Unusual intrathoracic complications in Wilms tumor.

Five children with intrathoracic metastases from Wilms tumor are presented. In two patients pneumothoraces developed, and in one patient pneumonitis developed secondary to a primary intrabronchial metastasis. Two other patients had paraspinal widening from metastases to paraaortic or posterior mediastinal lymph nodes. These are extremely rare complications of metastatic Wilms tumor.