Comprehensive geriatric assessment (CGA) is a multidimensional and interdisciplinary diagnostic process for medical and functional status (FS) used in elderly patients to evaluate health status. The Karnofsky Performance Scale (KPS) and Physical Performance Test (PPT) have been used as a measure of FS in older patients to screen heath status.

We designed this study to assess and compare the value of KPS and PPT as pre-screening tools for vulnerable elderly cancer patients using the CGA as a gold standard.

This is a prospective interventional study including cancer patients aged more than 70 years. Direct assessments were realized using a questionnaire composed of KPS, PPT and CGA, constructed by the authors after a review of the literature.

One hundred patients were included (median age 76 years–extremes 70–89). KPS and PPT were found to be positively correlated (Pearson correlation coefficient r = 0.680, P value < 0.001) with each other and negatively correlated with CGA with the former having a higher absolute r value (−0.779 vs −0.654 respectively, P < 0.05). All two had poor discrimination capacities when identifying patients having ≥2 impairments on the CGA, by means of a ROC curves analysis (area under the curve (AUC) for KPS = 0.206 versus 0.198 for PPT, with a P value > 0.05 on pair-wise comparison).

Neither KPS nor PPT were found to be good pre-screening tools for vulnerable elderly cancer patients in the outpatient setting. The CGA remains the preferred method for assessing alterations in geriatric domains.