Validation of the prognostic model for palliative radiotherapy in older patients with cancer

BACKGROUND Older patients are more likely to have a poor performance status and comorbidities. There is a reluctance to extensively investigate and treat older patients. As elderly individuals and patients with neoplasms each increase in number, palliative treatment of older patients is expected to grow as an issue. AIM To investigated the role of palliative radiotherapy in older patients and patients who were expected to demonstrate a therapeutic effect. METHODS From February 2019 to February 2022, 33 patients aged ≥ 80 years underwent palliative radiotherapy. The prognosis in palliative care study predictor (PiPS), palliative prognostic index (PPI), and delirium-palliative prognostic score (D-PaP) models were used for prognosis prediction. D-PaP scores calculated according to the doctor's prediction of clinical prediction of survival (CPS) were excluded and then analyzed for comparison. Radiation was prescribed at a dose of 2.5-7 Gy per fraction, up to a median of 39 Gy10 (range, 28-75 Gy10). RESULTS The median follow-up was 2.4 months (range, 0.2-27.5 months), and 28 patients (84.8%) showed subjective symptom improvements following treatment. The 2- and 6-month survival rates of all patients were 91.5% and 91.5%, respectively. According to regression analysis, the performance status index, symptom type, and radiation dose all showed no significant correlation with the treatment response. When survival was expected for > 55 days in the PiPS model, the 2-month survival rate was 94.4%. For patients with PPI and D-PaP-CPS values of 0-3.9 points, the 2-month survival rates were 90.0% and 100%, respectively. For patients with a score of ≥ 4 points, the 2-month survival rates were 37.5% and 0%, respectively. CONCLUSION This study shows that the prognosis prediction model used in palliative care can be used to identify patients suitable for treatment.