BackgroundrnOncology patients have a fourfold higher risk for developing pulmonary embolism than that of the generalrnpopulation. Acute pulmonary embolism (PE) is a common and often fatal disease. Furthermore, most cases ofrnPE that eventuallycause fatality are clinically unsuspected and therefore go untreated.rnFinding of incidental PE in oncologic patients significantly affects management and prognosis of patients.rnDiagnosis of PE leads to start of therapeutic anticoagulation and prevents embolic recurrence that is associatedrnwith substantial morbidity and mortality.rnArnlthough the MDCT protocol for CT pulmonary angiography differs from that used for routine chest CT,rnmodern CT systems, along with high-concentration contrast media, enable detection of pulmonary emboli evenrnin routine chest CT, increasing the frequencyof detection of clinically unsuspected pulmonary embolism.rn2rnObjectivernThis study is designed to assess prevalence of incidentalpulmonary embolism in oncologic patients detected byrnchest computed tomography.rnMethodrnHospital based prospectivecross-sectional study conducted at TASH to address the specific objective during thernstudy period (July, 2018-January 2019 G.C).This study was conducted among oncologic patients beingrnevaluated at TikurAnbessa Specialized Hospital who have chest CT imaging during the study period. Chest CTrnwas evaluated for the presence of abnormalities.rnThe study population included all oncologic patients having chest CT imaging during the data collection period.rnData was collected by evaluating the CT by radiologist. The data was checked for clarity and completeness.rnComputerized data analysis was conducted by using SPSS version 20.0 software. rnRESULTrnThe prevalence of incidental PE was 1.7% in this study. A total of 10 patients out of 573 patients had incidentalrnPE. The most common primary malignancy was GIT malignancy (30.9%). The other malignancies werernhematologic malignancies among 12.9%, breast cancer in 12.6%, and cancers of the genitourinary tract in 7.7%.rnthe rest of patients had varieties of different cancer types.80% of the patients with PE had multiple PE and 20%rnhad single PE. rnThe most commonly involved part of the lung was RLL which was involved in all cases of incidental PE.rnFollowed by LLL which was involved in 60%. In general, the upper lobes and the RML were involved in 40%rnof the cases, each. All cases of single PE occurred in the RLL. rn3rnThe most frequently involved divisions of the pulmonary were the lobar branches in 80% of the PE casesrnfollowed by segmental branches (70%). The main division was involved in 40% of the cases, while thernsubsegmental division was involved in none of the cases.rnLimitation of the studyrn-Lack of good pulmonary arterial opacification and motion artifacts which can limit detection of PE.rn-Lack of properly handled patientâ€™s chart.rn-Limited sample size.rnCONCLUSIONrnThe prevalence of incidental PE detected on routine chest CT scan is 1.7% with no detected small artery PE.rnThe risk of incidental PE was higher in older age and advanced malignancy. The diagnosis of incidental PE hasrnsignificantly changed the management in all of these patients.rnGood pulmonary arterial contrastopacificationis required for diagnosis.