Transcatheter brush biopsy of intravenous tumor thrombi.

Transcatheter brush biopsy of intraluminal filling defects demonstrated during venography was performed in 6 patients with abdominal neoplasms. Tissue specimens consistent with either known or subsequently proved tumor were obtained from 4 patients. Biopsy was negative in the other 2 patients, who lacked surgical confirmation of the intraluminal mass. This technique is useful in establishing histological proof of neoplasm and in determining the extent of known tumor.