Cancer Cachexia

Definition:

Cancer cachexia or cancer associated fatigue is defined as a multi factorial syndrome characterized by an ongoing loss of skeletal muscle mass(with or without loss of fat mass) that cannot be fully reversed by conventional nutritional support and leads to progressive functional impairment.

The characteristic feature is the negative protein energy balance that occurs due to reduction in the food intake and an abnormal metabolism.

Classification:

There are 3 stages of relevance clinically, forming a spectrum, however not all of these subjects traverse the entire spectrum.

1. Precachecia: The early clinical signs like anorexia and metabolic signs like impaired glucose test precede weight loss (≤5%). The progression varies and depends on the cancer type and staging, low food intake, any systemic inflammation, poor response to anti cancer therapy.
2. Cachexia: A stable weight loss more than 5% over 6 months OR a Body mass index (BMI) of lesser than 20 kg/m² OR sacrcopenia and ongoing weight loss of more than 2%, but not yet entered the refractory stage classified as cachexia.
3. Refractory cachexia: Very advanced cancer OR rapidly progressive cancer, unresponsive to anticancer therapy. Associated with active catabolism and the factors associated with active management of weight loss here no longer stand appropriate. Low performance status and a life expectancy of less than 3 months are characteristic.

Diagnosis of cancer cachexia

• BMI <20 and any degree of weight loss >2%;
• Weight loss >5% over past 6 months (in absence of simple starvation)
• Appendicular skeletal muscle index consistent with sarcopenia (males <7·26 kg/m²; females <5·45 kg/m²) and any degree of weight loss >2%

Assessment

Muscle mass and strength: Cross sectional imaging CT or MRI, dual energy Xray imaging, bioimpedence analysis and anthopometry mainly including the mid arm girth.

Anorexia and reduced food intake: Quantification of protein may be relevant. The mechanisms behind this may be chemo sensory disturbances, reduced upper gastrointestinal mobility, distal tract dysmobility. The secondary causes include stomatitis, consti[ation, dyspnoea, pain and poor dietary habits.

Hypercatabolism: This could be sue to tumor mediated side effects or systemic inflammation. Contributing factors include insulin resistance, long duration high dose corticosteroid, an elevation in the resting energy expenditure, hypogoadism.

Psychosocial and Functional aspects: Patient reported outcomes for physical functioning including European Organisation for Research and Treatment of Cancer, Quality of life Questionnaire, Patient completed Eastern Coperative Oncology Group questionnaire.This can be followed by activity meters and checklists. The psycho social aspects could be identified by routine questions abut the persons psychological status.

Management

There are 4 basic steps of treatment strategies:

1. Correcting the cause of the impaired nutritional intake
2. Adequate nutritional support
3. Multimodal cancer cachexia intervention:
4. Detecting any related psycho social distress and treating the same

Multimodal anabolic interventions are best in the symptom management. Individualized nutrition and exercise optimize the drug effects Concelling including behavioral change, anticancer or antineoplastic treatment, total parenteral nutrition, pro kinetics, progestins, cannabinoids, Eicosapentaenoic acid, Cyclo-oxygenase inhibitors, Corticosteroids and exercise interventions are the treatments.

Exercise interventions:

Mechanisms:

• High Intensity Interval training for 8 weeks has an impact on stage III and stage IV non-small cell lung cancer in patients who are receiving chemotherapy. These patients had a high risk of respiratory failure due to cancer cachexia and exercise training helped improve their lung capacity.
• Progressive resistance exercise training(2-3 days a week for 12 weks) improved the patients compliance and lean body mass by 1-2 Kgs. However its effectiveness is yet to be determined in the head and neck cancer group receiving radiation therapy.
• Aerobic exercise are beneficial in terms that it increases the mitochondial biogensis and reduces the proteolysis by reducing the inflammation.
• Pedometer based exercises(7 week) help in improving the skeletal mass, functional capacity and quality of life in cancer cachexia on chemotherapy.