Pivotal Clinical Trial—Circulating tumor cells (CTCs) as a predictive marker of tumor response, progression-free survival, and overall survival (OS) in patients with mCRC1,2
Trial design
CTCs were monitored in 430 mCRC patients at baseline and after starting 1st, 2nd, or 3rd line therapy.1
Results
Case Study
57-year-old male patient with mCRC with liver metastases
Stephan Cohen, MD, Associate Medical Director, Fox Chase Cancer Partners, Philadelphia, PA
Patient history and response to treatment
Imaging in patient with mCRC showed >10 metastatic lesions in the liver
Baseline circulating tumor cells (CTCs) were 7; baseline carcinoembryonic antigen (CEA) was 12 U/mL
Patient was initiated on aggressive chemotherapy
Within a month, the patient’s CTCs dropped to 2, indicating a favorable prognosis
Three months later, CTCs remained low and imaging confirmed stable disease SD
At that time, patient had developed grade 2 neuropathy—based on favorable CTC and imaging results, the patient began a less aggressive treatment regimen
Thereafter, CTCs were monitored regularly; when the number of cells rose above cutoff, imaging was performed to obtain a complete picture of the patient's clinical status and inform clinical decisions
The clinical cutoff of CTCs per 7.5 mL of blood for patient with mCRC is ≥3.
How CTCs helped inform the management of this patient
Results of the CELLSEARCH® CTC Test confirmed imaging and predicted poor prognosis. After aggressive chemotherapy was initiated, CTC monitoring was used to track the patient’s status and indicated SD for 6 months.
When the patient developed grade 2 neuropathy, low CTCs indicating favorable prognosis and SD by imaging helped in the decision-making process to initiate a less toxic regimen.
Thereafter, serial CTCs were measured and imaging studies were performed when CTCs rose above the cut-off, which, for this patient, necessitated fewer overall radiological tests. CTCs, in conjunction with imaging, helped in the clinical management of this patient.
“With the CTC count remaining low when it had been previously elevated and imaging study showing stable disease, I felt comfortable continuing a less intensive regimen when neuropathy developed." — Stephan Cohen, MD
CELLSEARCH® CTC Test results should be used in conjunction with all clinical information derived from diagnostic tests (eg, imaging or laboratory tests), physical examination and complete medical history, in accordance with appropriate management procedures.
This case study is for educational purposes only and does not constitute professional medical advice. The information provided in this case study should not be relied upon as the basis for making patient management decisions. This case study is not intended to show that any line of therapy is any more or less effective than any other or no therapy. Please see instructions for use for indications and limitations of the CELLSEARCH® CTC Test as a monitoring aid in management of metastatic breast, colorectal, and prostate cancer.
References:
Cohen SJ, Punt CJA, Iannotti N, et al. J Clin Oncol. 2008;26(19):3213-3221.
CELLSEARCH® Circulating Tumor Cell Kit (Epithelial) Instructions for Use. Menarini Silicon Biosystems Inc.
