Director of Precision Oncology & Research, Asian Institute of Oncology,

Sion, Mumbai

Dr Purvish M ParikhMD, DNB, FICP, PhD, ECMO, CPI, MBA

purvish1@gmail.com

Circulating Tumor Cells

9th SAARC Federation of Oncologists’ Conference

Circulating Tumor Cells (CTC)

• Cristofanilli M et al: CTC, disease progression, and survival in MBC. NEJM 2004; 351: 781-791

• Google search - 9,11,000 hits • Medline Search – 15,272 publications

706 so far in 2014

• Kim H et al: Development of On-Chip Multi-Imaging Flow Cytometry for Identification of Imaging Biomarkers of Clustered CTC. PLoS One. 2014 Aug 20;9(8):e104372.

Circulating Tumor Cells – Liquid biopsy

Assay uses 15 ml peripheral whole blood for CTC of epithelial origin for: – detection, – enrichment and – quantification .

1. Predict progression free survival (PFS) and overall survival (OS)

2. Monitor response to therapy

CTC – Concept

CTC - identification

• Nucleated cells (DAPI+)

• Expressing CK (cytokeratin) in cytoplasm, and EpCAM (epithelial cell adhesion molecule) on cell surface

• Using immunofluorescent reagents.

CTC images courtesy : Datar Genetics, Mumbai, India

CTC - identification

Green – cytokeratin (CK)

Red – EpCAMBlue – DAPI (Nucleus)

Composite staining showing all three features

CTC images courtesy : Datar Genetics, Mumbai, India

CTC – cut off levels

5 CTCs/7.5 mL blood: • Metastatic breast cancer• Metastatic prostate cancer

3 CTCs/7.5 mL blood: • Metastatic colorectal cancer

CTC – Predictive Value

Favourable CTC Unfavourable CTC

Breast CaPFS 7.0 2.7

OS 21.9 10.9

CRCPFS 7.9 4.5

OS 18.5 9.4

Prostate CaPFS 5.8 4.2

OS 21.7 11.5

CTC – Monitoring Rx efficacy

• Predict treatment response earlier (3-4 weeks) than imaging (8-12 weeks) after initiation of therapy.

• Accurate indicator of rapid disease progression and shorter survival.

CTC – additional application

• Captured CTCs can be used for molecular profiling studies (DNA, RNA) including FISH, array based methodologies, and cellular phenotyping (PSA, HER-2/neu or EGFR )

• Also has application in cancers of urinary bladder, biliary duct, liver, pancreas and lung.

CTC – quantitative vital cells

CTC – in vitro chemosensitivity (1)

CTC – in vitro chemosensitivity (2)

Baseline 3 hrs 6 hrs 9 hrs Baseline 3 hrs 6 hrs 9 hrsDrug

-vecontrol

Carbo-platin

Cisplatin

Adria-mycin

Cape-citabine

Drug

Paclitaxel

Docetaxel

Epirubicin

Cyclophosphamide

5 FU

Results within 9 hours

Role of Molecular Testing

Exists at every stage of the cancer• Correct diagnosis• Prognostic and predictive value • Selecting

– Most effective drug / combination – High risk patients for additional Rx– Early detection of recurrence – Preventing unwanted drug toxicity

• Screening - family history of cancer

Remember ….. Teamwork

is everything