Cancer cachexia is a metabolic disorder in cancer patients experiencing uncontrolled weight loss. While cancer cachexia occurs in all cancer types, it is most common in pancreatic, gastro-oesophageal, head and neck, lung, and colorectal cancers.
There is a very high rate of cancer cachexia for patients nearing the end of life, but it also arises in smaller frequencies in patients with curable cancers. While nutritional interventions are ineffective at treating cachexia in cancer patients, successful treatment of the underlying cancer can reverse the symptoms.
Cancer cachexia correlates to poor overall survival, and this subset of patients are less responsive to cancer therapies, including chemotherapy.
One of the major drivers of cancer cachexia is adipose tissue loss. There are two major types of adipose tissues, white and brown. White adipose tissue, fatty tissue responsible for storing energy within the body for use by other organs, contains subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT).
SAT is located throughout the body beneath the skin, and VAT is concentrated around the abdomen. While VAT is linked to other metabolic syndromes, including insulin resistance and diabetes, the contribution of SAT and VAT to the development of cancer cachexia is not well understood.
A recent study published in Clinical Nutrition investigated the contributions of SAT and VAT in gastric cancer patients with cachexia. The study enrolled over 1600 gastric cancer patients, including 411 with cachexia and 1216 without cachexia. Patients received a CT scan that the research team used to measure SAT and VAT around the L3 vertebra. Calculations made from these scans determined the areas of SAT and VAT following normalization for patient height.
The researchers found that SAT was significantly lower in cancer patients with cachexia than non-cachexia patients. Further, among the cachexia patients, low SAT correlated with poor survival.
The study found no difference in VAT between the cachexia and non-cachexia patients, nor was there any effect of VAT on survival.
This study show confirms that adipose tissues loss is a key feature of cachexia among gastric cancer patients. Additionally, the study demonstrates that SAT, but not VAT, is a driving factor of cachexia in this cohort of patients. The authors propose the use of SAT as a prognostic factor for cachexic gastric cancer patients.