In summary, on the basis of either flow-cytometric or molecular analysis, we demonstrated that 44 of 45 patients with CLL (98%; 95% confidence interval [CI], 88 to 100) had a prediagnostic B-cell clone. In particular, 41 patients (91%; 95% CI, 79 to 98) had a prediagnostic clone detected by both techniques, whereas 2 patients (Patients 27 and 30) (4%) had evidence of a prediagnostic clone only on RT-PCR analysis, and 1 patient (Patient 8) (2%) had evidence of a prediagnostic clone only on six-color flow cytometry. One patient (Patient 6) had negative results on the basis of both methods; all 10 control subjects also had negative results.
