Focal increased lung perfusion and intrapulmonary veno-arterial shunting in bronchiolo-alveolar cell carcinoma.

A patient with bronchiolo-alveolar cell carcinoma presented with a veno-arterial shunt localized to the area of tumor involvement by differential position shunt testing. Perfusion lung scan revealed increased radionucleotide uptake in the area of the tumor, confirmed by pulmonary angiography, and suggested that the primary blood supply to the tumor was originating from the pulmonary circulation. Surgical resection of the tumor resulted in marked reduction of the intrapulmonary shunt.