Jeremy Lipschitz

Long-Term Outcomes Following Hepatic Resection and Radiofrequency Ablation of Colorectal Liver Metastases

Recently some have called for randomized controlled trials comparing RFA to hepatic resection, particularly for patients with only a few small metastases. The objectives were to compare local recurrence and survival following RFA and hepatic resection for colorectal liver metastases. This was a retrospective review of open RFA and hepatic resection for colorectal liver metastases between January 1998 and May 2007. All patients who had RFA were considered to have unresectable disease. 58 patients had hepatic resection and 43 had RFA. A 5-year survival after resection was 43% compared to 23% after RFA. For patients with solitary lesions, a 5-year survival was 48% after resection and 15% after RFA. Sixty percent of patients suffered local recurrences after RFA compared to 7% after hepatic resection. RFA is inferior to resection. The results observed in this study support the consensus that RFA cannot be considered an equivalent procedure to hepatic resection.

Decreased hepatocyte membrane potential differences and GABAa‐β3 expression in human hepatocellular carcinoma

To determine whether hepatocyte membrane potential differences (PDs) are depolarized in human HCC and whether depolarization is associated with changes in GABAA receptor expression, hepatocyte PDs and γ‐aminobutyric acid (GABA)A receptor messenger RNA (mRNA) and protein expression were documented in HCC tissues via microelectrode impalement, real‐time reverse‐transcriptase polymerase chain reaction, and Western blot analysis, respectively. HCC tissues were significantly depolarized (−19.8 ± 1.3 versus −25.9 ± 3.2 mV, respectively [P < 0.05]), and GABAA‐β3 expression was down‐regulated (GABAA‐β3 mRNA and protein expression in HCC; 5,693 ± 1,385 and 0.29 ± 0.11 versus 11,046 ± 4,979 copies/100 mg RNA and 0.62 ± 0.16 optical density in adjacent tumor tissues, respectively [P = 0.002 and P < 0.0001, respectively]) when compared with adjacent nontumor tissues. To determine the physiological relevance of the down‐regulation, human malignant hepatocytes deficient in GABAA‐β3 receptor expression (Huh‐7 cells) were transfected with GABAA‐β3 complementary DNA (cDNA) or vector alone and injected into nu/nu nude mice (n = 16‐17 group). Tumors developed after a mean (± SD) of 51 ± 6 days (range: 41‐60 days) in 7/16 (44%) mice injected with vector‐transfected cells and 70 ± 12 days (range: 59‐86 days) in 4/17 (24%) mice injected with GABAA‐β3 cDNA‐transfected cells (P < 0.005). Conclusion: The results of this study indicate that (1) human HCC tissues are depolarized compared with adjacent nontumor tissues, (2) hepatic GABAA‐β3 receptor expression is down‐regulated in human HCC, and (3) restoration of GABAA‐β3 receptor expression results in attenuated in vivo tumor growth in nude mice. (HEPATOLOGY 2007;45:735–745.)

Immediate-Early Protooncogene Expression and Liver Function Following Various Extents of Partial Hepatectomy in the Rat

Immediate–early protooncogenes (IEP) are thought to play an important role in hepatocyte replication. Whether the extent of their expression correlates with the strength of the proliferative stimulus and subsequent regenerative activity has yet to be documented in vivo. Data are also lacking with respect to the level at which liver disease is associated with biochemical evidence of hepatic dysfunction. Thus, the objectives of this study were to determine whether a correlation exists between IEP gene mRNA expression and varying extents of partial hepatectomy (PHx) and to document the extent of resection required to result in increases in serum bilirubin levels. Eighty-nine adult, male Sprague-Dawley rats underwent either sham surgery or 20%, 35%, 55%, 70% or 90% PHx. Postoperatively, rats were killed (N = 3–6/group) at 15 and 30 mins and 8 and 24 hrs for c-fos, c-jun, and c-myc mRNA expression by northern blot analyses. Rats killed at 24 hrs also had hepatic regenerative activity documented by [3H]thymidine incorporation into hepatic DNA and serum bilirubin determinations. While c-fos mRNA expression at 15 mins and c-myc mRNA expression at 8 hrs after PHx did not correlate with the extent of PHx (r2 = 0.478 and 0.018, respectively), a weak correlation existed between c-jun mRNA expression at 30 mins and the extent of PHx (r2 = 0.662, P < 0.05). In terms of IEP mRNA expression and hepatic regenerative activity, a strong correlation existed between c-fos mRNA expression and [3H]thymidine incorporation (r2 = 0.851, P < 0.01) but not c-jun or c-myc mRNA expression. Compared to sham operated controls, [3H]thymidine incorporation was 2.0×, 3.4×, 3.2×, 7.8×, and 2.2× increased following 20%, 35%, 55%, 70%, and 90% PHx, respectively. Serum bilirubin levels remained unchanged until 70% PHx, when they increased from baseline values of 0.54 ± 0.05 mg/dl to 1.02 ± 0.15 mg/dl (P < 0.05). A further increase occurred following 90% PHx (1.83 ± 0.30 mg/dl, P < 0.01). In conclusion these findings indicate that c-fos mRNA expression 15 mins after PHx correlates with hepatic regenerative activity but not the strength of the regenerative stimulus and that hepatic parenchymal loss of 55–70% must occur prior to the detection of elevated serum bilirubin levels. The results also indicate that relative to a 70% PHx, 90% PHx is associated with decreased rather than increased hepatic regenerative activity.

The effects of various organ preservation solutions on hepatocyte membrane potentials, intracellular calcium concentrations, and outcome following liver transplantation.

BACKGROUND Hepatocyte membrane potential differences (PDs) may be altered by the preservation solutions used in liver transplantation. Such alterations could impact on the survival of the donor liver, extent of biochemical injury, and flux of important ionic compounds. The purpose of the present study was to document these outcomes in the presence of four different preservation solutions. METHODS Livers of adult male Sprague-Dawley rats (N = 3 to 4 per group) were impaled with intracellular microelectrodes prior to and at various time periods for 6 hours following complete hepatic resection. Just prior to resection, each liver was perfused with preservation solutions associated with high (normal saline [NS]), moderate (Euro-Collins [EC]), and low (University of Wisconsin solution [UW]) risks of reperfusion injury. RESULTS Baseline (in situ) PDs were similar in all groups (-37 +/- 4 mV, mean +/- SD). Ten minutes postresection, hepatic PDs were as follows: NS, -23.8 +/- 3.5 mV; EC, -11.4 +/- 0.4 mV; and UW, -8.7 +/- 0.3 mV (P <0.01 for all groups). Maximum depolarization occurred at 6 hours postresection (NS, -8.1 +/- 1.1 mV; EC, -7.7 +/- 1.3 mV; and UW, -8.6 +/- 1.0 mV). To determine whether these changes are of pathophysiologic importance, the NS solution was modified (addition of 0.1% ethanol) to achieve similar PD changes as those observed with UW. Liver transplants were then performed where the donor livers had been perfused and preserved for 6 hours with either NS or the modified NS (MNS) solution. Posttransplant (10 day) survival was 1 of 6 (17%) in the NS group and 4 of 6 (67%) in the MNS group (P <0.05). Regarding the effects of PD changes on ionic flux, intracellular calcium levels were documented for up to 4 hours by fluorescence video microscopy using Fura-2 in isolated hepatocytes exposed to NS, UW, and MNS solutions. Intracellular calcium levels were similar in all solutions at each time point studied. CONCLUSIONS The results of this study indicate that hepatocytes undergo prompt and marked depolarization following hepatic resection, and the extent of the depolarization correlates with survival following transplantation.

Multifocal gastric neoplasia after recurrent laser therapy for the watermelon stomach

Repeated laser therapy has become an accepted therapeutic approach in the treatment of watermelon stomach, and to date no important negative sequelae have been reported. The case of a patient who underwent repeated sessions of neodymium: yttrium aluminum garnet (Nd:YAG) laser therapy over a five-year period for the treatment of the watermelon stomach is presented. Postlaser therapy the patient developed deep ulcerations that would heal; however, he ultimately developed a nodular antrum. Random biopsies of antral nodules revealed carcinoma-in-situ. A Billroth I gastrectomy revealed two foci of carcinoma-in-situ/high grade dysplasia and multiple foci of lower grades of dysplasia. This case suggests a possible association between use of laser therapy and development of gastric neoplasia.

GABA-B receptor activation inhibits the in vitro migration of malignant hepatocytes

There are conflicting data regarding whether activation of γ-aminobutyric acid-B (GABA-B) receptors results in inhibition of tumor growth and invasion. The objectives of this study were to document the effects of the GABA-B receptor agonist baclofen on malignant hepatocyte proliferation and migration. We also sought to determine whether any effects on cell migration were mediated by changes in cyclic adenosine monophosphate (cAMP) signaling or matrix metalloproteinase (MMP) expression. Finally, GABA-B(1) and -B(2) receptor expression was documented in 2 malignant hepatocyte cell lines (PLC/PRF/5 and Huh-7) and 12 sets of human hepatocellular carcinoma and adjacent nontumor tissues. Cell proliferative activity was documented by WST-1 absorbance, migration by wound healing assays, cAMP levels by enzyme-linked immunoassay (ELISA), MMP by immunohistochemistry and ELISA, and GABA-B receptor expression by flow cytometry and reverse transcriptase - polymerase chain reaction. Although baclofen had no effect on cell proliferation, wound healing was delayed, an effect that was reversed by the GABA-B receptor antagonist CGP. cAMP levels were decreased in Huh-7 but not PLC cells exposed to baclofen. MMP expression remained unaltered in both cell lines. Finally, GABA-B(1) receptor expression was present and consistently expressed, but GABA-B(2) expression was limited and varied with the number of cell passages and (or) duration of culture. In conclusion, activation of GABA-B receptors has no effect on malignant hepatocyte proliferation but does decrease cell migration. This inhibitory effect may involve cAMP signaling but not MMP expression. GABA-B(2) receptor expression is limited and variable, which may help to explain discrepancies with previously published results.

Physician attitudes and treatment patterns for pancreatic cancer

BackgroundSurgery appears to be an underutilized treatment option for pancreatic cancer. Nihilistic physician attitudes may be partly responsible. The study objectives were to analyze physician attitudes towards this disease and determine treatment patterns and outcomes including rates of surgical referral.MethodsA survey was administered to 420 physicians in Manitoba to document general knowledge and attitudes. Population based administrative data was accessed for all patients diagnosed with pancreatic cancer between 2004 and 2006 to examine treatment patterns and outcomes.Results181 physicians responded to the survey. Most (73%) believed that surgical resection was worthwhile. Of the 413 Manitobans diagnosed with pancreatic cancer, only 11% underwent an attempt at surgical resection. There were 124 patients with stage I or II disease (i.e. potentially resectable), 85 of these patients received no treatment and 39% were not referred to a surgeon. These patients were older than those referred, but did not have more comorbidities.ConclusionMost physicians were insightfully aware of both the survival benefit and potential risks of surgical resection. However, some did overestimate the surgical mortality and underestimate the associated survival benefit. Although advanced age may justly account for some of the patients not receiving a referral, it is reasonable to assume that nihilistic physician attitudes is contributing to the apparent underutilization of surgery for pancreatic cancer. Efforts should be made to ensure that eligible patients are at least offered surgery as a potential treatment option.

The Effects of Colectomy on Immediate–Early Proto-Oncogene Expression and Hepatic Regeneration in the Rat

The intact liver exists in a state of replicative quiescence. The factor(s) responsible for maintaining this state and their tissue sources have yet to be identified. Because the colon synthesizes and/or absorbs numerous agents that inhibit hepatocyte proliferation, the principle purpose of this study was to determine whether total colectomy would result in the conversion of quiescent livers to a state of replicative competence. Thus, adult, male Sprague-Dawley rats (250–300 g) were randomized to undergo either total colectomy with ileostomy or sham surgery. Thereafter, rats were sacrificed (N = 3–6/group) at times 15 and 30 min and 1, 2, 6, and 24 hr and the livers analyzed by Northern blot analyses for mRNA of the following immediate–early proto-oncogenes (IEP genes): c-fos, c-jun, and c-myc. Rats sacrificed at 24 hr also had hepatic regenerative activity documented by [3H]thymidine incorporation into hepatic DNA. The results of the study revealed that within 15 min, c-fos and c-jun mRNA expression increased in colectomized rats, with peak expression occurring at 30 and 60 min, respectively. c-myc mRNA expression was more delayed, with peak expression occurring at 6 hr postcolectomy. IEP gene expression also increased somewhat in sham-colectomy controls but the increases were not as prompt and, in general, were of lower magnitude than those in the colectomy group. Despite the differences in IEP gene expression between the two groups, [3H]thymidine incorporation at 24 hr was similar (mean ± SE: colectomy group, 17.2 ± 2.6 dpm/μ g DNA; sham-colectomy controls, 14.8 ± 1.4 dpm/μg DNA). To determine whether the increases in IEP gene expression expedite or augment the hepatic regenerative response to partial hepatectomy (PHx), rats that had undergone colectomy or sham colectomy 1 hr earlier and rats with no previous abdominal surgery then underwent a 70% PHx and were sacrificed at 8, 16, and 24 hr thereafter. At each time interval, [3H]thymidine incorporation was documented and found to be similar in the three groups. In conclusion, the results of this study indicate that total colectomy, and to a lesser extent abdominal surgery, induces the conversion of an intact, quiescent liver to a state of replicative competence. The results also suggest that, in addition to colectomy, the presence of mitogens and/or co-mitogens is required for further progression of hepatocytes through the cell cycle. Finally, a “primed” liver does not respond more promptly or vigorously to a regenerative stimulus than a “resting” liver.

Transforming growth factor-β (TGF-β) protein levels are not elevated in the blood or bile of patients with primary sclerosing cholangitis: A pilot study

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disorder of unknown etiology characterized by progressive fibrosis and stricturing of the biliary tract. Transforming growth factor-β (TGF-β) is a family of cytokines produced by biliary tract epithelial cells that promote fibrinogenesis. Our objective was to determine whether TGF-β levels are increased in the blood and/or bile of PSC patients compared to patients with other causes of obstructed biliary tracts (controls). Serum and bile TGF-β levels were documented by enzyme-linked immunoassay in 10 adult PSC and 10 control patients obtained at the time of endoscopic retrograde cholangiography. Serum and bile TGF-β levels were similar in the two groups (PSC versus control sera, 33.4 ± 4.3 versus 27.5 ± 7.7 ng/ml, and bile, 367 ± 275 versus 457 ± 247 ng/mg, respectively). Serum and bile TGF-β levels are not increased in patients with PSC. Hence, the results of this pilot study do not support the hypotheses that PSC is caused by dysregulated TGF-β expression.

Blastomycosis presenting as multiple splenic abscesses: Case report and review of the literature

A 31-year-old Canadian Aboriginal man from northwestern Ontario presented with left upper quadrant pain and a tender left upper quadrant mass. Evaluation with a computed tomography scan showed multiple lesions within the spleen, a collection between the splenic tip and splenic flexure of the colon, and several small adrenal lesions. Computed tomographic-guided needle biopsy showed necrotizing granulomatous inflammation and multinucleated giant cells. Gomoris methenamine silver stain showed broad-based budding yeast consistent with Blastomyces dermatitidis. Abdominal symptoms resolved after two months of oral itraconazole. Multiple splenic abscesses are a rare presentation of blastomycosis and should be considered in the differential diagnosis of left upper quadrant abdominal pain in a patient with a history of travel or residence in a region endemic for B dermatitidis.