Multiple pulmonary nodules with halo sign: A case of primary pulmonary sarcoma

A 69-year-old transsexual woman presented with a 1-month history of cough, dyspnoea and haemoptysis. She had medical history of arterial hypertension, HIV controlled with antiretroviral treatment and hepatitis B virus. She carried breast prosthesis and had history of multiple subcutaneous silicone injections.

A first contrast-enhanced thoracic CT showed multiple and bilateral randomly distributed lung nodules with halo sign (Figure 1). 

After biopsy of a lingula nodule, a chest radiograph was performed, showing multiple bilateral nodular opacities and post-surgical alterations in left hemithorax (Figura 2a y 2b).

After two months, a significant worsening was observed, with increase in the size and number of lung nodules, all of them with halo sign. A new pleural effusion was also visualised (Figure 3).

A third contrast-enhanced chest CT performed 20 days after the second one, due to clinical worsening of the patient, showed a rapid increase in the number and size of the lung nodules (Figure 4).

Pulmonary angiosarcoma is a neoplasm of the vascular endothelium [1,2,3]. It is an infrequent tumour, mostly secondary to an extrapulmonary primary angiosarcoma, being the primary pulmonary angiosarcoma a very rare entity [3,4,5].

Its clinical course is aggressive, with symptoms due to tumour erosion of blood vessels with haemoptysis, anaemia and coagulation disorders with increase of the D-dimer [3]. Other usual symptoms are cough, dyspnoea, chest pain and loss of weight [1,3,6].

The aetiology is unknown, although risk factors, such as exposition to vinyl chloride, have been described [1,7].

Imaging findings are variable and include lung nodules, which in more than 70% of the cases are multiples and bilateral; ground glass lung opacities, lung nodules with halo sign and infiltration of adjacent tissues [2,6,7].  

In the pulmonary angiosarcoma, the ground glass halo is due to haemorrhage secondary to the rupture of fragile abnormal vessel of the tumoural nodules, whereas, the central solid zone corresponds to the tumoural lesion itself [8].

The bronchoscopy is a nonspecific test because there are more frequent entities which show vessels proliferation like pulmonary arteriovenous malformations. Furthermore, in many cases not enough tissue is obtained for the histopathology analysis [4,9].

Definitive histopathology diagnosis is usually achieved after a surgical biopsy, as it was in our case. Histopathologically, pulmonary angiosarcomas are characterised by a proliferation of vascular channels covered by polygonal and ovoid neoplastic cells with atypical and irregular nucleus. Usually there are adjacent haemorrhagic foci [4,6].

Immunochemistry techniques show the endothelial origin of the tumour, with CD-31, CD-34 and factor VIII-related antigen positivity [1,2,3].   

When tumours are localised, these are treated by surgery and radiotherapy. However, due to the nonspecific respiratory symptoms and the rarity of this disease, a late diagnose is the rule. This, associated with the aggressive behaviour of the tumour, leads to the ominous prognosis of this entity [1,2,5].