Benjamin H.L. Tan

Cancer cachexia: A systematic literature review of items and domains associated with involuntary weight loss in cancer

BACKGROUND The concept of cancer-related anorexia/cachexia is evolving as its mechanisms are better understood. To support consensus processes towards an updated definition and classification system, we systematically reviewed the literature for items and domains associated with involuntary weight loss in cancer. METHODS Two search strings (cachexia, cancer) explored five databases from 1976 to 2007. Citations, abstracts and papers were included if they were original work, in English/German language, and explored an item to distinguish advanced cancer patients with variable degrees of involuntary weight loss. The items were grouped into the 5 domains proposed by formal expert meetings. RESULTS Of 14,344 citations, 1275 abstracts and 585 papers reviewed, 71 papers were included (6325 patients; 40-50% gastrointestinal, 10-20% lung cancer). No single domain or item could consistently distinguish cancer patients with or without weight loss or having various degrees of weight loss. Anorexia and decreased nutritional intake were unexpectedly weakly related with weight loss. Explanations for this could be the imprecise measurement methods for nutritional intake, symptom interactions, and the importance of systemic inflammation as a catabolic drive. Data on muscle mass and strength is scarce and the impact of cachexia on physical and psychosocial function has not been widely assessed. CONCLUSIONS Current data support a modular concept of cancer cachexia with a variable combination of reduced nutritional intake and catabolic/hyper-metabolic changes. The heterogeneity in the literature revealed by this review underlines the importance of an agreed definition and classification of cancer cachexia.

The influence of systemic inflammation, dietary intake and stage of disease on rate of weight loss in patients with gastro-oesophageal cancer

Although weight loss is often a dominant symptom in patients with upper gastrointestinal malignancy, there is a lack of objective evidence describing changes in nutritional status and potential associations between weight loss, food intake, markers of systemic inflammation and stage of disease in such patients. Two hundred and twenty patients diagnosed with gastric/oesophageal cancer were studied. Patients underwent nutritional assessment consisting of calculation of body mass index, measurement of weight loss, dysphagia scoring and estimation of dietary intake. Serum acute-phase protein concentrations were determined by enzyme-linked immunosorbent assay. In all, 182 (83%) patients had lost weight at diagnosis (median loss, 7% body weight). Weight loss was associated with poor performance status, advanced disease stage, dysphagia, reduced dietary intake and elevated serum C-reactive protein (CRP) concentrations. Multiple regression identified dietary intake (estimate of effect, 38%), serum CRP concentrations (estimate of effect, 34%) and stage of disease (estimate of effect, 28%) as independent variables in determining degree of weight loss. Mechanisms other than reduced dietary intake or mechanical obstruction by the tumour appear to be involved in the nutritional decline in patients with gastro-oesophageal malignancy. Recognition that systemic inflammation plays a role in nutritional depletion may inform the development of appropriate therapeutic strategies to ameliorate weight loss, making patients more tolerant of cancer-modifying treatments such as chemotherapy.

Cancer cachexia is associated with the IL10 −1082 gene promoter polymorphism in patients with gastroesophageal malignancy

BACKGROUND The genetic predisposition of the host to local or systemic inflammation may contribute to the effect of cancer cachexia. OBJECTIVE We investigated the relation between cytokine polymorphisms (IL1B -511, IL6 -174, IL10 -1082, TNFA -308, and LTA +252) and markers of nutritional status among patients with gastroesophageal cancer to determine whether any such association was reflected by cytokine concentrations in the tumor or plasma compartments. DESIGN Patients (n = 203) with a diagnosis of gastroesophageal cancer underwent nutritional assessment (body mass index, anthropometric measures, dysphagia scoring, and estimation of dietary intake). Single nucleotide polymorphism genotyping was performed by TaqMan allelic discrimination genotyping. Serum cytokine and C-reactive protein concentrations were determined by enzyme-linked immunosorbent assay. Tumor tissue cytokine protein concentrations (n = 56) were determined by using the Cytometric Bead Array System. RESULTS IL10 GG and IL6 CC polymorphisms were associated with elevated serum C-reactive protein concentrations, and the IL6 CC genotype was also associated with elevated tumor tissue cytokine concentrations. At diagnosis, the IL10 GG, but not the IL6, genotype was linked with increased total weight loss: 4.9% for AA, 7.1% for AG, and 12.0% for GG (P = 0.007). Serum C-reactive protein concentrations correlated with increased weight loss (r = 0.24, P < 0.001). Compared with other genotypes, the IL10 GG genotype retained an independent association in determining the extent of weight loss on multivariate analysis (95% CI: 0.52, 3.43; P = 0.008). Possession of the GG allele was associated with a 2.3 times increased risk of developing cachexia (95% CI: 1.2, 4.3; P = 0.014). CONCLUSION These data suggest that the IL10 genotype of the host can influence the development of cachexia among patients with gastroesophageal malignancy.

Plasma MIC-1 correlates with systemic inflammation but is not an independent determinant of nutritional status or survival in oesophago-gastric cancer

Background:Macrophage inhibitory cytokine-1(MIC-1) is a potential modulator of systemic inflammation and nutritional depletion, both of which are adverse prognostic factors in oesophago-gastric cancer (OGC).Methods:Plasma MIC-1, systemic inflammation (defined as plasma C-reactive protein (CRP) of ⩾10 mg l–1 or modified Glasgow prognostic score (mGPS) of ⩾1), and nutritional status were assessed in newly diagnosed OGC patients (n=293). Healthy volunteers (n=35) served as controls.Results:MIC-1 was elevated in patients (median=1371 pg ml–1; range 141–39 053) when compared with controls (median=377 pg ml–1; range 141–3786; P<0.001). Patients with gastric tumours (median=1592 pg ml–1; range 141–12 643) showed higher MIC-1 concentrations than patients with junctional (median=1337 pg ml–1; range 383–39 053) and oesophageal tumours (median=1180 pg ml–1; range 258–31 184; P=0.015). Patients showed a median weight loss of 6.4% (range 0.0–33.4%), and 42% of patients had an mGPS of ⩾1 or plasma CRP of ⩾10 mg l–1 (median=9 mg l–1; range 1–200). MIC-1 correlated positively with disease stage (r2=0.217; P<0.001), age (r2=0.332; P<0.001), CRP (r2=0.314; P<0.001), and mGPS (r2=0.336; P<0.001), and negatively with Karnofsky Performance Score (r2=−0.269; P<0.001). However, although MIC-1 correlated weakly with dietary intake (r2=0.157; P=0.031), it did not correlate with weight loss, BMI, or anthropometry. Patients with MIC-1 levels in the upper quartile showed reduced survival (median=204 days; 95% CI 157–251) when compared with patients with MIC-1 levels in the lower three quartiles (median=316 days; 95% CI 259–373; P=0.036), but MIC-1 was not an independent prognostic indicator.Conclusions:There is no independent link between plasma MIC-1 levels and depleted nutritional status or survival in OGC.

P‐selectin genotype is associated with the development of cancer cachexia

The variable predisposition to cachexia may, in part, be due to the interaction of host genotype. We analyzed 129 single nucleotide polymorphisms (SNPs) in 80 genes for association with cachexia based on degree of weight loss (>5, >10, >15%) as well as weight loss in the presence of systemic inflammation (C‐reactive protein, >10 mg/l). 775 cancer patients were studied with a validation association study performed on an independently recruited cohort (n = 101) of cancer patients. The C allele (minor allele frequency 10.7%) of the rs6136 (SELP) SNP was found to be associated with weight loss >10% both in the discovery study (odds ratio (OR) 0.52; 95% confidence intervals (CI), 0.29–0.93; p = 0.026) and the validation study (OR 0.09, 95% CI 0.01–0.98, p = 0.035). In separate studies, induction of muscle atrophy gene expression was investigated using qPCR following either tumour‐induced cachexia in rats or intra‐peritoneal injection of lipopolysaccharide in mice. P‐selectin was found to be significantly upregulated in muscle in both models. Identification of P‐selectin as relevant in both animal models and in cachectic cancer patients supports this as a risk factor/potential mediator in cachexia.

Biomarkers for cancer cachexia: is there also a genetic component to cachexia?

IntroductionCancer cachexia is a severe debilitating disorder, which causes significant morbidity and mortality. In clinical practice, cachexia is often not treated until a late stage, when therapeutic options are limited.ObjectiveIt is therefore of great interest to analyse early biomarkers of this syndrome.ConclusionIn this review article, we summarise recent biomarkers found in various body compartments. We also explore the likelihood of a genetic predisposition to cachexia and focus on the potential role of single nucleotide polymorphisms in genes coding for pro- and anti-inflammatory cytokines, and ‘atrogenes’ associated with wasting in skeletal muscle.

Frequency of the mitochondrial DNA 4977bp deletion in oesophageal mucosa during the progression of Barrett's oesophagus

PURPOSE The mechanisms of the progression of Barretts oesophagus (BO) to oesophageal adenocarcinoma (OA) are poorly understood. The frequency of the 4977bp deletion in mitochondrial DNA (mtDNA) was investigated in specimens ranging from normal oesophageal tissue to OA in order to investigate whether this deletion represents a useful biomarker of disease progression. METHODS The presence of the 4977bp deletion was screened by PCR amplification from 70 specimens in total. RESULTS The frequency of specimens with the 4977bp deletion increased in relation to the degree of dysplasia (8.3% in normal squamous epithelium; 15.4% in BO; 40% in low grade dysplasia (LGD); 69.2% in high-grade dysplasia and 90% in para-tumoural tissue). However, the frequency of the deletion reduced sharply in OA specimens (16.7%; p<0.001). CONCLUSION The mtDNA 4977bp deletion may be useful as a biomarker to detect the severity of dysplasia but not the presence of OA.

New genetic signatures associated with cancer cachexia as defined by low skeletal muscle index and weight loss

Cachexia affects the majority with advanced cancer. Based on current demographic and clinical factors, it is not possible to predict who will develop cachexia or not. Such variation may, in part, be due to genotype. It has recently been proposed to extend the diagnostic criteria for cachexia to include a direct measure of low skeletal muscle index (LSMI) in addition to weight loss (WL). We aimed to explore our panel of candidate single nucleotide polymorphism (SNPs) for association with WL +/− computerized tomography‐defined LSMI. We also explored whether the transcription in muscle of identified genes was altered according to such cachexia phenotype

Absence of correlation between serum CRP levels and mitochondrial D-loop DNA mutations in gastro-oesophageal adenocarcinoma.

INTRODUCTION Both inflammation and mitochondrial DNA (mtDNA) mutation are thought to play a role in the many human cancers. The aim of this study was to evaluate the relationship between inflammation and accumulation of mitochondrial DNA (mtDNA) mutations in the D-loop region in carcinogenesis of gastro-oesophageal adenocarcinomas. MATERIALS AND METHODS Blood samples of 20 patients with gastro-oesophageal adenocarcinoma were taken for measurement of serum C-reactive protein (CRP) concentration. Direct sequencing of mtDNA in the D-loop region was done in the 20 adenocarcinoma samples and their corresponding surrounding non-cancerous tissue. Sequences were compared with existing mtDNA databases to identify mutations. RESULTS mtDNA mutations in the D-loop region occur commonly with almost identical frequency in both non-cancerous tissue (3.0 ± 1.6) and adenocarcinoma (3.1 ± 1.9) (P = 0.916, paired t-test). CRP levels are not predictive of the number of D-loop mutations in both adenocarcinoma (β: -0.131; 95% CI: -2.354-1.364; P = 0.583) and non-cancerous tissue samples (β: 0.130; 95% CI: -1.125-1.933; P = 0.586). Five new mutations were identified that were not recorded previously in mtDNA databases. CONCLUSION D-loop mtDNA mutations are common in both gastro-oesophageal adenocarcinoma and surrounding non-cancerous tissue. However, the accumulation of such mutations appears to occur independent of systemic inflammation. The frequency of D-loop mutations is likely not useful as a marker for carcinogenesis in gastro-oesophageal adenocarcinoma.