Surgical therapy of celiac axis and superior mesenteric artery syndrome

INTRODUCTION

Compression syndromes of the celiac artery (CAS) or superior mesenteric artery (SMAS) are rare conditions that are difficult to diagnose; optimal treatment remains complex, and symptoms often persist after surgery. We aim to review the literature on surgical treatment and postoperative outcome in CAS and SMAS syndrome.

METHODS

A systematic literature review of medical literature databases on the surgical treatment of CAS and SMAS syndrome was performed from 2000 to 2022. Articles were included according to PROSPERO guidelines. The primary endpoint was the failure-to-treat rate, defined as persistence of symptoms at first follow-up.

RESULTS

Twenty-three studies on CAS (n = 548) and 11 on SMAS (n = 168) undergoing surgery were included. Failure-to-treat rate was 28% for CAS and 21% for SMAS. Intraoperative blood loss was 95 ml (0-217) and 31 ml (21-50), respectively, and conversion rate was 4% in CAS patients and 0% for SMAS. Major postoperative morbidity was 2% for each group, and mortality was described in 0% of CAS and 0.4% of SMAS patients. Median length of stay was 3 days (1-12) for CAS and 5 days (1-10) for SMAS patients. Consequently, 47% of CAS and 5% of SMAS patients underwent subsequent interventions for persisting symptoms.

CONCLUSION

Failure of surgical treatment was observed in up to every forth patient with a high rate of subsequent interventions. A thorough preoperative work-up with a careful patient selection is of paramount importance. Nevertheless, the surgical procedure was associated with a beneficial risk profile and can be performed minimally invasive.

Considerations and barriers to starting a new HAI pump program: an international survey of the HAI Consortium Research Network

BACKGROUND

Widespread implementation of HAI pump chemotherapy has been limited by logistic and feasibility concerns. Recent studies demonstrating excellent outcomes have fueled renewed enthusiasm and multiple new programs have emerged. This survey aims to identify barriers critical to establish a successful HAI program.

METHODS

Using SurveyMonkey™, a 17-question survey assessing factors required for establishing a successful program was developed by 12 HAI Consortium Research Network (HCRN) surgical oncologists. Content analysis was used to code textual responses. Frequency of categories and average rank scores for each choice were calculated.

RESULTS

Twenty-eight HCRN members responded to the survey. Implementation time varied, with 15 institutions requiring less than a year. Most programs (n = 17) became active in the past 5 years. Medical and surgical oncology were ranked most important for building a program (average ranking scores: 7.96 and 6.59/8). Administrative or regulatory approval was required at half of the institutions. The top 3 challenges faced when building a program were related to regulatory approval (6.65/9), device/equipment access (6.33/9), and drug (FUDR) access (6.25/9).

CONCLUSION

Development of successful programs outside of historically established centers is feasible and requires a multidisciplinary team. Future collaborative efforts are critical for sustainability of safe/effective new programs.

Robotic distal pancreatectomy, a novel standard of care? First benchmark values for surgical outcomes from 14 international expert centers

Objective

Robotic distal pancreatectomy (DP) is emerging as the preferred treatment for body and tail tumors of the pancreas. To enable conclusive comparisons with the standard open or laparoscopic approaches and robotic surgery among centers, novel benchmark outcome values are urgently needed. Therefore, the aim of this study was to identify benchmark values from expert centers beyond the learning curve.

Methods

This multicenter study analyzed outcomes from consecutive patients undergoing robotic DP for resectable malignant or benign lesions from 14 international expert centers. After the learning curve, defined as the first 10 cases of robotic DP, all consecutive patients were included from the start of the program up to June 2020 with a minimum follow-up of 1 year. Benchmark patients were those without significant comorbidities including obesity (BMI >35 kg/m2) cardiac disease, chronic pulmonary disease.

Benchmark cutoff values were derived from the 75th or the 25th percentile of the median values of all benchmark centers.

Results

After reaching the learning curve, 289 (47%) of a total of 614 consecutive patients qualified as benchmark cases. The proportion of benchmark patients varied between 24%-64% per center. Benchmark cut-offs showed a low 6 month- postoperative mortality (<0.6%), but high overall morbidity (<58.3%). Benchmark cutoffs for operative time (<300 min), conversion rate (<3%), clinically relevant pancreatic fistulas (<26.9%), CCI at 90-days (<14.8), hospital stay (<7 days) and readmission rate (<22.9%). Benchmark cut-offs for complications remained unchanged after 3 months follow-up. For ductal adenocarcinoma benchmark cutoffs for number of lymph nodes were > 19 with an R0 resection rate of > 85%, and an overall survival of >86% and >52% after 1- and 5-years, respectively. Centers with a low cohort of benchmark patients (more difficult cases) had less clinically relevant pancreatic fistula (9% vs. 23%) and less overall complications (32% vs. 48%).

Conclusion

This benchmark analysis sets novel reference values for robotic DP, indicating favorable outcomes as compared to laparoscopic and open DP. These references values may serve for quality control of surgery in centers embarking in robotic DP, and include the procedure in the standard of care.

Phase Ib dose-escalation study of the hypoxia-modifier myo-inositol trispyrophosphate in patients with hepatopancreatobiliary tumors

Objective

Hypoxia is present in most solid tumors and acts as a driver of malignancy. Myo-inositol trispyrophosphate (ITPP) is a novel re-oxygenating compound without apparent toxicity. In preclinical models, it potentiates the efficacy of subsequent chemotherapy through vascular normalization. We sought to assess the safety, tolerability, and preliminary efficacy of ITPP.

Methods

In this monocentric, open-label, dose-escalation study following a 3+3 design, eligible patients with advanced primary and secondary hepatopancreatobiliary tumors received nine 8-h infusions of ITPP during 3 weeks across eight dose levels (1866–14,500 mg/m2/dose), followed by standard chemotherapy. Primary endpoints were safety and tolerability. Secondary endpoints were pharmacokinetics and estimation of efficacy based on radiological responses and angiogenic serum markers. Registration number: NCT02528526.

Results

From April 2015 to July 2018, a total of 28 enrolled patients were assessed for the primary endpoints. ITPP was safe up to single doses of 12,390 mg/m2, and 32 ITPP-related adverse events occurred: 19 (67.8%) hypercalcemia, 5 (17.8%) hyponatremia, and 4 (14.2%) hypomagnesemia. Following ITPP monotherapy, 52% of patients displayed morphological disease stabilization. Following subsequent chemotherapy, 10% showed a partial response, and 60% had stable disease. Angiogenic markers were decreased in 60% after ITPP and tended to correlate with responses and survival after chemotherapy.

Conclusion

Administration of ITPP is safe up to 12,390 mg/m2 with favorable pharmacokinetics. Preliminary translational efficacy data show decreased angiogenic markers, which might indicate an anti-hypoxic effect and enhancement of chemotherapy through ITPP.

Epidural analgesia and perioperative kidney function after major liver resection

BACKGROUND

Epidural analgesia (EDA) is a common analgesia regimen in liver resection, and is accompanied by sympathicolysis, peripheral vasodilatation and hypotension in the context of deliberate intraoperative low central venous pressure. This associated fall in mean arterial pressure may compromise renal blood pressure autoregulation and lead to acute kidney injury (AKI). This study investigated whether EDA is a risk factor for postoperative AKI after liver surgery.

METHODS

The incidence of AKI was investigated retrospectively in patients who underwent liver resection with or without EDA between 2002 and 2012. Univariable and multivariable analyses were performed including recognized preoperative and intraoperative predictors of posthepatectomy renal failure.

RESULTS

A series of 1153 patients was investigated. AKI occurred in 8·2 per cent of patients and was associated with increased morbidity (71 versus 47·3 per cent; P = 0·003) and mortality (21 versus 0·3 per cent; P <  0·001) rates. The incidence of AKI was significantly higher in the EDA group (10·1 versus 3·7 per cent; P = 0·003). Although there was no significant difference in the incidence of AKI between patients undergoing minor hepatectomy with or without EDA (5·2 versus 2·7 per cent; P = 0·421), a substantial difference in AKI rates occurred in patients undergoing major hepatectomy (13·8 versus 5·0 per cent; P = 0·025). In multivariable analysis, EDA remained an independent risk factor for AKI after hepatectomy (P = 0·040).

CONCLUSION

EDA may be a risk factor for postoperative AKI after major hepatectomy.

Liver transplantation in recipients receiving renal replacement therapy: outcomes analysis and the role of intraoperative hemodialysis

The Model for End-Stage Liver Disease (MELD) system has dramatically increased the number of recipients requiring pretransplant renal replacement therapy (RRT) prior to liver transplantation (LT). Factors affecting post-LT outcomes and the need for intraoperative RRT (IORRT) were analyzed in 500 consecutive recipients receiving pretransplant RRT, including comparisons among recipients not receiving IORRT (No-IORRT, n = 401), receiving planned IORRT (Pl-IORRT, n = 70), and receiving emergent, unplanned RRT after LT initiation (Em-IORRT, n = 29). Despite a median MELD of 39, overall 30-day, 1-, 3- and 5-year survivals were 93%, 75%, 68% and 65%, respectively. Em-IORRT recipients had significantly more intraoperative complications (arrhythmias, postreperfusion syndrome, coagulopathy) compared with both No-IORRT and Pl-IORRT and greater 30-day graft loss (28% vs. 10%, p = 0.004) and need for retransplantation (24% vs. 10%, p = 0.099) compared with No-IORRT. A risk score based on multivariate predictors of IORRT accurately identified recipients with chronic (sensitivity 84%, specificity 72%, concordance-statistic [c-statistic] 0.829) and acute (sensitivity 93%, specificity 61%, c-statistic 0.776) liver failure requiring IORRT. In this largest experience of LT in recipients receiving RRT, we report excellent survival and propose a practical model that accurately identifies recipients who may benefit from IORRT. For this select group, timely initiation of IORRT reduces intraoperative complications and improves posttransplant outcomes.

Current surgical management of hilar and intrahepatic cholangiocarcinoma: the role of resection and orthotopic liver transplantation

Cholangiocarcinoma (CCA) is a rare but devastating malignancy that presents late, is notoriously difficult to diagnose, and is associated with a high mortality. Surgical resection is the only chance for cure or long-term survival. The treatment of CCA has remained challenging because of the lack of effective adjuvant therapy, aggressive nature of the disease, and critical location of the tumor in close proximity to vital structures such as the hepatic artery and the portal vein. Moreover, the operative approach is dictated by the location of the tumor and the presence of underlying liver disease. During the past 4 decades, the operative management of CCA has evolved from a treatment modality that primarily aimed at palliation to curative intent with an aggressive surgical approach to R0 resection and total hepatectomy followed by orthotopic liver transplantation.

Systematic review and meta-analysis of interferon after curative treatment of hepatocellular carcinoma in patients with viral hepatitis

BACKGROUND

A combined antiviral and tumoricidal effect of interferon (IFN) is assumed to occur after resection or ablation of hepatocellular carcinoma (HCC).

METHODS

An electronic search of the Medline, Embase and Central databases from January 1998 to October 2007 was conducted to identify randomized controlled trials evaluating adjuvant effects of IFN after curative treatment of HCC. A meta-analysis was performed to estimate the effects of IFN on 2-year outcome.

RESULTS

Seven trials enrolling a total of 620 patients were included in the meta-analysis. Adjuvant treatment with IFN significantly reduced the 2-year mortality rate after curative treatment of HCC, with a pooled risk ratio of 0.65 (95 per cent confidence interval 0.52 to 0.80); P < 0.001) in absence of any significant heterogeneity (I(2) = 0 per cent, P = 0.823 for chi(2)). The effect on reduction of tumour recurrence was less pronounced but still significant (pooled risk ratio 0.86 (95 per cent c.i. 0.76 to 0.97); P = 0.013). IFN had to be discontinued in 8-20 per cent of patients.

CONCLUSION

IFN has a significant beneficial effect after curative treatment of HCC in terms of both survival and tumour recurrence.

Systematic review and meta-analysis of interferon after curative treatment of hepatocellular carcinoma in patients with viral hepatitis

BACKGROUND

A combined antiviral and tumoricidal effect of interferon (IFN) is assumed to occur after resection or ablation of hepatocellular carcinoma (HCC).

METHODS

An electronic search of the Medline, Embase and Central databases from January 1998 to October 2007 was conducted to identify randomized controlled trials evaluating adjuvant effects of IFN after curative treatment of HCC. A meta-analysis was performed to estimate the effects of IFN on 2-year outcome.

RESULTS

Seven trials enrolling a total of 620 patients were included in the meta-analysis. Adjuvant treatment with IFN significantly reduced the 2-year mortality rate after curative treatment of HCC, with a pooled risk ratio of 0.65 (95 per cent confidence interval 0.52 to 0.80); P < 0.001) in absence of any significant heterogeneity (I(2) = 0 per cent, P = 0.823 for chi(2)). The effect on reduction of tumour recurrence was less pronounced but still significant (pooled risk ratio 0.86 (95 per cent c.i. 0.76 to 0.97); P = 0.013). IFN had to be discontinued in 8-20 per cent of patients.

CONCLUSION

IFN has a significant beneficial effect after curative treatment of HCC in terms of both survival and tumour recurrence.

Successful outcome of severe adenovirus hepatitis of the allograft following liver transplantation

Here we report the first adult patient who survived severe adenoviral hepatitis of a liver graft, in contrast to 4 previously reported cases in adults, all of which had a fatal outcome. Early diagnosis was based on the immunohistological detection of adenoviral protein in the context of biopsy-proven hepatitis. Dramatic reduction of immunosuppression along with supportive care were the treatment strategies in this case. Adenoviral infection of the allograft should always be considered as a differential diagnosis when clinical signs of severe hepatitis are present after liver transplantation. Accurate diagnosis with immunohistochemical detection of viral proteins in the liver graft is of paramount importance for the early diagnosis and management of this uncommon, severe, and probably underdiagnosed entity.

How useful is PET/CT imaging in the management of post-transplant lymphoproliferative disease after liver transplantation?

Post-transplant lymphoproliferative disease (PTLD) is a serious and potentially life-threatening complication after solid organ transplantation. Here, we report our first experience with the use of PET/CT (positron emission tomography combined with computed tomogram) for the management of patients with PTLD after liver transplantation. Four patients with histologically proven PTLD were analyzed. Conventional work-up included physical examination and head-to-pelvis CT. PET/CT was used in one patient for initial staging and in all patients for follow-up. PET/CT positive findings underwent biopsy. Information provided by PET/CT resulted in a change of medical management in three of the four patients. Conventional work-up missed residual disease after surgery in one and failed to detect a tumor relapse in another patient. However, one patient disclosed a false positive PET/CT finding in the lungs. In conclusion, PET/CT may be a useful tool for staging and therapy monitoring of PTLD after liver transplantation.

[Surgical therapy of colorectal liver metastases]

The liver is the most common organ of distant colorectal metastases. Liver resection currently represents the best and only potentially curative treatment for metastatic colorectal cancer isolated to the liver. Five-year survival rates of 30 to 40% are reported after curative liver resection. Unfortunately, only 10 to 20% of patients with liver metastases without extraheaptic disease are amenable to surgical resection. Novel therapy strategies to improve respectability such as neoadjuvant chemotherapy, portal vein embolisation or ligature, resection combined with ablation and two-stage hepatectomy are currently evaluated. The overall goal of these treatments is to increase the proportion of patients with isolated colorectal liver metastases that can undergo curative resection. Despite curative resection, 60 to 70% of patients will develop recurrent disease. In case of isolated recurrence to the liver that is resectable, repeat liver resection is the treatment of choice. Adjuvant chemotherapy is directed to reduce the risk of recurrence after resection. Despite few encouraging randomised trials on adjuvant chemotherapy, there are no definitive recommendations for adjuvant chemotherapy.

Simplified microvascular suture techniques for rat liver transplantation as a microsurgical model with arterial blood supply

The methods for liver transplantation in the rat mainly used do not include reconstruction of the arterial blood supply to the liver. Furthermore, to ensure a short anhepatic phase these methods almost all entail specially developed cuff anastomoses in the recipient operation instead of the conventional microvascular suture technique. Thus an acceptable survival rate can be attained in the experimental animals. This detailed description of simplified microvascular suture techniques is intended to present an alternative to the cuff anastomoses used almost exclusively. In the donor operation with this method, the liver is dissected with an arterial pedicle including the abdominal segment of the aorta, and the liver is flushed in situ not only via the portal vein, but also via the hepatic artery. The organ is implanted in the recipient animal using simplified microvascular suture reconstruction of the arterial blood supply to the liver. Use of telescopic spectacles with 2-fold magnification has proven to be adequate for the entire procedure. With mastery of this method of rat liver transplantation, the average duration of the anhepatic phase is about 20 min, substantially below the 30-min limit which is critical for the survival of the experimental animals. The donor operation requires about 60 min, and the recipient operation 70 to 80 min. With this method, the spectrum of investigations on liver transplantation which are possible in the rat is substantially extended in that clinical conditions can be reproduced very much more exactly by combination of portal and arterial in-situ flushing in the donor operation and rearterialization of the transplant in the recipient operation, as compared to the transplanted rat liver being supplied only with portal venous blood.

Combined p53/Bax mutation results in extremely poor prognosis in gastric carcinoma with low microsatellite instability

Gastric cancer is highly refractory to DNA-damaging therapies. We therefore studied both gene mutation and protein expression of p53 and Bax in a cohort of 116 patients with gastric cancer who underwent R0-resection with a curative intent. Bax mutation was independent from severe microsatellite instability (MSI), that is, global mismatch repair deficiency as determined by analysis of BAT-25/BAT-26 microsatellite markers. Thus, Bax-frameshift mutation is a feature of tumors with low MSI. In contrast and as expected, no p53 mutations were observed in the microsatellite instable tumors. p53 Mutation or p53 overexpression did not have an impact on disease prognosis. p53-Inactivation was, however, associated with an extremely poor prognosis in the subgroup of patients with Bax-mutated tumors. Thus, we show for the first time that the combined mutation of p53 and Bax, two key regulators of the mitochondrial apoptosis pathway, results in an extremely aggressive tumor biology and poor clinical prognosis.

Functional interaction between fluorodeoxyuridine-induced cellular alterations and replication of a ribonucleotide reductase-negative herpes simplex virus

G207 is an oncolytic herpes simplex virus (HSV) which is attenuated by inactivation of viral ribonucleotide reductase (RR) and deletion of both gamma(1)34.5 genes. The cellular counterparts that can functionally substitute for viral RR and the carboxyl-terminal domain of ICP34.5 are cellular RR and the corresponding homologous domain of the growth arrest and DNA damage protein 34 (GADD34), respectively. Because the thymidylate synthetase (TS) inhibitor fluorodeoxyuridine (FUdR) can alter expression of cellular RR and GADD34, we examined the effect of FUdR on G207 bioactivity with the hypothesis that FUdR-induced cellular changes will alter viral proliferation and cytotoxicity. Replication of wild-type HSV-1 was impaired in the presence of 10 nM FUdR, whereas G207 demonstrated increased replication under the same conditions. Combined use of FUdR and G207 resulted in synergistic cytotoxicity. FUdR exposure caused elevation of RR activity at 10 and 100 nM, whereas GADD34 was induced only at 100 nM. The effect of enhanced viral replication by FUdR was suppressed by hydroxyurea, a known inhibitor of RR. These results demonstrate that the growth advantage of G207 in FUdR-treated cells is primarily based on an RR-dependent mechanism. Although our findings show that TS inhibition impairs viral replication, the FUdR-induced RR elevation may overcome this disadvantage, resulting in enhanced replication of G207. These data provide the cellular basis for the combined use of RR-negative HSV mutants and TS inhibitors in the treatment of cancer.

Effect of fibrin glue occlusion of the hepatobiliary tract on thioacetamide-induced liver failure

BACKGROUND

Expression and activation of hepatocyte growth factor (HGF) is stimulated by a complex system of interacting proteins, with thrombin playing an initial role in this process. The impact of temporary occlusion of the hepatobiliary tract with fibrin glue (major component thrombin) on the HGF system in acute and chronic liver damage in a rat model was investigated.

METHODS

Chronic liver damage was induced in 40 rats by daily intraperitoneal application of thioacetamide (100 mg/kg) for 14 days. After 7 days half of them received an injection of 0.2 mL fibrin glue into the hepatobiliary system. Daily intraperitoneal administration of thioacetamide continued for 7 consecutive days. The rats were then sacrificed for blood and tissue analysis. Acute liver failure was induced in 12 rats by intraperitoneal administration of a lethal dose of thioacetamide (500 mg/kg per day for 3 days) after an injection with 0.2 mL fibrin glue into their hepatobiliary tract. Survival rates and histological outcome were investigated and compared with control animals.

RESULTS

Fibrin glue occluded rats showed significantly lower liver enzyme activities and serum levels of bilirubin, creatinine and urea nitrogen. Immunohistochemistry revealed a significant increase in c-met-, HGFalpha- and especially HGFbeta-positive cells. Rats subjected to a lethal dose of thioacetamide survived when fibrin glue was applied 24 hours prior to the toxic challenge. These animals showed normal liver structure and no clinical abnormalities.

CONCLUSION

Fibrin glue occlusion of the hepatobiliary tract induces therapeutic and prophylactic effects on chronic and acute liver failure by stimulating the HGF system. Therefore, fibrin glue occlusion might be useful in treating toxic liver failure.

Analysis of p53/BAX/p16(ink4a/CDKN2) in esophageal squamous cell carcinoma: high BAX and p16(ink4a/CDKN2) identifies patients with good prognosis

PURPOSE

We have previously shown that loss of BAX expression is a negative prognostic factor in metastatic colorectal cancer. In the present study, we addressed the prognostic relevance of BAX and its upstream regulator p53 in squamous cell carcinoma (SCC) of the esophagus. Analysis of p16(ink4a/CDKN2) was included because p16(ink4a/CDKN2) and p53 were shown previously to cooperate during induction of cell cycle arrest and apoptosis.

PATIENTS AND METHODS

Retrospective analysis of 53 patients with curative intended R0 resection of esophageal SCC was done. Protein expression of BAX, p53, and p16(ink4a/CDKN2) was investigated by immunohistochemistry. In addition, tumor DNA was screened for BAX frameshift mutations by fragment length analysis and for p53 mutations by single-strand conformation polymorphism-polymerase chain reaction.

RESULTS

Overall median survival was 13.7 months. Patients with high BAX protein expression had a median survival of 19.5 months versus 8.0 months with low BAX expression (P <.005). High p16(ink4a/CDKN2) protein expression was associated with a median survival of 23.8 months versus 9.7 months with low p16(ink4a/CDKN2) (P =.011). The best survival (median, 45.8 months) was seen in a subgroup of 12 patients whose tumors bore the combination of both favorite phenotypes (ie, high BAX and high p16(ink4a/CDKN2) protein expression).

CONCLUSION

In this retrospective investigation, the combined analysis of BAX and p16(ink4a/CDKN2) shows subgroups in SCC of the esophagus with favorable (p16(ink4a/CDKN2)/BAX high expressing) or poor prognosis (loss of p16(ink4a/CDKN2)/loss of BAX). We suggest that such a multimarker analysis of apoptosis pathways could be useful for individualization of therapeutic strategies in the future, and suggest prospective studies to confirm these results.

Relevance of Ki-67 antigen expression and K-ras mutation in colorectal liver metastases

AIMS

The liver is a frequent site of metastases from colorectal cancer. While these lesions are potentially amenable to surgical resection, they are usually very aggressive, and recurrence is frequent. Mutations of the proto-oncogene K- ras are thought to impart a strong growth signal to tumour cells and are closely associated with the development of malignancies of the colon and rectum. Hepatic metastases from colorectal cancer have notably elevated proliferative rates. The present study was performed to investigate the relationship between proliferation or K- ras mutation and prognosis following curative resection of colorectal liver metastases.

METHODS

Colorectal liver metastases from 41 patients undergoing curative hepatic resection were examined for proliferation status and presence of K- ras mutations. The proliferative activity was assessed by Ki-67 immunohistochemistry. DNA from the same tissue samples was screened for point mutations in codon 12 of the K- ras gene using a novel microplate-based allelic-specific hybridization assay. Ki-67 scores and K- ras status were then related with patient survival as determined through retrospective analysis.

RESULTS

Median survival was 40 months. Patients with high Ki-67 scores (> or = 50%) had significantly shorter median survival compared with those with low scores (30 vs 44 months, log-rank P=0.02). A high Ki-67 score was an independent negative prognostic factor by multivariate regression analysis (relative risk=3.04, P=0.036). K- ras point mutations were detected in 6/41 patients (15%), but mutational status did not correlate with Ki-67 score or survival.

CONCLUSIONS

These findings suggest that the tumour proliferative index is a useful predictor of aggressive tumour behaviour and an indicator of patient survival. The presence of K- ras mutations does not appear to correlate with tumour proliferation status or patient survival.

Effects of preexisting immunity on the response to herpes simplex-based oncolytic viral therapy

Herpes simplex viruses (HSV) type 1 are the basis of a number of anticancer strategies that have proven efficacious in animal models. They are natural human pathogens and the majority of adults have anti-HSV immunity. The current study examined the effect of preexisting immunity on the response to herpes-based oncolytic viral treatment of hepatic metastatic cancer in a murine model designed to simulate a clinical approach likely to be utilized for nonneurological tumors. Specifically, the anticancer effects of NV1020 or G207, two multimutated HSV-1 oncolytic viruses, were tested in immunocompetent mice previously immunized with a wild-type herpes simplex type 1 virus. Mice were documented to have humoral as well as cell-mediated immunity to HSV-1. Tumor response to oncolytic therapy was not measurably abrogated by immunity to HSV at the doses tested. The influence of route of viral administration was also tested in models of regional hepatic arterial and intravenous therapy. Route of viral administration influenced efficacy, as virus delivered intravenously produced some detectable attenuation while hepatic arterial therapy remained unaffected. These results demonstrate that when given at appropriate doses and in reasonable proximity to tumor targets, HSV-based oncolytic therapy can still be expected to be effective treatment for patients with hepatic malignancies.

Use of phosphorous-31 nuclear magnetic resonance spectroscopy to determine safe timing of chemotherapy after hepatic resection

Liver resection induces accelerated growth of residual hepatic micrometastases. Adjuvant chemotherapy may improve outcome if administered early after resection but may prove lethal if initiated prior to completion of DNA synthesis in regenerating liver. This study investigates phosphorus-31 nuclear magnetic resonance ((31)P-NMR) as a noninvasive tool for measuring energy changes reflective of hepatic DNA synthesis and for predicting safe timing of chemotherapy after 70% hepatectomy. To evaluate metabolic changes in regenerating liver, quantitative three-dimensional (31)P-NMR was performed, using the technique of chemical shift imaging at various time points after 70% hepatectomy in adult male Fischer rats. Animals receiving a course of 2'-deoxy-5-fluorouridine (FUDR; 100 mg/kg, i.p. four times per day x 5), initiated at the time of operation, were also evaluated to observe the effects of chemotherapy on liver regeneration. Forty-eight hours after resection, hepatic nucleoside triphosphate (NTP), which reflects ATP content, fell 37% (P < 0.03) in animals undergoing hepatectomy alone. By contrast, animals receiving FUDR after hepatectomy demonstrated a mitigated NTP response, with a drop of only 17% (P = not significant), suggesting that interruption of DNA synthesis leads to a reduced consumption of ATP. Direct measures of DNA synthesis and nuclear proliferation were correlated with NMR findings. [(3)H]Thymidine incorporation and Ki67 immunohistochemistry were performed on liver samples from rats undergoing 70% hepatectomy with and without FUDR. Both [(3)H]thymidine incorporation and Ki67 expression were inhibited significantly at 48 h in animals receiving hepatectomy and FUDR, compared with those not treated with FUDR. To determine whether NMR changes could be used to identify safe timing of chemotherapy after hepatectomy, rats were treated with a 5-day course of FUDR initiated either prior to or after NMR changes normalized. Animals treated with FUDR at the point of NTP normalization (72 h) showed significantly improved survival over those that began treatment at operation (75 % versus 17 %; P = 0.0005, log rank test). FUDR inhibits hepatic DNA synthesis and influences mortality if administered too early after hepatectomy. Chemical shift imaging is a noninvasive tool that can identify metabolic changes coinciding with DNA synthesis and nuclear proliferation after hepatectomy. (31)P-NMR may be useful for determining safe timing of chemotherapy after liver resection.

Relevance of locoregional chemotherapy in patients with liver metastases from colorectal primaries

Progression of colorectal cancer can occur primarily isolated in the liver. But, only the minority of the affected patients is eligible for surgery. Initially, systemic chemotherapy was ineffective in the treatment of unresectable hepatic metastases. For this reason, intraarterial chemotherapy was introduced as treatment alternative to the systemic chemotherapy. Long-term intraarterial chemotherapy regimens with FUDR in patients with colorectal liver metastases, using implantable pumps and ports, resulted in improved response rates, which was confirmed by several randomized trials. However, an improvement in median survival has not yet been demonstrated after regional chemotherapy of hepatic metastases. Since the intraarterial therapy with floxuridine (FUDR) had been reported to result in a high rate of local toxicity, 5-fluorouracil (5-FU) was introduced into regional chemotherapy of the liver. A randomized trial demonstrated superiority of intraarterial 5-FU versus intraarterial FUDR therapy. Despite these reports about high response rates, the benefit of intraarterial chemotherapy remains questionable, because it has not yet resulted in a prolongation of median survival. For this reason, long-term regional chemotherapy cannot be considered as standard treatment and should therefore not be conducted outside controlled clinical trials. Further evaluations on this technique should only be performed in experienced centers.

[Technique and pathophysiology of isolated hypoxic perfusion of the abdomen]

Isolated hypoxic perfusion (IHP) is a commonly used technique in the treatment of abdominal malignancies. During a phase II-study the pathophysiology of this technique was explored in patients with advanced pancreatic cancer. Twenty perfusions of the abdomen were performed in 17 patients. Under general anesthesia, femoral vessels were dissected and two balloon catheters were inserted into aorta and vena cava cranial the celiac trunk and the hepatic veins. After instillation of 40 mg of Mitomycin C (MMC) into the running perfusion system, the perfusion was maintained for further 20 minutes. Blood samples were taken in 5-minute intervals to determine pH value, blood gases as well as concentrations of electrolytes, lactate and MMC in the arterial blood. Simultaneously, blood samples were taken from the perfusion blood via a side-port of the extracorporeal perfusion system. Additionally, perfusion pressures, arterial and central venous pressure, heart rate, and the pressure in the aorta distal the balloon catheter were registered continuously. All 20 perfusions had been undertaken without perioperative mortality. After inflating the balloon catheters, blood pressure and heart rate increased rapidly. Within 5 minutes of perfusion an increase in pCO2 and the concentrations of K+ and lactate in the perfusate were registered, while pH and pO2 decreased. Fifteen minutes after instillation of MMC, concentrations of MMC in arterial and perfusion blood were equal. Twenty-four hours after the perfusion all parameters had returned to normal values. IHP was well feasible in 20 consecutive perfusions without major technical problems. A distinct but tolerable combined acidosis resulted from IHP. Despite the exact positioning and control of the balloon catheters a complete isolation was not possible.

Relevance of neoadjuvant and adjuvant treatment for patients with resectable liver metastases of colorectal carcinoma

BACKGROUND

Excellent results after resection of colorectal liver metastases are associated with a high rate of recurrence. Influenced by positive results of palliative and adjuvant treatment in advanced cancer, various chemotherapy regimens were evaluated to improve long-term results.

METHODS

The databases Medline and Cancerlit (1982-1998) gave information about 675 patients who were treated either by means of systemic, intra-arterial, intraportal or intraperitoneal administration before or after liver resection.

RESULTS

In general, the feasibility of an adjuvant treatment was tested. Proof has been furnished for the practicability of systemic and arterial therapy and for immunotherapy after liver resection whereas, for peritoneal and portal treatment, further studies are necessary. In a few non-randomised trials, it has been possible to discern a trend towards an improvement due to adjuvant postoperative therapy using historical or matched-pair control groups. Until now, only one of five randomised studies has been published. Six months of postoperative adjuvant intra-arterial treatment using 5-fluorouracil (1000 mg/m(2) for 5 days every 28 days) and folinic acid (200 mg/m(2) for 5 days every 28 days) was compared with observation only. Neither in the intention-to-treat nor in the as-treated analysis was median survival time (34.5 months versus 40. 8 months and 39.7 months versus 44.8 months, respectively) significantly increased. As neoadjuvant treatment was successful in primary non-resectable patients, this approach is now being tested in resectable patients.

CONCLUSION

Despite several theoretical reasons for post- or preoperative treatment in resectable patients, every approach should be tested using of controlled studies.

Endothelin-induced contraction of the portal vein in cirrhosis

Endothelin (ET) is one of the most potent vasoconstrictors known so far. It has been proposed that the ET-induced contraction of hepatic stellate cells (Ito, endothelial cells) is an important mechanism for the development of portal hypertension. The purpose of this study was to investigate in an in vitro model whether ET causes a contraction of the portal vein which can contribute to portal hypertension in cirrhosis. Portal veins from normal and cirrhotic rats were used for experiments. Measurements were performed in vitro for cumulative concentrations of ET-1 and ET-3 (1, 5, 10, 50 and 100 nM). Both ETs caused a dose-dependent increase in portal venous tension; the maximal tension (Tmax) was measured at 50 nM. The measured Tmax was higher for cirrhotic (ET-1: Tmax = 189%; ET-3: Tmax = 175%) than for normal rats (ET-1: Tmax = 130%; ET-3: Tmax = 151%). ET-3 produced a higher tension of portal veins in normal rats than ET-1. In conclusion, this study shows that portal veins from cirrhotic rats react more sensitively to ET than those from normal rats. Besides the ET-induced contraction of hepatic stellate cells, contraction of the portal vein and its intrahepatic branches, especially in cirrhotic individuals, has to be considered as a further mechanism of ET contributing to portal hypertension.

Analysis of the p53/BAX pathway in colorectal cancer: low BAX is a negative prognostic factor in patients with resected liver metastases

PURPOSE

To determine the prognostic value of the central downstream apoptosis effector BAX in relation to its upstream regulator p53 in R0-resected hepatic metastases of colorectal cancer.

PATIENTS AND METHODS

Retrospective analysis of 41 patients who underwent potentially curative resection of liver metastases from colarectal cancer was performed. Tumor DNA was screened for p53 mutations by single-stranded conformational polymorphism polymerase chain reaction and for BAX frameshift mutations by fragment length analysis. Protein expression of BAX, p21, and p53 was investigated by immunohistochemistry.

RESULTS

Overall median survival was 40.2 months. Tumors with BAX frameshift mutations were considered microsatellite mutator phenotype-positive and were excluded from further prognostic analyses. Patients with high BAX protein expression had a median survival of 53.6 months compared with 35.4 months for patients with low BAX expression (P < .05). The negative prognostic value of low BAX expression was more evident in those patients with wild-type p53 (median survival, 54.0 v 23.3 months for BAX-negative tumors; P < .01). Low BAX expression was an independent negative prognostic marker in multivariate regression analysis for all patients independent of the p53 status (relative risk, 3.03, P = .03), especially for p53 wild-type tumors (relative risk, 8.21; P = .0095).

CONCLUSION

We conclude that low BAX expression is an independent negative prognostic marker in patients with hepatic metastases of colorectal cancer. The best survival was seen in patients with an intact p53-to-BAX pathway; ie, wild-type p53- and BAX-positive tumors. Thus, analysis of apoptosis signaling pathways (here, p53 in concert with its downstream death effector, BAX) might yield more prognostic power in future studies as compared with analysis of single genes such as p53 alone.

[Isolated hypoxic perfusion with mitomycin C confers no benefit for patients with advanced pancreatic carcinoma]

Since therapy options in the treatment of advanced pancreatic cancer are rare, the present study has investigated whether patients with advanced pancreatic cancer may profit from isolated hypoxic perfusion (IHP) of the abdomen with mitomycin C. None of the 17 treated patients responded to IHP with mitomycin C, and the survival time corresponded to that of untreated patients. On the basis of these results, this procedure should no longer be used as treatment for patients with advanced pancreatic cancer.

[The status of regional long-term chemotherapy in liver metastasis]

In numerous tumors, metastasis can be limited to the liver. In non-resectable patients, regional treatment modalities, especially arterial cytostatic infusion, are favored in contrast to systemic chemotherapy, whereas intraportal or intraperitoneal application is not successful. Improved results with high response rates have been reported after development of intra-arterial (i.a.) long-term regimens with FUdR in patients with colorectal liver metastases using implantable pumps and ports. However, a survival benefit could only be demonstrated in comparison with a control group only treated symptomatically. Because of several reports on major local toxicity of i.a. FUdR treatment (i.e. chemical hepatitis and biliary sclerosis) several other effective i.a. 5-FU regimens have been developed. A randomized study has demonstrated superiority of i.a. 5-FU versus i.a. FUdR. In comparison with systemic treatment, superiority has only been demonstrated in patients with an intrahepatic tumor burden of < 25%. Publications about regional treatment of patients with breast, gastric cancer or carcinoid liver metastases are rare. Despite the high response rates reported, the benefit of arterial chemotherapy remains questionable. Overall, local long-term chemotherapy cannot be recommended outside of studies as a primary treatment. However, extensive experience and new drugs support the idea of conducting further regional studies.

Isolated hypoxic perfusion with mitomycin C in patients with advanced pancreatic cancer

AIMS

Chemotherapy as a palliative therapy option for patients with advanced pancreatic cancer remains disappointing. Some authors have recently claimed high response rates and a prolongation of median survival after regional chemotherapy. Isolated perfusion may result in the highest drug concentrations within the target tissue without causing systemic side-effects. An established, commercially available system of isolated hypoxic perfusion (IHP) was therefore evaluated in patients with unresectable or recurrent pancreatic cancer.

PATIENTS AND METHODS

IHP was performed in 17 patients with unresectable pancreatic cancer. Five women and 12 men with a median age of 61 years were treated. A 20-min isolated hypoxic perfusion was performed after 40 mg of mitomycin C (MMC) had been instilled into the running perfusion system over 5 min. Tumour response was evaluated by CT-scan 6 weeks after IHP.

RESULTS

Twenty perfusions were carried out in 17 patients. Within 10 min of perfusion, the perfusate's PO2 decreased to 13% of the baseline value. Five minutes after the infusion of MMC a local concentration of 15.2 mg/litre was observed. Toxicity-related deaths did not occur. Nausea and vomiting (NCI> or =II: 12 episodes) were the most frequently observed toxicities after IHP. In five patients (29%) a deep vein thrombosis occurred. None of the treated patients responded to the regimen used in this trial. The median survival time after IHP was 4.2 months (range 1.3-21).

CONCLUSIONS

The overall rate of side-effects and complications after IHP was high. In spite of some hopeful reports on this treatment in recent years, IHP did not show any benefit in terms of tumour response or median survival. On the basis of these experiences, this procedure should no longer be used as treatment for patients with unresectable or recurrent pancreatic cancer.

A pilot study on intensive weekly 24-hour intra-arterial infusion with 5-fluorouracil and folinic acid for colorectal liver metastases

PURPOSE

A pilot study was performed to evaluate the tolerance and efficacy of a hepatic arterial infusion (HAI) of 5-fluorouracil (5-FU) and folinic acid (FA) in patients with unresectable liver metastases from colorectal carcinoma.

PATIENTS AND METHODS

In 11 patients, 135 applications of high-dose HAI of 5-FU/FA were administered. All patients had been intra-arterially pretreated, and 2 of them had received an additional intravenous therapy. The chemotherapy regimen consisted of a weekly HAI of FA 500 mg/m2 over 1 h, immediately followed by HAI of 5-FU over 24 h. Four patients received a 5-FU starting dose of 2,000 mg/m2 and 7 patients of 2,400 mg/m2. One course consisted of 12 weekly applications interrupted by 1 week after 6 applications and 4 weeks after 12 applications.

RESULTS

The applied regimen caused only mild side effects. Nausea and vomiting were the most frequently side effects with 36 episodes out of 135 applications (WHO grade > or = 3: 2 episodes). Diarrhea was a minor problem occurring with 8 episodes (WHO grade > or = 3: 1 episode). There was no evidence of myelosuppression, hand-foot syndrome, neurotoxicity, and biliary sclerosis. A partial remission was observed in 3 patients, and a disease stabilization in 2 patients while the disease progressed in 6 patients under high-dose HAI of 5-FU/FA.

CONCLUSION

The present pilot study demonstrates that the weekly high-dose HAI of 5-FU/FA is well tolerated and associated with very mild toxicity. Because of the encouraging response rate in patients, whose disease progressed under the conventional intra-arterial therapy either with 5-FU/FA or 5-fluorodeoxyuridine, this regimen seems to be an effective second-line treatment and should be evaluated in nonpretreated patients in a phase II study.

[Liver transplantation and splenectomy in idiopathic portal hypertension]

Idiopathic portal hypertension (IPH) was diagnosed in a 30-year-old man. Clinical signs were splenomegaly, leucothrombocytopenia, and esophageal varices of fourth degree. The histology of the liver biopsy showed portal fibrosis with no evidence of cirrhosis. No causing agent or known disease could be found for the histopathological and clinical features. Due to a severe deterioration of general condition and a decline of synthetic liver function, liver transplantation and splenectomy were performed. The histological examination of the explanted liver revealed features of IPH, demonstrating portal fibrosis and dilated vessels adjacent to portal tracts; no cirrhosis was found. The postoperative recovery was without any severe complications. The duration of hospitalization was 28 days. Following liver transplantation, the esophageal varices disappeared and leucocytes, platelets as well as parameters of hepatic synthesis reached normal values. Initially, the immunosuppression was composed of prednisolon, tacrolimus, and antibodies against IL-2 receptors (BT 563) and was later continued with prednisolon and tacrolimus. Within the follow-up observation of 26 months, there was no evidence for graft rejection, severe infection, or occurrence of portal hypertension. Up till now the patient is in good condition with normal graft function. Liver transplantation may be a curative therapy for patients with advanced disease of IPH but the long-term follow-up after transplantation has to show whether IPH can reoccur.

An improved model for rat liver transplantation including arterial reconstruction and simplified microvascular suture techniques

For experimental liver transplantation in the rat, the models that have been used most frequently do not include reconstruction of the arterial blood supply to the liver. In these procedures, specially developed cuff anastomoses rather than the conventional microvascular suture technique are used almost exclusively in the recipient operation, so that the anhepatic time is minimized. In this study the technical details of an improved rat model for orthotopic liver transplantation are described. During the donor operation in this experimental method, the liver is prepared with an arterial pedicle that includes the abdominal segment of the aorta, permitting perfusion in situ of the portal vein as well as the hepatic artery. The transplantation of the excised donor organ into the recipient site is carried out with simplified microvascular suture techniques and includes reconstruction of the arterial supply to the liver. Anastomosis of the bile duct is accomplished by choledocho-choledochostomy with a splint technique and supplemental suturing. For the entire procedure, magnifying glasses with 2- to 2.5-fold magnification are sufficient. When this technique has been mastered, the average duration of the anhepatic phase is about 20 min, well below the critical 30-min limit for survival of the experimental animals. As proficiency increased, the perioperative mortality was reduced to 9.2% (n = 130). With the combination of portal and arterial in situ flushing during the donor operation and the rearterialization of the transplant during the recipient operation, the clinical conditions can be approximated more closely than is possible when the transplanted rat liver is supplied only by the portal vein. Use of microvascular suture techniques, without cuff anastomoses, reduces the need for ex situ handling of the donor organ.