Introduction: We are carrying 108 genetic mutations that may cause different malformations that we transmit to our off spring. Some do not bring any life problems, others have phenotypic expression. Methods: Case presentation: We report the case of a female patient, aged 31 years, with no history of cardiovascular disease, hospitalized for dyspnea at rest; she denies smoking and oral contraceptive use, has no family history of thromboembolic disease. Investigations revealed pulmonary embolism. The patient was further investigated for the cause of pulmonary thromboembolism. Results: – It was suspected the existence of a procoagulant status, but thrombophilia screening tests have been changes; – Anticardiolipin and antiphospholipid antibodies were negative; – Manifestation of a paraneoplastic syndrome. In this regard we performed: thoracic-abdominal-pelvic CT, colonoscopy, upper GI endoscopy, tumor markers, which denied a possible malignancy, but showed hepatosplenomegaly with signs of portal hypertension in the context of intraparenchymal splenic arteriovenous shunts; splenic artery aneurysm. Conclusions: Pulmonary embolism in a young patient without a major contributing factor. Evaluation of a splenic arteriovenous malformation which is complicated by pulmonary embolism (paradoxical embolism rare) in a young patient without cardiovascular risk factors. With regard to a young patient, we considered the possibility of an occult cancer without clinical and laboratory evidence to date. Recent studies have found that about a quarter of patients with DVT or pulmonary embolism where cause is not identified were later diagnosed with a malignancy within about two years (most commonly lymphoma, lung or ovarian cancer).