Pulmonary sulcus metastases simulating intraabdominal malignancy in childhood tumors

Wilms tumor, the most common solid childhood malignancy, is frequently associated with pulmonary metastases, while hepatic metastases occur less frequently. Metastases to the lower lobes of the lungs, when deep in the costophrenic sulcus, may simulate an intraabdominal mass. The differentiation of these lesions is important both diagnostically and therapeutically. Three cases are presented in whom pulmonary sulcus metastases simulated abdominal lesions on computed tomography and could not be clearly localized as thoracic in origin on liver/spleen scintigraphy. Ultrasound evaluation was the most useful; however, integration with other imaging techniques was necessary to correctly identify these lesions as being of pulmonary origin.