Introduction
The fact that cancer cells can be identified in the blood stream of patients with malignant disease has been well documented,1-6 but their isolation and identification is somewhat complicated. Although a number of methods of separation have been reported, all of these methods, including that originally used in our laboratory,3 seem to us to be either cumbersome or not practical. Accordingly, we recently developed a simplified technique,7 modifying the streptolysin method originally reported by Malmgren et al.8 This study compares the results of this simplified isolation technique with several other methods, and amplifies the possible role of surgical manipulation and operative stress in the vascular dissemination of cancer cells.
Collection of Samples
Blood samples were collected from a number of sites, but in this series primarily from a peripheral vein (antecubital). In several instances samples were obtained from the vena cava via a polyethylene catheter