Background: Patients with advanced cancer and bone metastases may have unmet palliative care needs that go unnoticed during clinical oncological practice. This observational study describes palliative care needs and interventions identified because of participation in a clinical study. Methods: Patients with advanced cancer and painful bone metastases included in the Palliative Radiotherapy and Inflammation Study (PRAIS) aiming to predict the response of radiotherapy (RT) were eligible. All patients met with the palliative care (PC) study team prior to start of RT, after they had completed patient reported outcome measures (PROMs). Symptoms prompting interventions by the study team were documented in the patient charts and reviewed.Results: One hundred-and thirty-three patients were reviewed; 63% males, mean age 65 and mean Karnofsky score (KPS) 73. Interventions were initiated in 50% (n=67) of the patients. Most common were changed opioid management (69%), treatment of constipation (43%) and nausea (24%) and nutritional advices (21%). Patients receiving interventions had lower mean KPS (70 vs 77 p <0.001), shorter survival time after study inclusion (median 28 vs. 57.5 weeks p = 0.005) and were more often opioid naïve (12% vs 39% p <.001) compared with the non-intervention group. Conclusions: Adverse symptoms are often not identified in routine oncological consultations prior to RT for cancer pain. Special attention should be directed to frail patients. These findings call for an early and systematic integration of palliative care in patients with advanced cancer.Trial registration: ClinicalTrials.gov NCT02107664