A retrospective study in the detection of i̇nci̇dental pulmonary tromboembolism in cancer pati̇ents

ABSTRACT Aim The aim of this study is to show the frequency of incidentally found (pulmonary tromboembolism) PTE in oncological patients and evaluate dispersion of incidents in terms of underlying primary tumor and seek risk factors associated with incidental PTE. Mention of findings in the final radiology reports have also been investigated and compared with literature findings. Material and Method: We retrospectively reviewed findings of one thousand consecutive cases who referred to Dicle University Department of Radiology between March 2012 and September 2013 with confirmed diagnosis of various tumor types and underwent contrast enhanced thorax CT using either Philips Brilliance 64 detectors or Toshiba Activion 16 detectors row CT scanners. We created subset of patient groups according to each primary diagnosis. Thyroid and parathyroid gland cancers are included to 'endocrine tumors' group whereas larynx, parotid and brain tumors are classified as 'other' tumors because of their relative rarity. First of all, we sought patients in terms of presence or absence of PTE. Second, we evaluated those who have positive findings for incidental PTE in terms of locations of emboli, group of underlying primary tumor, risk factors, companian findings in lung parenchyma and mention of findings in final radiology reports. Findings Among one thousand oncology patients, 46 (4.6%) individuals (29 females, 17 males) found to have incidental PTE. Of positive patients, the highest proportion (%24) was belong to breast cancer group (n=11). Amidst subjects of positive PTE, least incidents (one incident per group) were encountered in the patients with tumors arose from following sites; kidney, liver, bone-soft tissue, bladder and pancreas. Nevertheless, PTE was not evident in subjects with lymphoma, endocrin tumors, testis tumor and those with tumor belongs to 'other' group. The most common location for pulmonary emboli was the lower lobe branch of right pulmonary artery (n=33, 71.7%). The most common site for venous trombi was deep venous structures of lower extremities. Twenty (43.4%) subjects suffered from deep venous trombosis while 21 (45.6%) individuals showed no evidence of trombosis at deep venous system. Evident PTE had not been reported in final radiology reports of 21 cases. The commonest companian findings in lung parenchyma (n=16, 34.7%) were subsegmentary atelectasis and fibrous bands. Conclusion Tendency to thromboembolic events is a known feature of oncological patients. Of one thousand subjects we reviewed, 46 (4.6%) patients showed the evidence of incidental PTE on thorax CT imaging, which is concordant with literature findings. Contrast enhanced thoracic CT is one of the widely performed fundamental imaging techniques in follow up imaging of oncological patients. In order to decrease mortality and morbidity rate of incidental PTE, pulmonary arteries must be thorougly scrutinized on those studies even in asymptomatic patients, as they could be easily overlooked. Keywords: İncidentally pulmonary thromboembolism (PTE), cancer, Multi-slice computed tomograpy (MSCT)