personalized radiotherapy of breast cancer

1. Personalizovana radioterapija
karcinoma dojke
Sandra Radenkovic

2. Personalizovana medicina
Mogućnosti primene
 Pravi lek
 Odgovarajućem pacijentu
 Za pravi tumor
 U pravo vreme
 Sa adekvatnom dozom
Genetski i metabolički podaci
omogućuju da prava terapija
primenjuje odgovarajućoj
podgrupi pacijenata

3. "Here's my
sequence...”

4. Personalizovana medicina ili
prediktivna medicina
Pacijentkinje sa istom dijagnozom
Odgovor na terapiju
Bez odgovora na terapiju
Neželjeni efekti terapije

5. Ciljevi radioterapije
 Maksimalna doza na
tumorski volumen
 Uniformna doza na
tumorski volumen
 Najmanja doza na
zdrave organe

6. Glavni ograničenja u
konvencionalnom RT planiranju i
isporici
 Nesigurnost u prostornoj proširenosti bolesti
 Inadequate knowledge of the exact shapes and
locations of normal structures
 Lack of tools for efficient planning and delivery
 Hence……….
large safety margins to adequately cover the
target volume

7. Novo lice radioterapije
 Since early 1990s, radiotherapy has become
increasingly technology oriented
 This has resulted in improving the local control
rates and minimizing morbidity

8. Personalizovana RT
Individualizacija
tehnika zračenja i
polja
Selekcija pacijenata i
procena odgovora
Bolji
imidzing
Genomiks
Nove lekovi-
RT
interakcije
Biomarkeri

9. Newer treatment techniques
 Teletherapy
 3D Conformal Radiotherapy
 Intensity Modulated Radiotherapy (IMRT)
 Stereotactic irradiation
 Image Guided Radiotherapy (IGRT)
 Brachytherapy
 Advanced High Dose Rate systems
 Sites previously considered not-possible are easily now

10. Neinvazivni karcinom dojke
Duktalni karcinom in situ (DCIS)
 Postoperativna RT preostalog tkiva dojke nakon
učinjene poštedne operacije (TD 50Gy / 25 frakcija)
 U slučaju mastektomije nema potrebe za
sprovođenjem RT
 Mogućnost izostavljanja postoperativnog RT u
slučajevima sa vrlo niskim rizikom za relaps bolesti
(mali tumori, nizak gradus, stariji pacijenti, margine
>10mm)

11.  Postoperativna RT
 Poštedna operacija
 Mastektomija
 Ciljni volumeni
 Preostalo tkivo dojke
 Zid grudnog koša
 Regionalni limfni čvorovi
Invazivni karcinom dojke

12. Postoperativna RT preostalog tkiva dojke u svim
slučajevima (TD 50Gy / 25 frakcija)
Dodavanje Boost-a na predeo ležišta tumora (TD 10-
16Gy)
Svi pacijenti mlađi od 50 godina
Gradus III tumora
Pacijenti stariji od 50 godina koji imaju povećani rizik za relaps
bolesti
Mogućnost izostavljanja postoperativne RT kod pacijenata
starijih od 70 godina koji imaju dobre prognostičke
parametre (mali tumor, N0, pozitivne steroidne receptore)
Postoperativna RT nakon
poštedne operacije

13. Zid grudnog koša – po pravilu se ne zrači
RT se sprovodi u sledećim slučajevima:
Invazija hirurških margina
Invazija pektoralnog mišića
Pozitivno >4 limfna čvora u aksili
Razmotriti RT u slučaju tumora <5cm kada je
gradusa III, multicentrični Tu, mlađe pacijentkinje
TD 50Gy / 25 frakcija
Postoperativna RT nakon
radikalne mastektomije

14. Akslarna regija
Po pravilu se ne zrači ako je učinjena adekvatna radikalna
disekcija
RT se sprovodi u slučajevima:
Neadekvatna disekcija aksile
Rest u aksili nakon disekcije
Nije rađena disekcija aksile
Pozitivna SLNB bez dalje disekcije aksile
Supraklavikularna regija
Pozitivno >4 limfnih čvora u aksili
Pozitivno 1-3 limfna čvora sa drugim nepovoljnim parametrima
Neadekvatna disekcija aksile
Lgl uz A.mamariju internu
Ne preporučuje se RT
TD 46-50Gy / 23-25 frakcija
Postoperativna RT regionalnih limfatika nakon
radikalne mastektomije ili poštedne operacije
ranog karcinoma dojke

15. Subkutana mastektomija sa
primarnom rekonstrukcijom
 Indikacije za postoperativnu RT zida grudnog
koša sa endoprotezom i regionalnih limfatika su
iste kao i nakon radikalne mastektomije

16. Redosled postoperativne RT i
adjuvantne HT
 Početak postoperativne RT unutar 8 nedelja od
učinjene operacije
 Ukoliko se RT kombinuje sa adj.HT (antraciklini i
taksani) prvo se sprovodi HT a potom RT

17. Radioterapija lokalno
odmaklog karcinoma dojke
Postoperativna RT
 U slučaju odgovora na neoadj.HT i učinjenu
operaciju (mastektomija ili poštedna
operacija)
Preoperativna i radikalna RT
 U slučaju izostanka odgovora na HT i
inoperabilnostiTu

18. Neoadj.HT + mastektomija
 Odluka o postoperativnoj RT na osnovu karakteristikaTu pre
primenjene HT bez obzira na odgovor na HT
 Zid grudnog koša
 InicijalnoT3 iliT4
 Pozitivno >4 lgl u aksili
 Regionalni limfni čvorovi
 Iste indikacije kao i nakon operacije ranog Ca dojke
Aksilarna regija
 Pozitivno >50% pregledanih lgl
 Pozitivno >10 lgl bez obzira na broj pregledanih lgl
Lgl uz a. mamariu internu
 Klinički ili patohistološki dokazana zahvaćenost ovih lgl

19. Neoadj.HT + poštedna operacija
 Postoperativna RT ostatka dojke
 Obavezna
 Regionalne lgl
 Iste indikacije kao i nakon operacije ranog CA dojke

20. Inoperabilni tumor posle
neoadj.HT
 Zračni volumeni
 Dojka
 Svi regionalni limfni čvorovi
 TD 50-70Gy

21. ODREĐIVANJE KONTURA
Definisanje ciljnih volumena i OR
Contouring at:
- Focal
- FocalSim
- XiO

22. Definisanje
parametara zračenja:
• postavljanje izocentra
• aranžman polja
• veličina
• uglovi gentrija
• kolimatora

23. Standardna tangencijalna polja VS 3D/IMRT
• Nema statisticke značajnosti u 5-godisnjem
preživljavanju
• Lokoregionalna kontrola 2.56% VS 1.35 %
OS 92.5 % VS 91.7 %
JCO 2013 ;31 : 4488-4495
IJROBP 2008 ;72 :1031-1040

24. Parcijalno ozračivanje dojke
Implantacija
Mammosite
(3D-CRT / IMRT)
Intrabeam

25. Zračenje dojke u pronaciji
Pozicioniranje pacijenata

26. Delivery of IMRT fields :
Dynamic MLC
Leaf A Leaf B
Position
Intensity
Continuous modulation

27. IGRT: to overcome
organ motion and
setup errors

28. Tumor
Cross-sectional View
of Patient’s Chest
Tumor
Some motion is mostly
Anterior / Posterior
Some motion is mostly
Superior / Inferior
All tumor motion is
Complex
Tumor Motion During
Respiration
 All tumor motion is
complex

29. Image Acquisition with breathing phase

30. Cone Beam CT Mode – Axial
(z) Geometry
z
Transaxial ~ Transaxial
For single- and multi-slice CT scanners
the slices are approximately parallel.
This does not apply to Cone Beam CT.

31. Cone Beam CT Mode – Axial
(z) Geometry
z
Transaxial ~ Transaxial Cone Beam
Volumetric
Image
17 cm

33. CT Scan SPECT IMRT
Treatment
Functional Imaging - Nuclear
Medicine

34. PTV
PTV
GTV
Hypoxia
• PET (F-
miso)
Tumor Growth
• PET (IUDR)
Tumor Burden
• MRI
• MRS (choline/citrate)
Functional Target Volume?
Biological Target Volume?
GTV
What is the Target?-
Functional Target Volumes

36. Personalized medicine today yesterday
 Cytochrome P450 genotyping test
 Enzyme group ‘cytochrome P450’ (CYP450
 Many types of medications(including antidepressents,
anticoagulants, proton pump inhibitors, etc)
 Determine dosing and effects of these drugs.
 Dihydropyrimidine dehydrogenase test
 5-flourouracil (5-FU)
 Dihydropyrimidine dehydrogenase enzyme
 Responsible for breaking down 5-FU

37. Gen Lek Razlog testiranja Genska izmena Metod
UGT1A1 Irinotecan Toksičnost, neutorp/diareja UGT1A1*28 1.Invader esej
2. Sekvenciranje
CYP 2D6 Tamoxifen Izbor pac za inhib aromataze ili
povećanje doze tamoksifena
Polimorfizmi 1. Mikroarej-AmpliChip,
2. Alel-specifini real-time PCR
DPD 5-FU, Xeloda Toksičnost DPYD-ceo gen PCR-RFLP
TS 5-FU Predikcija rezistencije TS – TSER*2 vs. TSER*3 PCR-RFLP
MTHFR Methotrexat Toksičnost C677T (i A1298C) PCR-RFLP
EGFR Cetuximab,
Panitumumab
Aktivnost EGFR gene copy number-
amplifikacija
FISH
EGFR TK inhib. Lekovi izbora ako je mutiran EGFR mutacija Real-time PCR
K-Ras Cetuximab Wild-type odgovara na cetuksimab Mutacija Real-time PCR
B-Raf Cetuximab Ne odgovara na cetuximab i ako je K-
Ras wt (oko 15%)
Mutacija Real-time PCR
ERCC1, XPD CDDP, Oksaliplatin Rezistencija Ekspresija proteina WesternBlot, ICH
Glutation S-
transferaza
Oksaliplatin Neurotoksičnost GSTP1-105G alel
polimorfizam
Sekvenciranje
Mikrosatelitna
nestabilnost
Kolorektum,
ovarijum
Predikcija aktivnosti MSI Sekvenciranje
BcrAbl Imatinib CML praćenje terapije Translokacija Real-time PCR
C-kit Imatinib GIST rezistencija Mutacija Sekvenciranje
HER-2 Trastuzumab Aktivnost Prekomerna ekspresija ICH, FISH
Tiopurin
metiltransveraza
Azatioprin,
tiogvanin,
merkaptopurin
Toksicnost Mutacija Sekvenciranje, Real-Time PCR

38. Primeri!
Biomarker Primena
Her-2/neu receptor Selektovanje pacijentkinja za
Herceptin (trastuzumab) za
pacijentkinje sa karcinomaom dojke
BRCA1/2 Breast cancer inherited risk,
prophylactic tamoxifen and surgery
Transcriptional profile – 21 genes Avoid use of chemotherapy in breast
CA patients with low risk of
recurrence
CYP2D6/CYP2D19 Guide prescribing/ adjust dose of
~25% of commonly used drugs

39. From Bench to Bedside:
Complexity of the Human
Being
Biomarkers related to the host
Clinical Outcomes
-Hard outcomes (OS/DFS)
-Soft outcomes (toxicity/QOL)
Biomarkers of tumor
Environmental Modifying Factors
Treatment Factors
Psychosocial
Cultural, Economic
Non-causal
Prognostic Factors
Causal Prognostic Factors
Adapted from Liu et al, 2006
Radio-genomics

40. Pathways and Mechanisms of Tissue
response to Irradiation

41. Radiogenomics & Personalised
RT
 60% cancer patients require radiotherapy
 The 3 main predictors of response to RT are:
 Intrinsic radiosensitivity
 Tpot (tumor proliferative potential)
 Tumor oxygenation
 These can be studied in vitro by:
 Assessing SF2 (surviving fraction at 2 Gy exposure)
 Clonogenic survival assays
 DeterminingTpot
 Measuring tissue oxygenation using electrodes

42. Measuring SF2 by clonogenic
survival assays
 Has been the gold standard
 Some data exists to show relation between SF2 and inherent
radio sensitivity of tumor tissue
 However its clinical application has not been widespread
because of the difficulties of in vivo testing as well as because
of further interactions with environmental factors and
signalling / transduction pathways.

43. Clinical
response and
oxygenation
 Well recognised clinical
theory since action of
irradiation depends on
generation of free radicals.
 Eppendorf probe most
successful one used.
 Extensive studies on
hypoxia in cervical cancer
causing poor response.
 This method limited by
accessibility of tumor (in
head and neck / cervix
cancers).
 Hypoxia inducible protein-
alpha now being studied;
considered better
biomarker.

44. Biologija hipoksije tumora
Hipoksični
Region
Krvni sud
O2 /
Koncentracija
leka
Genska/proteinska
regulacija
Povećanje glikolize
Ubrzana angiogeneza
Povećanje genomske nestabilnosti
Selekcija of rezistentnih ćelija
na apoptozu
Rezistencija na hemoradioterapiju

45. From Meijer et al Clin Cancer Res, 18: 5585-5594, 2012
HIF-1 (Hypoxia-inducible factor-1) enables
tumour cells to survive hypoxia

46. Role ofTpot
 Basically study of
potential doubling time
of tumour
 Large studies by EORTC
shown little or no
correlation with survival.
 Is a weak predictor of
outcome
Correlation of DNA End-Binding
Complexes With Cellular Radiosensitivity
 DNA damage activates many signal
transduction cascades like ataxia
telangiectasia mutant (ATM) and DNA-
dependent protein kinase pathways
(DNA-PK)
 assay to analyze DNA end-binding
complexes: identified rapidly migrating
ATM-containing band (B and A), the
density correlated with radiosensitivity.

47. Predicting radio-sensitivity
from genetics
It is estimated that nearly 80% of inter-individual variation in normal tissue
response to radiation might be due to genetic factors (Turesson et al. 1996).
Radiation therapy also has a relatively narrow therapeutic index (Turesson
1990; Bentzen et al. 2008).
Therefore, understanding the biology might help us to maximize radiation
efficacy in the tumor, while minimizing side effects in normal tissues.
Several radio-genetic studies have shown that genetic polymorphisms in
genes within known radiation response pathways are significantly
associated with radiosensitivity.
These include endogenous oxidative stress defense, inflammatory
response, cytokine activity related to fibrosis, DNA damage signaling, cell
cycle control, and DNA repair

48. Predicting radio-sensitivity
from genetics
 Apoptosis has been associated
with the ATM-p53-Bax-
Cytochrome c-Caspases pathway
 Mitotic catastrophe involves the
p53-Caspases-Cytochrome-C
cascade
 For necrosis, TNF (alpha) -PARP-
JNK-Caspases pathway is involved
 MYC-INK4A-ARF-p53-p21
pathway has been implicated in
senescence.
 In autophagy, the PI3K-Akt-mTOR
cascade is important

49.  genome-wide association study (GWAS) to identify biomarkers to predict
radiation response using 277 ethnically defined human lymphoblastoid
cell lines (LCLs).
 Basal gene expression levels and 1.3 million genome-wide single
nucleotide polymorphism (SNP) markers were assayed for all 277 human
LCLs.
 Functional validation of candidate genes, selected from an integrated
analysis that used SNP, expression, and AUC data, performed with
multiple cancer cell lines using specific siRNA knockdown, followed by
MTS and colony-forming assays.

50.  A total of 270 expression probe sets were associated with radiation AUC
with P < 10–3. The integrated analysis identified 50 SNPs in 14 of the 27 loci
that were associated with both AUC and the expression of 39 genes, which
were also associated with radiationAUC (P < 10–3).
Expression of five
genes:
C13orf34, MAD2L1,
PLK4, TPD52,
DEPDC1B, involved in
radiation-induced
response.

51. Predicting radio-sensitivity
from genetics
 A study from Singapore proposed a Radio-sensitivity Index based on
identification of genes as a biomarkers.
 In sites such as breast, colon, melanoma, non-small cell lung,
ovarian, renal and prostate cancer.
 A ten gene network thought to play a central role in determining
radio-phenotype.
 Cellular radio-sensitivity as a linear function of gene expression for
the ten genes was quantified by cell survival.
 Is currently undergoing further clinical validation under US FDA for
clinical use. This RSI can predict therapeutic benefit independent of
the disease site.
Torres Roca JF, Eschrich S, Zhao H et al. Prediction of radiation sensitivity using a gene
expression classifier. Cancer Res.65(16),7169–7176 (2005).

56. Predikcija radiotolerancije i
neželjenih efekata RT pomoću
genetike
 ATM gene  generalizovana radiosenzitivnost i toksičnosst
pacijentkinja sa karcinomom prostate;
 XRCC gene  Kasna fibroza kod pacijentkinja sa karcinomom dojke
nakon zračne terapije i postiradijacioni dermatitis
 TGFbeta citokin inhibira proteolitičku aktivnost esencijalnu za
ćelijski metabolizam.
Smatra se da je radiosenzitivnost nasledna
poligenska karakteristika zavisna od interacije
mnogih gena uključenih u više ćelijskih procesa

57. Bioscience November 2015
Comet assays of circulating lymphocytes also give
valuable information on radiation induced tissue
damage patterns

59. Cancer Pharmacogenetics
Cancer Pharmacogenomics
Biomarkers Predictive for
Drug Outcomes
Biomarkers Predictive for
Treatment Outcomes
+
Personalisation of radiotherapy
delivery
GERMLINE
SOMATIC or TUMOUR
PROTEINS, IMAGING
RADIATION THERAPY

60. Cancer
Patients
Germline
/ Somatic
Genotype
Prediction of
Drug Efficacy
Incorrect
Genotype
Assignment
• Improved
Outcomes
• Enhanced
Response
• Minimize
Toxicity
Harms of
Subsequent
Management
Options
Treatment
Decisions
Clinical Validity Clinical Utility
Overarching Question
Prediction of
Metabolism
Prediction of
Adverse Drug
Reactions
Analytic Framework + Key Questions for Evaluating
Genomic Tests in a Specific Clinical Scenario

61. Cancer
Patients
Germline
/ Somatic
Genotype
Prediction of
Drug Efficacy
Incorrect
Genotype
Assignment
• Improved
Outcomes
• Enhanced
Response
• Minimize
Toxicity
Harms of
Subsequent
Management
Options
Treatment
Decisions
Clinical Validity Clinical Utility
Overarching Question
Prediction of
Metabolism
Prediction of
Adverse Drug
Reactions
Analytic Framework + Key Questions for Evaluating
Genomic Tests in a Specific Clinical Scenario

62. THANK YOU