12/202024

How to Assess the Nutritional Status of Cancer Patients? The PG-SGA Scale Does It All!

How to Assess the Nutritional Status of Cancer Patients? The PG-SGA Scale Does It All!

 

Malnutrition in cancer patients is a form of chronic disease-related malnutrition caused by multiple factors, including malignant tumors and cancer therapies, significantly impacting patients' quality of life and overall survival. The PG-SGA (Patient-Generated Subjective Global Assessment) tool, specifically designed for cancer patients, accurately reflects their nutritional status and has been widely recognized and applied in the global oncology nutrition field.

Expert Insights: Dr. Duge from the Department of General Medicine

Unveils the Fast and Accurate PG-SGA Nutritional Assessment

【The Danger Lies Beyond the Tumor Itself—Malnutrition as a Major Obstacle to Treatment】

Research by the Tumor Nutrition Committee of the Chinese Anti-Cancer Association (IN-SCOC) indicates that the incidence of malnutrition among cancer patients in China is as high as 80.4%, with mild, moderate, and severe malnutrition accounting for 22.2%, 32.1%, and 26.1%, respectively. Additionally, a related survey by the Chinese Anti-Cancer Association found that 68.78% of cancer patients and 55.03% of those with severe malnutrition had never received nutritional therapy. As malnutrition worsens, treatment effectiveness significantly declines, leading to several major impacts:

· Impaired Anti-Tumor Treatment and Increased Complications: Patients undergoing chemotherapy and radiation therapy are prone to side effects such as loss of appetite and oral mucositis. Postoperative wound healing slows down, and the risk of systemic infections, potentially leading to severe complications such as renal impairment.

· Increased Cancer-Related Pain and Reduced Quality of Life: Malnutrition leads to deficiencies in essential nutrients, which may intensify cancer-related pain. It also causes loss of lean body mass (LBM) and adipose tissue, ultimately making daily self-care increasingly difficult for patients.

Early diagnosis and timely treatment are key to cancer prevention. Similarly, cancer patients must actively manage cancer-related malnutrition by starting with a thorough nutritional assessment. Maintaining good nutrition is a crucial step in the fight against cancer.

【PG-SGA Nutritional Assessment: Helping to "Tailor" Nutrition Plans】

 

The PG-SGA (Patient-Generated Subjective Global Assessment) is a nutritional assessment method specifically designed for cancer patients. It is developed based on the Subjective Global Assessment (SGA) and focuses on evaluating the nutritional status of cancer patients.

 

l Why Is PG-SGA Nutritional Assessment Essential for Patients?

Comprehensive Evaluation: The assessment includes both self-assessment by the patient and evaluation by healthcare professionals. This allows patients to fully understand their nutritional status, while doctors gain a complete understanding of the patient’s current nutritional condition.

Evaluation Dimensions: The assessment covers seven key areas: weight, dietary intake, symptoms, physical activity and function, relationship between disease and nutritional needs, metabolic demands, and physical assessment. The broad scope of evaluation helps to precisely detect malnutrition risks.

Assessment Methods: PG-SGA utilizes both qualitative and quantitative evaluation methods, offering a unified approach to assessment. This combination helps derive clinically relevant and actionable results.

 

l  How to Properly Conduct PG-SGA Nutritional Assessment?

Patient Self-Assessment Form

The Patient Self-Assessment Form (Part A) includes four key components: weight, dietary intake, symptoms, and physical function and activity level. The score for Part A is the sum of the scores from these four items.

1/体重（表）weight(table) My current weight is approximately: My current height is approximately: My weight approximately 1 month ago was: My weight approximately 6 months ago was: In the past two weeks, my weight has: · Decreased · Remained the same · Increased Score for this section:

2/进食情况 Dietary Intake In the past month, compared to my usual dietary intake: l No change (0) l More (0) l Less (1) My current eating condition: l Regular diet, but reduced intake (1) l Soft food (2) l Liquid diet (3) l Dependent on oral nutritional supplements (3) l Hardly able to eat anything (4) l Relying on enteral or parenteral nutrition (0) Score for this section:

3/症状Symptoms In the past two weeks, I have experienced the following issues that affected my ability to consume enough food: l No appetite, don’t feel like eating (3) l Vomiting (3) l Diarrhea (3) l Dry mouth (1) l Altered sense of smell (1) l Feeling full quickly (1) l No issues with eating (0) l Nausea (1) l Constipation (1) l Mouth ulcers (2) l Altered taste perception" (1) l Difficulty swallowing (2) l Pain：        (Location) (3) l Other:   (Depression, financial problems, dental issues) (1) Score for this section:

1/活动和身体功能（表）Activities and Physical Functions (Table) In the past month, my activity level was: l Normal, no restrictions (0) l Not as usual, but still able to get up and do light activities (1) l Mostly unwilling to get up, but stayed in bed or a chair for less than half a day (2) l Hardly able to do anything, spent most of the day in bed or in a chair (3) l Almost completely bedridden, unable to get up (3) Score for this section:

 

Assessment Key Points:

· The weight change over the past month is scored. If there is no weight change data for the past month, the weight change over the past 6 months will be used instead.

· A weight loss within the past 2 weeks adds 1 point, while no weight loss in that period gives 0 points.

· The total weight score is the sum of these two factors.

 

 

Patient-Generated Subjective Global Assessment (PG-SGA) Weight Scoring:

Table1: Patient-Generated Subjective Global Assessment (PG-SGA) Weight Scoring
Weight loss within 1 month: >10% 5%~9.9% 3%~4.9% 2%~2.9% 0~1.9%	Rating: 4 3 2 1 0	Weight loss within 6 months: >20% 10%~19.9% 6%~9.9% 2%~5.9% 0~1.9%
Weight loss within 2 weeks:   1
Total score:

 

2.Dietary Intake Assessment: Multiple-choice question. The score is not cumulative; instead, the highest scoring option is selected.

3.Symptoms: Summative Scoring Section. Only symptoms that have frequently occurred in the past two weeks should be selected. Occasional symptoms are not considered for scoring.

4.Physical Activity and Functional Status: This section is a single-choice question, where the option that best reflects the patient's condition is selected for scoring.

 

Medical Staff Assessment Form

The Medical Staff Assessment Form consists of three key components: Impact of Disease on Nutritional Requirements, Metabolic Demands, and physical examination.

Disease: Single or multiple-choice selection with cumulative scoring. If the patient has other diseases not listed, no score is recorded.

Table 2: Disease and Nutrition Relationship
Diseases:	Rating
Cancer	1
AIDS	1
Cachexia due to respiratory or heart disease	1
Presence of open wounds, intestinal fistula, or pressure ulcers	1
Trauma	1
Age over 65	1
Total Score:

 

Stress Status: Cumulative scoring is required, and the patient’s actual measured body temperature should be recorded. If the temperature is normal at the time of assessment, it is considered no fever. The duration of fever refers to the time the current fever has lasted. If different doses of steroids have been used for several consecutive days, the average dose is taken as the steroid dose. Other reasons for steroid use, such as connective tissue diseases, are not evaluated.

	Table 3: Medical Staff Assessment – Stress Score
Stress		None(0 points)	Mild (1 point)	Moderate (2 points)	Severe (3 points)
Fever		None	37.2–38.3°C	38.2–38.8°C	> 38.8°C
Duration of Fever		None	<72h	72h	>72h
Use of Steroids (Prednisone)		None	Low dose (<10mg prednisone or equivalent/day) ·	Medium dose (10–30mg prednisone or equivalent/day)	High dose (>30mg prednisone or equivalent/day)
Total Score:

 

Physical Examination: The examination sequence follows a top-to-bottom approach, from head to toe, including orbital fat pads, brow and temporal muscles, clavicle region, shoulders and scapular region, lower rib fat thickness, triceps skinfold thickness, interosseous muscles of the hand, abdomen, sacral area (to check for ascites), thighs, calves, and ankle edema.

 

Table 4: Medical Staff Assessment – Physical Examination
Items	Normal (0 points)·	Mild (1 point)	Moderate (2 points)	Severe (3 points)
· Fat Reserves · Orbital fat pad · Triceps skinfold thickness · Subcostal fat thickness · Overall fat depletion level · Muscle Condition · Abdomen (abdominal muscles) · Clavicular area (pectoralis major) · Shoulder (deltoid) · Interosseous muscles · Scapular area (latissimus dorsi, trapezius, and deltoid) · Thigh (quadriceps) · Calf (gastrocnemius) · Overall muscle wasting score · Fluid Status · Ankle edema · Foot edema · Ascites
Overall edema score
Total Score

Evaluation Points

· Fat, Muscle, and Fluid Sub-item Scoring:

The final score for each sub-item is determined based on the condition of most assessed areas.If fat loss is mild in most areas, the final fat loss score is mild (1 point).If muscle loss is moderate in most areas, the final muscle loss score is moderate (2 points).

· Total Physical Examination Score:

Among muscle, fat, and fluid assessments, muscle loss carries the highest weight.Therefore, the muscle loss score is taken as the final physical examination score rather than summing up the three categories.

Table 5: Fat Loss Assessment
Fat Reserves	Examination Key Points	0 points	1 points	2 points	3 points
Orbital fat	l Check for orbital hollowing l Assess if the supraorbital ridge is prominent	l No orbital hollowing l supraorbital ridge not prominent	l Mild orbital hollowing l slightly prominent supraorbital ridge	l Intermediate between the two conditions	l Severe orbital hollowing l loose skin, prominent supraorbital ridge
Triceps Skinfold Thickness	Keep the arm bent without pinching the muscle	large amount of adipose tissue	Feels similar to a normal person, slightly reduced	Intermediate between the two conditions	Minimal gap between fingers, almost touching
Subcostal Fat Thickness	l First, pinch the subcostal fat on yourself for comparison l Observe the contour of the lower ribs from the back	Thick fat layer between fingers, ribs not visible; similar to a normal person	Rib contour visible	Intermediate between the two conditions	Minimal gap between fingers, almost touching; prominent lower ribs
Total Fat Loss Score

 

 

Table 6: Muscle Loss Assessment
Fat Reserves	Examination Key Points:	0 points	1 points	2 points	3 points
Temporalis (Temporalis Muscle)	Direct observation, Ask the patient to turn their head to one side	No noticeable hollowing	Mild hollowing	Hollowing	Severe hollowing
Clavicular Area (Pectoralis Major)	Observe the clavicle for prominence	Clavicle not visible (for men); clavicle visible but not prominent (for women)	Clavicle slightly prominent	Clavicle moderately prominent	Clavicle highly prominent
Shoulder (Deltoid Muscle)	Observe the shoulder for prominence, shape, and arm position (hanging down)	Round shape, no prominent deltoid	Mild prominence of acromion	Intermediate between mild and severe prominence	Bony prominence of the acromion and shoulder
Scapular Area (Latissimus Dorsi, Trapezius, and Deltoid)	Ask the patient to push their hands forward and observe the scapula	Scapula not prominent	Mild prominence of scapula, slight indentation between ribs, scapula, shoulder, and spine	Noticeable prominence of scapula and ribs	Scapula clearly visible, with significant indentation between ribs, scapula, shoulder, and spine
Interosseous Muscles	Observe the back of the hand and pinch the space between the thumb and index finger Look for any hollowing in the thenar space	Muscles prominent; may be flat in women	Flat	Intermediate between flat and hollow	Clearly hollow
Total Muscle Wasting Score:

 

Table 7: Edema Assessment
Fat Reserves	Examination Key Points:	0 points	1 points	2 points	3 points
Ankle Edema	Have the patient lie on their back Apply pressure for 5 seconds	No indentation	Mild indentation	Intermediate between the two conditions	Very deep indentation, does not rebound
Sacral Edema	Have the patient lie on their side Apply pressure for 5 seconds	No indentation	Mild indentation	Intermediate between the two conditions	Very deep indentation, does not rebound
Ascites	Check for shifting dullness Assess for fluid wave and whether the abdominal circumference has increased	No shifting dullness, no fluid wave, no increase in abdominal circumference	Shifting dullness present when lying on either side	Intermediate between the two conditions	Patient reports significant abdominal bloating, increased abdominal circumference

 

Comprehensive Assessment

Quantitative Assessment Method:

The total score is calculated by summing the Patient Self-Assessment (Part A) and the Medical Staff Assessment (Part B)..

· 0–1 points: No intervention required; routine follow-up and evaluation should be maintained during treatment.

· 2–3 points: Healthcare providers should provide patient and/or family education. Pharmacological intervention may be considered based on clinical symptoms and assessment results.

· 4–8 points: A registered dietitian should be consulted for intervention. Depending on symptom severity, a physician and a dietitian may collaborate on nutritional intervention.

· ≥9 points: Urgent symptom management and/or simultaneous nutritional intervention are required.

 

Qualitative Assessment Method:

Based on the above assessment and the following comprehensive evaluation table, patients are classified into three categories:

· Well-nourished

· At risk or moderately malnourished

· Severely malnourished

PG-SGA Qualitative Assessment

 

Classification	A (Good nutrition)	B (Suspected or moderate malnutrition)	C (Severe malnutrition)
Weight	l No weight loss or edema      l Or significant recent improvement	l Weight loss of no more than 5% in 1 month l Or weight loss of no more than 10% in 6 months l Or continuous weight loss	l Weight loss exceeding 5% in 1 month l Or weight loss exceeding 10% in 6 months l Or continuous weight loss
Nutritional Intake	No deficiency or significant recent improvement	Intake significantly reduced	Severe reduction in intake
Nutrition-Related Symptoms	No symptoms or significant recent improvement	Symptoms present (refer to Worksheet 3)	Severe symptoms (refer to Worksheet 3)
Functional Status	No impairment or significant recent improvement	Moderate impairment or recent worsening	Severe impairment or significant progressive worsening
Physical Examination	No impairment or chronic impairment with clinical improvement	Mild to moderate loss of body fat/muscle	Significant signs of malnutrition, including edema
Overall Evaluation

Since qualitative assessment correlates well with quantitative assessment, the final evaluation can be unified based on the table below.

Relationship Between PG-SGA Qualitative and Quantitative Assessments

 

Qualitative Evaluation	Quantitative Evaluation
Good Nutrition	0-1 points
Suspected or moderate malnutrition	2-8 points
Severe malnutrition	≥9 points

 

Generally, quantitative assessment is more straightforward, allows for clearer classification of a patient’s nutritional status, has greater clinical applicability, and is more impactful for treatment guidance.

Accurately Identifying Malnutrition is The Foundation for Scientific Treatment

Accurate detection of malnutrition is the prerequisite for scientifically treating it. The PG-SGA assessment method plays a crucial role in designing personalized nutritional plans, ultimately improving the quality of life and prognosis for cancer patients. Patients are encouraged to complete the PG-SGA assessment within 24–48 hours of hospital admission, taking the first proactive step in the right direction to fight cancer!