A combination therapy for treating advanced cancer, comprises, first, performing targeted low dose radiation therapy on a recipient tumoral site to generate an inflammation zone and an immuno-stimulant effect, including release of cytokines and chemokines. Secondly, hematopoietic cells from a suitable donor are administered intravenously in order to initiate an allogeneic reaction. These cells could be collected either as PBMC from an adult donor, or from an UCB donation. The post-radiotherapy inflammation zone will attract the newly injected donor cells to the tumor bed, triggering an immunological cancer cell rejection. The cellular response in the recipient is monitored and post-treatment evaluation for recipients side effects is also provided.