A rare tumor masquerading as an empyema: pleuropulmonary blastoma

Paediatric thoracic tumours presenting as empyema

Ultrasonography (US) is considered to be adequate for the preoperative evaluation of childhood empyema. This study was aimed to improve awareness that paediatric intra-thoracic tumours can mimic childhood post-pneumonic empyema and highlights the value of computed tomogram (CT) scan with intravenous (IV) contrast in preoperative evaluation of childhood empyema. The data were analysed on eight children (four boys and four girls) presented at the median age of 6.2 years (1.8-15 years) for the management of empyema and later confirmed to have intra-thoracic tumours. Intra-thoracic tumours in 8 (5.3%) children out of 150 cases of post-pneumonic empyema were managed during the study period. All eight had clinical features, increased white cell count, raised inflammatory markers and biochemical parameters suggestive of childhood empyema. Chest X-ray showed localised opacity in 3/8 while in other five suggested significant pleural collection with mediastinal shift. Additional investigations in referring hospital were suggestive of empyema in four children; US in three, CT scan without IV contrast in one. Referring hospital carried out non-diagnostic thoracocentesis in four children with blood stained pleural tap in two. In four children corroborative evidence suggestive of infection within pleural cavity and acute respiratory distress led to an emergency mini-thoracotomy resulting in significant intra-operative bleeding in two children. Histology on biopsy of the infected material showed primitive neuroectodermal tumour (PNET) in one, pleuropulmonary blastoma in one, metastatic malignant melanoma in one and cytology of pleural fluid diagnosed lymphoma in one. Pre-operative CT scan with IV contrast in four children correctly identified underlying intra-thoracic tumour (two benign teratoma, two PNET). In two cases CT with IV contrast was performed because chest X-ray suggested mediastinal loculated empyema while in other two high clinical index of suspicion prompted preoperative evaluation with CT scan with IV contrast. We advocate caution and increased awareness before considering therapeutic options in childhood empyema and recommend preoperative CT scan with IV contrast in some selected and unusual cases.

Case report: pulmonary blastoma: presentation of two atypical cases and review of the literature

Pulmonary blastoma is a relatively rare aggressive adult malignancy. The clinical and radiographic features of two cases are described and the literature reviewed. Pulmonary blastoma usually presents radiologically as a well-defined mass lesion on chest radiography, which may be large enough to completely opacify the hemithorax and cause mediastinal shift. On CT, pulmonary blastoma is seen as a mixed solid and cystic lesion with variable contrast enhancement and a necrotic centre. Pleural effusion may be present but is not the predominant abnormality. Our cases are unusual as recurrent pleural effusions in the absence of a significant lung mass were the presenting findings.

Critical presentation of pleuropulmonary blastoma

We report two cases of critical presentation of a quite rare lung neoplasm of childhood. Presentation findings were at the extremes of the clinical pattern of this polymorphous neoplasm, ranging from an enormous solid mass causing airway compression and dislocation to an apparently benign cystic lesion discovered because of a tension pneumothorax. Both children were discharged from the pediatric intensive care unit and underwent appropriate surgical removal and oncological management. Congenital lung cysts, even asymptomatic, should not be underestimated and need elective surgical excision and histologic examination.

[Pleurisy: diagnostic and therapeutic management]

Diagnosis of pleural effusion is difficult in children. The etiologies are numerous; however, infectious agents are more frequent. Thoracocentesis proves to be the first-line diagnostic tool. Light's criteria are the best for distinguishing whether the effusion is a transudate or an exudate. If the patient has an exudative pleural effusion, other tests are indicated to determine the etiology and in some cases the treatment: macroscopic appearance, cytology and differential white cell count (level of glucose, lactate dehydrogenase, adenosine deaminase, pH, bacterial cultures). Others investigations--biopsy of pleura by thoracoscopy or video-assisted thoracoscopy, bronchofibroscopy, CT scan--are sometimes useful. Intrapleural instillation of urokinase appears to be useful and safe. Evaluation is necessary for video-assisted thoracoscopy used early.