Latent pulmonary embolus from a retroperitoneal sarcoma.

A 52-year-old female presented with an extensive retroperitoneal sarcoma and intraluminal inferior vena caval extension. Presumably during resection, embolization of a tumor fragment occurred to the right pulmonary hilum. The patient was asymptomatic for 16 months until a right hilar mass developed on a follow-up chest x-ray. Pathological examination of the gross and microscopic sections of the pneumonectomy specimen confirmed the intra-arterial location of the tumor mass. Widespread systemic metastasis became evident soon after pneumonectomy.