Pulmonary epithelioid haemangioendothelioma - pardon me doctor, but what is that rare mass on my lung?

Clinical History

A 64-year-old female patient presented to our emergency department with progressive cough, asthenia and thoracic pain. On work-up, the WBC count was normal, but the patient had anaemia. Regarding her background, she had a history of hypertension, thyroid nodules, gastritis and was obese.

Imaging Findings

The patient was admitted for further studies and underwent chest radiography (Fig. 1 a, b) and thoracic CT, which revealed a 7 cm mass in the left lower lobe, extending from the left hilum to the pleura, invading the mediastinum, compressing the pulmonary vessels and bronchi, as well as the left atrium (Fig. 3 a, b, c). This soft tissue mass had no calcifications and demonstrated heterogeneous enhancement. Regarding the remainder of the lung parenchyma, there were also patchy left lower lobe consolidations, all of which had resolved on follow-up examination (Fig. 2). In the upper abdominal scan, there was a 3 cm mass in the left adrenal gland, compatible with metastasis (Fig. 3 e). The patient underwent fiberoptic bronchoscopy with lavage, which was negative for malignant cells. Therefore she subsequently underwent surgical biopsy.

Discussion

We report a rare case of a 64-year old female patient with pulmonary epithelioid haemangioendothelioma (PEH) demonstrating dramatic therapeutic response.
PEH is a rare neoplasm which originates from the vascular endothelium of large veins [1, 2]. This tumour was initially considered a variant of bronchogenic carcinoma, but is now recognized as a separate entity, namely the pulmonary counterpart of epithelioid haemangioendothelioma, with low to intermediate grade malignancy. There are scarce reports in the literature and its pathogenesis is unclear. Most cases have been reported in female patients with an age presentation ranging from 12-60 years [2]. Clinically, most patients present with dry cough, dyspnoea, pleuritic pain and rarely haemoptysis, although some may remain completely asymptomatic. On imaging, the typical pattern is characterized by multiple perivascular nodules with well or ill-defined borders, ranging from 3 mm to 3 cm, some of which can have calcification [3]. Atypical patterns include the presence of a large solitary mass, mimicking a bronchogenic carcinoma. Pleural effusion and metastases are rarely seen [1]. Diagnosis is established with immunohistochemical analysis, with positivity for vascular markers such as factor VIII, CD31, CD34 and von Willebrand's antigen [1, 2]. In terms of prognosis and considering the scarce literature reports, it seems to be variable, with a 5-year survival rate estimated at about 60% [1]. There are some indicators of poor prognosis, such as large masses (>3cm), pleural effusion and distant metastases on presentation [2]. Treatment is yet to be standardized, with surgical resection considered in case of solitary nodules or unilateral multiple nodules. Some authors suggest that an increased 18-FDG uptake by the nodules raises suspicion of a malignant lesion and should be regarded as a surgical indication [3]. Chemotherapy is considered the treatment of choice for unresectable or metastatic disease and the results are variable. Our patient underwent a 6-month regimen with etoposide and carboplatin, demonstrating marked regression in lesion size. Other therapeutic options include IFN, anti-oestrogens and progesterone, all of which lead to slight regression in lesion size [2].

Differential Diagnosis List

Final Diagnosis

Pulmonary epithelioid haemangioendothelioma of the left lower lobe with mediastinal involvement and adrenal metastasis

URL:	https://www.eurorad.org/case/12127
DOI:	10.1594/EURORAD/CASE.12127
ISSN:	1563-4086