mechanical stiffness of the occipito-cervical instrumentation on human skulls. Four occipital implant systems were analysed: lateral plates+large pitch screws, lateral plates+hooks, lateral plates+small pitch screws and median plate+small pitch screws. Mechanical responses were analysed using 3D displacement field measurements from optical methods and compared with an analytical model.

FINDINGS

Paradoxical mechanical responses were observed among the four types of fixations. Lateral plates+small pitch screws appear to show the best accordance of displacement field between bone/implant/system interface providing higher stiffness and an average maximum moment around 50 N.m before fracture.

INTERPRETATION

Stability of occipito-cervical fixation depends not only on the site of screws implantation and occipital bone thickness but is also directly influenced by the type of occipital implant.

SimLife model: introducing a new teaching device in endocrine surgery simulation

To evaluate the validity and reliability of an innovative training model for endocrine surgical procedures. A simulator training model for endocrine procedures (SimLife) was developed at an academic center. The model consisted of a realistic operating environment with a coherent simulated patient dynamized by pulsatile vascularization with simulated blood warmed to 37 °C, and ventilation. Training sessions were designed for adrenal and thyroid surgery, as well as neck dissection. The primary outcome of interest was to evaluate learners’ performance and satisfaction. Learners’ performance was evaluated based on a scoring scale that followed the Downing method for the assessment of competency. While learners’ satisfaction was evaluated using a Likert scale of 1 to 10 on four items (ease of learning, anatomic correspondence of landmarks, realism, and overall satisfaction). Participants were engaged in 32 training sessions. These included 24 adrenalectomies (conventional and laparoscopic both transabdominal and posterior), and 4 thyroid lobectomies with concomitant functional lateral compartment neck dissection. competency scores were procedure-specific addressing specific core components of a given procedure. Learners’ performance scored above average in all procedures evaluated. Satisfaction scores for the specified four items ranged between 8.43 (SD 0.87) and 8.89 (SD 0.96). No major events were reported for the adrenalectomies, while only one jugular vein injury occurred during neck dissection. SimLife is a hyper-realistic training model that allows for satisfactory acquisition of skills and the evaluation of performance progression. It has the potential to become a cornerstone in specialized surgical training.

[Male to female sex reassignment surgery with a new surgical simulation device using a human perfused cadaver SIMLIFE®: New paradigm in transsexual surgery education ?]

INTRODUCTION

In 2015, we reported our experience with the learning curve in genital reassignment surgery and highlighted a four-step learning concept.

CLINICAL CASE

In this article, we present our first vaginoplasty performed on a humanoid model SIMLIFE®, a human body associated with a pulsating circulation device and a ventilation device.

RESULTS

The surgical technique included 14 steps. The total surgical time was 182minutes. There was no intraoperative complication, and there was no damage to the urethra or rectum. The intraoperative bleeding measured by the loss of operative fluid was 280mL. We discuss the advantages of this technology perfectly adapted to transsexual surgery.

CONCLUSION

We demonstrated the feasibility of vaginoplasty performed on a humanoid model SIMLIFE® and highlighted improvement of the surgical skills with this model. This technology could find many other surgical applications. However, it faces cost constraints and legislation on corpses.

Predictive factors of endocrine and exocrine insufficiency after resection of a benign tumour of the pancreas

BACKGROUND

The aim of the present study is to evaluate the risk factors of endocrine and exocrine insufficiency occurring few years after pancreatic resections in a consecutive series of patients who underwent pancreatoduodenectomy (PD), left pancreatectomy (LP) or enucleation for benign neoplasms at a referral centre.

METHODS

Pancreatic exocrine insufficiency (PEI) was defined by the onset of steatorrhea associated with weight loss, and endocrine insufficiency was determinate by fasting plasma glucose. Association between pancreatic insufficiency and clinical, pathological, and perioperative features was studied using univariate and multivariate Cox regression analysis.

RESULTS

A prospective cohort of 92 patients underwent PD (48%), LP (44%) or enucleation (8%) for benign tumours, from 2005 to 2016 in the University Hospital in Poitiers (France). The median follow-up was 68.6±42.4months. During the following, 54 patients developed exocrine insufficiency whereas 32 patients presented endocrine insufficiency. In the Cox model, a BMI>28kg/m², being a man and presenting a metabolic syndrome were significantly associated with a higher risk to develop postoperative diabetes. The risks factors for the occurrence of PEI were preoperative chronic pancreatitis, a BMI<18.5kg/m², tumours located in the pancreatic head, biological markers of chronic obstruction and fibrotic pancreas. Undergoing LP or enucleation were protective factors of PEI. Histological categories such as neuroendocrine tumours and cystadenomas were also associated with a decreased incidence of PEI.

CONCLUSION

Men with metabolic syndrome and obesity should be closely followed-up for diabetes, and patients with obstructive tumours, pancreatic fibrosis or chronic pancreatitis require a vigilant follow up on their pancreatic exocrine function.

Colonoscopy uptake for high-risk individuals with a family history of colorectal neoplasia: A multicenter, randomized trial of tailored counseling versus standard information

BACKGROUND

Colonoscopic screening is recommended for first-degree relatives of patients diagnosed with colorectal cancer (CRC) or colorectal adenomatous polyps (CAP) before the age of 60 years. This has the potential to reduce CRC-related morbidity and mortality, but uptake is currently inadequate.

METHODS

The aim of the study was to compare the effectiveness of standard information versus a nurse-led tailored intervention designed to promote uptake of colonoscopy screening by siblings of CRC or CAP patients. A randomized controlled trial was conducted. Digestive surgeons and gastroenterologists recruited index patients who developed CRC or CAP before the age of 60 years. All index patients received standard screening information for their siblings, in keeping with current guidelines. Centrally computerized randomization of index patients resulted in allocating all their siblings to the same group, intervention or control. The tailored intervention targeted the index patient first, to help them convey information to their siblings. The nurse then provided the siblings with tailored information based on their answers to a self-questionnaire which explored health behaviors, derived from psychosocial models of prevention. Then the siblings were given a personalized information leaflet to hand to their regular physician. The primary endpoint was the rate of documented colonoscopy performed in siblings within 1 year after diagnosis of the index patient. The intent-to-treat analysis included siblings who refused to participate in the study. Statistical analysis was adjusted for intrafamilial correlation.

RESULTS

A total of 304 siblings of 125 index patients were included: 160 in the intervention group and 144 in the control group. The rate of colonoscopy uptake among siblings was 56.3% in the intervention group and 35.4% in the control group (P = 0.0027). The respective rates after exclusion of refusals were 69.2% and 37.0% (P < 0.0001). More lesions were detected in the intervention group (1 invasive cancer and 11 advanced adenomas vs 5 advanced adenomas; P = 0.022).

CONCLUSIONS

This study demonstrates the effectiveness of a nurse-led tailored intervention designed to promote colonoscopy screening uptake by siblings of patients diagnosed with CRC or CAP before age 60 years. Such tailored interventions that also involve physicians should help to reduce CRC-related mortality.

Development of a µ-TPC detector as a standard instrument for low-energy neutron field characterisation

In order to measure the energy and fluence of neutron fields, in the energy range of 8 to 1 MeV, a new primary standard is being developed at the Institute for Radioprotection and Nuclear Safety (IRSN). This project, Micro Time Projection Chamber (µ-TPC), carried out in collaboration with the Laboratoire de Physqique Subatomique et de Cosmologie (LPSC), is based on the nucleus recoil detector principle. The measurement strategy requires track reconstruction of recoiling nuclei down to a few kiloelectronvolts, which can be achieved using a micro-pattern gaseous detector. A gas mixture, mainly isobutane, is used as an n-p converter to detect neutrons within the detection volume. Then electrons, coming from the ionisation of the gas by the proton recoil, are collected by the pixelised anode (2D projection). A self-triggered electronics system is able to perform the anode readout at a 50-MHz frequency in order to give the third dimension of the track. Then, the scattering angle is deduced from this track using algorithms. The charge collection leads to the proton energy, taking into account the ionisation quenching factor. This article emphasises the neutron energy measurements of a monoenergetic neutron field produced at 127 keV. The fluence measurement is not shown in this article. The measurements are compared with Monte Carlo simulations using realistic neutron fields and simulations of the detector response. The discrepancy between experiments and simulations is 5 keV mainly due to the calibration uncertainties of 10 %.

Reliability and validity of a new measurement of lumbar foraminal volume using a computed tomography

PURPOSE

Measuring foraminal stenosis is generally determined by an area calculation. It is difficult to know exactly where it is most appropriate to measure. No precise data are available on a method for calculating the foraminal volume using a CT. To develop a new method for measuring lumbar foraminal volume, we analyzed repeatability and reliability for measuring methods for foraminal volume using CT.

METHODS

The measurements were performed using a CT scan from ten healthy patients, with a mean age of 26.3 years. L3-L4, L4-L5 and L5-S1 foramen were studied, to obtain 60 foraminal measurements. Inter- and intra-observer reproducibility was calculated. Each series was analyzed using the VitreaCore® reconstruction software for volume calculation.

RESULTS

Average volume measurements of 60 foramina and 20 L4-L5 foramina were, respectively, 1.17 and 1.25 mm(3) for observer 1 and 1.21 and 1.29 for observer 2. The intra-observer correlation coefficients for observer 1 when measuring all foramina and L4-L5 foramina were 0.98 and 0.99, respectively. For observer 2, coefficients were 0.90 and 0.92, respectively. The inter-observer correlation coefficients for observer 1 when measuring all foramina and L4-L5 foramina were 0.78 and 0.83, respectively. For observer 2, coefficients were 0.77 and 0.8, respectively. The average differences in intra- and inter-observer measurements regardless of the evaluator group were less than 0.2 mm(3).

CONCLUSIONS

This is the first study measuring lumbar foraminal volume using CT. The excellent reproducibility of this simple measure can supplement a range of foramen measurement tools.

Influence of nephron mass and a phosphorylated 38 mitogen-activated protein kinase inhibitor on the development of early and long-term injury after renal warm ischaemia

BACKGROUND

Renal ischaemia is accompanied by acute and chronic complications. Tumour necrosis factor (TNF) alpha production via p38 mitogen-activated protein kinase (MAPK) is one of the pivotal mechanisms linking ischaemia to inflammation and could be a therapeutic target. FR167653 (FR), an inhibitor of p38 MAPK and TNF-alpha production, may ameliorate renal damage through its effects on TNF-alpha.

METHODS

Warm ischaemia (WI) was induced in male pigs by bilateral clamping of the renal pedicle for 60 min or unilateral renal clamping after contralateral nephrectomy. FR was administered before and during WI, and continuously for 3 h during reperfusion in pigs exposed to the same WI conditions. Experimental groups were compared with sham-operated pigs and those subjected to unilateral nephrectomy without renal ischaemia. Renal function, fibrosis and inflammation were evaluated, and expression of monocyte chemoattractant protein 1, transforming growth factor beta and TNF-alpha was determined after 12 weeks.

RESULTS

FR significantly reduced renal failure in groups subjected to unilateral nephrectomy and bilateral renal ischaemia. Proteinuria was significantly reduced, and inflammation and expression of proinjury proteins were diminished, accompanied by a reduction in renal fibrosis.

CONCLUSION

Control of TNF-alpha production and activity prevents renal damage after prolonged WI.

Abnormalities of the gallbladder, clinical effects

The aim of this review of the literature was to present and discuss the anatomical and embryological basis of congenital abnormalities of the gallbladder, based on a case of volvulus. In the rare cases of ectopic gallbladder, diagnosis of a biliary disease could be difficult. In such cases surgery can also be dangerous, especially when it is associated with abnormalities of the intra-hepatic biliary and vascular tree. This study, based on the embryology of the extra hepatic bile duct, focused on the most frequent gallbladder abnormalities to keep them in mind.

Protective role of selectin ligand inhibition in a large animal model of kidney ischemia-reperfusion injury

Experiments in rodents have demonstrated an important role for selectins in kidney ischemia-reperfusion injury (IRI). However, the relevance of this in larger mammals, as well as the impact on long-term structure and function is unknown. We tested the hypothesis that small molecule selectin ligand inhibition attenuates IRI, cellular inflammation, and long-term effects on renal interstitial fibrosis. We used a porcine model of kidney IRI and used Texas Biotechnology Corporation (TBC)-1269, a selectin ligand inhibitor. Renal function, tissue inflammation, and tubulointerstitial fibrosis development were evaluated up to 16 weeks. Both warm and cold ischemia models were studied for relevance to native and transplant kidney injury. Pigs treated with TBC-1269 during 45 min of warm ischemia (WI) showed significantly increased glomerular filtration rate compared to control animals. In pigs with severe IRI (WI for 60 min), TBC-1269 treatment during IRI significantly increased renal recovery. Cellular inflammation was strongly reduced, particularly influx of CD4 cells. Quantitative measurement of fibrosis by picrosirius red staining showed strong reduction in TBC-1269-treated groups. TBC-1269 also reduced cold IRI, inflammation, and fibrosis in kidneys preserved for 24 h at 4 degrees C and autotransplanted. The selectin ligand inhibitor TBC-1269 provides a novel and effective approach to attenuate IRI in both warm and cold ischemia in large mammals, in both short and long terms. Selectin ligand inhibition is an attractive strategy for evaluation in human kidney IRI.

Anatomical pitfalls in the technique for total extra peritoneal laparoscopic repair for inguinal hernias

PURPOSE

The totally extraperitoneal laparoscopic approach for the treatment of inguinal hernia is a well-recognized technique with proven efficacy, low failure rate, and reduced post-operative pain. This laparoscopic technique is reputed to be a more difficult procedure to learn and practice than a laparoscopic trans-abdomino-pre-peritoneal procedure: we hope this is because many surgeons don't well know extra-peritoneal anatomy of groin. So we proposed a "step by step" anatomical analysis, with pitfalls to avoid, of a totally extraperitoneal laparoscopic approach for treatment of inguinal hernia.

METHODS

Our experience with totally extraperitoneal laparoscopic inguinal hernia repair with regard to the morphology of the inguinal-femoral region concerns 23 cadaver dissection and more than 400 surgical procedures, now permits clarification of a surgical technique that has hitherto not been well known.

CONCLUSION

Photographic representations of surgical views are displayed, and detailed descriptions applicable to anatomical structures are presented.

[Torsion of the spleen in children]

The wandering spleen is caused by congenital absence of fixating ligaments or abnormally long ligaments. It is an uncommon clinical entity, which rarely affects children. The clinical presentation of wandering spleen is variable, but the most dangerous complication is splenic torsion. A 7 year-old boy presented with abdominal pain and vomiting. The abdominal ultrasound scan discovered spleen ischemia. Volvulus of the spleen was evoked. Laparotomy was carried out and the patient underwent splenectomy. In this case the anatomical means of spleen fixity were absent. Because wandering spleen is uncommon in the paediatric population, a heightened awareness of the condition is required for accurate diagnosis and appropriate management. The treatment of choice is splenopexy, while if splenic necrosis is present, splenectomy is required.

[How is an abdominal hernia formed?]

Abdomen can be compared in broad outline with an irregular cylinder, limited at the top by the diaphragm and below by the pond. The walls of this cylinder are musculo-aponevrotic and present "zones of weakness" seats of the hernias of the abdominal wall. We propose a topographic anatomical approach of abdominal hernias.

[Operable lung cancer and synchronous adrenal masses: role of laparoscopic adrenalectomy combined with pulmonary resection]

STUDY AIM

Assessment of laparoscopic adrenalectomy in the management of operable non-small cell lung cancer (NSCLC) associated with solitary and synchronous adrenal mass.

PATIENTS AND METHODS

In a retrospective study, we reviewed 3 patients with operable NSCLC proved by pulmonary biopsy and an isolated synchronous adrenal mass shown by abdominal CT scan. We first performed a laparoscopic adrenalectomy followed by pulmonary resection.

RESULTS

All patients had a laparoscopic adrenalectomy without any conversion or treatment-related death. Hospitalization stay ranged from 5 to 6 days. A left pneumonectomy has been performed immediately after this first hospitalization in 2 cases and after a first cycle of chemotherapy in the third case. Pathologic examination showed a NSCLC adrenal metastasis in 2 cases and an adrenocortical adenoma in the last case. During the follow-up 2 patients died of other distant metastasis and a mediastinal lymph node recurrence has been diagnosed in the third patient, actually treated by a second line chemotherapy.

CONCLUSION

Despite those bad results that concern patients T3 M+ in 2 cases, laparoscopic adrenalectomy seems to be very interesting in selected cases. Considering that pulmonary resection can be done after, it represents a mean of diagnosis at least better than fine needle aspiration biopsy. Laparoscopic adrenalectomy might also be considered in the resection of a synchronous and isolated metastasis as a way to improve survival.

The pectineal ligament: anatomical study and surgical applications

The aim of this study was to reinforce the importance of the pectineal ligament in laparoscopic surgery for groin hernia and female urinary incontinence, particularly its anatomical importance in the myopectineal region. A morphologic study was conducted on 44 pectineal ligaments from 23 embalmed and one fresh human cadavers, together with a radiological study on four volunteer patients. Anatomical and histological findings confirm the fact that the ligament of Cooper represents a thickening of the pectineal fascia rather than a thickening from the periosteum. The pectineal ligament provides a landmark in each approach, open or laparoscopic, anterior or posterior surgery.

[Effect of preservation of the kidney on the long-term function following autotransplantation]

The consequences of ischaemia-reperfusion injury from kidney recipients on delayed graft function and graft survival still remain a matter of debate. Using an autotransplanted pig kidney model, the influence of trimetazidine added to two standard preservation solutions (Euro-Collins and University of Wisconsin) was studied. The renal parameters were analysed over a period of 12 weeks after transplantation. The degree of interstitial fibrosis, and the number of CD4, CD8 and macrophage positive cells were analysed at 2, 4-5 and 11-12 weeks after the transplantation. Glomerular filtration and sodium reabsorption were significantly more improved after cold-flush and preservation with trimetazidine-supplemented solutions than with trimetazidine-free solutions. The cytoprotective action of trimetazidine also reduced interstitial fibrosis and the number of infiltrating CD4 and CD8-positive cells. These results indicate that the condition of cold preservation may influence long-term kidney graft functions and that trimetazidine reduces to a certain extent the degree of interstitial fibrosis.

A prospective radiological anatomical study of the variations of the position of the colon in the left pararenal space

Percutaneous puncture of the kidney allows direct access to the pyelocalicial cavities. The posterior approach of this retroperitoneal organ can be complicated of transcolic punctures due to the postrenal position of the colon. A prospective radiological anatomical study of the relationship between the left kidney and the descending colon was undertaken. One hundred computed tomograms of adult subjects were obtained from which the anatomy of the left perirenal area was determined: the descending colon is more frequently behind the kidney in the young females. Two main factors determinants of this situation are: 1) colon ontogenesis in relation to the attachment of the primitive mesocolon, permitting a 'fixed' left colon, or 'moving' left colon at the end of a long mesocolon, allowing it to pass behind the kidney; 2) a mechanical factor whereby the accumulation of perirenal fat with increasing age may be a limiting factor in lateral displacement of the colon.

Pancreatic metastasis of renal cell carcinoma: presentation, treatment and survival

PURPOSE

The pancreas is an uncommon site of metastasis from renal cell carcinoma, comprising 2% of pancreatic tumors removed in sizable series of operations. To our knowledge the role of operative resection in the setting of metastatic malignancy to the periampullary region has not yet been defined. We reviewed the records of 6 women and 2 men who underwent pancreatic resection due to malignancy and analyzed various prognostic factors.

MATERIALS AND METHODS

Between 1985 and 1995, 269 patients underwent pancreatic resection for malignancy at our hospitals, including 150 (56%) for pancreatic duct cancer, 65 (24%) for carcinoma of the ampulla, 27 (10%) for distal bile duct cancer, 19 (7%) for duodenal carcinoma and 8 (3%) for renal cell carcinoma metastasis. We reviewed the records of these latter 8 cases, and analyzed demographics, primary tumor type, disease-free interval, resection type, concomitant other organ resection, histological examination of the specimen, morbidity, adjuvant therapy and survival.

RESULTS

Pancreatic metastasis of renal cell carcinoma was managed by duodenopancreatectomy in 5 patients and total pancreatectomy in 3. There were no perioperative deaths. Mean tumor size in cases of a solitary pancreatic metastasis was 4 cm. (range 1.5 to 8). In the 3 patients treated with total pancreatectomy there were 2, 5 and 3 pancreatic metastases, respectively. Pathological examination revealed negative lymph nodes in all cases. Mean survival was 48 months. At study end 6 patients were alive at 24, 26, 30, 46, 84 and 88 months, while 2 died at 13 and 70 months, respectively.

CONCLUSIONS

We advocate aggressive surgical resection when possible. Surgical removal of metastatic lesions prolongs survival but radical lymph node dissection is not mandatory. We also recommend careful long-term followup of patients with a history of renal cell carcinoma.

Influence of retrieval conditions on renal medulla injury: evaluation by proton NMR spectroscopy in an isolated perfused pig kidney model

BACKGROUND

Delayed graft function (DGF) has remained an important complication after renal transplantation. The exact causes of DGF remain to be clarified, particularly the impact of retrieval conditions and preservation factors. In the present investigation, (1)HNMR spectroscopy of urine was assessed in order to detect the influence of retrieval condition on renal medulla damage.

METHODS

The isolated perfused pig kidney (IPK) was used to assess initial renal function from multiorgan donors (MOD) or single organ donors (SOD) after in situ cold flush and 24-h cold storage (CS) preservation with two standard preservation solutions: Euro-Collins (EC) and University of Wisconsin (UW) solutions. Kidneys flushed with cold heparinized saline and immediately perfused were used as the control group. Kidneys were perfused for 90 min at 37.5 degrees C for functional evaluation. During reperfusion, renal perfusion flow rate (PF) was measured. Glomerular filtration rate (GFR), tubular reabsorption of Na(+), and lactate dehydrogenase (LDH) and N-acetyl-beta-d-glucosaminidase (NAG) excretions were determined. Ischemia-reperfusion impairment was also determined by histological techniques and (1)HNMR spectroscopy.

RESULTS

PF, GFR, and tubular reabsorption of Na(+) were significantly decreased in experimental groups when compared to the control group but there was no significant difference between experimental SOD groups. GFR was significantly greater in UW-MOD than in EC-MOD and tubular reabsorption of Na(+) was significantly greater in UW-MOD than in EC-MOD after 45 min of reperfusion. The release of LDH in the effluent and the urinary excretion of NAG were not significantly different after 24-h CS in the various experimental groups. The most relevant resonances determined by (1)HNMR spectroscopy were citrate, trimethylamine-N-oxide, lactate, acetate, and amino acids. Excretion of these markers was significantly different when compared to biochemical markers. A resonance (P) detected particularly in EC-MOD after 24-h CS was identified and well correlated to renal dysfunction. Histological study showed that ultrastructural damage and mitochondrial injury were more pronounced in the EC-MOD group.

CONCLUSION

These results show that retrieval condition influences renal medullary damage. NMR spectroscopy, which is a noninvasive and nondestructive technique, is more efficient in assessing renal damage than conventional histology and biochemical analysis.

Polyethylene stent blockage: a porcine model

BACKGROUND

Endoscopic insertion of biliary stents is a useful treatment for obstructive jaundice resulting from unresectable tumors of the pancreas and biliary tree. The main drawback is the recurrence of jaundice due to clogging. The aim of this study was to establish an experimental model of polyethylene stent clogging in large white pigs.

METHODS

A straight polyethylene stent of 5F (group I), 7F (group II) or 10F size (group III) was inserted in the common bile duct. Animals were killed at 2 months, or earlier if physical signs suggesting stent clogging occurred. Chemicophysical analysis of stent deposition combined stereomicroscopy and identification of the contents by means of Fourrier transform infrared spectroscopy. Bacteriologic analyses included identification of aerobic and anaerobic bacteria and measurement of beta-glucuronidase, lecithinase and lipase activities.

RESULTS

Physical signs suggesting stent obstruction or death occurred in 8 of 8 animals in group I, 11 of 12 in group II, and 2 of 8 in group III (p < 0.001). The proportion of mucoprotein in the stent contents tended to fall with increasing stent diameter (mean 82%, 58% and 47% for 5F, 7F and 10F, respectively), whereas wheat starch and calcium bilirubinate content increased with increasing stent diameter (9% and 4%, 18% and 10%, and 29% and 23% for 5F, 7 F, and 10F, respectively), although none of these differences were statistically significant. A variety of bacteria were cultured from the stent deposits, including anaerobic strains. Clostridium species were associated with the highest enzyme activities.

CONCLUSIONS

In this model the major component of early stent deposits was mucoprotein, and numerous aerobic and anaerobic bacteria were isolated. Formation of calcium bilirubinate was a late phenomenon and poorly related to bacterial enzymatic activities.

[Mycotic aneurysm of the splenic artery. A rare complication of surgically treated infectious endocarditis and its causative cardiac lesion]

The authors report the case of a 59 year old woman with mitral valve streptococcal endocarditis complicating rheumatic valvular disease with several metastatic septic complications. In addition to ocular and cerebral localisations, the patient developed a very rare mycotic aneurysm of the splenic artery. Mitral valve replacement was necessary because of severe mitral regurgitation with major dilatation of the left heart chambers. This surgery was performed under high dose heparin therapy. Large aneurysms of the splenic artery carry a high risk of rupture. This splenic artery aneurysm was treated in the same operative session as the valvular disease by a sternolaparotomy: the aneurysm was operated first of all, and then valvular replacement was performed. Three years later, the patient is well and cured of the endocarditis. To the authors' knowledge, this is the third report of mycotic aneurysm of the splenic artery and the first case combined with surgery of the infectious valvular disease and the gastro-intestinal artery aneurysm.

Renoprotective effects of trimetazidine against ischemia-reperfusion injury and cold storage preservation: a preliminary study

BACKGROUND

Initial ischemia-reperfusion injury is associated with organ retrieval, storage, and transplantation adversely affects early graft function and influences the development of chronic graft dysfunction. We have recently shown that the protective agent trimetazidine (TMZ) added to preservation solutions: Euro-collins (EC) and University of Wisconsin (UW) was efficient to protect kidneys from ischemia-reperfusion injury in an isolated perfused kidney model. We extended these observations to investigate the role of this drug in the development and progression of organ dysfunction in the autotransplant pig kidney model.

METHODS

Five experimental groups were studied. After 48-hr cold preservation, autotransplantation and immediate controlateral nephrectomy was then performed in group EC (EC+placebo (n=8), EC+TMZ (n=8), UW+placebo (n=7), and (UW+TMZ) (n=7) and compared with control group (uninephrectomized, n=4) during 14 days. Blood and urine samples were collected for the measurement of creatinine and blood urea nitrogen on postoperative days 1, 3, 5, 7, 11, and 14. Histological analysis was performed after reperfusion and at day 14.

RESULTS

Survivals were 100% in group B and D versus 42% in group A and 57% in group C. Urine production occurred earlier after autotransplantation from TMZ preserved kidneys than in placebo preserved groups. Peak creat and blood urea nitrogen was significantly greater in groups B and D than in groups A and C. TMZ was also efficient both to reduce ischemia-reperfusion injury and to decrease cellular infiltration.

CONCLUSION

These results support the beneficial effect of TMZ against ischemia-reperfusion injury and its early effects on grafts in the form of delayed graft function and decreased graft survival. In addition, TMZ reduces inflammatory cellular infiltration in the renal parenchyma.

Sacrococcygeal and transsacral epidural anesthesia in the laboratory pig: a model for experimental surgery

The laboratory piglet is currently the preferred animal for experimental digestive surgery. In order to ensure optimal perioperative analgesic control with motor blockade during surgery together with rapid postoperative recovery, epidural anesthesia techniques were developed in this animal. We report the anatomo-radiologic studies (10 animals) and clinical experiments (51 transplantations of the liver and the small intestine) which led to the refinement of this anesthesia. In laboratory piglets, epidural anesthesia by distal transsacral (S4-S5) or sacrococcygeal approach is possible in a reproducible manner. The localization of the injection site is simple and epidural space catheterisation is easy without risk for the dural sac which ends at S1-S2.

Anomalous pancreatico-biliary ductal union with cystic dilatation of the bile duct

We report, in an adult, an asymptomatic association between cystic dilation of the bile duct (type IV A in Todani's classification) and anomalous pancreatico-biliary ductal union (APBD) with stones in a long common channel. In APBD, the connection between the common bile duct and the main pancreatic duct is located outside the duodenal wall andis therefore not under the influence of the sphincter of Boyden. An abnormally long common channel is in excess of 15 mm. Two types of convergence anomalies are defined according to whether the bile duct opens into the main pancreatic duct (BP) or the main pancreatic duct into the bile duct (PB). In APBD, there is probably a reverse pressure gradient between the bile and pancreatic ducts, with regurgitation of pancreatic juice into the bile duct, repeated attacks of cholangitis, stenosis and cystic dilatation. A long common channel is associated with a higher incidence of carcinoma of the gall bladder of the bile duct.

[Technique for protecting the liver graft less tolerant than the small bowel to heat-induced ischemia in experimental liver + small bowel transplantation in swine]

Multivisceral and orthotopic liver/small bowel transplantations have been performed to treat patients with intestinal failure associated with liver failure induced by parenteral nutrition. The aim of this experimental study was to determine the experimental liver-small bowel harvesting and transplantation technique that achieves the best compromise between liver and intestine ischemia times in pigs. Initial portal revascularization of the liver which reduces the hepatic warm ischemia time after cold ischemia preparation of the graft immersed in lactated ringer's solution at 4 degrees C, reduce the risk of primary non function of the graft.

[Renal cancer and late pancreatic metastases. Apropos of 3 cases and review of the literature]

Renal cell carcinoma is a malignant epithelial tumour which can always give rise to metastases, usually situated in the lungs, bone and liver. In contrast, pancreatic metastases are exceptional and can occur late. The authors report three cases of metachronous pancreatic metastases, 1, 4 and 10 years after nephrectomy. The procedures performed consisted of Whipple procedure, tumour excision and total duodenopancreatectomy. Although rare when isolated to the pancreas, these metastases can justify even audacious pancreatic resection.

Ventilatory effects of laparoscopic cholecystectomy

BACKGROUND

During laparoscopic cholecystectomy the arterial-end-tidal CO2 gradient (Fa-ETCO2) has been variously shown to be unchanged, increased, decreased or even negative. The goal of this study was to evaluate Fa-ETCO2, and to determine the proper contribution of VECO2 and VA in regard to the increase of FETCO2.

METHODS

Ventilatory patterns were studied in 15 ASA 1-2 patients (mean age +/- SD: 48.5 +/- 15.0) undergoing laparoscopic cholecystectomy, with intraperitoneal CO2 insufflation limited to 12 mmHg, 15 degrees head-up position, during general anaesthesia and controlled ventilation. The following were studied before, during and after the pneumoperitoneum: FaCO2, FETCO2, nasopharyngeal temperature; dead space ventilation, and expired volumes using the Single Breath Test for CO2. VA was calculated as the alveolar fraction of expired VT multipled by the respiratory frequency.

RESULTS

During pneumoperitoneum it is shown that: 1) Fa-ETCO2 either decreases and becomes even negative (n = 8) (P < 0.01), or stays unchanged (n = 7), but never elevates; 2) VECO2 increases (peak value: +22.6%) (P < 0.01); 3) VA is unchanged, and 4) dead space ventilation, determined in 7 patients, remains unchanged.

CONCLUSION

We conclude that only exogenous CO2 loading, and not VA, can explain such increase in FETCO2 and FaCO2, in cases of limited CO2 insufflating pressure in ASA 1-2 patients.

Anatomic and radiologic bases of combined transplantation of liver and small intestine in the pig

In order to assess the tolerance induced by hepatic transplantation in a multivisceral graft, a model of a transplant combining the liver and small intestine was developed in the pig, using animals of Large White Isogroup O, typed in the system of major incompatibility as "Swine lymphocyte antigen" (SLA), whose weight varied from 30 to 40 kg. In order to limit the duration of warm ischemia, dissection of the graft was performed on the donor animal with respect for the following anatomic features: absence of intestinal attachment to the posterior parietal peritoneum, anti-clockwise torsion of 360 degrees of the intestine around the superior mesenteric a. with the small intestine convolutions on the right and the colonic helix on the left. The bifid pancreas follows this rotation and its resection must respect the vascularisation of the proximal small intestine; the hepatic a. arises from a common trunk with a gastrosplenic branch of the aorta between the crura of the diaphragm and travels sagittally from behind forward toward the liver pedicle, which it reaches ar the upper border of the duodenum; the hepatic a. and its branches are dorsal in relation to the portal vein; the hepatic arterial distribution follows a right-left and antero-posterior systematisation for the six hepatic lobes of this quadruped animal.

[Human ontogeny of the left colon. Fetal stage]

Foetal evolution of bowel is the result of unequal growth of its segments and abdominal constraint of pressure. Caecum and appendix on the cranial and right side of intestine torsion differentiate colic anlage. Left colon observations in 20 foetus reveal a dorsal peritoneal fusion between 12 and 17 weeks: Progressive growth of left colon and meso, without dorsal fixation, beyond left kidney and subrenal gland. First mesocolon fixation at the left kidney. A tunnel persist between this fusion and the primitive mesocolon root. Radial advance of peritoneal fusion up to sigmoid mesocolon, with disappearance of the tunnel. Peritoneal fusion confirmed by histology.

[Arterial risks in celiosurgery]

It is important to recognize exceptional vascular events in celiosurgery because of their gravity. Most occur during pneumoperitoneal manoeuvres using a Palmer needle and rarely at the insertion of the first trocar. We performed a tomodensitometric study in 200 subjects free of abdominal pathology in order to determine the distance from the umbilicus to the aortic bifurcation, their projection over the spine and the superficial relations of the large vessels to the cutaneous umbilical cover. Generally, the projections of the umbilicus, and also the aortic bifurcation, lie over L4. The distance between the skin and the large retroperitoneal vesses is generally equal to one-third of the antero-posterior abdominal diameter. In thin subjects with a flat abdomen however, this distance may be smaller, even less than 3 cm. These findings emphasize the importance of "safety" manoeuvres during celiosurgery, especially during the learning period.

[Volvulus of the superior mesenteric area and congenital variation of the colonic fixation. Human Ontogenesis and Physiopathology. Apropos of a case in an adolescent]

Volvulus of the superior mesenteric territory involving the left and transverse colon is rare. Congenital variations of intestinal fixation have been implicated. We report a case observed in an adolescent which illustrates this hypothesis. There was a fixation of pancreatosplenic region and the left colic angle. The duodenopancreas and the right, transverse and left colon were mobile. Human ontogenesis of the colon could provide a pathophysiologic explanation. During foetal development, the intestine results from unequal growth of the different segments which undergo pressure from the different intra-abdominal contents. The fixation of the different parts of the intestine are independent from each other. Specific circumstances are required for variations in congenital fixation of the colon to led to late events responsible for mechanical volvulus.

[Follow-up of elderly patients previously treated for uncomplicated acute lithiasic cholecystitis]

Surgery is usually indicated in elderly patients with acute lithiasic cholecystitis although single antibiotics are often used for patients over 75 with complex medical histories and major visceral lesions. In our series of 45 patients, no new biliary pathology was seen in 26 (57.8%) after a mean follow-up of 40 months. In 15 patients, acute cholecystitis recurred and in 4 a stone found in the common bile duct. No deaths were associated with biliary pathology. While antibiotics appear to have an immediate beneficial effect, medium and long term results are mediocre. Percutaneous cholecystectomie however would be a satisfactory technique for external drainage even though mortality related to other pathologies is high.