Pulmonary artery intima sarcoma is an uncommon but fatal tumor, which often masquerades chronic thromboembolic pulmonary hypertension (CTEPH) and in the present case Takayasu arteritis. Pulmonary arterial pressure is mildly elevated in the presence of extensive proximal lesions. A parenchyma thin-walled cavitary lesion may be a sign of pulmonary extravasation of the tumor.
A 31-year-old woman was referred to our hospital for persistent dyspnea on exertion (New York Heart Association, NYHA, class 2) and CTEPH. She had a history of hookworm infection, and 4 years ago she had an episode of acute chest pain and shortness of breath. A second episode occurred 3 months ago, being interpreted as acute pulmonary embolism precipitated by the combination of pill and smoking.
Clinical examination revealed clubbing, a prominent pulmonary component of the second heart sound and a left parasternal systolic ejection murmur. Peripheral arterial pulsations were normal, there was no carotid arteries murmur, and blood pressure was the same on both arms (99/60 mmHg). The remainder of the examination was unremarkable.
Routine laboratory examination did not show any signs of inflammation. Electrocardiogram was normal. Echocardiogram showed a thickened mitral valve, a tricuspid regurgitation of 3/4 with an estimated systolic pulmonary arterial pressure (PAP) of 60 mmHg, and a markedly dilated, mildly hypocontractile right ventricle. Right heart catherisation showed a mean PAP of 28 mmHg, a cardiac index of 2.91 L/min/m2, and a total pulmonary vascular resistance of 450 dyne.sec.cm−5. Exercise capacity was impaired as shown by a 6 min walking distance of 553 meters (69% of predicted) with desaturation from 96 to 90% and by an ergospirometry showing a peak oxygen consumption of 22 ml/min/kg with desaturation from 97 to 83%. Lung function was normal except for a low diffusion capacity of 46%. Chest X-ray showed enlarged pulmonary arteries with a right parahilar nodule, perfusion scan multiple lobar and segmental defects, and pulmonary angiography amputations of the right lower lobe and left upper lobe arteries, with multiple aneurysmal dilatations of the branches of the right upper lobe artery (Figure
Pulmonary angiography suggestive for chronic thromboembolic pulmonary hypertension (CTEPH) with unexplained multiple dilatations of the branches of the right upper lobar artery.
(a) Initial PET scan. Metabolic active lesions in the right upper lobe which diameter increased over time, with appearance of a metabolically active cavity in the right lower lobe. (b) Follow-up PET scan after 2 months of oral corticosteroids. The diameter of the metabolic active lesions in the right upper lobe increased over time, with appearance of a metabolically active cavity in the right lower lobe.
In our patient, a 4-item differential diagnosis was discussed: (1) CTEPH, but angiography was somewhat atypical and pulmonary hypertension was mild; (2) Takayasu arteritis [
Follow-up chest X-ray shows a thin-walled cavitary lesion in the right lower lobe (white arrow).
CT thorax shows an initial lung infiltrate (a) evolving into a large thin-walled cavitary lesion in the right lower lobe (b).
This section of the lung by autopsy showed a dilated vessel with tumor (intima sarcoma, rectangle) and extravascular extension of the tumor (circle). (Hematoxylin and eosin, ×12.5).
Pulmonary artery intima sarcoma, first described by Mandelstamm in 1923 [
This case illustrates that intima sarcoma is often initially misdiagnosed, usually because it mimics CTEPH, but in this case because it mimics large-vessel arteritis. It draws attention to the need to raise differential diagnosis in patients with atypical features of CTEPH such as clubbing [
In conclusion, pulmonary artery sarcoma is an uncommon but fatal tumor which often masquerades CTEPH. In the present case it presents more like arteritis.
Extensive tumor resection with wide security margins and pulmonary artery reconstruction is the treatment of choice when the patient is scheduled for elective surgery but pulmonary endarterectomy can also be performed. The sequence infiltration-(infarction)-cavitation may be a sign of extravascular extension into the lung parenchyma.
There are no conflict of interests to disclose.