Generation of
thromboplastin by monocytes has been shown to play a vital role in hypercoagulable states seen in
malignancy. The purpose of this study was to compare the procoagulant activity in
cancer patients and controls. Recalcification times (RT) of whole blood from 19 normal volunteers, 8 patients with benign
polyps, 12 patients previously treated by surgery for head and neck (H&N) or
colon cancer, and 13 untreated patients with various stages of H&N or
colon cancer were determined. Tests were performed with and without stimulation with
Escherichia coli endotoxin. The mean RT in saline (RTS) of untreated patients with early
cancer (4.58 +/- 0.83 min) and that of patients with advanced
cancer (5.23 +/- 1.16 min) were lower than that of controls (6.55 +/- 0.82 min), P less than 0.01 and P less than 0.05, respectively. The RTS of patients previously treated and of those with benign
polyps were no different from those of controls. Activation with
endotoxin significantly lowered the recalcification times (RTE) in the early (3.90 +/- 0.58 min) and advanced
cancer patients (4.23 +/- 0.66 min) compared to the RTE of controls (5.69 +/- 0.75 min, P less than 0.01 for both groups) as well as compared to those with benign
tumors, P less than 0.05. The mean RTE of previously treated patients (4.72 +/- 0.58 min) was also lower than that of controls, P less than 0.05. Our results suggest that RT is significantly reduced in
cancer patients compared to that of controls. Furthermore, monocyte activation with
endotoxin may enable us to distinguish
cancer patients from controls as well as from those with benign
tumors.