Effects of acute and sub-acute hypobaric hypoxia on oxidative stress: a field study in the Alps.

PURPOSE: High altitude results in lower barometric pressure and hence partial pressure of O2 decrease can lead to several molecular and cellular changes, such as generation of reactive oxygen species (ROS). Electron Paramagnetic Resonance technique was adopted in the field, to evaluate the effects of acute and sub-acute hypobaric hypoxia (HH) on ROS production by micro-invasive method. Biological biomarkers, indicators of oxidative stress, renal function and inflammation were investigated too. METHODS: Fourteen lowlander subjects (mean age 27.3 ± 5.9 years) were exposed to HH at 3269 m s.l. ROS production, related oxidative damage to cellular components, systemic inflammatory response and renal function were determined through blood and urine profile performed at 1st, 2nd, 4th, 7th, and 14th days during sojourn. RESULTS: Kinetics of changes during HH exposition showed out significant (range p < 0.05-0.0001) increases that at max corresponds to 38% for ROS production rate, 140% for protein carbonyl, 44% for lipid peroxidation, 42% for DNA damage, 200% for inflammatory cytokines and modifications in renal function (assessed by neopterin concentration: 48%). Conversely, antioxidant capacity significantly (p < 0.0001) decreased - 17% at max. CONCLUSION: This 14 days in-field study describes changes of oxidative-stress biomarkers during HH exposure in lowlanders. The results show an overproduction of ROS and consequent oxidative damage to protein, lipids and DNA with a decrease in antioxidant capacity and the involvement of inflammatory status and a transient renal dysfunction. Exposure at high altitude induces a hypoxic condition during acute and sub-acute phases accompanied by molecular adaptation mechanism indicating acclimatization.

Ileal pouch-anal anastomosis with fluorescence angiography: a case-matched study.

AIM: An anastomotic leak in ileoanal pouch surgery may lead to pouch failure. Constructing a tension-free ileal pouch-anal anastomosis (IPAA) reduces this risk but can be technically challenging, balancing pouch vascularization with ileal mesenteric length and site of vessel ligation. Fluorescence angiography (FA) may help the clinician make a more balanced judgement. METHODS: Thirty-two patients undergoing minimally invasive completion proctectomy with FA-guided IPAA at two academic centres were matched and compared on a 1:1 basis to a historical group undergoing the same procedure without the use of this technique. RESULTS: Ligation of the ileocolic vessels was safely performed in 15/32 (47%) of FA patients compared with 5/32 (16%) of historical controls. One patient underwent intra-operative IPAA reconstruction after FA detected ischaemia. No anastomotic leak occurred with FA but there was only one in the historical controls (P = 0.31). The postoperative complication rate was similar between the two groups (P = 0.60). CONCLUSION: FA is applicable to IPAA surgery and may help to reduce perfusion-related anastomotic leaks. A prospective randomized trial is warranted.

Molecular heterogeneity and prognostic implications of synchronous advanced colorectal neoplasia.

BACKGROUND: It is uncertain whether synchronous colorectal cancers (S-CRCs) preferentially develop through widespread DNA methylation and whether they have a prognosis worse than solitary CRC. As tumours with microsatellite instability (MSI) may confound the effect of S-CRC methylation on outcome, we addressed this issue in a series of CRC characterised by BRAF and MS status. METHODS: Demographics, clinicopathological records and disease-specific survival (DSS) were assessed in 881 consecutively resected CRC undergoing complete colonoscopy. All tumours were typed for BRAF(c.1799T>A) mutation and MS status, followed by search of germ-line mutation in patients with MSI CRC. RESULTS: Synchronous colorectal cancers (50/881, 5.7%) were associated with stage IV microsatellite-stable (MSS) CRC (19/205, 9.3%, P=0.001) and with HNPCC (9/32, 28%, P<0.001). BRAF mutation (60/881, 6.8%) was associated with sporadic MSI CRC (37/62, 60%, P<0.001) but not with S-CRC (3/50, 6.0%, P=0.96). Synchronous colorectal cancer (HR 1.82; 95% CI 1.15-2.87; P=0.01), synchronous advanced adenoma (HR 1.81; 95% CI 1.27-2.58; P=0.001), and BRAF(c.1799T>A) mutation (HR 2.16; 95% CI 1.25-3.73; P=0.01) were stage-independent predictors of death from MSS CRC. Disease-specific survival of MSI CRC patients was not affected by S-CRC (HR 0.74; 95% CI 0.09-5.75; P=0.77). CONCLUSION: Microsatellite-stable CRCs have a worse prognosis if S-CRC or synchronous advanced adenoma are diagnosed. The occurrence and the enhanced aggressiveness of synchronous MSS advanced neoplasia are not associated with BRAF mutation.

Early expression of the fractalkine receptor CX3CR1 in pancreatic carcinogenesis.

BACKGROUND: In pancreatic ductal adenocarcinoma (PDAC), fractalkine receptor CX3CR1 contributes to perineural invasion (PNI). We investigated whether CX3CR1 expression occurs early in PDAC and correlates with tumour features other than PNI. METHODS: We studied CX3CR1 and CX3CL1 expression by immunohistochemistry in 104 human PDAC and coexisting Pancreatic Intraepithelial Neoplasia (PanIN), and in PdxCre/LSL-Kras(G12D) mouse model of PDAC. CX3CR1 expression in vitro was studied by a spheroid model, and in vivo by syngenic mouse graft of tumour cells. RESULTS: In total, 56 (53.9%) PDAC expressed CX3CR1, 70 (67.3%) CX3CL1, and 45 (43.3%) both. CX3CR1 expression was independently associated with tumour glandular differentiation (P=0.005) and PNI (P=0.01). Pancreatic Intraepithelial Neoplasias were more frequently CX3CR1+ (80.3%, P<0.001) and CX3CL1+ (86.8%, P=0.002) than matched cancers. The survival of PDAC patients was better in those with CX3CR1+ tumour (P=0.05). Mouse PanINs were also CX3CR1(+) and -CL1(+). In vitro, cytokines significantly increased CX3CL1 but not CX3CR1 expression. Differently, CX3CR1 was upregulated in tumour spheroids, and in vivo only in well-differentiated tumours. CONCLUSION: Tumour differentiation, rather than inflammatory signalling, modulates CX3CR1 expression in PanINs and PDAC. CX3CR1 expression pattern suggests its early involvement in PDAC progression, outlining a potential target for interfering with the PanIN transition to invasive cancer.

Intraoperative ultrasonographic detection of communicating veins between adjacent hepatic veins during hepatectomy for tumours at the hepatocaval confluence.

BACKGROUND: The presence of communicating veins between adjacent hepatic veins may allow parenchyma-sparing hepatectomy. Taking advantage of improvements in ultrasound technology, such as e-flow modality, a study of the presence of communicating veins was conducted in patients with hepatic tumours at the caval confluence. METHODS: Consecutive patients undergoing surgery between October 2007 and December 2009 for hepatic tumours in contact with or invading a hepatic vein at its caval confluence were included. Communicating vein mapping by means of e-flow intraoperative ultrasonography (EF-IOUS) was carried out. RESULTS: A total of 20 patients were enrolled. Communicating veins between adjacent hepatic veins or with the inferior vena cava were detected in 16 patients. The median number of communicating veins was 1 (range 0-5). The total number of lesions removed was 126 (range 1-46). In 11 of 12 patients requiring resection of a hepatic vein, communicating veins enabled a parenchyma-sparing procedure to be performed. No patient had a formal major hepatectomy. There was no postoperative mortality or major morbidity. CONCLUSION: EF-IOUS estimation of the frequency of communicating veins between adjacent hepatic veins suggests that such veins are common. This may facilitate parenchyma-sparing procedures in patients with hepatic tumours encroaching on major hepatic veins.

Laparoscopic liver resections for hepatocellular carcinoma. Is it a feasible option for patients with liver cirrhosis?

BACKGROUND: Laparoscopic surgery has gained growing acceptance, but this does not hold for laparoscopic surgery of the liver, above all for patients with hepatocellular carcinoma (HCC) and cirrhosis. This approach mainly includes diagnostic procedures and interstitial therapies. However, we believe there is room for laparoscopic liver resections in well-selected cases. The aim of this study is to assess: (a) the risk of intraoperative bleeding and postoperative complications, (b) the safety and the respect of oncological criteria, and (c) the potential benefit of laparoscopic ultrasound in guiding liver resection. METHODS: A prospective study of laparoscopic liver resections for hepatocellular carcinoma was undertaken in patients with compensated cirrhosis. Hepatic involvement had to be limited and located in the left or peripheral right segments (segments 2-6), and the tumor had to be 5 cm or smaller. Tumor location and its transection margins were defined by laparoscopic ultrasound. RESULTS: From January 1997, 22 out of 250 patients with HCC (9%) underwent laparoscopic liver resections. The mean patient age was 61.4 years (range, 50-79 years). In three patients, conversion to laparotomy was necessary. The laparoscopic resections included five bisegmentectoies (2 and 3), nine segmentectomies, two subsegmentectomies and three nonanatomical resections for extrahepatic growing lesions. The mean operative time, including laparoscopic ultrasonography, was 199 +/- 69 min (median, 220; range, 80-300). Perioperative blood loss was 183 +/- 72 ml (median, 160; range, 80-400 ml). There was no mortality. Postoperative complications occurred in two out of 19 patients: an abdominal wall hematoma occurred in one patient and a bleeding from a trocar access in the other patient requiring a laparoscopic re-exploration. Mean hospital stay of the whole series was 6.5 +/- 4.3 days (median, 5; range, 4-25), while the mean hospital stay of the 19 laparoscopic patients was 5.4 +/- 1 (median, 5; range, 4-8). CONCLUSION: Laparoscopic treatment should be considered in selected patients with HCC and liver cirrhosis in the left lobe or segments 5 and 6 of the liver. It is clear that certain types of laparoscopic resection are feasible and safe when carried out by adequately skilled surgeons with appropriate instruments.

Evaluation of the MDACC clinical classification system for pancreatic cancer patients in an European multicenter cohort.

BACKGROUND: The MDACC group recommends to extend the current borderline classification for pancreatic cancer into three groups: type A patients with resectable/borderline tumor anatomy, type B with resectable/borderline resectable tumor anatomy and clinical findings suspicious for extrapancreatic disease and type C with borderline resectable and marginal performance status/severe pre-existing comorbidity profile or age>80. This study intents to evaluate the proposed borderline classification system in a multicenter patient cohort without neoadjuvant treatment. METHODS: Evaluation was based on a multicenter database of pancreatic cancer patients undergoing surgery from 2005 to 2016 (n = 1020). Complications were classified based on the Clavien-Dindo classification. χ2-test, Kaplan-Meier estimator and Cox regression hazard model were used for statistical analysis. RESULTS: Most patients (55.1%) were assigned as type A patients, followed by type C (35.8%) and type B patients (9.1%). Neither the complication rate, nor the mortality rate revealed a correlation to any subgroup. Type B patients had a significant worse progression free (p < 0.001) and overall survival (p = 0.005). Type B classification was identified as an independent prognostic marker for progression free survival (p = 0.005, HR 1.47). CONCLUSION: The evaluation of the proposed classification in a cohort without neoadjuvant treatment did not justify an additional medical borderline subgroup. A new subgroup based on prognostic borderline patients might be the main target group for neoadjuvant protocols in future.

Impact of intraoperative ultrasonography in laparoscopic liver surgery.

BACKGROUND: Laparoscopic surgery has gained growing acceptance, but this does not hold for laparoscopic surgery of the liver. This mainly includes diagnostic procedures, interstitial therapies, and treatment of liver cysts. However, the authors believe there is room for a laparoscopic approach to the liver in selected cases. METHODS: A prospective study of laparoscopic liver resections was undertaken with patients who had preoperative diagnoses of benign lesion and hepatocellular carcinoma with compensated cirrhosis. The inclusion criteria required that hepatic involvement be limited and located in the left or peripheral right segments (segments 2-6), and that the tumor be 5 cm or smaller. The location of the tumor and its transection margin were defined by laparoscopic ultrasound (LUS). RESULTS: From December 1996, 17 (5%) of 313 liver resections were included in the study. There were 5 benign lesions and 12 hepatocellular carcinomas in cirrhotic patients. The mean age of the study patients was 59 years (range, 29-79 years). The LUS evaluation identified the presence of new hepatocellular carcinoma nodules in two patients (17%). The resections included 1 bisegmentectomy, 8 segmentectomies, 3 subsegmentectomies, and 3 nonanatomic resections. The mean operative time, including laparoscopic ultrasonography, was 156 +/- 50 min (median, 150 min; range, 60-250 min), and the perioperative blood loss was 190 +/- 97 ml. There was no mortality. Conversion to laparotomy was necessary for two patients. Postoperative complications were experienced by 3 of 15 patients, all of them cirrhotics. One of the patients had a wall hematoma, and the remaining two patients had bleeding from a trocar access requiring a laparoscopic reexploration. The mean hospital stay for the whole series was 6.9 +/- 4.9 days (median, 6 days; range, 2-25 days) and 5.6 +/-1.4 days (median, 6 days; range, 2-8 days) for the 15 laparoscopic patients. CONCLUSION: Laparoscopic treatment should be considered for selected patients with benign and malignant lesions in the left lobe or frontal segments of the liver. Evaluation by LUS is indispensable to guarantee precise determination of the segmental tumor location and the relationship of the tumor to adjacent vascular or biliary structures, excluding adjacent or adjunctive new lesions. The evolution of laparoscopic hepatectomies probably will depend on the development of new techniques and instrumentations.

Liver resection for primary hepatic neuroendocrine tumours: report of three cases and review of the literature.

Primary neuroendocrine tumours are rare especially in the liver, which is more often site of metastatic tumours. We report three cases of primary hepatic neuroendocrine tumours, which underwent hepatic resection. Review of the diagnostic and therapeutic approaches to these tumours are discussed.

Laparoscopic ultrasound-guided resection of gastric submucosal tumors.

BACKGROUND: The laparoscopic resection of gastric stromal tumors is being performed with increased frequency. Wedge resection of anterior wall lesions is generally performed. The treatment of posterior wall lesions is still controversial. METHODS: We report three cases of gastric submucosal tumors treated by a laparoscopic wedge resection of the stomach. All lesions were localized anterior gastric wall by intraoperative ultrasound on the. In the first patient the resection was performed with an endoscopic stapler; in the other patients, ultrasonic coagulation in association with an intracorporeal suture has been used. RESULTS: All patients were successfully treated laparoscopically; there were no conversions to open surgery. In all cases the operative course was uneventful. The postoperative hospital stay ranged from 6 to 8 days. CONCLUSIONS: The results suggest that laparoscopic surgery is an adequate strategy for gastric submucosal neoplasms including gastrointestinal stromal tumors (GIST). Intraoperative ultrasound is very useful in the selection of the technical approach with or without the endoscopic stapler.

Parenchyma-sparing surgery for pancreatic endocrine tumors.

Enucleation (EN) and middle pancreatectomy (MP) have been proposed as a treatment for G1 and G2 pancreatic neuroendocrine tumors (PNET). The aim of this study is to analyze the outcomes of parenchyma-sparing surgery (PSS) for PNET in an Italian high-volume center. All patients with a histological diagnosis of PNET who underwent surgical resection in our center between January 2010 and January 2016 were included in the study. Demographic, perioperative, and discharge data were collected in a prospective database. Follow-up was considered until March 31, 2016. 99 patients were included. PSS was performed in 22 cases (22.2 %), 18 EN (82 %), and 4 MP (18 %). 89.8 % patients were staged with CT scan, 69.6 % with endoscopic ultrasonography, 48.4 % with MRI, and 47.4 % with 68Ga-PET. Pre-operative histological diagnosis was obtained in 68.6 %. Most of PSS tumors were G1 (n = 15; 68 %) and there were no G3. Nodal sampling was performed in every PSS. Only two patients showed nodal metastatic disease. The median post-operative length of stay was 7 days after PSS. Eleven (50 %) of these patients developed a complication; two (18.2 %) were major complications. Pancreatic fistula developed in ten patients (45.5 %); two (20 %) were type B. There were no type C fistula and no re-operations after PSS. Readmission rate was 9 %. All patients submitted to PSS are alive and free of recurrence. PSS is a safe technique for G1 and G2 PNETs, but it has to be conducted in experienced centers and an extensive nodal sampling and a long follow-up are required for the best oncologic outcome.

Utility of the hooking technique for cases of major hepatectomy.

Currently, resective hepatic surgery should be considered an echoguided surgical procedure to guarantee conservative but radical resections. A simple and original technique guided by intraoperative ultrasonography, termed the "hooking technique," had been described previously. It enables the ligation sites of the intrahepatic vessels during systematic segmentectomy to be chosen precisely. This report describes a further application of this technique to allow safe ligation of portal vein main branches invaded by tumor thrombi during major hepatectomies.

Technical tricks for radical but conservative liver resection. The ultrasound guidance.

Rate of major resection is still high in most surgical institutions due to fear of incomplete tumor removal: this is in spite mortality and major morbidity of major hepatectomies, particularly in cirrhotic are still not negligible. Intraoperative ultrasonography (IOUS), when used not only for tumor staging but also for resection guidance, minimises the rate of major hepatectomies maintaining treatment radicality. Maintaining this policy, the rate of major resection in our experience is 15% if major hepatectomy is classified as removal of at least 1 sector or 2 adjacent segments, and 5% if we consider major resections only those which include at least 3 segments. This policy has allowed us a safe surgical approach with no mortality and minimal major morbidity and effective local treatment with no tumor relapses at the site of the resection after a mean follow-up of 18 months. Tricks for safe and radical IOUS-guided liver resections are here discussed.

Efficacy of octreotide in the prevention of pancreatic fistula after elective pancreatic resections: a prospective, controlled, randomized clinical trial.

BACKGROUND: A prospective, randomized controlled clinical trial was conducted in 33 Italian surgical departments with the aim of evaluating the efficacy of octreotide in the prevention of pancreatic fistula after elective pancreatic resections. METHODS: Between July 1990 and May 1992, 278 patients were enrolled in the study. Fifty-four dropped out because of unresectable disease and six were excluded because of protocol violation; the remaining 218 were randomly assigned to the octreotide group (n = 111) or to the placebo group (n = 107). There were 131 men and 87 women with a mean age of 58.2 +/- 11.7 yrs. Pancreaticoduodenectomy was the most common operation performed (n = 143), sixty-four percent of patients had a pancreatic or periampullary cancer; chronic pancreatitis accounted for 8.2% of cases. RESULTS: Mortality rate was 6.9%. A pancreatic fistula occurred in 31 patients (14.2%), 9% in the octreotide group and 19.6% in the placebo group (p < 0.05). Morbidity rate was significantly lower in the octreotide (21.6%) than in the placebo group (36.4%) (p < 0.05). When specific pancreatic complications were grouped together and evaluated, they occurred less frequently in the treated (15.3%) than in the placebo group (29.9%) (p < 0.05). CONCLUSIONS: Octreotide was able to reduce significantly the incidence of pancreatic fistula after elective pancreatic resections.

Intraoperative ultrasound during thoracoscopic procedures for solitary pulmonary nodules.

BACKGROUND: Traditional nonoperative diagnostic approaches to the solitary pulmonary nodule (bronchoscopy and percutaneous needle biopsy) can be inconclusive. Video-assisted thoracic surgery (VATS) provides a minimally invasive way to diagnose and treat these nodules. We evaluated the use of a dedicated intraoperative ultrasound probe as an aid in localization of small pulmonary nodules during VATS. METHODS: An intraoperative ultrasound examination during a thoracoscopic procedure was performed on 18 patients to localize deep pulmonary nodules less than 20 mm in diameter without a definitive diagnosis by preoperative imaging techniques. RESULTS: In the 18 patients, all nodules were successfully identified by intraoperative ultrasound. A definitive pathologic diagnosis was obtained from thoracoscopic biopsy or resection. The final diagnoses were primary lung cancer in 5 patients, metastatic lesions in 4 patients, hamartoma or chondroma in 4, granuloma in 3, and interstitial fibrosis in 2 patients. CONCLUSIONS: In our experience, intraoperative ultrasound can safely and effectively localize invisible or nonpalpable pulmonary nodules at the time of thoracoscopy. This may help surgeons perform minimally invasive lung resections with clear surgical margins.

Pancreatic polypeptide response to food and cerulein in patients with total gastrectomy.

In order to investigate the intestinal phase of pancreatic polypeptide (PP) release, the hormonal response to food and cerulein was measured in 19 patients with truncal vagotomy and total gastrectomy (10 with simple esophagojejunal anastomosis and 9 with an additional duodenojejunal anastomosis) and in 7 healthy subjects. After gastrectomy, the early peak of the physiologic biphasic PP response to food was lost but the late predominant phase was unchanged so that the overall postprandial release of the hormone was not significantly lowered. Gastrectomized patients with duodenal bypass had postprandial serum levels only slightly lower than those of patients with preserved duodenal transit of food. Serum PP response to cerulein stimulation was significantly lower in vagotomized patients than in healthy subjects. However, in operated patients as well as in controls, cerulein infusion did induce a rapid increase of plasma PP, followed by persistently elevated levels. The PP response to cerulein was abolished by atropine pretreatment. Our findings indicate that the intestinal phase of meal-stimulated PP response is not dependent on the integrity of vagal pancreatic innervation and that the preservation of the duodenal transit of food after total gastrectomy is not crucial for the maintenance of the enteroinsular axis.