Pneumoblastoma in an adult

Histology revealed a diagnosis of pneumoblastoma. Additional imaging work-up was negative (brain CT, bone scintigraphy, abdominal ultrasound). The patient was treated with chemotherapy with moderate results (Fig. 5).

Clinical presentation is varied: mostly, the tumour is asymptomatic for a long time [2]; cough and dyspnoea appear with large tumours. A case of spontaneous pneumothorax has been reported [3].

Imaging is non-specific. On conventional radiographs pneumoblastoma appears as a large peripheral mass [2]. Most of the time CT shows a heterogeneous parenchymal mass, with contrast enhancement. Large tumours contain low density areas corresponding to necrosis. Calcifications are possible [2].

All kinds of secondary visceral localisations are found, mostly in the liver and brain [2]. Metastases to lymph nodes (in the neck and mediastinum), bone, pancreas and adrenal glands have been described [2].

Vascular extension, as described in this case, is less frequent: only two cases of vascular extension have been described in the literature [4-5], and one case concerns an extension into the left atrium through a pulmonary vein.

Definite diagnosis of the pneumoblastoma is histological - the presence of cells with blastematous character, very similar to foetal lung, is characteristic - and it is necessary to differentiate pneumoblatoma from carcinoma [1].