Significance of pleural effusion in neuroblastoma

Pleural effusion is uncommon at diagnosis of neuroblastoma in children. Because the presence of malignant cells in pleural fluid may significantly change the management and outcome of patients with neuroblastoma, we retrospectively analyzed a cohort of neuroblastoma patients who presented with pleural effusion at the time of diagnosis to determine the incidence, presentation, stage, treatment, and outcome of these patients.

We reviewed the presenting features of 295 patients with the diagnosis of neuroblastoma who received treatment at St. Jude Children's Research Hospital between 1991 and 2005. Patients were chosen for further analysis if pleural effusion had been identified on chest radiographs or computed tomography (CT) scans at diagnosis

Thirty-one out of 295(10.5%) patients with neuroblastoma had pleural effusion identified at time of presentation. International neuroblastoma staging system (INSS) risk stratification was high risk in 29 cases and intermediate risk and low risk in 1 case each. The primary site of disease was abdomen in 26 patients; mediastinum in 5. We conducted cytologic analysis of pleural fluid of nine patients; the specimen of seven contained malignant cells. Eighteen of 31 patients died of progressive or recurrent disease.

In patients with neuroblastoma, pleural effusion is usually associated with unfavorable biologic features and high-risk disease. Pleural fluid should be examined cytologically and at a time when the results would change the risk stratification. There was no statistically significant difference in the survival rate of the patients with high-risk neuroblastoma with or without malignant pleural effusion.