الفهرس 
Tumors and Nutritional Status Cancer CachexiaOnly 14 pages are availabe for public view
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Abstract
Cancer cachexia refers to a complex and multifactorial syndrome characterized by anorexia or the spontaneous and unintended loss of appetite, generalized host tissue wasting, skeletal muscle atrophy, immune dysfunction and a variety of metabolic alterations.
Nutritional assessment should start with patient history and physical examination, anthropometric parameters and specefic laboratory tests. The history should reveal usual body weight and any recent weight change. Physical examination may reveal signs of malnutrition such as Muscle wasting, loss of muscle strength and depletion of fat stores. Anthropometric measurements includes Mid-arm muscle circumference and scapular and triceps skin folds. laboratory tests includes Concentrations of serum proteins such as retinol-binding protein, transferrin, prealbumin, and albumin can be used to estimate the degree of visceral protein depletion.
Therapeutic goals for PN in cancer patients are the improvement of function and outcome by Preventing and treating under-nutrition and cachexia, enhancing compliance with anti-tumor treatments, controlling some adverse effects of anti-tumor therapies and improving quality of life.
Many indications for parenteral nutrition parallel those for enteral nutrition (weight loss or reduction in food intake more than 7-10 days) but only those who for whatever reason cannot feed orally or enterally are candidates to receive parenteral nutrition.
Standard nutritional regimen may be recommended for short term parenteral nutrition while in cachectic patient receiving intravenous feeding for several weeks, high fat –to glucose ratio may be advised because these patients maintain high capacity to metabolize fats.
The essential amino acids, omega-3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), may also play a role in reversing the effects of cachexia. Omega-3 fatty acids have been shown to inhibit the production of tumor derived factors, proteolysis, inducing-factor (PIF) and lipid-mobilizing factor (LMF), to help prevent fat and muscle breakdown.
Parenteral nutrition can be administered through peripheral or central Veins. When planning parenteral nutrition (PN), the proper choice, insertion and nursing of the venous access are of paramount importance. It is recommended that peripheral PN (given through a short peripheral cannula or through a midline catheter) should be used only for a limited period of time, and only when using nutrient solutions whose osmolarity does not exceed 850 mOsm/L.
Parenteral nutrition indicated in:
1- In severely malnourished patients who are responding to chemotherapy and in whom gastrointestinal or other toxicities preclude adequate enteral intake for 7 to 10 days or longer.
2- When the patient cannot eat and enteral route not feasible.
3- At risk of malnutrition (NPO) greater than 7 days.
4- PN is recommended in patients with severe mucositis or severe radiation enteritis.
5- Peri-operative PN is recommended in malnourished candidates for artificial nutrition, when EN is not possible.
6- In Hematopoietic stem cell transplant (HSCT) patients PN should be reserved for those with severe mucositis, ileus, or intractable vomiting. Clear recommendation can be made as to the time of introduction of PN in HSCT patients.
Parenteral nutrition is contraindicated in:
1- In well-nourished or mildly malnourished patients undergoing chemotherapy, radiation therapy, or surgery.
2- In patients with rapidly progressive malignant disease who fail to respond to treatment.
3- In patients who have evidence of terminal disease and are not candidates for further antitumor therapy.
Several complications of PN have been recognized and some of them can be life threatening. The complications of PN are divided into (1) mechanical, (2) infectious and (3) metabolic. Mechanical complications are related to insertion and care of the central venous catheter (CVC). Septic complications are the result of catheter-associated infections. Metabolic complications refer to high or low serum levels of any components of PN solution, liver disease and metabolic bone disease. PN complications are associated with increased mortality and affect the quality of life of PN patients.
Although PN supplies nutrients to the tumor, there is no evidence that this has deleterious effects on the outcome. This consideration should therefore have no influence on the decision to feed a cancer patient when PN is clinically indicated.