Prognostic significance of circulating tumor cell (CTC) levels at various times during first- and second-line chemotherapy for metastatic breast cancer (MBC).

• DOI: 10.1200/jco.2012.30.15_suppl.e21077
• Publication Date: 2020-03-11T19:25:38Z
• Authors: Rafael Arteta-Bulos; Paul J. E. Miller; Rebecca S. Overbury; Alison Schwartzberg; Mark S. Walker; Lee Steven Schwar...
• Keywords: Circulating tumor cell; Progression-free survival

e21077 Background: CTCs have prognostic capability in the treatment of MBC based on a dichotomous level ≥5/7.5 ml blood (Hi) vs. <5/7.5 (Lo) at baseline and first follow-up. The value beyond is not well established, implication values that are reduced but remain high has been explored. Methods: Chart review patients (pts) 1 st or 2 nd line MBC, with CTC determinations between 2/2008 9/2011, were retrospectively identified large community oncology practice. Pts ≥2 ≥5 eligible. Demographics, regimens progression-free survival (PFS) assessed. Veridex Cell Search system was utilized for all determinations. Qualifying those drawn -14 days to +30 from start treatment. Results: 221 eligible pts identified, 71 line, 84 line. Median age 59.5 (range 26-90), 40.7% African-American, 17.6% HER2+, 63%/49% ER/PR+. median time 5 day PFS 8.0 5.8 mo among Hi Lo groups (p = 0.085). 3.7 4.0 groups, respectively, (ns). Follow-up obtained clinical convenience. A 90 landmark used analysis by four baseline/follow-up pattern groups. showed medians ranging 6.0 (Hi/Hi) 10.2 (Lo/Lo). In (n=24), 7.0 follow-up .64). Grouping reductions absolute count (<33% ≥33%) 3.5 <33% reduction, 8.8 ≥33% reduction .0179). Sensitivity analyses other cutoffs 20-80% similar results. Conclusions: setting, subsequent various times after yield clinically useful information. positive levels experiencing exhibit significantly longer PFS, indicating simple high/low approach test can be modified more value.