10111 Background: Single fraction radiotherapy (RT) is standard of care for palliation of pain from bone metastases (ASTRO IJROBP 2011 79:965). But costly, complex, multi-fraction RT is quite often used for palliation of symptoms from various organs. Health care costs are burgeoning (ASCO JCO 2012 30: 1715). Costs can be constrained by judiciously reducing use of unnecessary multi-fraction RT in pts with limited life expectancy. But radiation oncologists’ ability to predict survival is inaccurate. (Chow IJROBP 2005 61:870). Hence we assessed clinical utility of Neutrophil Lymphocyte ratio (NLR) - a routinely available biomarker. Methods: 233 patients (pts) undergoing palliative RT over a 3 month at Nottingham University Hospital. Predominant Tumour SITES: Lung 28% Breast 13% Prostate 13% Colorectal 9% Gastro-Oesophageal 5% Myeloma 5% Bladder 5%. Predominant HISTOLOGY: Adenocarcinoma 61% Squamous Cell 14%. NLR available for 158 pts. Results: A NLR of 4.5 was highly predictive of 90-day mortality & overall survival in an unselected real world population. (Table). No survival benefit seen for multi-fraction RT over single fraction RT across all tumour sites. On survival analysis by Cox regression, increased NLR was significant with a hazard ratio of 2.2 (95% CI 1.3 to 3.7) whereas total radiation dose, use of multiple fractions , age, serum haemoglobin, serum albumin & histology were not significant. Conclusions: In palliative care of advanced cancer, for pts with high NLR (>4.5), Single fraction RT should be the standard of care for palliation of symptoms. [Table: see text]