Background: The survival rates for patients with advanced cancer have increased over time. Many patients experience symptoms and functional limitations that impair activities of daily living and limit quality of life. A number of these health problems are amenable to physical therapist treatment. However, physical therapists caring for patients with advanced cancer require special training and skills. Objective: The study aimed to assess the educational needs and clinical uncertainties of Dutch physical therapists in relation to treatment of patients with advanced cancer. Design: This was a mixed methods study. Methods: A survey and 2 focus groups were conducted among physical therapists working in primary care who had previously received at least basic oncology training. Results: A total of 162 physical therapists completed the survey. The most frequently reported educational needs were related to effective interprofessional collaboration (61.7%), knowledge of medical treatment (49.4%), and current evidence on physical therapist interventions in this population (49.4%). In the focus groups, physical therapists (n = 17) voiced uncertainties about treating patients with bone metastases, setting realistic goals, when and how to end a treatment episode, interprofessional collaboration, finding and using evidence, and using clinimetrics. Conclusion: These results support the need for specific education programs for physical therapists working with advanced cancer patients to increase the availability of high-quality oncology rehabilitation for this population.