Accidental Detection of Pulmonary Embolism According To CT in Cancer Patients with Low and Intermediate Risk of Thrombosis – Features of Radiology Diagnosis and Risk Factors

Purpose: To evaluate the factors associated with asymptomatic pulmonary embolism (PE) in oncology patients with low/intermediate risk (Horan scale), as well as to determine the methodological features of CT, which make it possible to identify CT signs of PE in the absence of clinical symptoms. Material and methods: Out of 104 patients who underwent contrast-enhanced CT, 65 with low and intermediate risk on the Horan scale were selected, in which the data were evaluated: gender, age, ECOG scale, tumor localization and stage, type of antitumor drug therapy, taking glucocorticosteroids and anticoagulants before PE was detected, the timing of PE detection, the presence of thrombosis of any localization, hospitalization in the previous 3 months before PE detection for any reason, surgical benefits, injuries and fractures in the anamnesis, a new coronavirus infection (with laboratory confirmation), radiation therapy, varicose veins of the lower extremities, diabetes mellitus, chronic kidney disease, coronary heart disease, hypertension, the presence of a venous port for chemotherapy. Laboratory parameters were evaluated: the level of hemoglobin, leukocytes, platelets, D-dimer, the risk of thrombosis was assessed according to the following scales: Korana, PROTECHT, CONCO, Vienna CATSCORE, ONCOTEV, COMPASS, as well as survival after PE detection. Results: When distributing patients according to the risk of thrombosis, when using the COMPASS scale, patients at high risk of thrombosis in this sample were more often identified (87.7 %). The remaining scales considered classified patients at high risk from 9.2 % to 41.5 %. The median overall survival was 16 months. Correlation evaluation of the Horan, PROTECHT, CONCO, Vienna CATSCORE, ONCOTEV, and COMPASS scales revealed that all scales except COMPASS VTE significantly correlated with each other. During the correlation analysis, a moderate (k=0.243) correlation of the COMPASS scale with the PE index (Quanadli) was noted with a significance of p=0.055. The tumor T index correlated (k = –0.288, p=0.025); endocrinotherapy (k=0.283, p=0.025); radiation therapy (k=0.257, p=0.042); an increase in the level of D-Dimer (k=0.309, p=0.015). However, no influence of factors on the PE index was noted during the regression analysis. The most reasonable protocol for CT patient contrast to detect asymptomatic PE is the split-bolus technique.