ECOG Performance Status

ECOG Performance Status (ECOG PS), also known as WHO Performance Status or Zubrod Score, is a scale developed by the Eastern Cooperative Oncology Group to assess functional status in cancer patients. The scale ranges from 0 (fully active) to 5 (death), quantifying the patient's ability to perform daily activities and self-care. It is a fundamental tool for: 1) Assessing eligibility for chemotherapy protocols, 2) Stratifying prognosis, 3) Monitoring disease progression, 4) Standardized multidisciplinary communication, 5) Documentation in medical records and clinical research.

To assess ECOG PS: 1) Observe the patient and obtain history about daily activities, 2) Ask about: ability to work, need for rest, self-care ability, time spent in bed/chair, 3) Select the category that best describes the patient's current state, 4) Record ECOG PS in medical records with assessment date, 5) Reassess periodically, especially before therapeutic changes. IMPORTANT: If uncertain between two levels, choose the worse (higher number). Assessment should reflect functional status related to cancer disease, not limitations from other comorbidities (e.g., severe arthritis).

While both assess functional status, there are important differences:

• •Ask the patient directly about activities in recent days
• •Observe general appearance, gait and alertness level during consultation
• •Consider caregiver reports if patient has cognitive impairment
• •If uncertain between two consecutive levels, choose the worse (higher number)
• •Always reassess before starting new chemotherapy cycle
• •Document ECOG changes over time in medical records
• •Don't let a single non-oncologic comorbidity determine ECOG

1) **Subjectivity**: There may be variability in interpretation between different evaluators. Training and standardization are important. 2) **Comorbidities**: Difficult to differentiate limitations from cancer disease vs other conditions (heart disease, arthritis). 3) **Fluctuation**: Functional status may vary day to day. Record the most recent and representative assessment. 4) **Culture and Context**: Concepts like 'light work' may vary culturally. 5) **Not Multidimensional**: Does not capture specific quality of life domains (pain, anxiety, nutrition). 6) **Performance ≠ Isolated Prognosis**: Should be interpreted together with other factors (tumor type, stage, biomarkers, response to previous treatments).