AbstractBackground: oligometastatic breast cancer patients achieved better progression-free survival without significant toxicity, sothis urge patients subgroups identification who might gain more benefit from aggressive local therapy. In comparison toantro posterior, post anterior, and direct post anterior techniques, 3-dimensional conformal irradiation delivered for treatmentof lumbar vertebrae metastasis was much better in the decrease of bowel and spinal cord exposure. Aim of the work: toevaluate clinical outcome gains achieved by 3D radiotherapy versus 2D radiotherapy in certain breast cancer patients withbony oligo metastasis with expected favorable survival.Methods: In a retrospective cohort, 60 patients were enrolled in 2Dversus 3D arm. Treatment and survival outcomes were observed. Results: 3D radiotherapy offer a significantly better painresponse, local control, and lower toxicity than patients were received treatment delivery by 2D radiotherapy with p-value =0.004,0.002 and 0.004 respectively, patients were delivered 2D radiotherapy had shown a progressive disease than thosetreated by 3D radiotherapy of statistical significance p-value = 0.01. The 3D arm was better than the 2D arm in the term ofbetter significant PFS and nonsignificant OS, p-value = 0.04, 0.14 respectively. Conclusion:3D conformal radiotherapy is ofgreat value in the improvement of local control, pain response, progression-free survival, and overall survival with a tolerabletoxicity profile in breast cancer patients diagnosed with bony oligo metastasis.Keywords; Conformal radiotherapy, 2-dimensional radiotherapy, oligometastatic, breast cancer Keywords Keywords; Conformal radiotherapy, 2-dimensional radiotherapy, oligometastatic, breast cancer