Schematic picture of 10 cancer patients with warfarin-associated venous limb ischemia. For 11 different clinical or laboratory features, labeled “A” through “K”, the number of patients illustrating that feature (numerator) among evaluable patients (denominator) is shown at the bottom of the figure. Note that for 8 of 10 patients (B), a diagnosis of cancer was not known or suspected at the time the patient presented with DVT. The reasons why the denominator is <10 for some features is as follows: (E and G) platelet count measurements not available (eg, outpatient treatment); (I and J) plasma samples not available (note that whereas plasma samples from 6 available patients showed elevated TAT levels, samples from only 4 patients were available from the time of onset of venous limb ischemia/gangrene; however, 4/4 patients showed PC activity levels ≤0.10 U/mL).