Screening for Pre-Cachexia in Non-Small Cell Lung Cancer: the Tools We Have, the Tools We Need
Creators: name: Wyler, Susan
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2011

description: The end-stage of non-small cell lung cancer is often marked by severe anorexia and cachexia, which independent of tumor progression leads to death, usually within 3 months. For many years in cancer care, the term cachexia was used in advanced stages of malnutrition without making a clear distinction between proteolysis (the catabolism of lean muscle tissue), generalized wasting associated with weight loss, and loss of adipose tissue. The term sarcopenia was used loosely and sometimes interchangeably, whether referring to the muscle loss associated with old age or that in cancer disease. This imprecision obviated the ability to clearly identify and effectively treat these conditions. In February 2011, a panel of experts from such international organizations as the National Cancer Research Institute (NCRI) and the European Palliative Care Research Collaborative (EPCRC) reached a consensus that established a codified definition of cancer cachexia, identifying it as an intractable loss of skeletal muscle mass, with or without loss of fat mass, marked by negative protein and energy balance caused by a combination of reduced oral intake and aberrant metabolism. Unlike starvation, this condition cannot be reversed by traditional nutrition support, leading to lack of functionality and in up to 30 percent of cases, to death regardless of tumor load. They also separated the syndrome into three different stages: pre-cachexia, cachexia, and refractory cachexia. Historically, efficient nutritional screening tools have focused on weight loss as the major symptom for identifying the malnutrition of cancer cachexia. Yet evidence shows that in cancer patients, especially those with non-small cell lung cancer, loss of skeletal muscle with impaired functionality and increase in systemic inflammation, as evidenced by CRP, fibrinogen, and inflammatory cytokines, especially IL-6 and TNF-α, along with the onset of insulin resistance may occur before any sign of weight loss. Many studies have shown that once severe malnutrition is evident, nutritional support of any kind is unsuccessful at reversing the course of the disease or even providing palliative benefits. This is because most support is offered in the refractory state, when chemotherapy is equally ineffective. During the middle cachexic stage, when chemotherapy, radiation, and/or surgery can sometimes halt or delay tumor progression, attempts to replenish energy and protein stores may mildly reverse weight loss for a time; but whether or not there is the possibility of rebuilding lost skeletal muscle is still being debated. There is a major role for trained dietitians to play in screening for pre­-cachexia because some of the least expensive, most noninvasive ways that have preciously been used to identify early muscle wasting involve anthropometric techniques long used in the profession: hand-grip strength along with mid-arm muscle circumference (MAMC) and calf muscle circumference combined with systematic tracking of weight with scales and dietary records. To study the possible benefits of early nutritional intervention for NSCLC, we must pinpoint early makers of sarcopenia and develop appropriate screening tools that are sensitive to both anthropometric measurements and biochemical makers as well as comprehensive assessment techniques that may enhance the ability to treat pre-cachexia before weight loss appears.