CirculatingTumor Cells:Toward a clinical benefit?

Giuseppe Naso MD, PhD, Associated Professor of Medical Oncology Director of Traslational Oncology

Paola Gazzaniga, MD, PhD , University Researcher in Traslational Oncology

Sapienza Università di Roma

Metastatic Breast Cancer MBC is a heterogeneous condition

Treatment is palliative

Current clinical, laboratory, and radiological methods inadequate for

– Assessment of prognosis

– Definition of biology

– Measurement of efficacy/treatment benefit

Prognostic and Predictive Value of CTCs in MBC

Hypothesis Measurement of CTCs in MBC may:

– Identify aggressive disease (prognostic value)

– Provide early determination of treatment efficacy/benefit (predictive value)

Progression-Free Survival

Prob

abili

ty o

f Pr

ogre

ssio

n-Fr

ee S

urvi

val

Time From Baseline (Months)0 2 4 6 8 10 12 14 16 18 22 24 26 28 30

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20

Log rankP = .0001

7.0 months2.7

months

≥ 5 CTCs/7.5 mLn = 87 (49%)

< 5 CTCs/7.5 mLn = 90 (51%)

Cristofanilli M, et al. N Engl J Med. 2004;351:781-791.

Prognostic Value of Baseline CTC Counts

Overall Survival

Time From Baseline (Months)0 2 4 6 8 10 12 14 16 18 22 24 26 28 30

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20

Log rank P < .000121.9 months

10.9months

≥ 5 CTCs/7.5 mLn = 87 (49%)

< 5 CTCs/7.5 mLn = 90 (51%)

Cristofanilli M, et al. N Engl J Med. 2004;351:781-791.

Prognostic Value of Baseline CTC Counts

Prob

abili

ty o

f Pr

ogre

ssio

n-Fr

ee S

urvi

val

64%

43%

< 5 CTCsn = 90 (51%)

Cristofanilli M, et al. ASCO 2005. Abstract 524.

Probability of Death and Baseline CTC Counts

Time From Baseline (Months)0 2 4 6 8 10 12 14 16 18 22 24 26 28 30

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20

29%

≥ 5 CTCsn = 87 (49%)

53%

12%19%

Prob

abili

ty o

f Dea

th

Change in CTC Count During Therapy Predicts Overall Survival

Cristofanilli M, et al. ASCO 2005. Abstract 524.

4

1 vs 4 P < .0001

4 > 5 CTCs at all time points 39 (22%)

2

1 vs 2 P = .3188

2 vs 4 P < .0001

2 > 5 at baseline and < 5 CTC at last draw 38 (21%)

3

1 vs 3 P = .0014

3 vs 4 P = .0051

2 vs 3 P = .0397

3 < 5 at Early Draw and > 5 CTC at last draw 17 (10%)

Time From Baseline (Months)0 2 4 6 8 10 12 14 16 18 22 24 26 28 30

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20

1

1 <5 CTCs at all time points 83 (47%)

Prob

abili

ty o

f Sur

viva

l

CTC Significance in MBC: Prognostic and Predictive Values Prognosis — strongest independent factor

– In newly diagnosed disease (first-line treatment)

– Over the course of the disease (second-, third-, or higher-line treatment)

Prediction — predict treatment efficacy at 3-4 weeks

May represent a new standard of care

1.Una elevata conta delle CTC (>5/7.5 ml) è associata a ridotta sopravvivenza globale (10 vs 22 mesi)

e ridotto intervallo libero da malattia (2 vs 8 mesi)

2. La conta delle CTC è fattore prognostico più affidabile delle indagini radiologiche e dello stato recettoriale nei k mammari

3. 1/3 delle pazienti con k mammario HER-2 negativo hanno CTC HER-2 positive

1. La risposta alla terapia adiuvante è associata ad una riduzione del numero di CTC

2. La presenza di CTC 4 settimane dopo la chirurgia correla con un ridotto intervallo libero da malattia e con ridotta sopravvivenza globale

Human equilibrative nucleoside transporter 1Deoxycytidine kinase (dCK)

CK8

Spiked MCF7 cells in 10 ml of blood

PRIMER SEQUENCE 5’→3’ Annealing(t°C)

SIZEbp

GAPDH upstream ACATGTTCCAATATGATTCC 60 161

downstream TGGACTCCACGACGTACTCAG

CD 45 upstream CAGCGCTTCCAGAAGGGCTC 60

downstream CCGTGCAGCTCTACGAGAGG

CK-8

upstream ACTGAGATCTCAGAGATCAA

60downstream AATACTCATGTTCTGCATCC

MRP 1 upstream CTGACAAGCTAGACCATGAATGT 60 353

downstream TCACACCAAGCCGGCGTCTTT

MRP 2 upstream GTGATGGTGCTTGTAATCCCA 60 277

downstream TGACCACAGATACCAGGACTG

MRP 4 upstream GGATCCAAGAACTGATGAGTTAAT 65 358

downstream TCACAGTGCTGTCTCGAAAATAG

MRP 5

upstream CTAGAGAGACTGTGGCAAGAAGAGC 68 332

downstream AAATGCCATGGTTAGGATGGC

MRP 7 upstream TAGGCACTGACTCTGAACGG 60 160

Downstream TTGTTGACGGGTACCAGCAG

dCK upstream TGCAGGGAAGTCAACATT 52 146

downstream TCCCACCATTTTTCTGAG

hENT 1 upstream GCTTGAAGGACCCGGGGAGC 67 502

downstream TGGAGAAGGCAAAGGCAGCCA

Sensibilità:bassa espressione MRP

Elevata espressione hENT/dCK

Resistenza:elevata espressione MRP

Bassa espressione hENT/dCK