Exploring Potential Epigenetic Biomarkers for Colorectal Cancer Metastasis

Metastatic progression is a complex, multistep process and the leading cause of cancer mortality. There is growing evidence that emphasises the significance of epigenetic modification, specifically DNA methylation and histone modifications, in influencing colorectal (CRC) metastasis. Epigenetic modifications influence the expression of genes involved in various cellular processes, including the pathways associated with metastasis. These modifications could contribute to metastatic progression by enhancing oncogenes and silencing tumour suppressor genes. Moreover, specific epigenetic alterations enable cancer cells to acquire invasive and metastatic characteristics by altering cell adhesion, migration, and invasion-related pathways. Exploring the involvement of DNA methylation and histone modification is crucial for identifying biomarkers that impact cancer prediction for metastasis in CRC. This review provides a summary of the potential epigenetic biomarkers associated with metastasis in CRC, particularly DNA methylation and histone modifications, and examines the pathways associated with these biomarkers.

An epigenetic signature of advanced colorectal cancer metastasis

Colorectal cancer (CRC) is a leading cause of morbidity and mortality worldwide. The majority of CRC deaths are caused by tumor metastasis, even following treatment. There is strong evidence for epigenetic changes, such as DNA methylation, accompanying CRC metastasis and poorer patient survival. Earlier detection and a better understanding of molecular drivers for CRC metastasis are of critical clinical importance. Here, we identify a signature of advanced CRC metastasis by performing whole genome-scale DNA methylation and full transcriptome analyses of paired primary cancers and liver metastases from CRC patients. We observed striking methylation differences between primary and metastatic pairs. A subset of loci showed coordinated methylation-expression changes, suggesting these are potentially epigenetic drivers that control the expression of critical genes in the metastatic cascade. The identification of CRC epigenomic markers of metastasis has the potential to enable better outcome prediction and lead to the discovery of new therapeutic targets.

Portal vein embolization with absolute ethanol to induce hypertrophy of the future liver remnant

Background

Preoperative portal vein embolization (PVE) is widely used prior to major liver resection to reduce the risk of post-hepatectomy liver failure (PHLF). We evaluated the efficacy and safety of PVE using absolute ethanol.

Methods

Consecutive patients undergoing preoperative PVE between February 2003 and February 2020 at a high-volume tertiary institution were retrospectively reviewed. Hypertrophy of the future liver remnant (FLR) was determined by comparing volumetric data using semi-automated software on computed tomography or magnetic resonance imaging before and after PVE. Efficacy of absolute ethanol was evaluated by the percentage increase in the FLR volume and the ratio of the FLR to the total liver volume (TLV). Technical success and complications following PVE were evaluated. Feasibility of hepatectomy following PVE and the incidence of PHLF were determined.

Results

Sixty-two patients underwent preoperative PVE using absolute ethanol. The technical success rate was 95.2%. Median time interval between PVE and follow-up imaging was 34 days (range 6–144 days). The mean increase in FLR volume and ratio of the FLR to TLV were 43.6 ± 34.4% and 12.3 ± 7.7% respectively. Major adverse events occurred in 3 cases (4.8%) and did not preclude consideration of surgery. Forty-two patients (67.8%) proceeded to surgery for intended hepatectomy of which 36 patients (58.1%) underwent liver resection. Major post-operative complications occurred in 4 patients (11.1%) and there were no cases of PHLF.

Conclusion

Preoperative PVE with absolute ethanol is effective and safe in inducing hypertrophy of the FLR before partial hepatectomy to prevent PHLF.

Strategies for Antibiotic Administration for Bowel Preparation Among Patients Undergoing Elective Colorectal Surgery: A Network Meta-analysis

Importance

There are discrepancies in guidelines on preparation for colorectal surgery. While intravenous (IV) antibiotics are usually administered, the use of mechanical bowel preparation (MBP), enemas, and/or oral antibiotics (OA) is controversial.

Objective

To summarize all data from randomized clinical trials (RCTs) that met selection criteria using network meta-analysis (NMA) to determine the ranking of different bowel preparation treatment strategies for their associations with postoperative outcomes.

Data Sources

Data sources included MEDLINE, Embase, Cochrane, and Scopus databases with no language constraints, including abstracts and articles published prior to 2021.

Study Selection

Randomized studies of adults undergoing elective colorectal surgery with appropriate aerobic and anaerobic antibiotic cover that reported on incisional surgical site infection (SSI) or anastomotic leak were selected for inclusion in the analysis. These were selected by multiple reviewers and adjudicated by a separate lead investigator. A total of 167 of 6833 screened studies met initial selection criteria.

Data Extraction and Synthesis

NMA was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Data were extracted by multiple independent observers and pooled in a random-effects model.

Main Outcomes and Measures

Primary outcomes were incisional SSI and anastomotic leak. Secondary outcomes included other infections, mortality, ileus, and adverse effects of preparation.

Results

A total of 35 RCTs that included 8377 patients were identified. Treatments compared IV antibiotics (2762 patients [33%]), IV antibiotics with enema (222 patients [3%]), IV antibiotics with OA with or without enema (628 patients [7%]), MBP with IV antibiotics (2712 patients [32%]), MBP with IV antibiotics with OA (with good IV antibiotic cover in 925 patients [11%] and with good overall antibiotic cover in 375 patients [4%]), MBP with OA (267 patients [3%]), and OA (486 patients [6%]). The likelihood of incisional SSI was significantly lower for those receiving IV antibiotics with OA with or without enema (rank 1) and MBP with adequate IV antibiotics with OA (rank 2) compared with all other treatment options. The addition of OA to IV antibiotics, both with and without MBP, was associated with a reduction in incisional SSI by greater than 50%. There were minimal differences between treatments in anastomotic leak and in any of the secondary outcomes.

Conclusions and Relevance

This NMA demonstrated that the addition of OA to IV antibiotics were associated with a reduction in incisional SSI by greater than 50%. The results support the addition of OA to IV antibiotics to reduce incisional SSI among patients undergoing elective colorectal surgery.

A meta-epidemiological study of bias in randomized clinical trials of open and laparoscopic surgery

BACKGROUND

Blinding, random sequence generation, and allocation concealment are established strategies to minimize bias in RCTs. Meta-epidemiological studies of drug trials have demonstrated exaggerated treatment effects in RCTs where such methods were not employed. As blinding is more difficult in surgical trials it is important to determine whether this applies to them. The study aimed to investigate this using systematic meta-epidemiological methods.

METHOD

The Cochrane Database of Systematic Reviews was searched for systematic reviews of RCTs that compared laparoscopic and open abdominal surgical procedures. Each review was then scrutinized to determine whether at least one of the included trials was blinded. Eligible reviews were updated and individual RCTs retrieved. Extracted data included the primary outcomes of interest (length of stay and complications), secondary outcomes and a risk of bias assessment. A multistep meta-regression analysis was then performed to obtain an overall difference in the reported outcome differences between trials that employed each bias-minimization strategy, and those that did not.

RESULTS

Some 316 RCTs were included, reporting on eight different procedures. Patient-blinded RCTs reported a smaller difference in length of stay between laparoscopic and open groups (difference of standardized mean differences -0·36 (95 per cent c.i. -0·73 to 0·00)) and complications (ratio of odds ratios 0·76 (95 per cent c.i. 0·61 to 0·93)). Blinding of postoperative carers and outcome assessors had similar effects.

CONCLUSION

Lack of blinding significantly altered the treatment effect estimates of RCTs comparing laparoscopic and open surgery. Blinding should be implemented in surgical RCTs where possible to avoid systematic bias.

Human liver-derived MAIT cells differ from blood MAIT cells in their metabolism and response to TCR-independent activation

Mucosal associated invariant T (MAIT) cells are anti-microbial innate-like T cells that are abundant in blood and liver. MAIT cells express a semi-invariant T-cell receptor (TCR) that recognizes a pyrimidine ligand, derived from microbial riboflavin synthesis, bound to MR1. Both blood and liver derived (ld)-MAIT cells can be robustly stimulated via TCR or by cytokines produced during bacterial or viral infection. In this study, we compared the functional and transcriptomic response of human blood and ld-MAIT cells to TCR signals (Escherichia coli or the pyrimidine ligand) and cytokines (IL-12 + IL-18). While the response of blood and ld-MAIT cells to TCR signals were comparable, following cytokine stimulation ld-MAIT cells were more polyfunctional than blood MAIT cells. Transcriptomic analysis demonstrated different effector programmes of ld-MAIT cells with the two modes of activation, including the enrichment of a tissue repair signature in TCR-stimulated MAIT cells. Interestingly, we observed enhancement of IL-12 signaling and fatty acid metabolism in untreated ld-MAIT cells compared with blood MAIT cells. Additionally, MAIT cells from blood and liver were modulated similarly by TCR and cytokine signals. Therefore, we report that blood and ld-MAIT cells are fundamentally different but undergo conserved changes following activation via TCR or by cytokines.

The Epigenetic landscape of Circulating tumour cells

Cancer metastasis is the main reason for the high mortality in patients, contributing to 90% of cancer-related deaths. Biomarkers for early detection and therapeutic monitoring are essential to improve cancer outcomes. Circulating tumour cells (CTCs) arise from solid tumours and are capable of metastatic dissemination via the bloodstream or lymphatic system. Thus, CTCs can potentially be developed as a minimally invasive biomarker for early detection and therapeutic monitoring. Despite its clinical potential, research on CTCs remains limited, and this is likely due to their low numbers, short half-life, and the lack of robust methods for their isolation. There is also a need for molecular characterisation of CTCs to identify tumour-specific features, such as epigenetic signatures of metastasis. This review provides an overview of the epigenetic landscape of CTCs. We discuss the role of epigenetic modifications in CTC dissemination,metastatic tumour formation and progression and highlight its clinical implications.

Type I interferons are important co-stimulatory signals during T cell receptor mediated human MAIT cell activation

Mucosal associated invariant T (MAIT) cells are abundant unconventional T cells that can be stimulated either via their TCR or by innate cytokines. The MAIT cell TCR recognises a pyrimidine ligand, derived from riboflavin synthesising bacteria, bound to MR1. In infection, bacteria not only provide the pyrimidine ligand but also co-stimulatory signals, such as TLR agonists, that can modulate TCR-mediated activation. Recently, type I interferons (T1-IFNs) have been identified as contributing to cytokine-mediated MAIT cell activation. However, it is unknown whether T1-IFNs also have a role during TCR-mediated MAIT cell activation. In this study, we investigated the co-stimulatory role of T1-IFNs during TCR-mediated activation of MAIT cells by the MR1 ligand 5-amino-6-d-ribitylaminouracil/methylglyoxal. We found that T1-IFNs were able to boost interferon-γ and granzyme B production in 5-amino-6-d-ribitylaminouracil/methylglyoxal-stimulated MAIT cells. Similarly, influenza virus-induced T1-IFNs enhanced TCR-mediated MAIT cell activation. An essential role of T1-IFNs in regulating MAIT cell activation by riboflavin synthesising bacteria was also demonstrated. The co-stimulatory role of T1-IFNs was also evident in liver-derived MAIT cells. T1-IFNs acted directly on MAIT cells to enhance their response to TCR stimulation. Overall, our findings establish an important immunomodulatory role of T1-IFNs during TCR-mediated MAIT cell activation.

Prevalence of diabetes in liver cirrhosis: A systematic review and meta-analysis

An association between diabetes mellitus (DM) and liver cirrhosis is well-known, but estimates of the prevalence of DM in patients with liver cirrhosis vary widely. A systematic review was undertaken to determine the prevalence of DM in adult patients with liver cirrhosis. The Medline, EMBASE, and Cochrane Library databases were searched for peer-reviewed studies published in English (1979-2017) that investigated the prevalence of diabetes in adult patients with cirrhosis. Pooled estimates of prevalence of DM were determined for all eligible patients and according to aetiology and severity of liver disease. Fifty-eight studies satisfied criteria for inclusion, with 9705 patients included in the pooled prevalence analysis. The overall prevalence of DM was 31%. The prevalence of DM was highest in patients with nonalcoholic fatty liver disease (56%), cryptogenic (51%), hepatitis C (32%), or alcoholic (27%) cirrhosis. For assessing prevalence of DM as a function of severity of liver disease, evaluable data were available only for hepatitis C and hepatitis B cirrhosis. DM may be more prevalent in cirrhosis than previously thought. This has implications for prognosis and treatment in these patients.

Relationship Between Total Body Protein and Cross-Sectional Skeletal Muscle Area in Liver Cirrhosis Is Influenced by Overhydration

Sarcopenia as defined by reduced skeletal muscle area (SMA) on cross-sectional abdominal imaging has been proposed as an objective measure of malnutrition, and it is associated with both wait-list mortality and posttransplant complications in patients with cirrhosis. SMA, however, has never been validated against the gold standard measurement of total body protein (TBP) by in vivo neutron activation analysis (IVNAA). Furthermore, overhydration is common in cirrhosis, and its effect on muscle area measurement remains unknown. We aimed to examine the relationship between SMA and TBP in patients with cirrhosis and to assess the impact of overhydration on this relationship. Patients with cirrhosis who had undergone IVNAA and cross-sectional imaging within 30 days were retrospectively identified. Patients with significant clinical events between measurements were excluded. Psoas muscle area (PMA) and SMA at the level of the third lumbar vertebrae were determined. Total body water was estimated from a multicompartment model and expressed as a fraction of fat-free mass (FFM), as determined by dual-energy X-ray absorptiometry, to provide an index of hydration status. In total, 107 patients underwent 109 cross-sectional imaging studies (87 computed tomography; 22 magnetic resonance imaging) within 30 days of IVNAA. Median time between measurements was 1 day (IQR, -1 to 3 days). Between 43% and 69% of the cohort was identified as sarcopenic, depending on muscle area cutoff values used. TBP was strongly correlated with SMA (r = 0.78; P < 0.001) and weakly correlated with PMA (r = 0.49; P < 0.001). Multiple linear regression showed SMA was significantly and positively associated with FFM hydration (P < 0.001) independently of TBP. In conclusion, SMA is more closely related to TBP than is PMA, and it should be preferred as a measure of sarcopenia. Overhydration significantly affects the measurement of cross-sectional muscle area.

Prognostic roles for IL-2-producing and CD69+ T cell subsets in colorectal cancer patients

Tumor infiltrating T cells are a predictor of patient outcome in patients with colorectal cancer (CRC). However, many T cell populations have been associated with both poor and positive patient prognoses, indicating a need to further understand the role of different T cell subsets in CRC. In this study, the T cell infiltrate from the tumor and nontumor bowel (NTB) was examined in 95 CRC patients using flow cytometry and associations with cancer stage and disease recurrence made. Our findings showed that IFN-γ-producing T cells were associated with positive patient outcomes, and CD69⁺ T cells were associated with disease recurrence. Inflammatory (IL-17) and regulatory T cells were not associated with disease recurrence. Surprisingly, in a second cohort of 32 patients with long-term clinical follow up data, tumor infiltrating IL-2-producing T cells correlated negatively with disease free survival (DFS) and a higher frequency of IL-2-producing T cells was found in the NTB of patients with poorly differentiated tumors. These results point toward the possibility of a negative impact of IL-2 in tumor immune responses, which may influence future immunotherapy treatments in CRC patients.

Network meta-analysis of surgical management of gastro-oesophageal reflux disease in adults

BACKGROUND

Proton pump inhibitors are the mainstay of treatment for gastro-oesophageal reflux disease, but are associated with ongoing costs and side-effects. Antireflux surgery is cost-effective and is preferred by many patients. A total (360^o or Nissen) fundoplication is the traditional procedure, but other variations including partial fundoplications are also commonly performed, with the aim of achieving durable reflux control with minimal dysphagia. Many RCTs and some pairwise meta-analyses have compared some of these procedures but there is still uncertainty about which, if any, is superior. Network meta-analysis allows multiple simultaneous comparisons and robust synthesis of the available evidence in these situations. A network meta-analysis comparing all antireflux procedures was performed to identify which has the most favourable outcomes at short-term (3-12 months), medium-term (1-5 years) and long-term (10 years and more than 10 years) follow-up.

METHODS

Article databases were searched systematically for all eligible RCTs. Primary outcomes were quality-of-life measures and dysphagia. Secondary outcomes included reflux symptoms, pH studies and complications.

RESULTS

Fifty-one RCTs were included, involving 5357 patients and 14 different treatments. Posterior partial fundoplication ranked best in terms of reflux symptoms, and caused less dysphagia than most other interventions including Nissen fundoplication. This was consistent across all time points and outcome measures.

CONCLUSION

Posterior partial fundoplication provides the best balance of long-term, durable reflux control with less dysphagia, compared with other treatments.

Inclusion of BLIMP-1+ effector regulatory T cells improves the Immunoscore in a cohort of New Zealand colorectal cancer patients: a pilot study

Analysis of tumour-infiltrating T cells in colorectal cancer can predict disease-free survival. The Immunoscore, obtained by quantifying tumour-infiltrating CD3+ and CD8+ T cells, may improve current staging. Effector regulatory T cells are a potently suppressive subset in mice and, while present in human colorectal cancer, their role in patient outcome is unknown. Immunofluorescence was used to analyse immune cell infiltrates in patients with early (stage II) colorectal cancer with (n = 13) and without (n = 19) recurrent disease. CD3 and CD8 were used for the Immunoscore; FOXP3, BLIMP-1 and CD3 to identify effector regulatory T cells. Patients with high Immunoscores had increased disease-free survival compared to patients with low Immunoscores (Log-rank test p < 0.01). Prediction of outcome was further improved by stratifying patients with a low Immunoscore according to CD3+FOXP3+BLIMP-1+ cell infiltration at the invasive margin. Patients with a low Immunoscore and high infiltrate of CD3+FOXP3+BLIMP-1+ cells tended to have better disease-free survival than patients with low Immunoscore and low infiltrate of CD3+FOXP3+BLIMP-1+ cells. Patients with a high Immunoscore had better disease-free survival than patients with a low Immunoscore and low infiltrate of CD3+ FOXP3+ BLIMP-1+ cells (Log-rank test p < 0.001). These results indicate that tumour infiltration with effector regulatory T cells improves the prognostic value of the Immunoscore and implies that these cells may play a role in colorectal cancer patient outcome.

Genome-wide methylation analysis identifies a core set of hypermethylated genes in CIMP-H colorectal cancer

BACKGROUND

Aberrant DNA methylation profiles are a characteristic of all known cancer types, epitomized by the CpG island methylator phenotype (CIMP) in colorectal cancer (CRC). Hypermethylation has been observed at CpG islands throughout the genome, but it is unclear which factors determine whether an individual island becomes methylated in cancer.

METHODS

DNA methylation in CRC was analysed using the Illumina HumanMethylation450K array. Differentially methylated loci were identified using Significance Analysis of Microarrays (SAM) and the Wilcoxon Signed Rank (WSR) test. Unsupervised hierarchical clustering was used to identify methylation subtypes in CRC.

RESULTS

In this study we characterized the DNA methylation profiles of 94 CRC tissues and their matched normal counterparts. Consistent with previous studies, unsupervized hierarchical clustering of genome-wide methylation data identified three subtypes within the tumour samples, designated CIMP-H, CIMP-L and CIMP-N, that showed high, low and very low methylation levels, respectively. Differential methylation between normal and tumour samples was analysed at the individual CpG level, and at the gene level. The distribution of hypermethylation in CIMP-N tumours showed high inter-tumour variability and appeared to be highly stochastic in nature, whereas CIMP-H tumours exhibited consistent hypermethylation at a subset of genes, in addition to a highly variable background of hypermethylated genes. EYA4, TFPI2 and TLX1 were hypermethylated in more than 90% of all tumours examined. One-hundred thirty-two genes were hypermethylated in 100% of CIMP-H tumours studied and these were highly enriched for functions relating to skeletal system development (Bonferroni adjusted p value =2.88E-15), segment specification (adjusted p value =9.62E-11), embryonic development (adjusted p value =1.52E-04), mesoderm development (adjusted p value =1.14E-20), and ectoderm development (adjusted p value =7.94E-16).

CONCLUSIONS

Our genome-wide characterization of DNA methylation in colorectal cancer has identified 132 genes hypermethylated in 100% of CIMP-H samples. Three genes, EYA4, TLX1 and TFPI2 are hypermethylated in >90% of all tumour samples, regardless of CIMP subtype.

Nadolol reduces insulin sensitivity in liver cirrhosis: a randomized double-blind crossover trial

BACKGROUND

Liver cirrhosis is frequently complicated by portal hypertension leading to increased mortality from variceal bleeding and hepatic decompensation. Noncardioselective β-blockers not only reduce portal hypertension and prevent variceal bleeding in cirrhosis but also impair glucose tolerance and insulin sensitivity in other settings. This study aimed to determine whether nonselective β-blockade with nadolol impairs glucose metabolism in liver cirrhosis.

METHODS

A randomized, double-blind, placebo-controlled crossover trial of nadolol in cirrhotic patients examined insulin sensitivity, disposition index, and glucose tolerance. Stable cirrhotic patients of mixed etiology underwent an intravenous glucose tolerance test and hyperinsulinemic-euglycemic clamp for the measurement of insulin secretion and insulin sensitivity (n = 16) and a 75-g oral glucose tolerance test (n = 17). These measurements were conducted twice (after 3 months of treatment with nadolol or placebo and, after a 1-month washout period, after 3 months on the alternative treatment). Total body fat and plasma catecholamines were measured at the end of each 3-month treatment.

RESULTS

Compared with placebo, nadolol treatment reduced insulin sensitivity (79.7 ± 10.1 vs 99.6 ± 10.3 μL/kg fat-free mass·min^-1 ·(mU/L)^-1 , P = .005). Insulin secretion was unchanged (P = .24), yielding a lower disposition index with nadolol (6083 ± 2007 vs 8692 ± 2036, P = .050). There was no change in total body fat or plasma catecholamines. A 2-hour plasma glucose concentration from the oral glucose tolerance test was higher on nadolol than placebo (10.8 ± 0.9 vs 9.9 ± 0.9 mmol/L, P = .035).

CONCLUSIONS

Nadolol significantly worsened insulin sensitivity, glycemia, and disposition index in patients with liver cirrhosis. These findings may have significant clinical implications because cirrhosis is already associated with an increased prevalence of diabetes.

Network meta-analysis of the effect of preoperative carbohydrate loading on recovery after elective surgery

BACKGROUND

Three meta-analyses have summarized the effects of preoperative carbohydrate administration on postoperative outcomes in adult patients undergoing elective surgery. However, these studies could not account for the different doses of carbohydrate administered and the different controls used. Multiple-treatments meta-analysis allows robust synthesis of all available evidence in these situations.

METHODS

Article databases were searched systematically for RCTs comparing preoperative carbohydrate administration with water, a placebo drink, or fasting. A four-treatment multiple-treatments meta-analysis was performed comparing two carbohydrate dose groups (low, 10-44 g; high, 45 g or more) with two control groups (fasting; water or placebo). Primary outcomes were length of hospital stay and postoperative complication rate. Secondary outcomes included postoperative insulin resistance, vomiting and fatigue.

RESULTS

Some 43 trials involving 3110 participants were included. Compared with fasting, preoperative low-dose and high-dose carbohydrate administration decreased postoperative length of stay by 0·4 (95 per cent c.i. 0·03 to 0·7) and 0·2 (0·04 to 0·4) days respectively. There was no significant decrease in length of stay compared with water or placebo. There was no statistically significant difference in the postoperative complication rate, or in most of the secondary outcomes, between carbohydrate and control groups.

CONCLUSION

Carbohydrate loading before elective surgery conferred a small reduction in length of postoperative hospital stay compared with fasting, and no benefit in comparison with water or placebo.

Functional impairment of infiltrating T cells in human colorectal cancer

T cells play a crucial role in preventing the growth and spread of colorectal cancer (CRC). However, immunotherapies against CRC have only shown limited success, which may be due to lack of understanding about the effect of the local tumor microenvironment (TME) on T cell function. The goal of this study was to determine whether T cells in tumor tissue were functionally impaired compared to T cells in non-tumor bowel (NTB) tissue from the same patients. We showed that T cell populations are affected differently by the TME. In the tumor, T cells produced more IL-17 and less IL-2 per cell than their counterparts from NTB tissue. T cells from tumor tissue also had impaired proliferative ability compared to T cells in NTB tissue. This impairment was not related to the frequency of IL-2 producing T cells or regulatory T cells, but T cells from the TME had a higher co-expression of inhibitory receptors than T cells from NTB. Overall, our data indicate that T cells in tumor tissue are functionally altered by the CRC TME, which is likely due to cell intrinsic factors. The TME is therefore an important consideration in predicting the effect of immune modulatory therapies.

Clinico-pathological factors influencing lymph node yield in colorectal cancer and impact on survival: analysis of New Zealand Cancer Registry data

BACKGROUND

Lymph node yield (LNY) and lymph node ratio (LNR) are recognized as independent prognostic factors in colorectal cancer (CRC).

OBJECTIVES

To examine the relationship between LNY and other clinico-pathological variables, and the prognostic value of LNY and LNR on patient survival in CRC.

METHODS

The clinico-pathological and survival data for patients diagnosed from January 2000 to July 2012 were retrieved from the New Zealand Cancer Registry. Multiple linear regression was used to identify clinico-pathological factors influencing LNY, and Cox regression was used to determine the association between LNY and LNR and patient survival.

RESULTS

14,646 patients were included in the study (mean age 70.3 years, 50.1% male). Mean LNY was 17.4. Younger age, right-sided disease, higher T stage, female sex and no neoadjuvant radiotherapy (rectal cancer) were all associated with higher LNY (P ≤ 0.001). Overall survival in Stage I-III disease increased with higher LNY (for LNY ≥ 12, HR = 0.67, 95% CI 0.64-0.72; P < 0.001). Survival in Stage III-IV disease was inversely related to LNR (HR = 0.56, 95% CI 0.51-0.62; P < 0.001).

CONCLUSION

LNY is influenced by patient age, site of disease and T stage. LNY (Stage I-II) and LNR (Stage III-IV) have independent prognostic value in CRC.

Perioperative immunonutrition in patients undergoing liver transplantation: a randomized double-blind trial

Preliminary work suggested that perioperative immunonutrition (IMN) enriched in n-3 fatty acids, arginine, and nucleotides may improve preoperative nutritional status, enhance postoperative recovery, and reduce postoperative infectious complications in patients undergoing liver transplantation (LT). The current study examined these outcomes in a double-blind, randomized, controlled trial. Patients wait-listed for LT (n = 120) were randomized to either supplemental (0.6 L/d) oral IMN or an isocaloric control (CON). Enteral IMN or CON was resumed postoperatively and continued for at least 5 days. The change in total body protein (TBP) measured by neutron activation from study entry until immediately prior to LT was the primary endpoint and TBP measurements were repeated 10, 30, 90, 180, and 360 days after LT. Infectious complications were recorded for the first 30 postoperative days. Nineteen patients died or were delisted prior to LT. Fifty-two IMN and 49 CON patients received supplemental nutrition for a median (range) 56 (0-480) and 65 (0-348) days, respectively. Preoperative changes in TBP were not significant (IMN: 0.06 ± 0.15 [SEM]; CON: 0.12 ± 0.10 kg). Compared to baseline, a 0.7 ± 0.2 kg loss of TBP was seen in both groups at 30 days after LT (P < 0.0001) and, at 360 days, TBP had not increased significantly (IMN: 0.08 ± 0.19 kg; CON: 0.26 ± 0.23 kg). Infectious complications occurred in 31 (60%) IMN and 28 (57%) CON patients (P = 0.84). The median (range) postoperative hospital stay was 10 (5-105) days for IMN and 10 (6-27) days for CON patients (P = 0.68).

CONCLUSION

In patients undergoing LT, perioperative IMN did not provide significant benefits in terms of preoperative nutritional status or postoperative outcome.

Influence of age and site of disease on lymph node yield in colorectal cancer

AIM

Colorectal cancer (CRC) is the second-leading cause of cancer death in New Zealand. Lymph node yield (LNY) is an independent prognostic factor in CRC and 12 or more lymph nodes in the resected specimen is the current recommended standard, regardless of age or site of disease. The aim of this study was to examine the effect of age and site of the disease on LNY.

METHOD

Patients undergoing elective surgery for CRC at Dunedin Hospital between 1995 and 2012, who enrolled in studies involving prospective data and tissue collection, were included in the current study. The relationship between LNY and demographic and pathological variables including age, sex, tumour location and stage were investigated.

RESULTS

824 patients were included (mean age 70.5 years, 51% female). The mean (SD) LNY was 17.9 (10.1).There was a weak but significant negative correlation between age and LNY (r=-0.08; p=0.024) that was more evident in patients with right-sided tumours (r=0.18; p=0.001). Right-sided tumours also had a higher LNY (mean 20.5) than left colon (mean 16.8) and rectal cancer (mean 14.6) (p<0.001). Overall the mean LNY reduced by 1 for every 7 years advancement in age.

CONCLUSION

LNY is higher in right-sided colon cancer and reduces with age. Further research should consider whether the recommended standard for LNY in the specimen should take account of age and tumour location.

Does senescence affect lymph node number and morphology? A systematic review

BACKGROUND

Immunosenescence may contribute to an observed increase in infections and specific cancers in the elderly. Lymph nodes play a key role in the body's immune system. A systematic review was undertaken to investigate the effects of senescence on lymph node number and morphology.

METHODS

Electronic databases Ovid MEDLINE, Embase and Google Scholar were searched for relevant articles examining normal lymph node number and morphology with senescence. Data on lymph node number, gross anatomy and histo-architecture were collated and analysed.

RESULTS

A total of 20 articles (15 human and 5 animal studies) were eligible for inclusion; many were limited by poorly standardized methods and relatively small sample sizes. However, there is evidence to suggest both a decrease in lymph node number and histological lymph node degeneration with senescence, at least in some lymph node basins. Degenerative changes include loss of lymphoid tissue from both the cortex and the medulla of lymph nodes, a reduction in the number and size of germinal centres, and changes such as hyalinization, fibrosis, fat deposition, a decrease in high endothelial venules and 'transparency'.

CONCLUSION

In this first systematic review to examine changes in lymph nodes with senescence, evidence was accrued to suggest a decline in lymph node number and morphological degeneration in older age groups. These changes might adversely affect immune function and the prognosis of infections and selected cancers in the elderly. Further research is required to confirm these morphological changes and to explore their potential immunological and functional effects.

Oral β-blockade in relation to energy expenditure in clinically stable patients with liver cirrhosis: a double-blind randomized cross-over trial

Elevated resting energy expenditure (REE) is seen in liver cirrhosis and is associated with reduced transplant-free survival. Non-selective β-blockers reduce REE in acute hypermetabolic conditions. We examined whether non-selective β-blockers reduce REE in patients with stable liver cirrhosis. Twenty-two stable cirrhotic patients (Child-Pugh grading: 19A, 2B, 1C) were randomized to 3-month treatment with nadolol (titrated to decrease resting pulse rate by 20%) or placebo and after a 1-month washout period crossed to the alternative treatment for a further 3 months. REE was measured by indirect calorimetry and total body protein by neutron activation analysis at the beginning and end of each 3-month period of treatment. A predicted REE was calculated for each patient based on total body protein. A measured to predicted REE ratio >1.22 indicated significantly elevated REE. The primary outcome was REE at the end of 3-month treatment with nadolol compared with placebo. Elevated REE was seen in one patient at study entry. After 3 months on placebo REE was 1506±40 (SEM) kcal/d and on nadolol, 1476±40 kcal/d, a mean reduction of 31±16 kcal/d (P=.076). Total body protein changes were not significant. Nadolol was well tolerated with no increase in the rate of adverse events. In stable cirrhotic patients, nadolol was not associated with reduction in REE. A larger, longer-term study with different eligibility criteria is required to investigate whether this treatment offers benefits additional to its use for prevention of variceal hemorrhage.

Biliary complications following orthotopic liver transplantation: a 10-year audit

BACKGROUND

Biliary complications following liver transplantation result in major morbidity. We undertook a 10-year audit of the incidence, management and outcomes of post-transplant biliary complications at the New Zealand Liver Transplant Unit.

METHODS

Prospectively collected data on 348 consecutive liver transplants performed between February 1998 and October 2008 were reviewed. The minimum follow-up was 6 months.

RESULTS

A total of 309 adult and 39 paediatric transplants were performed over the study period. Of these, 296 (85%) were whole liver grafts and 52 (15%) were partial liver grafts (24 split-liver, eight reduced-size and 20 live-donor grafts). There were 80 biliary complications, which included 63 (18%) strictures and 17 (5%) bile leaks. Partial graft, a paediatric recipient and a Roux-en-Y biliary anastomosis were independent predictors of biliary strictures. Twenty-five (40%) strictures were successfully managed non-operatively and 38 (60%) required surgery (31 biliary reconstructions, three segmental resections and four retransplants). Seven (41%) bile leaks required surgical revision and 10 (59%) were managed non-operatively. There was no mortality related directly to biliary complications.

CONCLUSIONS

Biliary complications affected one in five transplant recipients. Paediatric status, partial graft and Roux-en-Y anastomosis were independently associated with the occurrence of biliary strictures. Over half of the affected patients required surgical revision, but no mortality resulted from biliary complications.

Reverse portal flow after liver transplantation--ominous or acceptable?

Reversal of portal flow or hepatofugal flow after liver transplantation is a rare complication after liver transplantation. The available reports in the literature suggest that it is an ominous condition that requires immediate operative intervention, failing which prognosis would be grim. We report two children from two different centers who developed hepatofugal flow in the immediate post-operative period after liver transplantation. The possible etiologies in these patients were acute rejection in one and absence of an MHV causing inadequate hepatic venous outflow in the other. Both patients were treated non-operatively with steroids and immunosuppression. Spontaneous reversal to a normal hepatopetal flow occurred in both and the patients continue to be well six months after the transplant. Our experience contradicts the viewpoint that hepatofugal flow equates to mortality in the absence of surgical intervention. It remains to be defined as to which patients with hepatofugal flow will benefit from surgical intervention.

Randomized controlled trial of preoperative oral carbohydrate treatment in major abdominal surgery

Background

Major surgery is associated with postoperative insulin resistance which is attenuated by preoperative carbohydrate (CHO) treatment. The effect of this treatment on clinical outcome after major abdominal surgery has not been assessed in a double-blind randomized trial.

Methods

Patients undergoing elective colorectal surgery or liver resection were randomized to oral CHO or placebo drinks to be taken on the evening before surgery and 2 h before induction of anaesthesia. Primary outcomes were postoperative length of hospital stay and fatigue measured by visual analogue scale.

Results

Sixty-nine and 73 patients were evaluated in the CHO and placebo groups respectively. The groups were well matched with respect to surgical procedure, epidural analgesia, laparoscopic procedures, fasting period before induction and duration of surgery. Postoperative changes in fatigue score from baseline did not differ between the groups. Median (range) hospital stay was 7 (2–35) days in the CHO group and 8 (2–92) days in the placebo group (P = 0·344). For patients not receiving epidural blockade or laparoscopic surgery (20 CHO, 19 placebo), values were 7 (3–11) and 9 (2–48) days respectively (P = 0·054).

Conclusion

Preoperative CHO treatment did not improve postoperative fatigue or length of hospital stay after major abdominal surgery. A benefit is not ruled out when epidural blockade or laparoscopic procedures are not used. Registration number: ACTRN012605000456651 (http://www.anzctr.org.au).

Systematic review of tumour number and outcome after radical treatment of colorectal liver metastases

Background

Resection of colorectal liver metastases (CLMs) is potentially curative but the effect of tumour number on prognosis is uncertain. This study compared the prognosis after resection and/or ablation of between one and three, or four or more CLMs.

Methods

A systematic literature review from January 2000 to June 2008 was performed. Study selection and data extraction were standardized, and analysis included assessment of methodological quality, heterogeneity and bias. Main outcomes were 3- and 5-year survival. A meta-analysis comparing radical treatment in the two groups was performed using the hazard ratio for overall survival.

Results

Of 1307 studies screened, 46 (9934 patients) were included in the analysis. Methodological quality was variable, and there was significant heterogeneity and reporting bias. The overall 5-year survival rate after radical treatment ranged from 7 to 58 per cent. Pooled hazard ratio for overall survival was 1·67 (95 per cent confidence interval 1·43 to 1·95; P &lt; 0·001). Median reported 5-year survival for patients with four or more CLMs was 17·1 per cent.

Conclusion

Radical treatment of more than three CLMs results in poorer overall survival. Nevertheless, 5-year survival is achievable and the number of lesions should not, of itself, be used to exclude patients from surgery.

Reduced expression of a gene proliferation signature is associated with enhanced malignancy in colon cancer

The association between cell proliferation and the malignant potential of colon cancer is not well understood. Here, we evaluated this association using a colon-specific gene proliferation signature (GPS). The GPS was derived by combining gene expression data obtained from the analysis of a cancer cell line model and a published colon crypt profile. The GPS was overexpressed in both actively cycling cells in vitro and the proliferate compartment of colon crypts. K-means clustering was used to independantly stratify two cohorts of colon tumours into two groups with high and low GPS expression. Notably, we observed a significant association between reduced GPS expression and an increased likelihood of recurrence (P<0.05), leading to shorter disease-free survival in both cohorts. This finding was not a result of methodological bias as we verified the well-established association between breast cancer malignancy and increased proliferation, by applying our GPS to public breast cancer data. In this study, we show that reduced proliferation is a biological feature characterizing the majority of aggressive colon cancers. This contrasts with many other carcinomas such as breast cancer. Investigating the reasons underlying this unusual observation may provide important insight into the biology of colon cancer progression and putative novel therapy options.

Poorer survival in patients whose explanted hepatocellular carcinoma (HCC) exceeds Milan or UCSF Criteria. An analysis of liver transplantation in HCC in Australia and New Zealand

BACKGROUND

Milan and University of California San Francisco (UCSF) Criteria have been used for selection of patients with hepatocellular carcinoma (HCC) for liver transplantation (LTx). The aims of this study were to analyse the results of LTx for HCC in Australia and New Zealand with emphasis on the effects of discordance between pre-LTx radiological and post-LTx pathological staging.

METHODS

A total of 186 LTx for HCC carried out between July 1985 and August 2003 were included. Patients were categorized according to the Milan and UCSF Criteria.

RESULTS

The median follow-up was 6.55 years (range 2.96-20.93 years). Pre-LTx factors associated with better survival include tumour size < or = 5 cm, number of tumours < or = 3, staging within Milan and UCSF Criteria and more recent transplantation (1996-2003). In all, 14 patients had a pre-LTx stage outside the Milan but within the UCSF Criteria. One- and 5-year patient survival rates were, respectively, 88% and 74% within the Milan Criteria, and 87% and 73% within the UCSF Criteria. Vascular invasion, capsular invasion, lymph node invasion and pathological stage outside UCSF Criteria were associated with poor outcome. Of patients within the Milan and UCSF Criteria pre-LTx, 24% and 18%, respectively, were outside the same criteria post-LTx. These patients had poorer survival rates.

CONCLUSIONS

The use of the UCSF Criteria in this cohort increased the number of patients eligible for LTx without compromising 5-year survival rates. Patients whose explant tumours were outside the Milan or UCSF Criteria had poorer outcomes compared with those whose explants remained within these criteria.

Nocturnal nutritional supplementation improves total body protein status of patients with liver cirrhosis: a randomized 12-month trial

Patients with liver cirrhosis exhibit early onset of gluconeogenesis after short-term fasting. This accelerated metabolic reaction to starvation may underlie their increased protein requirements and muscle depletion. A randomized controlled trial was conducted to test the hypothesis that provision of a late-evening nutritional supplement over a 12-month period would improve body protein stores in patients with cirrhosis. A total of 103 patients (68 male, 35 female; median age 51, range 28-74; Child-Pugh grading: 52A, 31B, 20C) were randomized to receive either daytime (between 0900 and 1900 hours) or nighttime (between 2100 and 0700 hours) supplementary nutrition (710 kcal/day). Primary etiology of liver disease was chronic viral hepatitis (67), alcohol (15), cholestatic (6), and other (15). Total body protein (TBP) was measured by neutron activation analysis at baseline, 3, 6, and 12 months. Total daily energy and protein intakes were assessed at baseline and at 3 months by comprehensive dietary recall. As a percentage of values predicted when well, TBP at baseline was similar for the daytime (85 +/- 2[standard error of the mean]%) and nighttime (84 +/- 2%) groups. For the nighttime group, significant increases in TBP were measured at 3 (0.38 +/- 0.10 kg, P = 0.0004), 6 (0.48 +/- 0.13 kg, P = 0.0007), and 12 months (0.53 +/- 0.17 kg, P = 0.003) compared to baseline. For the daytime group, no significant changes in TBP were seen. Daily energy and protein intakes at 3 months were higher than at baseline in both groups (P < 0.0001), and these changes did not differ between the groups.

CONCLUSION

Provision of a nighttime feed to patients with cirrhosis results in body protein accretion equivalent to about 2 kg of lean tissue sustained over 12 months. This improved nutritional status may have important implications for the clinical course of these patients.

Serum sodium and hydration status predict transplant-free survival independent of MELD score in patients with cirrhosis

BACKGROUND AND AIM

Serum sodium may have prognostic value in addition to the model for end-stage liver disease (MELD) score for prediction of early mortality in patients listed for liver transplant. In patients with cirrhosis, over-hydration is a common feature but its prognostic value has not been evaluated. This study examines the independent prognostic significance of MELD, serum sodium and hydration status on long-term survival in patients with cirrhosis.

METHODS

Serum sodium and hydration (total body water as a percentage of fat-free mass) were measured in 227 consecutive cirrhotic patients (146 male, 81 female; median age 49 years, range 19-73 years; median MELD score 13, range 6-36). Patients with hepatocellular carcinoma or listed for liver transplantation at the time of initial assessment were excluded. A competing risks Cox proportional hazards analysis was performed to evaluate the influence of MELD, sodium and hydration on risk of death or transplant.

RESULTS

Median follow-up was 52 (range 4-93) months. Serum sodium and hydration were each associated with reduction in time to death or transplant on univariate analysis (sodium: hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.87-0.94, P < 0.0001; hydration: HR 1.20, 95% CI 1.10-1.30, P < 0.0001). On multivariate analysis, MELD, serum sodium and hydration were independently predictive of death or transplant (MELD: HR 1.12, 95% CI 1.06-1.19, P < 0.0001; sodium: HR 0.93, 95% CI 0.87-0.99, P = 0.04; hydration: HR 1.17, 95% CI 1.02-1.33, P = 0.02).

CONCLUSIONS

In non-waitlisted patients with cirrhosis, serum sodium is predictive of transplant or death independent of MELD score.

Genome wide expression profiling identifies genes associated with colorectal liver metastasis

Tumour cells have to undergo gene expression changes in order to metastasise and adapt to a new site. We investigated these changes in liver metastases of colorectal cancer by using genome-wide microarray analysis to profile the expression of 48 primary tumours and 28 liver metastases. Statistical analysis of these expression profiles using the significance analysis of microarrays (SAM) method identified 778 genes differentially expressed between primary tumours and metastases. Gene ontology analysis revealed that genes associated with tissue remodelling and immune response were upregulated in metastases relative to primary tumours, whereas genes associated with proliferation and oxidative phosphorylation were downregulated. Quantitative real-time PCR confirmed the differential expression of selected genes, osteopontin, versican, ADAM17, CKS2, PRDX1, CXCR4, CXCL12, and LCN2. The upregulation of genes associated with tissue remodelling and immune response are likely to be involved in metastatic invasion and colonisation of the new site because these genes can promote tumour progression. However, downregulation of genes associated with proliferation suggests that proliferation in metastases was reduced relative to primary tumours.

Liver resection for hepatocellular carcinoma in a hepatitis B endemic area

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver. Treatment options include liver resection, tumor ablation, and liver transplantation.

METHODS

We report the results of all patients undergoing partial hepatectomy for HCC with curative intent from a center where all major treatment modalities were available.

RESULTS

A series of 53 patients were identified, of whom 72% had underlying liver disease, mostly chronic hepatitis B infection. Altogether, 57% of patients underwent major resections, of whom 43% had histologically proven cirrhosis. Postoperative morbidity and mortality occurred in 41.5% and 7.5%, respectively. After a median follow-up of 34 months, the survival probabilities at 1, 3, and 5 years were 74.1%, 54.1%, and 42.6%, respectively. A total of 47% developed recurrent disease over the study period with a median disease-free survival of 13.8 months. The probabilities of recurrence at 1, 3, and 5 years were 35.2%, 49.4%, and 55.9%, respectively. Among those who developed recurrence, 76% died, with a median time to death from the time the recurrence was diagnosed of 7.8 months. There was a good association between the CLIP score and survival following liver resection. Multivariate analysis showed that only tumor recurrence and the presence of cirrhosis was a significant determinant of the risk of tumor-related death.

CONCLUSION

These findings confirm that with careful patient selection liver resection for HCC can achieve good long-term patient survival and acceptable risks.

Body composition, muscle function, and energy expenditure in patients with liver cirrhosis: a comprehensive study

BACKGROUND

Data describing the nutritional status of patients with liver cirrhosis of diverse origin, as assessed by direct body-composition methods, are limited.

OBJECTIVE

We sought to provide a comprehensive assessment of nutritional status and metabolic activity in patients with liver cirrhosis by using the most accurate direct methods available.

DESIGN

Two hundred sixty-eight patients (179 M, 89 F; x +/- SEM age: 50.1 +/- 0.6 y) with liver cirrhosis underwent measurements of total body protein by neutron activation analysis, of total body fat and bone mineral by dual-energy X-ray absorptiometry, of resting energy expenditure by indirect calorimetry, of grip strength by dynamometry, and of respiratory muscle strength by using a pressure transducer. Dietary intakes of energy and protein were assessed and indexed to resting energy expenditure and energy intake, respectively.

RESULTS

Significant protein depletion, seen in 51% of patients, was significantly (P<0.0001) more prevalent in men (63%) than in women (28%). This sex difference occurred irrespective of disease severity or origin. The prevalence of protein depletion increased significantly (P<0.0001) with disease severity. Protein depletion was associated with decreased muscle function but not with lower energy and protein intake. Energy intake was significantly (P=0.002) higher in men than in women, whereas protein intakes did not differ significantly (P=0.12). Hypermetabolism, seen in 15% of patients, was not associated with sex, origin or severity of disease, protein depletion, ascites, or presence of tumor.

CONCLUSIONS

Poor nutritional status with protein depletion and reduced muscle function was a common finding, particularly in men, and was not related to the presence of hypermetabolism or reduced energy and protein intakes. The greater conservation of protein stores in women than in men warrants further investigation.

Multiple gene expression classifiers from different array platforms predict poor prognosis of colorectal cancer

PURPOSE

This study aimed to develop gene classifiers to predict colorectal cancer recurrence. We investigated whether gene classifiers derived from two tumor series using different array platforms could be independently validated by application to the alternate series of patients.

EXPERIMENTAL DESIGN

Colorectal tumors from New Zealand (n = 149) and Germany (n = 55) patients had a minimum follow-up of 5 years. RNA was profiled using oligonucleotide printed microarrays (New Zealand samples) and Affymetrix arrays (German samples). Classifiers based on clinical data, gene expression data, and a combination of the two were produced and used to predict recurrence. The use of gene expression information was found to improve the predictive ability in both data sets. The New Zealand and German gene classifiers were cross-validated on the German and New Zealand data sets, respectively, to validate their predictive power. Survival analyses were done to evaluate the ability of the classifiers to predict patient survival.

RESULTS

The prediction rates for the New Zealand and German gene-based classifiers were 77% and 84%, respectively. Despite significant differences in study design and technologies used, both classifiers retained prognostic power when applied to the alternate series of patients. Survival analyses showed that both classifiers gave a better stratification of patients than the traditional clinical staging. One classifier contained genes associated with cancer progression, whereas the other had a large immune response gene cluster concordant with the role of a host immune response in modulating colorectal cancer outcome.

CONCLUSIONS

The successful reciprocal validation of gene-based classifiers on different patient cohorts and technology platforms supports the power of microarray technology for individualized outcome prediction of colorectal cancer patients. Furthermore, many of the genes identified have known biological functions congruent with the predicted outcomes.

Hypermetabolism predicts reduced transplant-free survival independent of MELD and Child-Pugh scores in liver cirrhosis

OBJECTIVE

A subgroup of cirrhotic patients develop hypermetabolism, possibly mediated by increased sympathetic nervous system activity and increased cardiac output. The effect of hypermetabolism on prognosis in patients with cirrhosis has not been elucidated.

METHODS

Resting energy expenditure (REE) was measured using indirect calorimetry in 256 cirrhotic patients with different etiologies and disease severity (165 men, 91 women; median age 49 y, age range 16-73 y; median model for end-stage liver disease [MELD] score 13, range 6-36; median Child-Pugh score 8, range 5-15). Measured and predicted values were compared using equations based on fat-free mass, total body protein (measured by neutron activation analysis), and the Harris-Benedict equations. Competing-risks Cox's proportional hazards analysis was performed to evaluate the influence of hypermetabolism and MELD or Child-Pugh scores on risk of death or liver transplantation.

RESULTS

Median follow-up was 49 mo (range 1-90 mo). Hypermetabolic patients had decreased transplant-free survival compared with non-hypermetabolic patients (9.7 versus 31.8 mo, P = 0.05). Increased REE, even within the normal range, was also associated with worse transplant-free survival (P = 0.001). Hypermetabolism was predictive of transplant-free survival independent of MELD and Child-Pugh scores (hazard ratio 1.19, 95% confidence interval 1.08-1.32, P = 0.0008; hazard ratio 1.13, 95% confidence interval 1.10-1.16, P < 0.0001; hazard ratio 1.38, 95% confidence interval 1.29-1.48, P < 0.0001; respectively). Patients on beta-blockers were more likely to be normometabolic (P = 0.035).

CONCLUSION

We found an inverse relation between REE and transplant-free survival in a large heterogeneous group of cirrhotic patients.

Is routine placement of surgical drains necessary after elective hepatectomy? Results from a single institution

Routine drainage is no longer used after many major abdominal procedures. However, the role of routine surgical drainage after hepatic resection is unclear. Of the two randomized trials published, one concluded drainage is unnecessary after hepatectomy, and another concluded it could be used after major resections only. Between January 1999 and December 2003, 211 elective hepatic resections were performed by two surgeons at Auckland Hospital. Drains were used routinely by one surgeon (n = 126), while another routinely did not drain (n = 85). Patients undergoing a biliary reconstruction were not included in this analysis. Patient and clinical data were recorded prospectively, and no outcome analyses were performed until 2004. The demographic features were similar between the drained and non-drained groups. There were no differences in length of hospital stay (no drain, 7 +/- 0.8 days; drain, 7 +/- 0.9 days: P = not significant [NS]), in mortality (no drain, 1.2%; drain, 1.6%: P = NS), biliary fistula (no drain, zero cases; drain, two cases: P = NS), or overall complication rate (no drain, 50.5%; drain, 54.7%: P = NS). Both groups had similar rates of postoperative collection (no drain, four patients [5%]; drain, five patients [4%]: P = NS), and there was no difference in the use of percutaneous drainage of collections between the groups (no drain, four patients [5%]; drain, two patients [2%]: P = NS). Multivariate analysis showed that intraoperative blood loss of 2000 ml or greater (relative risk [RR], 1.57; 95% confidence interval [CI], 1.39-1.75; P < 0.01), number of segments resected (RR, 1.4; 95% CI, 1.21-1.89; P < 0.01), and presence of steatosis/fibrosis or cirrhosis (RR, 1.6; 95% CI, 1.01-2.1; P < 0.05) to be predictive of postoperative complications. The presence of a surgical drain was not predictive of complications. Routine surgical drainage after elective hepatectomy is not necessary.

Pre- and postoperative immunonutrition in patients undergoing liver transplantation: a pilot study of safety and efficacy

BACKGROUND & AIMS

Malnutrition is common in patients with end-stage liver disease and is a risk factor for post-transplant morbidity. The goal of this study was to assess the safety of an immune-enhancing diet in patients undergoing liver transplantation and to investigate its effects on nutritional status.

METHODS

Fifteen consecutive patients received oral Impact (0.6l/d) for a median 54 (range 10-168)d pre-transplant and enteral Impact was started early after transplant. Total body protein was measured prior to commencing supplemental Impact, immediately prior to transplant and 10, 15, 30, 90, and 180 days post-transplant. The results were compared with those from 17 patients who received standard nutritional intervention.

RESULTS

All study patients tolerated Impact pre- and postoperatively and there were no safety concerns. Over the preoperative period total body protein increased significantly (P = 0.017). In 7 patients followed for 6 months post-transplant, a significant (P = 0.026) loss of body protein occurred over the first 15 postoperative days which was regained by 6 months. In the patients who did not receive Impact, body protein did not change preoperatively and the loss after surgery was not regained. Infectious complications occurred in 5/15 (33%) Impact patients and 12/17 (71%) non-Impact patients (P = 0.074).

CONCLUSIONS

In patients with end-stage liver disease, our results suggest the possibility that Impact may have a role in improving preoperative nutritional status, hastening recovery after transplant, and reducing postoperative infectious complications. These potential benefits need to be confirmed in a randomised controlled trial.

Focal nodular hyperplasia: what are the indications for resection?

Focal nodular hyperplasia (FNH) is a benign condition of the liver that is often discovered incidentally on radiological investigation. FNH has no malignant potential, is rarely symptomatic and surgical intervention is almost never required. However, eight patients with a diagnosis of FNH associated with upper abdominal pain or rapid growth were referred for surgery. All patients had been extensively investigated for other causes of pain and had been observed for between 1 and 7 years prior to surgical referral. The FNH lesions were between 1 cm and 8 cm in diameter. One FNH lesion 7.5 cm in diameter lay in segment VII/VIII and was related to the right and middle hepatic veins. All patients were resected with immediate and lasting control of their symptoms. Based on this experience FNH should be managed in a manner similar to haemangiomas with most lesions being safe to observe. However, it should be recognized that symptomatic FNH does occur, as well as FNH behaving in an unusual fashion such as rapid growth. Both of these findings are indications for resection.

Laparoscopic staging of upper gastrointestinal malignancy

BACKGROUND

Laparoscopic staging (LS) of upper gastrointestinal malignancy has decreased the number of non-curative laparotomies. However, as radiological techniques have improved the value of this invasive staging technique has decreased, with some units either being more selective or abandoning it altogether for certain tumour types. The aim of the present study is to prospectively evaluate the additional utility of LS of upper gastrointestinal malignancy after radiological staging with modern techniques.

METHODS

One hundred and six consecutive patients assessed as having potentially curable upper gastrointestinal malignancy after radiological staging underwent LS between April 1999 and June 2001. Laparoscopic findings, outcome at laparotomy and complications were prospectively recorded.

RESULTS

Laparoscopic staging detected incurable disease in 28 of the 106 patients (26%). The negative likelihood ratio was 0.36 (95% CI 0.24-0.53). Twenty-seven patients were considered incurable because of findings at laparoscopy and one on the findings of laparoscopic ultrasound. Ten patients underwent open palliative procedures and seven had non-therapeutic laparotomies giving a non-curative laparotomy rate of 16%. LS was most useful for primary liver and biliary tract tumours and was least useful for colorectal liver metastases. The most frequent findings denoting incurability were the presence of liver disease (12 cases) and peritoneal metastases (nine cases). Complications occurred in three patients with one death being attributable in part to the laparoscopy.

CONCLUSIONS

Laparoscopy was useful in decreasing the number of non-therapeutic laparotomies, but laparoscopic ultrasound gave little additional benefit. The utility of LS was dependent on tumour type and in particular was of marginal benefit for colorectal liver metastases. LS remains a useful staging tool but should be applied selectively.

Intragraft gene and protein expression in rat liver allografts treated with costimulatory blockade alone or in combination with CyA

BACKGROUND

Costimulatory blockade has been shown to prevent acute rejection (AR) and promote long-term graft survival in a number of animal models including nonhuman primates. The effect of concomitant administration of conventional immunosuppressives on long-term liver allograft survival and intragraft expression of immune mediators has not previously been examined.

MATERIALS AND METHODS

A high-responding Dark Agouti to Lewis orthotopic liver transplant (LEW OLT) model was used to compare anti-CD154 alone, or in combination with cyclosporin (CyA) on allograft survival. Donor-specific reactivity was assessed by mixed lymphocyte reaction (MLR) and allogeneic skin grafts. Surviving rats were euthanized on day 150 and intragraft gene (CD80, 86, 152, 154, IFN-gamma, IL-2, IL-6, IL-10, IL-13, TNF-alpha, TGF-beta, IL-7, Fas-ligand, Granzyme B, bax, and bcl(2)) and protein (CD4, CD8, ED1, CD154, CD80, CD86) expression was measured.

RESULTS

Untreated control recipients had a median survival time of 5 days. Recipients treated with anti-CD154 survived to beyond 150 days with no evidence of AR. Concomitant administration of CyA did not alter the long-term survival. There was no difference in the serum aspartate aminotransferase between treatment groups or a change over time. All treated recipients showed a reduction in donor-specific MLR at day 40 and 60 but had persistence of donor reactivity to skin grafts at day 100. Histologically, liver architecture was well preserved despite the presence of a nondestructive mononuclear cell infiltrate. Analysis of intragraft gene expression revealed an inverse relationship between the duration of anti-CD154 therapy and the gene expression of costimulatory molecules and Th1 cytokine transcripts. The pro-apoptotic gene, bax, was increased in recipients treated with anti-CD154, but not CyA, compared with normal liver.

CONCLUSIONS

These data demonstrate that anti-CD154 therapy either alone or in combination with CyA allows for the long-term survival of liver allografts in the rat despite there being a difference in the intragraft gene and protein profile.

Analysis of intragraft gene and protein expression of the costimulatory molecules, CD80, CD86 and CD154, in orthotopic liver transplant recipients

CD40-CD154 and/or CD28-CD80/86 costimulatory blockade induces long-term allograft survival in numerous animal models. Studies examining the expression of costimulatory molecules during acute cellular rejection (ACR) have been limited to renal and cardiac allografts. The aim of this study was to describe the relationship between intragraft costimulatory molecule expression in OLT recipients and ACR. Forty-five liver biopsies were obtained at reperfusion and day 7. Gene and protein expression of CD80, CD86 and CD154 were analyzed by RT-PCR and immunohistochemistry. CD154 protein expression was present in 13 of 18 patients with a RAI score of 4, but in only two of 14 patients with a RAI score of <4. There was a strong association between the RAI score and the presence of CD80 and CD154 immunoreactivity. CD86 protein expression did not correlate with the severity of ACR. In reperfusion biopsies CD154, but not CD80 or CD86, protein expression correlated with the total ischaemic time. There was no association between expression of costimulatory molecule genes and ACR. In conclusion, we have demonstrated an association between CD154 and CD80 protein expression and ACR in orthotopic liver allografts.

Risk of dissemination with biopsy of colorectal liver metastases

PURPOSE

Liver surgeons usually recommend against biopsy of colorectal liver metastases because of the risk of local dissemination. To date, only case reports describing this problem have been published. This study is an attempt to quantify the risk of biopsy-related dissemination.

METHODS

A multicenter, retrospective review was undertaken of cases of colorectal liver metastases presenting for surgery that had undergone a preoperative biopsy.

RESULTS

Two hundred thirty-one cases of colorectal liver metastases presenting for surgery were identified. Forty-three cases had undergone a preoperative biopsy (18.6 percent). Seven patients had evidence of dissemination related to the biopsy, giving a risk of dissemination of 16 percent (95 percent confidence interval, 7-30 percent). The risk of dissemination was not related to the type of biopsy. Within the follow-up period (median, 21 months), 3 of the 7 cases with evidence of dissemination and 11 of the 35 without dissemination were alive without disease. Twenty-five percent of the 36 cases without dissemination were resected, whereas 6 of the 7 cases with dissemination were resected.

CONCLUSIONS

There is a significant risk of local dissemination with biopsy of colorectal liver metastases. In this series this was independent of the type of biopsy. There was no demonstrated effect on resectability or survival, but numbers were small, and the median follow-up was short.

Prognostic significance of occult metastases in colon cancer

PURPOSE

The purpose of this study was to determine the prognostic significance of occult lymph node metastases in colon cancer detected by cytokeratin 20 reverse transcription polymerase chain reaction.

METHODS

Two hundred patients undergoing elective colonic resections were enrolled in the study. Lymph nodes from resected specimens were dissected fresh and assessed by both reverse transcription polymerase chain reaction and histopathology. Follow-up was undertaken for up to five years, and the major end point of death was recorded. Univariate survival analysis was performed by the log-rank method and the change-in-estimate method was used to construct multivariate analysis models for the effect of cytokeratin 20 reverse transcription polymerase chain reaction lymph node status on overall survival.

RESULTS

A total of 2,317 lymph nodes from 200 patients were assessed by both histopathology and cytokeratin 20 reverse transcription polymerase chain reaction. Forty-eight of 141 (34 percent) histologically lymph node-negative patients had evidence of occult metastases by cytokeratin 20 reverse transcription polymerase chain reaction. An interim analysis was performed at a median of 42 (range, 23-75) months. Cytokeratin 20 reverse transcription polymerase chain reaction lymph node status was a highly significant predictor of overall survival (P < 0.0001) on univariate analysis. In addition, the number of reverse transcription polymerase chain reaction-positive lymph nodes was a significant predictor of survival in the histologically lymph node-negative group (P < 0.0001) on univariate analysis. On multivariate analysis cytokeratin 20 reverse transcription polymerase chain reaction lymph node status had independent prognostic significance for overall survival (P = 0.021; hazard ratio = 2.7) and the number of cytokeratin 20 reverse transcription polymerase chain reaction-positive lymph nodes was a significant predictor of overall survival in the histologically lymph node-negative group (P = 0.005; hazard ratio = 1.1-11.1).

CONCLUSION

Cytokeratin 20 reverse transcription polymerase chain reaction has potential as a clinically useful marker for staging colorectal cancer. Further follow-up is required, but if the current trends continue, a study of the effect of adjuvant therapy in patients with occult metastases detected by cytokeratin 20 reverse transcription polymerase chain reaction is indicated.

Inflammatory pseudotumor of the liver: demographics, diagnosis, and the case for nonoperative management

BACKGROUND

Inflammatory pseudotumor of the liver (IPL) is an unusual tumor-like condition that is becoming recognized as an important differential diagnosis in the patient presenting with liver masses. This report describes six cases of IPL.

STUDY DESIGN

Clinical, diagnostic, pathologic, and followup data were collected prospectively on six patients presenting to a specialist hepatobiliary unit.

RESULTS

Six patients with IPL presented over a 2-year period. Median age was 35 years (range 2 to 79 years) and five patients were men. Three patients were Polynesian (Tongan and Samoan) and one was New Zealand Maori. Five patients presented with nonspecific symptoms (fever, arthralgia, myalgia) and IPL was an incidental finding in one patient. At presentation, four patients had elevated white cell counts, and five patients had abnormal liver function tests with elevations in alkaline phosphotase and gamma-glutamyl transferase the most commonly seen. Carcinogenic embryonic antigen and alpha fetoprotein were normal in all patients, although one was a known hepatitis B carrier. In all cases of IPL, diagnosis was made on core biopsy of the liver lesions and all patients were managed nonoperatively with complete resolution of the tumors. Two patients had marked reduction in systemic symptoms (fever and pain) from a short course of oral steroids.

CONCLUSIONS

IPL appears to be a relatively common problem in Maori and Polynesians. Recognition and differentiation of this condition from malignant liver lesions are important to avoid unnecessary surgery.

The natural history of acute histologic rejection without biochemical graft dysfunction in orthotopic liver transplantation: a systematic review

Protocol biopsy results in the first few weeks after liver transplantation sometimes display histologic features of acute cellular rejection (ACR), even in the absence of significant clinical or biochemical dysfunction. At present there is no clear consensus about the need to treat such cases with adjuvant immunosuppression. This systematic review describes, from the available evidence, the natural history of untreated histologic ACR in the absence of biochemical graft dysfunction. An electronic search of the Medline, Embase, and Cochrane Library databases was performed to select studies that reported protocol liver biopsies in the early posttransplant period from 1983 to 2000. Studies that identified patients with ACR on protocol biopsy who were not treated with adjuvant immunosuppression formed the basis of the study group. Data from individual studies were extracted using standardized pro forma and pooled for descriptive analysis. The search identified 3431 studies, of which 516 were cited in full. Of these, 15 studies met all of the inclusion criteria. These 15 studies reported on 1566 patients who had protocol biopsies performed in the early posttransplant period, of which 1048 (67%) had histologic evidence of ACR. Three hundred and thirty one (32%) patients with histologic ACR on protocol biopsy had no associated biochemical graft dysfunction. Without treatment, only 14% of these patients subsequently developed biochemical graft dysfunction requiring adjuvant immunosuppression. Steroid-resistant rejection and chronic rejection both had a prevalence of 4% in patients with untreated histologic ACR and no biochemical graft dysfunction. Withholding adjuvant immunosuppression from patients with histologic ACR and no biochemical graft dysfunction seems to be safe, as long as graft function is carefully monitored. The rationale for performing protocol biopsies in the absence of biochemical graft dysfunction is questionable.

Costimulatory blockade prevents early rejection, promotes lymphocyte apoptosis, and inhibits the upregulation of intragraft interleukin-6 in an orthotopic liver transplant model in the rat

Costimulatory pathways have a pivotal role in the T-cell response to alloantigen. The role of costimulatory blockade with anti-CD154 in orthotopic liver transplantation (OLT) has not been examined previously. This study aims to investigate effects of anti-CD154 and CTLA4-immunoglobulin (Ig) in the early post-OLT period using a major histocompatibility complex-disparate fully arterialized OLT model in the rat. Lewis rats underwent OLT with Dark Agouti liver allografts. Recipients were randomized to receive (1) isotype control, (2) anti-CD154, (3) CTLA4-Ig, or (4) cyclosporine A (CyA). Rats were killed day 8, and specimens were obtained for histological examination, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling, immunohistochemistry, and quantitative reverse-transcriptase polymerase chain reaction. An additional five transplant recipients were treated with anti-CD154 for 14 days postoperatively to assess long-term allograft survival. All isotype control animals died on or before day 6 of acute rejection. Apart from four deaths caused by nonimmunologic causes, all treated recipients survived to day 8. The median survival of rats treated for 14 days with anti-CD154 was greater than 150 days. Serum aspartate aminotransferase and bilirubin levels normalized by day 3 in the CyA group and day 5 in transplant recipients treated with costimulatory blockade. Histologically, there was no difference between isotype controls and CTLA4-Ig-treated animals, whereas anti-CD154-treated transplant recipients had a lower Banff score. CD4+ and CD8+ T-cell infiltrates were prominent in transplant recipients treated with costimulatory blockade. Intragraft analysis showed an increase in lymphocyte apoptosis, Fas ligand messenger RNA expression, and reduction in interleukin-6 gene expression in transplant recipients treated with costimulatory blockade. Costimulatory blockade did not alter intragraft gene expression of other mediators of T-cell priming, differentiation, and effector function compared with isotype control animals. In conclusion, costimulatory blockade prevented acute rejection, enabled long-term survival, and increased intragraft lymphocyte apoptosis in a high-responding rat OLT model.