Admassie, Daniel(MD ConsultantRadiologist, prof. of Radiology)Gezzehagn, Hiwot (MD, ConsultantRadiologist)Zenebe, Moges(MD, ConsultantRadiologist)Tolasa, Fikadu2020-11-242023-11-052020-11-242023-11-052019-08http://etd.aau.edu.et/handle/123456789/23483Background: Skeletal metastases account for 70% of all malignant bone lesions and are seen in vast number of primary cancers. Lung cancer, breast cancer, renal carcinoma and prostate cancer account for approximately 80% of all skeletal metastases. CT scan imaging has an important role in the detection, diagnosis, prognosis treatment, planning and follow up monitoring of bone metastases. Substantial proportion of patient with advanced cancer and bone develop skeletal related events including pathologic fracture, spinal cord compression,myelosuppression and hypercalcemia which usuallyassociated with moderate or severepain. Objectives: To determine pattern and distribution of skeletal metastases in patient with known and unknown primary cancer by using CT scan at Tikur Anbessa teaching referral hospital. Method: Prospective cross-sectional descriptive study of all patient with skeletal metastases diagnosed by CT scan followed by using data collection sheet (questionnaires) and medical records during study period at Black Lion Hospital from October 2018 to July 2019. Result: A total of 140 patients with known or unknown primary tumor with bone metastasis were included in the study from October 2018 to July 2019 GC. 81 0f them were female and 59 were male.The mean age at presentation was 52 years +/- 14.75(age range of 37.25-66.75years) and majority of the patients were found in age group of 40-60(42.9%)years.Among the involved bone the most common affected was spine (62.1%), followed by pelvis (41.2%).The most commonly known primary cancers metastasis to bone were breast (30.7%) followed by lung (29%) and prostate (15.7%) tumors.Lytic type (51%) of the bone lesion is the frequent morphologic type followed by mixed (34%) and sclerotic (17%).Among the studied patients (65%) patients had bone pain symptom while (19.3%)had pathological fracture and (15.7%)patients had spinal cord compression symptom. Discussion: Majority of patients during the study period were female and the mean age of prestation was 52 years +/-14.75. Among the primary tumors breast, lung, prostate, renal and thyroid cancer were the common tumors identified in our study. In this study spine was the most common bone involved followed by pelvis and ribs and sternum. When we see the morphology of bone lesion identified on CT scan lytic is the most common followed by mixed andscelrosis.Pain was the most common clinical pentation of the studied patient.en-USRadiology,Computer Tomographic , bone metastasisThesis