ECOG or Karnofsky Performance Status to Assess Functionality in Glioblastoma Patients Among Different Observers

Purpose: Glioblastoma (GB) patients usually have symptoms that affect their functional status, and medical staff, as well as the patients and their caregivers, might have different perceptions about it. The performance status is important to establish a patient’s survival prediction and treatment decisions. This study was aimed to explore whether health care providers, patients, and caregivers have a common perception of patients’ functional statuses and to investigate in further studies whether the functional scales used in oncology clinical practice are objective tools to evaluate brain tumour patients. Methods: GB patients treated at our Neuro-Oncology Unit were evaluated once using Eastern Cooperative Oncology Group Performance Status (ECOG) and Karnofsky Performance Status (KPS) by a medical oncologist (MO), an independent investigator (II), the patient and the patient’s main caregiver. Results: Fifty patients were enrolled. Concordance in KPS evaluation among the four observers was low (Fleiss’ Kappa=0.354; p<0.001) and moderate in ECOG one (Fleiss’ K=0.424; p<0.001). Pairing the observers, the concordance between the MO and II was strong (KPS Cohen’s Kappa=0.731; p<0.001, ECOG Cohen’s Kappa=0.741; p=0.001), whereas it was poor between the patient and MO (KPS Cohen’s Kappa=0.250; p=0.007. ECOG Cohen’s Kappa=0.241; p=0.009) and between the caregiver and MO (KPS Cohen’s Kappa=0.350; p<0.001. ECOG Cohen’s Kappa=0.346; p=0.000). Conclusion: Concordance among the observers was poor or moderate according to the functional scale used. Particularly, caregivers’ perception of the patients’ functional status was frequently worse than that of the professionals.