Contribution of diet, tumour volume and patient-related factors to weight loss in patients with colorectal liver metastases

Physiological characterization of a mouse model of cachexia in colorectal liver metastases

Loss of skeletal muscle mass and function (cachexia) is severe in patients with colorectal liver metastases because of the large increase in resting energy expenditure but remains understudied because of a lack of suitable preclinical models. Our aim was to characterize a novel preclinical model of cachexia in colorectal liver metastases. We tested the hypothesis that mice with colorectal liver metastases would exhibit cachexia, as evidenced by a reduction in liver-free body mass, muscle mass, and physiological impairment. Twelve-week-old male CBA mice received an intrasplenic injection of Ringer solution (sham) or murine colorectal cancer cells (MoCR) to induce colorectal liver metastases. At end-point (20-29 days), the livers of MoCR mice were infiltrated completely with metastases, and MoCR mice had reduced liver-free body mass, muscle mass, and epididymal fat mass compared with sham controls (P < 0.03). MoCR mice exhibited impaired rotarod performance and grip strength (P < 0.03). Histochemical analyses of tibialis anterior muscles from MoCR mice revealed muscle fiber atrophy and reduced oxidative enzyme activity (P < 0.001). Adipose tissue remodeling was evident in MoCR mice, with reduced adipocyte diameter and greater infiltration of nonadipocyte tissue (P < 0.05). These findings reveal the MoCR mouse model exhibits significant cachexia and is a suitable preclinical model of cachexia in colorectal liver metastases. This model should be used for identifying effective treatments for cachexia to improve quality of life and reduce mortality in patients with colorectal liver metastases.

Is there a genetic cause of appetite loss?-an explorative study in 1,853 cancer patients

BACKGROUND

Appetite loss has a major impact on cancer patients. It is exceedingly prevalent, is a prognostic indicator and is associated with inferior quality of life. Cachexia is a multi-factorial syndrome defined by a negative protein and energy balance, driven by a variable combination of reduced food intake and abnormal metabolism. Not all cancer patients that experience weight loss have appetite loss, and the pathophysiology between cachexia and appetite loss may thus be different. Knowledge of pathophysiology of appetite loss in cancer patients is still limited. The primary object of this study was to explore the association with 93 predefined candidate single-nucleotide polymorphisms (SNPs) and appetite loss in cancer patients to possibly generate new theories of the pathophysiology of the condition.

METHODS

A total of 1,853 cancer patients were phenotyped according to appetite loss and then genotyped.

RESULTS

After allowing for multiple testing, there was no statistically significant association between any of the SNPs analysed and appetite loss. The ten most significant SNPs in the co-dominant model had observed odds ratios varying from 0.72 to 1.28.

CONCLUSIONS

This large exploratory study could not find any associations with loss of appetite and 93 SNPs with a potential to be involved in appetite loss in cancer patients. This does not however rule out genes putative role in the development of the symptom, but the observed odds ratios are close to one which makes it unlikely that any of the individual SNPs explored in the present study have great importance.

Non-surgical oncology - Guidelines on Parenteral Nutrition, Chapter 19

Reduced nutritional state is associated with unfavourable outcomes and a lower quality of life in patients with malignancies. Patients with active tumour disease frequently have insufficient food intake. The resting energy expenditure in cancer patients can be increased, decreased, or remain unchanged compared to predicted values. Tumours may result in varying degrees of systemic pro-inflammatory processes with secondary effects on all significant metabolic pathways. Therapeutic objectives are to stabilise nutritional state with oral/enteral nutrition and parenteral nutrition (PN) and thus to prevent or reduce progressive weight loss. The maintenance or improvement of quality of life, and the increase in the effectiveness and a reduction in the side-effects of antitumor therapy are further objectives. Indications for PN in tumour patients are essentially identical to those in patients with benign illnesses, with preference given to oral or enteral nutrition when feasible. A combined nutritional concept is preferred if oral or enteral nutrition are possible but not sufficient. There are generally no accepted standards for ideal energy and nutrient intakes in oncological patients, particularly when exclusive artificial nutrition is administered. The use of PN as a general accompaniment to radiotherapy or chemotherapy is not indicated, but PN is indicated in chronic severe radiogenic enteritis or after allogenic transplantation with pronounced mucositis or GvH-related gastrointestinal damage for prolonged periods, with particular attention to increased risk of bleeding and infection. No PN is necessary in the terminal phase.

Effect of adenosine 5'-triphosphate infusions on the nutritional status and survival of preterminal cancer patients

The aim of the study was to investigate the effect of intravenous infusions of adenosine 5'-triphosphate (ATP) on nutritional status and survival in preterminal cancer patients. Ninety-nine preterminal cancer patients (estimated life expectancy 1-6 months) with mixed tumor types were randomly allocated to receive either intravenous ATP weekly (8-10 h/week, maximum 50 microg/kg/min) for 8 weeks, or no ATP (control group). Nutritional status parameters were assessed until 8 weeks, and analyzed by repeated-measures analysis of covariance. Cox proportional hazards models were fitted to assess the effect of ATP on short-term (0-8 weeks) and long-term (0-6 months) survival. Fifty-one patients were randomized to ATP and 48 to the control group. Results showed a significant favorable effect of ATP on triceps skin fold thickness [between-group difference per 8 weeks 1.76 mm, 95% confidence interval (CI): 0.48-3.12 mm; P = 0.009] and on short-term survival [0-8 weeks hazard ratio (HR): 0.40, 95% CI: 0.17-0.95; P = 0.037]. In weight-stable patients and in lung cancer patients, long-term survival (0-6 months) was also significantly better in ATP-treated patients (weight-stable patients HR: 0.40, 95% CI: 0.19-0.83; P = 0.014; patients with lung cancer: HR: 0.35, 95% CI: 0.14-0.88; P = 0.025). In conclusion, in this population of preterminal cancer patients, ATP infusions, at the dose and schedule studied, had a favorable effect on triceps skin fold thickness and survival, especially in weight-stable patients and patients with lung cancer. Larger studies are warranted to confirm these findings and to further define the effect of ATP on tumor growth and survival.

ESPEN Guidelines on Parenteral Nutrition: non-surgical oncology

Parenteral nutrition offers the possibility of increasing or ensuring nutrient intake in patients in whom normal food intake is inadequate and enteral nutrition is not feasible, is contraindicated or is not accepted by the patient. These guidelines are intended to provide evidence-based recommendations for the use of parenteral nutrition in cancer patients. They were developed by an interdisciplinary expert group in accordance with accepted standards, are based on the most relevant publications of the last 30 years and share many of the conclusions of the ESPEN guidelines on enteral nutrition in oncology. Under-nutrition and cachexia occur frequently in cancer patients and are indicators of poor prognosis and, per se, responsible for excess morbidity and mortality. Many indications for parenteral nutrition parallel those for enteral nutrition (weight loss or reduction in food intake for more than 7-10 days), but only those who, for whatever reason cannot be fed orally or enterally, are candidates to receive parenteral nutrition. A standard nutritional regimen may be recommended for short-term parenteral nutrition, while in cachectic patients receiving intravenous feeding for several weeks a high fat-to-glucose ratio may be advised because these patients maintain a high capacity to metabolize fats. The limited nutritional response to the parenteral nutrition reflects more the presence of metabolic derangements which are characteristic of the cachexia syndrome (or merely the short duration of the nutritional support) rather than the inadequacy of the nutritional regimen. Perioperative parenteral nutrition is only recommended in malnourished patients if enteral nutrition is not feasible. In non-surgical well-nourished oncologic patients routine parenteral nutrition is not recommended because it has proved to offer no advantage and is associated with increased morbidity. A benefit, however, is reported in patients undergoing hematopoietic stem cell transplantation. Short-term parenteral nutrition is however commonly accepted in patients with acute gastrointestinal complications from chemotherapy and radiotherapy, and long-term (home) parenteral nutrition will sometimes be a life-saving maneuver in patients with sub acute/chronic radiation enteropathy. In incurable cancer patients home parenteral nutrition may be recommended in hypophagic/(sub)obstructed patients (if there is an acceptable performance status) if they are expected to die from starvation/under nutrition prior to tumor spread.

A viscerally driven cachexia syndrome in patients with advanced colorectal cancer: contributions of organ and tumor mass to whole-body energy demands

BACKGROUND

Cancer cachexia-associated weight loss is poorly understood; energetically demanding tissues (eg, organ and tumor mass) and resting energy expenditure (REE) are reported to increase with advanced cancer.

OBJECTIVE

The objective was to quantify the potential contribution of increasing masses of energetically demanding tissues to REE with colorectal cancer cachexia progression.

DESIGN

A longitudinal computed tomography (CT) image review was performed to quantify organ size (liver, including metastases, and spleen) and peripheral tissues (skeletal muscle and adipose tissue) during colorectal cancer cachexia progression (n = 34). Body composition was prospectively evaluated by CT and dual-energy X-ray absorptiometry, and REE was determined by indirect calorimetry in advanced colorectal cancer patients (n = 18).

RESULTS

Eleven months from death, the liver (2.3 +/- 0.7 kg) and spleen (0.32 +/- 0.2 kg) were larger than reference values. One month from death, liver weight increased to 3.0 +/- 1.5 kg (P = 0.010), spleen showed a trend to increase (P = 0.077), and concurrent losses of muscle (4.2 kg) and fat (3.5 kg) (P < 0.05) were observed. The estimated percentage of fat-free mass (FFM) occupied by the liver increased from 4.5% to 7.0% (P < 0.001). The most rapid loss of peripheral tissues and liver and metastases gain occurred within 3 mo of death. A positive linear relation existed between liver mass and measured whole-body REE (r(2) = 0.35, P = 0.010); because liver accounted for a larger percentage of FFM, measured REE . kg FFM(-1) . d(-1) increased (r(2) = 0.35, P = 0.010).

CONCLUSIONS

Increases in mass and in the proportion of high metabolic rate tissues, including liver and tumor, represented a cumulative incremental REE of approximately 17,700 kcal during the last 3 mo of life and may contribute substantially to cachexia-associated weight loss.

Bioelectric impedance spectroscopy underestimates fat-free mass compared to dual energy X-ray absorptiometry in incurable cancer patients

BACKGROUND/OBJECTIVES

Weight loss is frequently seen in advanced cancer. Bioelectrical impedance spectroscopy (BIS) is a convenient method for estimating body composition. We examined in a prospective, comparative study if BIS could accurately estimate fat-free mass (FFM) in cancer patients compared to dual-energy X-ray absorptiometry (DXA).

SUBJECTS/METHODS

The study was based on 132 consecutive incurable cancer patients with solid tumours in a University hospital outpatient clinic. Comparison of FFM from DXA and BIS with standard and revised equations. Bland-Altman plots, t-tests and linear regression analysis were used to evaluate agreement and differences between methods.

RESULTS

BIS significantly underestimated mean FFM with 7.6+/-4.7 kg compared to DXA (P<0.001). Bias was significantly correlated to % weight loss (r=0.32), systemic inflammation as measured by C-reactive protein (r=0.29), malnutrition as assessed by low insulin-like growth factor-1 (r=-0.23) and inversely to the per cent body fat estimated by DXA (P=-0.61) and body mass index (BMI; r=-0.30). Revised BIS equations taking BMI into account reduced bias significantly but still with great individual variation.

CONCLUSIONS

BIS by standard equations grossly underestimates FFM compared to DXA in cancer patients. This bias is related to weight loss, malnutrition and systemic inflammation. Revised equations improved FFM estimates, but with large individual variation. Thus, BIS with standard equations is not suitable to estimate FFM in patients with cachexia, inflammation and malnutrition.

B vitamins deficiency and decreased anti-oxidative state in patients with liver cancer

BACKGROUND

This study examined the status of oxidative stress and B vitamins in hepatocellular carcinoma (HCC) patients in different tumor-node-metastasis stages. Patients were divided into two groups as I + II (n = 21) and III + IV (n = 19).

METHODS

Plasma levels of lipid oxidation, alpha-tocopherol, beta-carotene, vitamin C, glutathione and the activity of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, catalase, and xanthine oxidase) were determined for evaluating oxidative status. Blood B vitamins (B(1), B(2), B(6), B(12), and folate) and serum ghrelin were analyzed, and the relationship between serum ghrelin and vitamins B(2) (or B(6)) was evaluated.

RESULTS

HCC patients at III + IV stage showed significantly lower ghrelin, higher cholesterol, triglyceride, and uric acid than patients at I + II stage and healthy subjects (P < 0.05). Plasma lipid oxidation level in HCC patients was significantly greater than healthy subjects (P < 0.05). The activity of glutathione peroxidase, superoxide dismutase or catalase was significantly decreased, but xanthine oxidase activity was significantly elevated in HCC patients (P < 0.05). Plasma level of glutathione and vitamin C, not alpha-tocopherol and beta-carotene, in HCC patients was significantly lower (P < 0.05). Vitamins B(2) and B(6) levels in red blood cells from these HCC patients were significantly lower (P < 0.05).

CONCLUSION

This study provided novel clinical findings regarding the status of oxidative stress and B vitamins in HCC patients. Plasma glutathione level may be a proper biomarker for evaluating oxidative status for HCC patients. Our data indicate that HCC patients might need B vitamins supplementation. The increased serum level of triglyceride and cholesterol might be a consequence of an impaired hepatic fat metabolism, and might be improved by a lower fat administration to these patients.

Symptoms and weight loss in patients with gastrointestinal and lung cancer at presentation

INTRODUCTION

Weight loss is an independent prognostic factor for decreased survival in cancer patients. The effectiveness of treatment is impaired in patients with weight loss. The aetiology of this weight loss is complex and poorly characterised. Decreased calorie intake may be important. The reasons for decreased intake are unknown.

AIMS AND METHODS

To determine in adult patients with cancer, who had not started chemotherapy or radiotherapy, the prevalence of symptoms which carry a risk to nutritional status and how these relate to weight loss, tumour burden and primary tumour site. New patients referred for treatment of any form of gastrointestinal (GI) cancer, non-small cell lung cancer or lung mesothelioma completed a validated questionnaire recording symptoms contributing to weight loss (Patient-generated Subjective Global Assessment--PG-SGA). In a subset of patients without metastatic disease, computed tomography scans were assessed to determine tumour burden.

RESULTS

Between August and October 2004, 122 patients with GI and 29 with lung cancers were recruited. There were 48% of GI and 28% of lung cancer patients who had lost weight. Sixty-two percent of the patients had one or more symptoms at presentation. The frequency of symptoms varied according to the site of disease. The most common symptom at all tumour sites was loss of appetite (38%). There was a weak but significant correlation between the number of symptoms and amount of weight loss (r=0.347). Patients reporting a reduced food intake had more symptoms than patients who had not lost weight. Tumour burden did not correlate with weight loss.

CONCLUSION

The symptoms in cancer patients occur across different types of primary tumours, may affect food intake and have a part in causing weight loss. More information on the role of symptom management in improving nutritional status is needed.

ESPEN Guidelines on Enteral Nutrition: Non-surgical oncology

Enteral nutrition (EN) by means of oral nutritional supplements (ONS) and tube feeding (TF) offers the possibility of increasing or ensuring nutrient intake in cases where normal food intake is inadequate. These guidelines are intended to give evidence-based recommendations for the use of ONS and TF in cancer patients. They were developed by an interdisciplinary expert group in accordance with officially accepted standards, are based on all relevant publications since 1985 and were discussed and accepted in a consensus conference. Undernutrition and cachexia occur frequently in cancer patients and are indicators of poor prognosis. EN should be started if undernutrition already exists or if food intake is markedly reduced for more than 7-10 days. Standard formulae are recommended for EN. Nutritional needs generally are comparable to non-cancer subjects. In cachectic patients metabolic modulators such as progestins, steroids and possibly eicosapentaenoic acid may help to improve nutritional status. EN is indicated preoperatively for 5-7 days in cancer patients undergoing major abdominal surgery. During radiotherapy of head/neck and gastrointestinal regions dietary counselling and ONS prevent weight loss and interruption of radiotherapy. Routine EN is not indicated during (high-dose) chemotherapy.

Appetite and Cancer-Associated Anorexia: A Review

Appetite is governed by peripheral hormones and central neurotransmitters that act on the arcuate nucleus of the hypothalamus and nucleus tactus solitarius of the brainstem. Cancer anorexia appears to be the result of an imbalance between neuropeptide-Y and pro-opiomelanocortin signals favoring pro-opiomelanocortin. Many of the appetite stimulants redress this imbalance. Most of our understanding of appetite neurophysiology and tumor-associated anorexia is derived from animals and has not been verified in humans. There have been few clinical trials and very little translational research on anorexia despite its prevalence in cancer.

Serum tryptophan decrease correlates with immune activation and impaired quality of life in colorectal cancer

Cancer-related indoleamine (2,3)-dioxygenase up-regulation by interferon-gamma might influence quality of life by depleting serum tryptophan. We correlated serum tryptophan levels with immune activation and quality of life in patients with colorectal liver metastases. Venous blood was sampled from patients with primary colorectal cancer and from patients with metachronous colorectal liver metastases who completed quality of life and psychological questionnaires. Serum tryptophan, kynurenine, neopterin, interleukin 2 soluble receptor alpha (IL-2 sRalpha), soluble tumour necrosis factor receptor I (sTNF RI), interleukin 6, and C-reactive protein were measured. Liver metastasis volume was estimated by computerised tomography, and survival from blood sampling was noted. Sixty-six patients with colorectal cancer were studied (39 males; median age 66 years) of whom 25 had colorectal liver metastases only (17 males; median age 62 years; median liver metastasis volume 208 ml; median survival 234 days). Reduced serum tryptophan was significantly associated with Rotterdam Symptom Checklist physical symptom (r=-0.51, P=0.01) and Sickness Impact Profile (r=-0.42, P=0.04) scores, and correlated with increased serum neopterin (r=-0.36, P=0.003), IL-2 sRalpha (r=-0.51, P=0.01) and sTNF RI (r=-0.45, P=0.02) levels. Stepwise regression analyses suggested that serum tryptophan was an independent predictor of Rotterdam Symptom Checklist physical symptom (regression coefficient -20.78, P=0.01) and Sickness Impact Profile (regression coefficient -109.09, P=0.04) scores. The results supported a role for interferon-gamma-mediated serum tryptophan decrease in cancer-induced quality of life deterioration.

The quality of quality of life studies in general surgical journals

BACKGROUND

There has been a tremendous increase in interest on quality of life in surgical research. An increase in interest does not necessarily translate into better research. This study evaluates surgical articles that claim to measure or make some conclusion on quality of life.

STUDY DESIGN

All articles published in the calendar years 1996 and 1999 that purported to assess quality of life as end points or make some conclusion about quality of life were chosen for review from eight general surgical journals. Articles were assessed for use of a quality of life instrument, type of instrument, validation of the instrument, appropriateness of the instrument for the hypothesis, quality of statistical analysis, and adherence to the Gill and Feinstein criteria.

RESULTS

Of the 18 articles published in 1996, 72% used a quality of life instrument. Eighteen instruments were used in 13 studies: 7 generic, 10 disease-specific, and 1 ad hoc. Forty-three percent were validated, 39% were appropriate for the study hypothesis, 39% had correct statistical analysis. The majority did not meet the Gill and Feinstein criteria. Of the 24 studies published in 1999, 63% used a quality of life instrument. Twenty-two instruments were used in 15 studies: 11 generic, 5 disease-specific, and 6 ad hoc. Fifty-five percent were validated, 45% were appropriate, 45% had correct statistical analysis. Once again, the majority did not meet the Gill and Feinstein criteria.

CONCLUSIONS

Despite the emphasis on quality of life outcomes, a substantial number of studies made errors in conceptually defining quality of life and in use of quality of life instruments. Researchers and journal reviewers need to be better versed on the techniques of quality of life research.