Are we better a decade later in the accuracy of survival prediction by palliative radiation oncologists?

Background: Clinician predicted survival (CPS) plays a crucial role in palliative care, informing physicians of appropriate treatment best suited to the patient. The primary objective of this study was to assess the accuracy of CPS of cancer patients referred for palliative radiotherapy. Secondary objectives included an analysis of factors predictive of accurate CPS, comparisons of the accuracy of survival predictions over subsequent clinic visits, and comparisons to the previous study in the Rapid Response Radiotherapy Program (RRRP) in 2005. Methods: CPS was provided by one of four radiation oncologists from August 2014 to March 2017. Karnofsky Performance Status (KPS), primary cancer site, and sites of metastases were recorded. Date of death was retrieved from the Patient Care System (PCS) and Excelicare. Mean difference between actual survival (AS) and CPS was used to determine the accuracy of survival predictions. Results: One-hundred seventy-two patients were included in the final analysis. Survival was largely overestimated (n=135, 78.5%), with CPS being overestimated by 19.0 weeks on average. KPS (P=0.2), primary cancer site (P=0.08), and various sites of metastases were not significantly related to CPS accuracy. Gender was significantly related to CPS accuracy after multivariable analysis (P=0.04), but was no longer significant after excluding prostate and breast cancer patients in multivariable analysis (P=0.2). The mean difference between AS and CPS did not significantly change over subsequent visits (P=0.5) and CPS accuracy decreased significantly compared to the previous RRRP study (P=0.04). Conclusions: The survival estimates provided by radiation oncologists are inaccurately overestimated. Further research should aim to increase the accuracy of CPS in order to improve patient outcomes.