Progress in Using Circulating Tumor Cell Information to Improve Metastatic Breast Cancer Therapy
Figure 1
Algorithms for incorporating CTC measurements into clinical decision making. (a) Beveridge algorithm [18] for management of metastatic breast cancer using circulating tumor cell information. (b) An updated algorithm incorporating CTC information in the monitoring strategy. Additional time may be added before a second CTC assessment for patients starting new systemic therapy for CTC counts to stabilize. Declining CTC counts suggest treatment response but require confirmation subsequently. The interval between follow-up CTC counts considers clinical behavior of the tumor. ‡Clinical assessment may include imaging studies, physical examination, histology, CTC enumeration, and serum tumor marker determination. *Disease status may be monitored using CTC counts every 1–3 months, with imaging studies performed if clinical evidence of progression is observed. †Repeat CTC assessment after an additional 1-2 cycles of therapy to verify that CTC counts are <5 per 7.5 mL; CTC counts that remain ≥5 upon retesting suggest treatment failure.
