Clinical value of circulating tumor cells in metastatic breast cancer
1. Clinical value of CTCs in metastatic Breast Cancer
N. Xenidis, Democritus University of Thrace
4. What we can do ?
Systemic therapy
Against ?
Metastatic Breast Cancer Cells
Based on what ?.
5. ? Are all metastatic sites
composed of the same
cell population,
identical to primary
tumor population ?.
Based on primary tumor characteristics Is this right ?
1st line
Chemo
6. Krøigard A. Breast J. 2016 Jul;22(4):420-30
Molecular Concordance Between Primary Breast Cancer
and Matched Metastases
Probably not
There are many reports about discordance of hormone receptors
expression between primary tumors and metastatic lesions
.
8. Moreover
various factors, such as
- microenvironment
- epigenetics
- chemotherapy
- ……
lead to a higher genotype
and phenotype diversity
Different metastatic clones
differ in their ability to colonize specific organs
…and probably every
metastatic lesion harbors
more than one
cellular population.
10. What we can do ?
Repeated biopsies in
every new lesion ?
invasive
time spending
costly
…….
11. Even if…
Focus 1 Focus 2
Necrosis Inflammatory cells
Obtained information depends
on the point of biopsy.
12. samples obtained from primary renal
carcinomas and associated metastatic sites.
Gerlinger M. N Engl J Med. 2012
Intratumor Heterogeneity and Branched Evolution
Revealed by Multiregion Sequencing
13. Gerlinger M. N Engl J Med. 2012
Intratumor Heterogeneity and Branched Evolution
Revealed by Multiregion Sequencing
128 mutations
40 ubiquitous mutations
31 mutations shared by primary tumor regions
28 mutations shared by metastatic regions
29 mutations that were unique to specific regions (private mutations)
more branched than linear evolution.
14. Anderberg C. J Exp Med. 2013 210(3)
Deficiency for endoglin in tumor vasculature weakens the
endothelial barrier to metastatic dissemination
‘Gaps’ on immature and abnormal
tumor vessels permit thousands
tumor cells to reach bloodstream
every day.
16. cell-free DNA represents the
genomic DNA fragments
released from all tumor sites,
from viable and apoptotic
cells
Apart from circulating tumor cells (CTCs),
from peripheral blood can be isolated
various components of the tumor, such as
circulating cell-free DNA (ccfDNA) or exosomes
(cell-derived vesicles)
In contrast, circulating tumor
cells are clearly related to the
disease process, predict more
aggressive disease and
increased metastasis.
As such, CTC reflect the
dynamic and metastatic
subset of tumor cells.
18. Clinical validity of circulating tumor cells
in patients with metastatic breast cancer
19. Cristofanilli M, N Engl J Med 351;8 19, 2004
Circulating Tumor Cells, Disease Progression,
and Survival in Metastatic Breast Cancer
Patients with more than 5 CTCs per
7.5ml of whole blood before the
treatment had a shorter median PFS
and shorter OS
The multivariate Cox proportional-hazards regression
showed that, the levels of CTCs at baseline were the
most significant predictors of progression-free and
overall survival.
What is prognostic impact of CTCs detection
in Metastatic BC patients ?
20. 1944 patients with MBC from 20 studies
CTC count >5/7.5 mL
at baseline associated
with decreased PFS
(HR 1.92, p<0.0001)
and overall survival
(HR 2.78, p<0.0001).
Bidard FC, Lancet Oncol. 2014 Apr;15(4):406-14
Clinical validity of circulating tumour cells in patients with
metastatic breast cancer: a pooled analysis of individual patient data
21. Banys-Paluchowski M, Front. Oncol., 01 December 2016
Potential Role of Circulating Tumor Cell Detection and Monitoring in Breast
Cancer: A Review of Current evidence
Detection and count of CTCs in patients with metastatic BC
significantly correlates with disease-free survival and overall survival
22. Daniel L Adams, Breast Cancer Res. 2016; 18: 44
Mitosis in circulating tumor cells stratifies
highly aggressive breast carcinomas
36 women with stage III or stage IV breast cancer
Aim: evaluation of prognostic value of the mitotic status of CTCs
Patients without mitotic CTCs had a median
survival >24 mo, whereas patients with ≥1 mitotic
events had a median survival of 5.7 mo
hazard ratio 11.1.
Does all collected CTCs have the same importance ?
23. Giuliano M, Breast Cancer Research 2014, 16:440
Circulating tumor cells as early predictors of metastatic spread
in breast cancer patients with limited metastatic dissemination
Peripheral blood from 492 women with MBC collected within 30 days before starting any systemic treatment
Aim: correlation between CTCs count before therapy and type of disease progression (‘local’ or expanded)
Development
of new metastatic
sites was
significantly more
frequent among
patients with
≥5 CTCs compared
to those with
<5 CTCs
(progression of pre-
existing lesions)
186 patients without visceral metastasis
Development
of visceral
metastases was
significantly
more frequent
in the group
with ≥5 CTCs.
can CTCs count predict the severity
of the upcoming progression ?
24. Giuliano M, Breast Cancer Research 2014, 16:440
Circulating tumor cells as early predictors of metastatic spread
in breast cancer patients with limited metastatic dissemination
time to the development of visceral disease was remarkably different between the CTC groups
(42.1 months versus 15.9 months in women with <5 CTCs/7.5 ml versus ≥5 CTCs)
Pretreatment CTC counts may identify in advance patients who have higher risk of developing widespread visceral
disease and consequently might benefit from early administration of more aggressive systemic treatments.
Also useful in patients with limited metastatic dissemination and potentially eligible for locoregional
treatments with a curative intent.
26. Hayes DF, Clin Cancer Res. 2006 Jul 15;12
Circulating tumor cells at each follow-up time point during therapy of
metastatic breast cancer patients predict progression-free and overall survival.
Detection of elevated CTCs at any time during therapy is an accurate indication of subsequent rapid
disease progression and mortality for MBC patients.
What about the effectiveness of therapy on CTCs ?
(fluctuation of CTCs count during therapy)
27. Bidard FC, Lancet Oncol. 2014 Apr;15(4):406-14
Clinical validity of circulating tumour cells in patients with
metastatic breast cancer: a pooled analysis of individual patient data
Increased CTC counts 3-5 weeks
after start of treatment, adjusted
for CTC count at baseline, were
associated with shortened
progression-free survival
(HR 1.85, p<0.0001)
and overall survival
(HR 2.26, p<0.0001)
28. 50 studies with 6712 patients, neoadjuvant, adjuvant & metastatic
Reduction of CTC-positive rate was associated with
- lower probability of disease progression (OR = 0.54, P = 0.01)
- longer progression-free survival period (mean difference = 5.07 months, P < 0.0001)
- longer overall survival period (mean difference = 11.61 months, P < 0.00001)
These results demonstrate that CTC status can serve as an indicator to monitor the effectiveness of treatments.
Wen-Ting Yan, Nature Scientific Reports 2017, 7:43464
Circulating tumor cell status monitors the treatment responses
in breast cancer patients: a meta-analysis
29. Budd T, Clin Cancer Res. 2006 Nov 1;12(21)
Circulating Tumor Cells versus Imaging
Predicting Overall Survival in Metastatic Breast Cancer
<5 CTCs and stable disease/partial response by radiology
<5 CTCs and progressive disease by radiology
≥5 CTCs and stable disease/partial response by radiology
≥5 CTCs and progressive disease by radiology
138 metastatic breast cancer patients
Use of CTCs Vs radiology for prediction of overall survival
Multivariate Cox proportional hazards
regression, hazard ratios:
- 2.00 (P = 0.006) radiology assessment
- 2.53 (P < 0.001) for CTCs.
Radiology assessment is not enough ?
Assessment of CTCs is an earlier, more
reproducible indication of disease
status than current imaging methods.
CTCs may be a superior surrogate end
point, as they are highly reproducible
and correlate better with overall
survival than do changes determined
by traditional radiology.
30. Smerage J, JCO 2014
Circulating Tumor Cells and Response to Chemotherapy in
Metastatic Breast Cancer: SWOG S0500
Is this information
(impact of therapy
on CTCs count) adequate
for treatment guidance ?
Did early discontinuation of
an ineffective treatment
(in terms of CTCs elimination)
and switch to an alternate
therapy improves outcome ?.
31. For patients with persistently increased CTCs after 21 days of first-line
chemotherapy, early switching to an alternate cytotoxic therapy
was not effective in prolonging PFS or OS
Smerage J, JCO 2014
Circulating Tumor Cells and Response to Chemotherapy in
Metastatic Breast Cancer: SWOG S0500
33. Aktas B, Gynecol Oncol. 2011;122(2):356–60
Comparison of estrogen and progesterone receptor status of circulating
tumor cells and the primary tumor in metastatic breast cancer patients
Overall detection rate for CTCs was 45% (87/193 patients)
77% patients with ER(+) tumors, have ER(-) CTCs
87% patients with PR(+) tumors have PR(-) CTCs
Primary tumors and CTCs displayed a concordant ER and PR
status in only 41% and 45% of cases, respectively.
Loss of hormonal receptor expression during the course of the disease is considered
as a cause for poor response to endocrine therapy in primarily hormonal
receptor-positive breast cancer patients.
Reassessment of ER and RP in CTCs and in recurrent tumor samples could guide
treatment decisions in metastatic treatments.
Re-assessment of therapy targets
How molecular characterization of CTCs
can improve management of patients with MBC ?
34. Re-assessment of hormone receptor status…
Is adequate ?
One half of patients with HR(+)
metastatic breast cancer does not respond
in hormone depletion
Paoletti B, San Antonio Breast Cancer Symposium 2016
Circulating tumor cell number and CTC-endocrine therapy index predict clinical outcomes in ER positive
metastatic breast cancer patients: Results of the COMETI Phase 2 trial
CTC expression of 4 markers:
- low expression of ER and BCL-2,
- high expression of HER2 and Ki67
as markers of endocrine therapy resistance
(CTC-Endocrine Therapy Index, CTC-ETI)
80% of patients with high CTC-ETI experienced rapid
progression vs 40% of patients with low CTC-ETI
.
35. Shaw J, Clin Cancer Res. 2017 Jan 1;23(1):88-96
Mutation Analysis of Cell-Free DNA and Single Circulating Tumor Cells in Metastatic
Breast Cancer Patients with High Circulating Tumor Cell Counts
CTCs were isolated by DEPArray and compared with matched cfDNA and primary tumor tissue by
targeted next-generation sequencing (NGS) of about 2,200 COSMIC mutations in 50 cancer genes
NGS analysis of CTCs from 5 patients with MBC revealed mutational heterogeneity in PIK3CA, TP53, ESR1, and KRAS
genes between individual CTCs. ESR1 and KRAS gene mutations were absent from primary tumor tissue
The ESR1 p.D538G, p.Y537
mutations leads to ligand-
independent activation of
ERa and in primary resistance
to endocrine therapy.
what about ESR1 mutations ?
36. But,
almost all patients, after an initial
response, eventually become resistance
in endocrine therapy…
PI3K-activating mutations
can activate AKT-ER pathway
in the absence of estrogen
and may this way contribute
to resistance to endocrine
therapy.
37. Guttery D, Clin Chem. 2015 Jul;61(7)
Next Generation Sequencing (NGS)
for detection of hot-spot mutations
in ESR1, PIK3CA, TP53, FGFR1 & 2
PIK3CA p.E545K mutation
emerged 4 months into the study,
and the mutation frequency
increased through treatment and
correlated with the clinical course
of the disease as assessed using
the serum marker CA15-3
Mutation Analysis of Cell-Free DNA and Single Circulating
Tumor Cells in Metastatic Breast Cancer Patients with High
Circulating Tumor Cell Counts
Analysis of serial samples collected in patients while on therapy
Suppression of AKT pathway with
pan-PI3K inhibitors (burpalisib-BELLE-2 trial),
and mTOR inhibitors (everolimus-BOLERO-3 trial)
probably overcomes acquired resistance.
38. BELLE-2: Phase III, randomized, placebo-controlled study of buparlisib with fulvestrant in postmenopausal
women with HR(+)/HER2(-) advanced breast cancer progressing on or after an aromatase inhibitor
Baselga J, SABCS 2015 S6
Study met the primary endpoint: addition of Buparlisib to Fulvestrant improves PFS
.
39. ctDNA from 587 patients was analyzed for
PIK3CA mutations by BEAMing technology
In a group of pts with PI3KCA mutations identified by
ctDNA during liquid biopsy, the overall response rate
with fulvestrant and buparlisib was 18.4%, compared
with 3.5% with fulvestrant and placebo (Δ: 14.9%).
In a group of pts with PI3K activation in archival
tissue (primary tumor) the overall response rate with
fulvestrant and buparlisib was 10.6%, compared with
8.2% with fulvestrant and placebo (Δ: 2.4%)
BELLE-2: Phase III, randomized, placebo-controlled study
of buparlisib with fulvestrant in postmenopausal women
with HR+/HER2[ndash] advanced breast cancer
progressing on or after an aromatase inhibitor
Baselga J, SABCS 2015 S6
40. Current molecular profile of the disease can predicts accurately the response in a certain therapeutical intervention
Comparison of the PI3KCA pathway in circulating tumor cells and corresponding tumor tissue of patients
with metastatic breast cancer
Bredemeier M, Mol Med Rep. 2017 May;15(5):2957-2968
90 metastatic BC patients
41% (25/61) of patients with PI3KCA wild-type tumors had PI3KCA(+) CTCs
55% (16/29) of patients with PI3KCA mutated tumors had PI3KCA(-) CTCs
maximal benefit of buparlisib
no benefit of buparlisib.
41. Jaeger B, PLoS One. 2017 Jun 6;12(6)
The HER2 phenotype of circulating tumor cells in HER2-positive
early breast cancer: A translational research project of a
prospective randomized phase III trial
HER2 status of CTCs in 258 patients with HER2-positive primary breast cancer at the time of diagnosis
Aim: reveal discordance rate of HER2 status between primary tumor and CTCs
32% of the CTC-positive
patients exclusively had CTCs
with strong HER2 staining
12% had only CTCs with
negative HER2 staining.
42. Kallergi G, Breast Cancer Research (2015) 17:113
Expression of truncated HER2 on circulating tumor cells
of breast cancer patients
The truncated form of human epidermal growth factor receptor 2 (p95HER2) lacks the HER2 extracellular
domain and has been associated with poor prognosis and resistance to trastuzumab
p95HER2 receptor was identified in 40%
of patients with metastatic disease
Treatment with Trastuzumab increased the percentage of
patients with p95HER2-positive CTCs from 40 % to 63 %.
Overall survival of patients with p95HER2-positive
CTCs was significantly decreased (p=0.03).
43. Kallergi G, Intern. Conference on Antimicrobial Agents and Chemo. 2015
Isolation and characterization of circulating tumor cells
(CTCs) in triple negative breast cancer patients in
response to chemotherapy
55 early Triple negative breast cancer patients
before and after adjuvant chemotherapy
CTCs were detected in 60% after the completion
of adjuvant chemotherapy
But, the goal is not only to exclude useless therapies
More important: detection of new targets in a certain patient,
targets that didn’t exist in primary tumor and have been raised during metastasis formation.
These targets can be omitted by a spot biopsy of a metastatic lesion
Agelaki S, Oncotarget, 2017, Vol. 8, (No. 3)
Phenotypic characterization of circulating tumor cells in
triple negative breast cancer patients
26%, 34% and 51% of CTCs from patients with triple
negative MBC express ER, PR and HER2 respectively.
The percentage of ER-, PR-, HER2-expressing
CTCs was 26%, 34% and 57% respectively
44. Fehm T, Breast Cancer Res Treat. 2010 Nov;124(2):403-12
HER2 status of circulating tumor cells in patients with
metastatic breast cancer: a prospective, multicenter trial
245 patients with metastatic breast cancer
HER2(+) CTCs in HER2(-) primary tumors:
32% CellSearch assay
49% AdnaTest BreastCancer
Addition anti-HER2 therapy in patients with HER2(-) tumors and HER2 (+) CTCs ?
Apostolaki S, Breast Cancer Res Treat. 2008 Nov
Detection of occult HER2 mRNA-positive tumor cells
in the peripheral blood of patients with operable breast
cancer: evaluation of their prognostic relevance
216 women with early breast cancer
HER2mRNA(+) CTCs were detected in 25% of patients
with HER2(-) primary tumors
Why not ?
Why administrate hormonal therapy in metastatic patients with 1% ER(+) tumors.
45. Phase II Studies with Single Agent Lapatinib
PR: 1.4%, Clinical Benefit: 5.7% PR: 5.1%, Clinical Benefit: 9.0%
Burstein HJ, Ann Oncol. 2008 Blackwell KL, Ann Oncol. 2009.
Disappointing results ?
Agelaki S, PLoS One. 2015 Jun 17;10(6)
Efficacy of Lapatinib in Therapy-Resistant HER2-Positive Circulating Tumor
Cells in Metastatic Breast Cancer
22 patients with HER2(-) tumors and HER2(+) CTCs
In 5 (23.8%) patients, HER2(+) CTC counts increased
in 14 (66.6%) patients HER2(+) CTC counts decreased
the decrease was significant only among patients presenting
disease stabilization (p = 0.018) but not among those with
disease progression during lapatinib treatment
no objective responses, stable disease 11 (52.4%) patients
median PFS 4.0 months, 1-year PFS rate 14.3%
46. Anti-HER2 treatment in advanced metastatic HER2-negative breast cancer patients with elevated serum
levels of the HER2 extracellular domain and/or HER2 overexpressing circulating tumor cells
Kurbacher C, ASCO 2017 abstr 597
31 pts with HER2(-) MBC exhibiting sHER2 values > 15 ng/mL (n = 8), HER2+ CTCs (n = 7), or both (n = 16)
Pts received Anti-HER2 (H, L or P) treatment alone or in combination with another treatment
Anti-HER2 Tx is effective in pts with pretreated
occult HER2(+) MBC and HER2(-) primary
tumor.
Median number of prior treatments: 7
49. Adapted from: T. N. Schumacher and R. D. Schreiber (2015) Science 348, 69
and L. B. Alexandrov et al. (2013) Nature 500, 415
Immunotherapy
It is known that mutational load of primary breast cancer
is moderate, thus is not a suitable tumor for immunotherapy.
50. Luen SJ, Lancet Oncol. 2017 Jan;18(1):52-62
Tumour-infiltrating lymphocytes in advanced HER2-positive breast cancer treated with pertuzumab or
placebo in addition to trastuzumab and docetaxel: a retrospective analysis of the CLEOPATRA study
pre-existing T-cells
vary by site of metastasis.
But, the cancer immune microenvironment is not static.
It evolves and differentiate during metastasiogenesis…
51. …and changes with therapeutic intervention
Accumulation of CD11c+ dendritic cells and enhanced
CD8+ activation in breast tumors were demonstrated in
mice treated with cisplatin
Elevation of TIL percentage
has been demonstrated after taxane neoadjuvant therapy,
and this reaction correlated with clinical response
Anthracyclines can stimulate CD8+ lymphocyte
proliferation in tumors
trastuzumab could modulate immune
activity by reducing the level of circulating Tregs
Kang TH, Cancer Res. 2013;73(8):2493-2504.
Demaria S, Clin Cancer Res. 2001;7(10):3025-3030.
Mattarollo SR, Cancer Res. 2011;71(14):4809-4820.
Horlock C, Br J Cancer. 2009;100(7):1061-1067.
52. Ali HR, Annals of Oncology 26: 1488–1493, 2015
PD-L1 protein expression in breast cancer is rare, enriched
in basal-like tumours and associated with infiltrating lymphocytes
3916 primary tumour samples from 3 clinical studies
(SEARCH, NEAT and METABRIC)
(Basal-like)
PD-L1 expression by immune cells was observed in
6% of tumours and expression by tumour cells was
observed in just 1.7%.
PD-L1 was most frequently expressed in basal-like
tumours (39% of IntClust 10 in METABRIC study
and 19% of basal-like in SEARCH and NEAT studies).
PD-L1 has been used in many studies
as a bio-marker and in many tumors
correlates with immunotherapy effectiveness
53. Zhang M, Oncotarget, 2017, Vol. 8, (No. 19)
Expression of PD-L1 and prognosis in breast cancer:
a meta-analysis
5 studies containing 2,546 cases
PDL1 expression was increased in patients with
- positive lymph node metastasis (P=0.02)
- higher histological grade (P < 0.001)
- estrogen receptor (ER)-negativity (P=0.008)
- triple negative breast cancer (TNBC) (P < 0.001)
54. But, PD-L1 expression is a dynamic process which regulated
by various cytokines during the course of disease
Upregulation Downregulation
primary breast tumor
PD-L1(-)
lung metastasis
PD-L1(+)
Ashley Cimino-Mathews , Hum Pathol. 2016 January ; 47(1): 52–63.
As result, metastatic lesions obtain a different profile of immune reactivity than primary tumors.
55. Additionally, PD-L1 expression can changes after therapeutic
interventions…
Mengqi Y, Molecular Oncology11(2017) 358–372
Chemotherapy induces tumor immune evasion by upregulation of
programmed cell death ligand 1expression in bone marrow stromal cells
Sun W et al., abstract JCSE 01.16
Altered Expression of Programmed Death-1 Receptor (PD-1) and its
Ligand PD-L1, PD-L2 after Neo-Adjuvant Chemotherapy in Lung Cancer
McDaniel A, European Urology Focus 2016, 265-268
Expression of PDL1 (B7-H1) Before and After
Neoadjuvant Chemotherapy in Urothelial Carcinoma
Song Z et al., Lung Cancer 2016, V99 166-171
Altered expression of programmed death-ligand 1 after neo-adjuvant
chemotherapy in patients with lung squamous cell carcinoma
Sharabi AB et al., Lancet Oncology 2015, Volume 16, No. 13, e498–e509
Radiation and checkpoint blockade immunotherapy: radiosensitisation
and potential mechanisms of synergy
56. Mazel M, Mol Oncol. 2015 Nov;9(9)
Frequent expression of PD-L1 on circulating
breast cancer cells
Peripheral blood samples from 16
HR(+), HER2(-) metastatic breast cancer patients
with a CTC count >1 using the CellSearch system
Eleven patients out of 16 showed a
subpopulation of CTCs expressing PD-L1 (68.8%)
The fraction of PD-L1(+) CTCs varied from 0.2 - 100%.
57. Pizon M, ASCO 2016 abstr 3071
Frequency of PDL-1 expressed on circulating epithelial tumor cells (CETCs)
compared to PDL-2 and role in immune evasion in cancer progression
CETCs were determined from blood of 66 patients
(16 MBC, 50 early BC)
PDL-1 expressing CETCs were detected in 95 %
PD-L2 in 75%
in all stages…
more frequent after RT
Metastatic tumors that harbor PD-L1(+) CTCs might benefit from check-point inhibitors,
irrespectively of PD-L1 expression of (long ago) excised primary tumor.
58. Pizon M, Breast Cancer Symposium, 2014
In vitro chemosensitivity testing of mammospheres cultured from circulating epithelial tumor
cells (CETCs) of breast cancer patients: Comparision to chemosensitivity of total CETCs
A subpopulation of CTCs with proliferation activity has the ability to form floating spheres in suspension culture
- CTCs isolation (Maintrac)
- Culture in conditions favoring growth of epithelial cells
- Determination of sphere formation
- Addition of anticancer drugs
- Image analysis of CTCs and spheroids
using the Scan^R Fluorescence microscopy
59. Min Yu, Science. 2014 July 11; 345(6193): 216–220
Ex vivo culture of circulating breast tumor cells
for individualized testing of drug susceptibility Long-term oligoclonal CTC cultures from six patients
with metastatic luminal subtype breast cancers
Cell viability after
treatment of CTC
lines with selected
anticancer drugs,
according to detected
mutations that have
been previously
recognized by NGS
60. In Summary…
Detection, enumeration and characterization of circulating tumor cells in metastatic breast cancer
could be useful for
- estimate risk of progression and death from disease
- real time monitoring therapeutic response
- guidance of therapeutic strategy
- recognition of heterogeneous resistance mechanism
- identification of new therapeutic targets
- understanding the biology of metastatic development.