Cancer, or the effects of cancer treatments, can sometimes cause malnutrition and weight loss.
Malnutrition is when the body is not getting enough vitamins, minerals and nutrients from the diet, such as protein, to keep healthy and maintain weight.
Reversing malnutrition and helping people living with cancer get the best nutrition is a vital part of prehabilitation.
Nutrition Screening
Score interpretations and interventions
| Score Range | Interpretation | Tiers of prehabilitation | Recommended Intervention |
| 0–1 | No intervention required | Universal | Routine nutrition education may be sufficient |
| 2–3 | Requires patient & family education | Targeted | Consider education and monitoring |
| 4–8 | Requires intervention by a dietitian | Targeted | Includes symptom management and individualized nutrition care |
| ≥9 | Indicates a critical need for improved symptom management and/or intensive nutritional intervention | Specialist | Often associated with cachexia, longer hospital stays, and poorer outcomes |
Notes
- A score of ≥6 is commonly used as a threshold for identifying patients at nutritional risk, especially in outpatient oncology settings
- Some studies suggest ≥7 improves specificity, while ≥6 offers higher sensitivity for detecting malnutrition
- The PG-SGA SF captures patient-reported data on weight change, food intake, symptoms, and activity level—making it a practical tool for early detection and triage
Malnutrition Universal Screening Tool (MUST)
- a five-step screening tool to identify adults who are malnourished or at risk of malnutrition (undernutrition) or obese
- uses current weight, unplanned weight loss and an acute disease effect
- includes management guidelines which can be used to develop a care plan
- used widely in hospitals, community and other care settings and can be used by all care workers
The Royal Marsden Nutrition Screening Tool
- more specifically aimed at people with cancer than MUST
- considers the acute disease effect including nutrition impact symptoms e.g., taste and smell alterations, swallowing problems, abdominal pain
- Sensitive for identifying patients who are malnourished or at risk of malnutrition in the inpatient setting
Nutrition Assessment
Patient-Generated Subjective Global Assessment
Score interpretation and interventions
| Total Score | Interpretation | Tiers of prehabilitation | Recommended Intervention |
| 0–1 | No immediate nutritional intervention required | Universal | Routine monitoring; reinforce healthy habits |
| 2–3 | Suspected or mild malnutrition | Targeted | Education, symptom management, and dietary advice |
| 4–8 | Moderate malnutrition or nutritional risk | Targeted | Referral to dietitian; initiate tailored nutrition support |
| ≥9 | Severe malnutrition or urgent nutritional needs | Specialist | Immediate comprehensive nutrition intervention |
Global Rating Categories
- A – Well nourished
- B – Moderately malnourished or suspected malnutrition
- C – Severely malnourished
These ratings complement the numerical score and help prioritize care.
Key components assessed
- Weight history (recent and long-term changes)
- Food intake (type, consistency, quantity)
- Symptoms (e.g. nausea, pain, early satiety)
- Functional status (activity level, fatigue)
- Metabolic stress (e.g. fever, corticosteroids)
- Physical examination (muscle/fat loss, oedema)
Subjective Global Assessment (SGA)
- Canadian Malnutrition Task Force
- Assessment includes taking a history of recent intake, weight change, gastrointestinal symptoms and a clinical evaluation
Blood Tests
- anaemia is predictor of adverse post-operative outcomes
- measure B12 / folate / iron levels as indicated by sub-type of anaemia
- vitamin D deficiency has been associated with poorer post-operative outcomes
- albumin / prealbumin / zinc have been used as surrogate markers for malnutrition. They may be lowered in inflammatory states (including in patients with cancer) and not accurately reflect true protein state
Sarcopenia
- Sarcopenia is the progressive loss of muscle mass and is associated with poorer outcomes. It can be caused by a combination of lack of exercise and malnutrition
- Gold standard in a research setting is dual-energy X-ray absorptiometry (DXA) or bioelectrical impedance analysis (BIA)
- In a clinical setting, cases are identified when a patient reports symptoms or signs of sarcopenia such as feeling weak, slow walking speed or difficulty rising from a chair
- CT imaging of the psoas muscle can detect sarcopenia. CT scan images obtained as part of radiotherapy planning can also be used to detect sarcopenia