Transcatheter arterial chemoembolization as primary treatment for hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) in Western populations has historically been associated with poor survival.

METHODS

In this study, we conducted a 7-year retrospective analysis of patients with HCC undergoing transcatheter arterial chemoembolization (TACE) at our institution and examined demographics, outcomes, and complications.

RESULTS

During the period of study, 39 patients (25 male [64%], mean age 58 [range 17 to 86]) underwent a total of 78 chemoembolization treatments. During the same time period, an additional 31 patients received supportive care only. The majority of patients had late stage disease (American Joint Committee on Cancer stage III, IVa, or IVb) with no statistical difference noted between the two groups (P = 0.2). However, patients receiving supportive care only had significantly worse hepatic dysfunction by Child's classification (P = 0.005). Twenty-nine patients (74%) had documented cirrhosis, with hepatitis C being the most common cause in 11 of 29 (38%). In patients undergoing TACE, overall actuarial survival was 35%, 20%, and 11% at 1, 2, and 3 years with a median survival of 9.2 months, significantly improved over the group receiving supportive care only (P < 0.0001). Median survival for the group receiving supportive care was less than 3 months. Neither age nor stage had a significant impact on survival. The most common complications of TACE included transient nausea, abdominal pain, vomiting, and fever.

CONCLUSIONS

TACE is a safe and effective therapeutic option for selected patients with HCC not amenable to surgical intervention.

Comparison of arcuate-legged clipped versus sutured hepatic artery, portal vein, and bile duct anastomoses

Attempts at improving anastomoses have included the development of stapling techniques. Our purpose was to evaluate arcuate-legged clipped versus standard sutured anastomoses of the hepatic artery (HA), portal vein (PV), and bile duct in a porcine liver transplantation model. Two groups of pigs were studied intraoperatively and 1 day after liver transplantation. A control group underwent sutured anastomosis of PV and HA with polypropylene and of bile duct with polydioxanone (n = 8). An experimental group underwent anastomoses with arcuate-legged clips (n = 8). We analyzed the time to perform anastomosis and flows before and at various time points after anastomosis. In addition, patency and histology of the anastomoses were evaluated 1 day after operation, including a fibrin-thrombosis score, medial injury, and inflammation score. Times to complete HA and PV anastomoses were not different between clipped and sutured groups. However, the time was shorter to complete bile duct anastomosis with clips than with sutures (6.3 +/- 1.1 minutes and 13.3 +/- 2.0 minutes, respectively). Flows through HA anastomoses were not different between groups, but flow through the PV was higher in clipped compared with sutured anastomosis (P = 0.06). Patency was 100 per cent with no leaks for all three anastomoses in both groups. Histologic data were similar between vascular anastomotic groups. Sutured bile duct anastomoses revealed mild smooth muscle injury in 75 per cent whereas clipped bile duct anastomoses displayed no smooth muscle injury. We conclude that arcuate-legged clipped anastomosis represents a viable option to sutured anastomoses of the PV, HA, and bile duct anastomoses. Bile duct anastomoses were completed in less than half the time and with less tissue damage documented histologically.

Nitric oxide and thromboxane A2-mediated pulmonary microvascular dysfunction

OBJECTIVES

To examine whether the lung releases nitric oxide (NO) in response to thromboxane A2 and to examine the local release of NO as a protective compensatory mechanism by which the lung responds to the proinflammatory and vasoactive effects of thromboxane A2.

DESIGN

The lungs of anesthetized Sprague-Dawley rats were perfused in vitro with Krebs-Henseleit buffer that contained an inhibitor of NO synthase (nitroglycerinenitro-L-arginine methyl ester [L-NAME]) (10(-4) mol/L), an NO donor (sodium nitroprusside) (10(-8) mol/L), or perfusate alone. Following equilibration, the thromboxane A2 receptor agonist 9,11-dideoxy-11alpha, 9alpha-epoxymethanoprostaglandin F2alpha(U-46619) (7.1 X 10(-8) mol/L) was added to the perfusate. Fifteen minutes later, the capillary filtration coefficient, pulmonary arterial pressure, and vascular resistance were measured. Pulmonary NO release was assessed by quantitating the release of cyclic guanosine monophosphate into the perfusate.

RESULTS

The capillary filtration coefficient of lungs exposed to U-46619 was 3.5 times greater than that of lungs perfused with buffer alone (P<.05). The addition of sodium nitroprusside reduced the increase in capillary filtration coefficient associated with U-46619 by 50% (P<.05) whereas L-NAME had no effect. The addition of U-46619 to the perfused lung caused a 3.0+/-0.4 mm Hg increase in pulmonary artery pressure (P<.01) with a corresponding rise in total vascular resistance (P<.05). This effect was exacerbated by L-NAME (P<.05) and inhibited by sodium nitroprusside (P<.05). Exposure of the isolated lungs to U-46619 caused a 4-fold increase in cyclic guanosine monophosphate levels within the perfusate.

CONCLUSION

These data are consistent with the hypothesis that NO release may be an important protective mechanism by which the lung responds to thromboxane A2.

The effect of nutritional and hormonal supplementation on protein synthesis immediately after liver transplantation

We have previously shown that immediately after liver transplantation (LT) the porcine recipient exhibits elevated plasma glucagon, increased fractional synthetic rate (FSR) of fibrinogen, and decreased FSR of fixed or structural liver proteins. The purpose of this study was to evaluate the effect of nutritional and hormonal supplementation on these observations 24 h after LT. Two groups of nine pigs were studied 1 day after LT using radioisotopic and arteriovenous difference techniques. A control group underwent LT with saline infusion and a supplemented group underwent LT with infusion of glucose, amino acids (6 and 1.06 mg/kg. min, respectively), and intraportal insulin (0.6 mU/kg. min) and glucagon (1.3 ng/kg. min). Primed constant infusions of [3H]leucine were used to determine leucine flux, an estimate of whole body protein breakdown, and fractional synthetic rates (FSR). The following changes were noted with supplementation: elevated plasma insulin (6 +/- 1 versus 29 +/- 4 microU/ml, control versus supplemented, respectively, P < 0.05), decreased glucagon to normal levels (323 +/- 65 versus 102 +/- 12 pg/ml, P < 0.05), decreased fibrinogen FSR (108 +/- 15 versus 70 +/- 6%/day, P < 0.025), and increased fixed liver protein FSR (8 +/- 1 versus 13 +/- 2%/day, P < 0.05, respectively). Albumin FSR was unaltered by supplementation (8 +/- 2 versus 6 +/- 1%/day, respectively). Nutritional and hormonal supplementation immediately after LT restored the measured protein synthesis in the allograft to near normal levels 1 day after transplantation.

Hepatocellular carcinoma outcomes based on indicated treatment strategy

Hepatocellular carcinoma (HCC) in Western populations historically has been associated with poor survival. In this study, we conducted a 7-year retrospective analysis of patients evaluated at our institution with HCC to determine the effects of newer treatment strategies on outcome. During the period of study, 117 patients [86 (74%) male; mean age, 59 years (range, 16-85)] were evaluated with treatment as follows: surgical resection in 22 (19%), chemoembolization with or without systemic chemotherapy in 40 (35%), systemic treatment alone in 16 (13%), orthotopic liver transplantation in 8 (7%), and supportive care only in 31 (26%). Sixty-nine patients (59%) had documented cirrhosis, with hepatitis C being the most common cause in 27 of 69 (39%). In patients receiving no treatment, median survival was just under 3 months, with only two 1-year survivors. Patients with orthotopic liver transplantation had 1-, 2-, and 3-year survival rates of 87, 87, and 58 per cent compared with 69, 52, and 43 per cent in surgically resected patients. Survival after chemoembolization was 35, 20, and 11 per cent at 1, 2, and 3 years, whereas survival after systemic chemotherapy was 30 and 15 per cent at 1 and 2 years, respectively. One-year survival was improved in noncirrhotic patients compared with cirrhotics (47% vs 29%; P < 0.05) but was no different in patients younger than 55 years compared with older patients (38% vs 38%). When possible, surgical treatment strategies offer superior survival.

Vanderbilt experience with cryosurgery for 25 advanced hepatic tumors

There are reports that suggest cryosurgical techniques may be a useful adjunct or even a viable alternative to surgical resection for hepatobiliary malignancies. Our objective was to evaluate the clinical results following cryoablation in conjunction with surgical resection for advanced hepatic tumors. Cryosurgical techniques were used in 25 consecutive patients with advanced liver tumors (1) to achieve a > 1-cm tumor-free margin when standard surgical margins were close, (2) to manage multiple tumor nodules with or without standard surgical resection, or (3) to increase chemotherapy response rates in conjunction with hepatic arterial portocath placement. In these 25 patients cryoablation was applied to 44 of 91 lesions--independently in four patients and in combination with hepatic resection in 21 patients. Cryoablation was used in seven patients because of close surgical margins. In 18 patients cryosurgery was used for complete lesion ablation. In 14 of the 18 patients cryosurgery and resection were used for different lesions; in four cryosurgery alone was used. Transient changes in hepatic enzymes, PT, PTT, and platelets were at maximum on postoperative days 1 to 3. Surgical mortality and morbidity rates were 4% and 68% respectively. Coagulation abnormalities were common; at least 30% reduction in platelets occurred in all patients and a > 50% reduction occurred in 15 of 25 (60%). Sixteen patients had a PT > 15 sec and five of these 16 also had platelet count < 50,000. Associated complications included one wound hematoma, one GI hemorrhage, one intracranial hemorrhage, and one hepatic hemorrhage from the cryosurgical site. 96%, 66%, 49%, 35%, and 20% of patients were surviving respectively at 6, 12, 18, 24, and 36 months. This report helps define the risks and results of cryosurgical ablation in conjunction with surgical resection for very advanced hepatobiliary tumors. Management of lesions contiguous to major blood vessels can include the Pringle maneuver or total hepatic vascular isolation. Cryoablation can be applied carefully as a complement to resection to achieve total tumor ablation in selected otherwise unresectable patients.

Management of bronchobiliary fistula as a late complication of hepatic resection

Bronchobiliary fistula is an uncommon but remarkable complication after hepatic resection. The case reported illustrates the clinical presentation and preferred initial management of these fistulae. A 61-year-old white male underwent two wedge resections for colorectal metastases to the liver with removal of a portion of the right diaphragm. Four years later, he developed obstructive jaundice secondary to tumor recurrence in the porta hepatis, which required endoscopic stent placement, radiation, and chemotherapy. Almost 2 years later, he developed frank biliptysis. Percutaneous transhepatic cholangiography (PTC) revealed occlusion of the common hepatic duct stent and a bronchobiliary fistula. With adequate reestablishment of common duct drainage, the patient rapidly improved and was discharged free of symptoms. Bronchobiliary fistulae are rare complications of hepatic resection that can present from days to years after operation. Endoscopic retrograde cholangiopancreatography and PTC are the diagnostic studies of choice and offer the possibility of therapeutic intervention. Although large series in the literature emphasize the surgical management of bronchobiliary fistulae, the reoperative procedures tend to be complicated, with a significant morbidity and mortality. Nonsurgical interventions via endoscopic retrograde cholangiopancreatography or PTC are more recently notably successful when resolution of a distal biliary obstruction is accomplished. Only after aggressive attempts at nonoperative, interventional techniques have failed should operative approaches be entertained.

Intestinal reperfusion-induced pulmonary edema is related to increased pulmonary inducible nitric oxide synthase activity

BACKGROUND

This study examines the hypothesis that specific inhibition of the inducible isoform of nitric oxide synthase (iNOS) will attenuate intestinal reperfusion-induced pulmonary microvascular dysfunction.

METHODS

Sprague-Dawley rats underwent intestinal ischemia-reperfusion (IR) or sham operation (SHAM). Before injury, the animals received a selective inhibitor of iNOS (S-methylisothiourea sulfate, SMT: L-N6-[1-iminoethyl] lysine L-NIL), a nonselective inhibitor of NOS (NG-nitro-L-arginine methylester, L-NAME) or vehicle (0.9% saline). IR-induced changes in pulmonary microvascular permeability were assessed by quantitating the extravasation of Evans blue dye (EBD)-bound protein into the lung. Pulmonary iNOS activity and content were assessed by radiochemical analysis and Western blot, respectively.

RESULTS

There was 60% more EBD within the lungs of animals sustaining IR when compared with controls (P < .05). Pretreatment with SMT or L-NIL totally prevented the increase in EBD extravasation associated with IR. In contrast, pretreatment with L-NAME resulted in a 10% increase in dye extravasation in those animals sustaining IR when compared with similarly injured animals receiving saline (P > .05). There was significantly greater iNOS activity and enzyme content within the lungs of animals sustaining IR compared with controls.

CONCLUSIONS

These data are consistent with the hypothesis that the release of nanomolar quantities of nitric oxide generated by iNOS contributes to IR-induced pulmonary microvascular dysfunction.

Impact of Sandimmune, Neoral, and Prograf on rejection incidence and renal function in primary liver transplant recipients

Following primary liver transplantation, immunosuppressive efficacy of Neoral and Prograf was similar and superior to that of Sandimmune. Rejection incidence was statistically increased with Sandimmune therapy. Incidence of hypertension, posttransplant diabetes mellitus, and infectious complications was not statistically different. Although early compromise in renal function was associated with Sandimmune, Neoral, and Prograf immunosuppression, no progressive renal dysfunction was identified.

Experience with neoral versus sandimmune in primary liver transplant recipients

We compared results using Neoral versus Sandimmune, each in combination with steroid and azathioprine immunosuppression, in primary liver transplantation recipients. There were 15 patients in each group with similar demographic distributions. Intravenous cyclosporine was stopped at 4.3 +/- 1.9 days in the Neoral group vs 7.8 +/- 4.9 days in the Sandimmune group. (P < 0.025). Cyclosporine levels in the first 10 days were higher (mean 306 ng/ml vs 231 ng/ml) in the Neoral group than the Sandimmune group (P < 0.05). The Neoral dose was less than the Sandimmune dose (mean 5.5 ng/kg per day vs 7.9 ng/kg per day) to achieve these levels in that time period (P < 0.05). Two patients (13%) experienced three episodes of biopsy-proven rejection in the Neoral group compared to nine patients (60%) with 12 episodes of rejection in the Sandimmune group (P < 0.025). Incidences of neurological and renal complications were similar between the groups. Infections requiring treatment were also similar. Liver function, renal function, and marrow function, evaluated at days 7, 14, 21, 28, and 2, 4, 6, and 12 months post-transplant, were not different between the groups. In summary, shorter use of intravenous cyclosporine and quicker stabilization of trough cyclosporine levels was achieved with Neoral than with Sandimmune. In the early post-transplant period, higher levels with lower doses were achieved with Neoral than with Sandimmune. In our experience, the incidence of rejection was lower with Neoral than with Sandimmune. There were similar lengths of hospitalization, mortality, adverse events, retransplantation, and similar liver, renal, and marrow function up to 1 year post-transplantation. Because of this experience, we continued to use Neoral in a total of 59 primary liver transplant recipients. We have not used intravenous cyclosporine in the last 44 patients. Follow-up was a mean of 11.4 months, ranging from 1 to 27 months. The incidence of rejection was 24% in these 59 patients compared to our historical experience of 70% using Sandimmune.

Renal function in primary liver transplant recipients receiving neoral (cyclosporine) versus prograf (tacrolimus)

Immunosuppressive efficacy of Neoral and Prograf following primary hepatic transplantation was comparable. Incidence of rejection episodes, infectious complications, hypertension, and postoperative diabetes mellitus was comparable. Although clinical use of both immunosuppressants was associated with early compromise in renal function, no progressive renal dysfunction was observed.

Hepatic artery chemoembolization for management of patients with advanced metastatic carcinoid tumors

BACKGROUND

Patients with advanced metastatic carcinoid tumors who have disease progression despite conventional therapy are left with few therapeutic options. Hepatic artery chemoembolization (HACE) may play a role in palliating these patients' symptoms.

METHODS

Fifteen patients with biopsy-proven advanced bilobar hepatic carcinoid metastases who demonstrated progression of symptoms and/or tumor size despite treatment with somatostatin analogues were treated with intra-arterial chemotherapy and HACE to determine efficacy and safety. Five days of intra-arterial 5-fluorouracil (1 g/m2) were followed by HACE with adriamycin (60 mg), cisplatin (100 mg), mitomycin C (30 mg), and polyvinyl alcohol (Ivalon); 200 micron to 710 micron). Patients were continued on octreotide at the same dose (150 to 2000 microg subcutaneous q 8 hours) before, during, and after the procedure.

RESULTS

Efficacy of treatment was assessed by comparing pretreatment and 3-month clinical, laboratory, radiographic, and quality of life parameters. Symptoms were improved in 8 of 12 patients who had diarrhea, 7 of 12 who had flushing, 9 of 12 who had abdominal pain, and in 4 of 7 who had malaise. Elevated tumor markers decreased in all patients. Biochemical markers (mean +/- SE) at 3 months decreased by 60% +/- 6% for 5-HIAA, 75% +/- 10% for chromogranin A and 50% +/- 7% for neuron-specific enolase. Tomographic assessment revealed tumor liquefaction in 10 of 13 patients. The Karnofsky performance status improved from a mean of 66 +/- 2 to 84 +/- 2 (P <0.001). Median follow-up was 16 months, with 13 deaths occurring from 1 week to 71 months after treatment.

CONCLUSIONS

Hepatic artery chemoembolization improves symptoms of carcinoid syndrome, has a high tumor response rate, and improves short-term quality of life in this group of patients with advanced hepatic carcinoid disease.

Evaluation of benign vs malignant hepatic lesions with positron emission tomography

BACKGROUND

In most malignant cells, the relatively low level of glucose-6-phosphatase leads to accumulation and trapping of [18F]fluorodeoxyglucose (FDG) intracellularly, allowing the visualization of increased uptake compared with normal cells.

OBJECTIVES

To assess the value of FDG positron emission tomography (PET) to differentiate benign from malignant hepatic lesions and to determine in which types of hepatic tumors PET can help evaluate stage, monitor response to therapy, and detect recurrence.

DESIGN

Prospective blinded-comparison clinical cohort study.

SETTING

Tertiary care university hospital and clinic.

PATIENTS

One hundred ten consecutive referred patients with hepatic lesions 1 cm or larger on screening computed tomographic (CT) images who were seen for evaluation and potential resection underwent PET imaging. There were 60 men and 50 women with a mean (+/-SD) age of 59 +/- 14 years. Follow-up was 100%.

INTERVENTIONS

A PET scan using static imaging was performed on all patients. The PET scan imaging and biopsy, surgery, or both were performed, providing pathological samples within 2 months of PET imaging. All PET images were correlated with CT scan to localize the lesion. However, PET investigators were unaware of any previous interpretation of the CT scan.

MAIN OUTCOME MEASURES

Visual interpretation, lesion-to-normal liver background (L/B) ratio of radioactivity, and standard uptake value (SUV) were correlated with pathological diagnosis.

RESULTS

All (100%) liver metastases from adenocarcinoma and sarcoma primaries in 66 patients and all cholangiocarcinomas in 8 patients had increased uptake values, L/B ratios greater than 2, and an SUV greater than 3.5. Hepatocellular carcinoma had increased FDG uptake in 16 of 23 patients and poor uptake in 7 patients. All benign hepatic lesions (n = 23), including adenoma and fibronodular hyperplasia, had poor uptake, an L/B ratio of less than 2, and an SUV less than 3.5, except for 1 of 3 abscesses that had definite uptake.

CONCLUSIONS

The PET technique using FDG static imaging was useful to differentiate malignant from benign lesions in the liver. Limitations include false-positive results in a minority of abscesses and false-negative results in a minority of hepatocellular carcinoma. The PET technique was useful in tumor staging and detection of recurrence, as well as monitoring response to therapy for all adenocarcinomas and sarcomas and most hepatocellular carcinomas. Therefore, pretherapy PET imaging is recommended to help assess new hepatic lesions.

Outcomes analysis in 100 liver transplantation patients

BACKGROUND

There is an increasing demand for outcomes analysis, including quality of life and financial analysis, following medical interventions and surgical procedures. We analyzed outcomes for 100 consecutive patients undergoing liver transplantation during a period of case management revision.

METHODS

Patient survival was calculated by Kaplan-Meier actuarial methods. The Karnofsky performance status was objectively assessed for surviving patients up to 6 years after transplantation and was evaluated by repeated measures analysis of variance and covariance. Subjective evaluation of quality of life over time was obtained using the Psychosocial Adjustment to Illness Scale. The correlations between time and scale were calculated. Financial data were accumulated from billing records.

RESULTS

Six-month, 1-year, 2-year, and 3- through 5-year survival was 86%, 84%, 83%, and 78%, respectively. Karnofsky performance status confirmed poor functional status preoperatively with a mean of 53 +/- 2, but significantly improving to 72 +/- 2 at 3 months, 80 +/- 2 at 6 months, 90 +/- 1 at 1 year, 92 +/- 1 at 2 years, 94 +/- 1 at 3 years, 96 +/- 1 at 4 years, and 97 +/- 1 at 5 years (P <0.001). Psychosocial Adjustment to Illness Scale scores demonstrated significant improvement following transplantation overall (r = -0.33), improving most in sexual relationships (r = -0.41), and domestic environment (r = -0.35; P <0.001). Median length of stay for the first half of the patients was 19 days declining to 11 days for the second half. Median hospital charges declined from $105,000 to $90,000.

CONCLUSIONS

Quality of life parameters assessed both by care givers (Karnofsky) and by patients (Psychosocial Adjustment to Illness Scale) improved dramatically following transplantation and over time, demonstrating that liver transplantation effectively restores a good quality of life. Outcomes can be improved while reducing length of stay and charges through modifications in case management.

Net hepatic glucose output is normal on postoperative day 1 after liver transplantation

The liver plays a central role in carbohydrate metabolism and glucose homeostasis; therefore, the rapid recovery of glucose homeostasis after liver transplantation (LT) is important. The purpose of this study was to evaluate hepatic and whole-body glucose production (WBGP) on postoperative day 1 after LT using a combination of arteriovenous differences and radioisotope techniques. Two groups of female commercially bred pigs with an average body weight of 31.9 +/- 1.4 kg were studied. A control group (n = 6) underwent laparotomy. A transplanted group (n = 6) was submitted to LT. All pigs were instrumented with catheters placed in the carotid artery and the hepatic, portal, and jugular vein, and flow probes were placed around the hepatic artery and portal vein. WBGP was measured by a primed constant infusion of 3-[3H]glucose 1 day postoperatively. Plasma glucose was 89 +/- 6 versus 98 +/- 7 mg/dL in the control and transplanted groups, respectively. WBGP was increased by 42 per cent in the transplanted group (2.54 +/- 0.17 vs 3.62 +/- 0.39 mg/kg.min), but the net hepatic glucose output was not different between the control and the transplanted groups (1.53 +/- 0.28 vs 1.68 +/- 0.31 mg/kg.min). These results demonstrate that net hepatic glucose output was not different between the control and transplanted pigs, suggesting that LT does not compromise the ability of the liver to produce glucose. However, the WBGP was increased by 42 per cent in the transplanted group, suggesting either a significant contribution from another organ or a significant intrahepatic utilization of glucose.

Clinical experience with cryosurgery for advanced hepatobiliary tumors

INTRODUCTION

There have been reports that suggest cryosurgical techniques may be a useful adjunct to surgical resection or even a viable alternative treatment for hepatobiliary malignancies. Our objective was to evaluate the clinical results following cryoablation in conjunction with surgical resection for advanced hepatic tumors.

MATERIALS AND METHODS

Thirty-two consecutive procedures in 31 patients with advanced liver tumors treated with cryosurgical ablation were evaluated. Cryosurgery was applied: (1) to achieve a > 1-cm tumor-free margin when standard surgical margins were close (2) with or without standard surgical resection to manage multiple tumors (3) with hepatic arterial portocath placement to increase tumor response. Cryoablation was applied to 47 of 105 lesions--independently in 4 patients and in combination with hepatic resection in 28 procedures.

RESULTS

Cryoablation was used in 11 procedures because of close surgical margins. In 21 operations cryosurgery was used for primary ablation. In 17 of these 21 patients both cryosurgery and resection were used for different lesions; in 4 cryosurgery alone was used. Transient changes in hepatic enzymes, PT, PTT, and platelets were at maximum on Postoperative Days 1-3. Surgical mortality and morbidity rates were 6 and 60%, respectively. Coagulation abnormalities were common: at least 30% reduction in platelets occurred in all patients and greater than a 50% reduction occurred in 19 of 32 (59%). Twenty patients had a PT > 15 s and 6 of these 20 also had a platelet count < 50,000. Associated complications included one wound hematoma, two GI hemorrhages, one intracranial hemorrhage, and one hepatic hemorrhage from the cryosurgical site. The actuarial patient survivals were 90, 59, 33, and 22% at 6, 12, 24, and 36 months, respectively.

CONCLUSIONS

This report helps define the risks and results of cryosurgical ablation as a complement to surgical resection for advanced hepatobiliary tumors. Management of lesions contiguous to major blood vessels may include either the Pringle maneuver or total vascular isolation. Since these procedures can have significant morbidity, we urge cautious application of cryosurgery for advanced hepatobiliary tumors in selected otherwise unresectable patients.

Hepatic uptake of amino acids immediately after liver transplantation is well preserved despite altered plasma profiles

BACKGROUND

The liver is one of the principal organs responsible for the uptake and release of amino acids in the body. The ability of the transplanted liver to clear plasma amino acids is associated with a functioning allograft. However, clinical assessment is limited by the inability to access the portal vein postoperatively. Therefore, using a porcine liver transplant model, we examined (1) the plasma levels of amino acids presented to the new hepatic allograft and (2) the capacity of the new allograft to clear these amino acids from the circulation.

MATERIALS AND METHODS

Two groups of commercially bred pigs were studied: a control group (n = 8) underwent laparotomy and a transplanted group (n = 6) underwent orthotopic liver transplantation (LT) using veno-venous bypass. All pigs had catheters placed in the carotid artery and portal and hepatic veins and ultrasonic transit time flow probes placed around the hepatic artery and portal vein. Plasma profiles of 23 amino acids were analyzed by high-pressure liquid chromatography. Hepatic balances of amino acids, using arteriovenous difference techniques coupled with hepatic blood flows, were also analyzed on postoperative day 1.

RESULTS

Neither portal vein blood flow (703 +/- 74 ml/min vs 666 +/- 82 ml/min) nor hepatic artery blood flow (322 +/- 43 ml/min vs 209 +/- 59 ml/min) was significantly different between the control and the transplanted groups, respectively. The transplanted group had significantly increased plasma levels of alanine (135 +/- 13 mumol/l vs 382 +/- 72 mumol/l), hydroxyproline (30 +/- 5 mumol/l vs 60 +/- 9 mumol/l), methionine (25 +/- 2 mumol/l vs 55 +/- 10 mumol/l), ornithine (36 +/- 5 mumol/l vs 141 +/- 33 mumol/l), phenylalanine (84 +/- 5 mumol/l vs 120 +/- 12 mumol/l), threonine (75 +/- 9 mumol/l vs 159 +/- 27 mumol/l), and tryptophan (17 +/- 2 mumol/l vs 31 +/- 4 mumol/l). The transplanted group also had significantly decreased plasma levels of isoleucine (122 +/- 12 mumol/l vs 85 +/- 8 mumol/l) and taurine (71 +/- 7 mumol/l vs 35 +/- 7 mumol/l). These individual amino acid changes were not accompanied by impairment in the net hepatic amino acid balance or the hepatic fractional extraction of amino acids between the two groups.

CONCLUSION

These results suggest that the circumstances associated with liver transplantation alter the fasting amino acid profile immediately postoperatively. However, liver transplantation does not impair the normal hepatic allograft uptake of most plasma amino acids. Thus, the changes observed in the circulating levels of amino acids may represent alterations in nonhepatic production and/or utilization. Furthermore, altered plasma amino acid profiles following liver transplantation are not necessarily indicative of impaired hepatic allograft amino acid metabolism.

Staging recurrent metastatic colorectal carcinoma with PET

Accurate detection of recurrent colorectal carcinoma remains a diagnostic challenge. The purposes of this study were to assess the accuracy of 18FDG-PET in patients with recurrent colorectal carcinoma in detecting liver metastases compared with computed tomography (CT) and CT portography, detecting extrahepatic metastases compared with CT and evaluating the impact on patient management.

METHODS

Fifty-two patients previously treated for colorectal carcinoma presented on 61 occasions with suspected recurrence and underwent 18FDG-PET of the entire body. PET, CT and CT portography images were analyzed visually. The final diagnosis was obtained by pathology (n = 44) or clinical and radiological follow-up (n = 17). The impact on management was reviewed retrospectively.

RESULTS

A total of 166 suspicious lesions were identified. Of the 127 intrahepatic lesions, 104 were malignant, and of the 39 extrahepatic lesions, 34 were malignant. Fluorine-18-fluorodeoxyglucose imaging was more accurate (92%) than CT and CT portography (78% and 80%, respectively) in detecting liver metastases and more accurate than CT for extrahepatic metastases (92% and 71%, respectively). Fluorine-18-fluorodeoxyglucose detected unsuspected metastases in 17 patients and altered surgical management in 28% of patients.

CONCLUSION

These data identify that 18FDG-PET is the most accurate noninvasive method for staging patients with recurrent metastatic colorectal carcinoma and plays an important role in management decisions in this setting.

Mechanisms of hyperinsulinemia and hyperglucagonemia after liver transplantation

These studies were undertaken to evaluate the mechanisms for changes in plasma insulin and glucagon levels observed post-liver transplantation. Two groups of pigs were studied: a control group (n = 8) underwent laparotomy and catheter placement in the carotid artery and portal and hepatic veins. Hepatic blood flow was measured by ultrasonic flow probes placed around the hepatic artery and portal vein. An experimental group (n = 8) underwent orthotopic liver transplantation and similar instrumentation. On Day 1 after surgery, an estimate of insulin and glucagon secretion and hepatic extraction was determined using arteriovenous difference techniques. Serum assays were performed for markers of hepatic and renal function. Plasma insulin levels of the transplanted pigs were higher in the carotid artery (4 +/- 1 microU/ml vs 7 +/- 1 microU/ml), but not in the hepatic vein (5 +/- 1 microU/ml vs 7 +/- 1 microU/ml) and in the portal vein (10 +/- 2 microU/ml vs 12 +/- 2 microU/ml). Arterial plasma C-peptide was significantly greater in the transplanted group (0.23 +/- 0.02 ng/ml vs 0.42 +/- 0.03 ng/ml); however, the molar ratio of C-peptide and insulin was not different between the two groups (3.6 +/- 0.9 vs 3.4 +/- 0.4). Plasma glucagon levels of the transplanted pigs were significantly elevated in the carotid artery (111 +/- 11 pg/ml vs 323 +/- 65 pg/ml), portal vein (221 +/- 27 pg/ml vs 495 +/- 69 pg/ml), and hepatic vein (142 +/- 15 pg/ml vs 395 +/- 58 pg/ml). The estimate of pancreatic secretion of insulin (115 +/- 28 microU/kg.min) vs 71 +/- 21 microU/kg.min) and glucagon (2.0 +/- 0.4 ng/kg.min vs 2.7 +/- 0.7 ng/kg.min) and the fractional hepatic extraction rate of insulin (35 +/- 8% vs 32 +/- 5%) were not different between the two groups. However, the hepatic fractional extraction rate of glucagon was significantly decreased in the transplanted group (25 +/- 5% vs 11 +/- 3%). Therefore, the hyperglucagonemia observed 24 hr following liver transplantation is partly due to reduced hepatic fractional extraction of glucagon while the hyperinsulinemia is mainly due to the nonhepatic clearance of insulin. We speculate that decreased renal function may contribute to the hyperinsulinemia, elevated C-peptide concentrations, and hyperglucagonemia.

Recurrent gallbladder carcinoma at laparoscopy port sites diagnosed by positron emission tomography: implications for primary and radical second operations

Inapparent gallbladder carcinoma discovered by histologic examination following 1 per cent of cholecystectomies generates a difficult clinical problem. There is evidence that radical resection can prolong survival, especially for locally advanced (> or = PT2, according to the Union International Centre Cancer pathologic T classification) lesions. Case reports of recurrence at port sites after laparoscopic cholecystectomy add another aspect to the management difficulty. A 64-year-old woman underwent laparoscopic cholecystectomy for biliary colic. Histologic evaluation revealed an incidental adenocarcinoma, stage pT3. Radical resection with curative intent occurred 11 days later, including mesohepatectomy, skeletonization resection of the common bile duct with en bloc lymph node dissection, and bilateral Roux-en-Y hepaticojejunostomies. There was no tumor identified in the re-excision specimen (T3N0M0). At 7-month follow-up, the patient presented with nodules in the right subcostal area and in the periumbilical incision. Positron emission tomography demonstrated carcinoma at both sites. Biopsy confirmed metastatic gallbladder carcinoma. This case emphasizes the significance of tumor seeding at port sites during laparoscopy. An open technique is indicated if carcinoma is suspected. To avoid dissemination of unsuspected carcinoma during routine laparoscopic procedures, isolation techniques must be applied. The benefit of radical resection was clearly thwarted in this case, and resection of port sites at the time of reoperation is warranted. Finally, positron emission tomography scan is useful in delineating the recurrence of gallbladder carcinoma and its extent.

Nashville experience with liver transplantation in Veterans Administration patients

In this study, we compared results of 28 liver transplants performed in 25 patients referred through the Veterans Administration with 82 transplants performed in 75 nonveteran patients. The evaluation and follow-up care was provided by the same team of physicians and nurses and the transplant procedure performed in the same hospital for both patient groups. There was a significantly greater incidence of hepatitis C and/or previous alcohol abuse in veteran compared with non-VA patients [23/25 (92%) vs 29/75 (39%); P < 0.05] and a greater incidence of native portal vein thrombosis [6/25 (24%) vs 2/75 (2.6%); P < 0.01], but no difference in Child's-Pugh score (10.8 vs 9.9) or UNOS listing status (mean status 2.7 vs 2.8). The increased incidence of native portal vein thrombosis did not appear to be solely related to previous alcohol abuse or hepatitis C, since only 1 of 29 (3.4%) non-VA patients with these etiologies had this finding. There was no difference in patient or graft survival between the VA and non-VA groups with overall actuarial 6-, 12-, and 18-month patient survival of 86, 84, and 83% and graft survival of 80, 78, and 77%. There was no difference in major complication rates but there was a significantly longer average hospital stay (27 +/- 31 vs 18 +/- 12 days; P < 0.05) in the VA compared with non-VA group. One patient with native portal vein thrombosis in the non-VA group developed portal vein thrombosis in the postoperative period. There was no documented recidivism in any patient with a history of prior substance abuse in either group. This study confirms that veteran patients have a higher incidence of hepatitis C and previous alcohol abuse as causes of liver disease, have a higher incidence of native portal vein thrombosis, and have longer mean hospital stays, but experience the same survival in the first 18 months compared with nonveteran patients.

A model for the extended studies of hepatic hemodynamics and metabolism in swine

To our knowledge postoperative hepatic hemodynamics and hepatic metabolism have not been fully studied on a long-term basis. Our goal was to develop a large animal model that would permit the measurement of hepatic blood flow (BF), perihepatic pressures (P), and hepatic metabolism in a long-term setting. Catheters were inserted into the jugular vein, carotid artery, pulmonary artery, hepatic vein, and portal vein (PV) of 27 commercially bred pigs; ultrasonic transit time flowmeter probes were placed around the hepatic artery and PV. Daily postoperative measurements of jugular vein P, carotid artery P, pulmonary artery P, hepatic vein P, and PVP, as well as hepatic artery BF and PVBF, were recorded for 20 days. Hepatic carbohydrate metabolism was assessed by arteriovenous difference techniques. Jugular vein P, pulmonary artery P, hepatic vein P, PVP, and heart rate reached steady-state values during the first week, with a mean +/- SEM of 1.0 +/- 0.3 mm Hg for jugular vein P, 21.4 +/- 2.1 mm Hg for pulmonary artery P, 4.3 +/- 0.4 mm Hg for HVP, 7.8 +/- 0.5 mm Hg for PVP, and 116 +/- 4 beats per minute for heart rate. Mean carotid artery P increased from 65 +/- 3 mm Hg during surgery to 94 +/- 2 mm Hg on postoperative day 1 (P < 0.001) and to a mean 101 +/- 2 mm Hg thereafter. Total hepatic BF reached a steady-state value of 1,132 +/- 187 ml/min by postoperative day 7 (P = 0.19). Over week 1 hepatic artery BF measured as a percentage of total hepatic BF decreased from 35.0 +/- 3.0% to 15.5 +/- 2.7%, and PVBF increased from 65.0 +/- 3.0% to 84.5 +/- 2.7% (P < 0.005); both variables were steady thereafter. In the hemodynamic steady state the net hepatic balances of glucose, lactate, glycerol, and alanine in 5 pigs were 9.9 +/- 4.0, -4.2 +/- 0.4, -2.3 +/- 1.1, and -0.68 +/- 0.22 micromol/kg per min respectively. The net gut (portal-drained viscera) balances of glucose, lactate, alanine, and glycerol were -2.0 +/- 2.5, 1.1 +/- 0.5, 0.73 +/- 0.18, and -0.69 +/- 0.19 micromol/kg per min respectively. Thus, a reliable large animal model was developed to study acute and chronic hepatic hemodynamics and metabolism.