Flow of patients through the study. Of 403 consecutive patients assessed for eligibility, 10 (2.5%) were excluded from the study because essential data items were not available (no clinical data: 1 patient; no CTCBL data: 9 patients). Of the 393 patients included in the study, 192 had no CTC1C counts and were therefore excluded from further analysis for the following reasons. During the initial phase of the study, i.e. the first 100 patients, CTC1C status was routinely determined only in CTCBL+ patients, resulting in 64 CTC1C- patients without CTC1C counts. Of the remaining 128 patients without CTC1C counts, 12 were excluded because blood samples were not obtained within the predefined study timeframe of 0.5–3.2 months, 25 did not survive to CTC1C assessment because they died within the first 3.2 months, and 91 patients who survived beyond 3.2 months after inclusion had no CTC1C count (41 had not yet proceeded to CTC1C and 50 were lost to follow-up blood sampling as our center often treats external patients).