università degli studi di palermo centro interdipartimentale di ricerca in oncologia clinica (dir.:...

Università degli Studi di PalermoCentro Interdipartimentale di Ricerca in

Oncologia Clinica(Dir.: Prof. N. Gebbia)

Antonio Russo

Roma 5-6 ottobre 2007, Mediterranean School of Oncology

“Hereditary Breast and Ovarian cancer

BREAST AND OVARIAN CANCERBREAST AND OVARIAN CANCER

Sporadic

Hereditary

90%

10%

Sporadic

FamilialHereditary

75-80%

5-10%

15-20%

Breast Cancer Ovarian Cancer

Hereditary Breast Cancer

(HBC)

Hereditary Breast and Ovarian Cancer

(HBOC)

Hereditary Ovarian

Cancer (HOC)

Hereditary Non Poliposis Colorectal Carcinoma

(HNPCC)

Others (Li Fraumeni S., Cowden S., Peutz Jeghers S.,Gorlin S.

Ataxia Telangiatxia S.)

10-15%10-15%

10-15%10-15%

HEREDITARY BREAST AND/OR OVARIAN CANCER SYNDROME

20-30%20-30% <1%<1%

60-75%60-75%

Sporadic Familial

Hereditary

75-80%

5-10%

15-20%

CAUSES OF HEREDITARY SUSCEPTIBILITY TO BC

BRCA1

60%

20-40%

BRCA2

TP53

10-30%

ATM

UNKNOWN PREDISPOSING GENES

PTEN

OTHER KNOWN GENES(e.g. CHK2) 7%

BRCA1

60%

20-40%

BRCA2

TP53

10-30%

ATM

UNKNOWN PREDISPOSING GENES

PTEN

OTHER KNOWN GENES(e.g. CHK2) 7%

CAUSES OF HEREDITARY SUSCEPTIBILITY TO OC

BRCA1

BRCA2

Other genesMMR (MSH1,

MLH2)2%

8-10%

20%70%

Sporadic90%

Hereditary

10%

BRCA1-ASSOCIATED CANCERS: LIFETIME RISK

Possible increased risk of other cancers (prostate, colon)

Male Breast cancer: <1%

Ovarian cancer: 15-45%

Breast cancer: 50-85%

Second primary breast cancer: 40-60%

BRCA1-LINKED HEREDITARY BREAST AND OVARIAN CANCER (HBOC)

BC36

BC45

OC59

Non carrier

Affected with BC

Affected with OC

Affected with other cancer

BC42

BRCA1-LINKED HEREDITARY OVARIAN CANCER (HOC)

OC50

OC59

Non carrier

Affected with BC

Affected with OC

Affected with other cancer

OC42

OC40

BRCA2-ASSOCIATED CANCERS: LIFETIME RISK

Male Breast cancer: 5-10%

Ovarian cancer: 10-20%

Breast cancer: 50-85%

Increased risk of prostate, laryngeal and pancreatic cancers

BC52

BRCA2-LINKED HEREDITARY BREAST CANCER (HBC)

Non carrier

Affected by BC

Affected by OC

Affected by other cancer

BC61

Prostatic cancer

BC59

BC52

GENETIC FEATURES GENETIC FEATURES

OF BRCA GENESOF BRCA GENES

BRCA1 GENE

Tumor supressor gene on chromosome 17 (17q21)

24 exons: 22 encoding

5529 nucleotides

Autosomal dominant transmission

1 1863aa

FUNCTIONAL DOMAINS AND INTERACTING PROTEINS

BRCA1 PROTEIN STRUCTURE

BARD1

BRCA2 GENE

Tumor supressor gene on chromosome 13 (13q12)

27 exons: 24 encoding

10534 nucleotides

Autosomal dominant transmission

BRCA2 PROTEIN STRUCTURE

3418 aa

INTERACTING PROTEIN AND FUNCTIONAL DOMAIN

1

BRCA GENES FUNCTIONSBRCA GENES FUNCTIONS

Narod et al., Nature Reviews Cancer, 2004

PATHWAYS BRCA-MEDIATED

the manteinance of genomic stability

cell cycle checkpoints

remodeling of chromatin

DNA damage response

estrogen responsivness

is a coactivator of p53 responsive genes

BRCA genes involved in:

BRCA1 AND BRCA2 MUTATIONSBRCA1 AND BRCA2 MUTATIONS

BRCA1 BRCA1 ((~ 600 different pathogenic mutations reported)

BRCA2 BRCA2 ((~ 300 different pathogenic mutations reported)

Database BIC (Breast Cancer Information Core), 2006

BRCA MUTATIONS

• Not hot spot mutations

• Prevalence of specific mutation in particular geographic areas and ethnic groups (founder effect)

• New germinal mutations

POPULATION BRCA1 BRCA2

Ashkenazi Jews 185delAG and 5832insC

Icelander 6174delT and 995delG

Norwegian1675delA, 816delGT,

3347delAG and 1135insA

Finn IVS11+3A>G 9345 +1G>A, C7708T and T8555G

French 3600del11 5579insA

Italian

Calabria 5083del19

Sardinia 8765delAG

Sicily 4843delC

BRCA1/2 FOUNDER MUTATIONS IN EUROPEAN POPULATIONS

4843delC NOVEL MUTATION COULD BE SICILIAN FOUNDER MUATION

The homogeneity of the ethnic group of the two families unrelated and the SNPs analysis of probands led us to perform a study of the allelotype of the various members of families to determinate common allele and whether 4843delC might be due to a Sicilian founder effect.

55

36 33 28 24 34 31 28

40 Br 39

65 Ov 65

57 Br 44

FAM64 FAM92

50 41

42 Ov 40

55 Br 53 Br 52

48 Ov 42

44

41 Hep 40

42 Lung 39

70 Leu 68

21 20 23 21

Symbol definitions

Unaffected

Carrier

Deceased

Affected

Deceased affected

Male Female

4843delC (ter1600)

Russo A., Calò V., 2007

HAPLOTYPE ANALYSIS OF BRCA1 GENE IN THE FAMILIES

Twelve members of two families were enrolled for the study.

Non-carriers of the mutation and none of the 50 healthy Sicilian controls had the 4-2-8-2-3 haplotype associated with the 4843delC mutation.

Allelotype analysis highlighted the presence of a ancester common allele in the affected individuals and healthy carriers, therefore suggesting the presence of a founder effect. Russo A., Calò V., 2007

Are of higher histological grade (70% are G3)

Show increased alterations in tumor suppressor gene : TP53 (55-

90%)

Are frequently triple negative phenotype (ER, PgR e c-erb2 negative,

> 80 %)

Show an increased proliferative capacity (higher S-phase fraction)

Are often DNA-aneuploid tumors

BRCA1-RELATED BREAST CANCER

Are of higher histological grade (G3)

High stage

Are frequently serous epithelial carcinomas

Longer survival

Better response to chemotherapy (platinum)

BRCA1-RELATED OVARIAN CANCER

CLINICAL APPLICATIONSCLINICAL APPLICATIONS

Multiple cases of early onset breast cancer

Ovarian cancer (with family history of breast or ovarian cancer)

Multiple cases with family history of ovarian cancer

Breast and ovarian cancer in the same woman

Bilateral breast cancer

Male breast cancer

FEATURES THAT INDICATE INCREASED LIKELIHOOD OF HAVING BRCA MUTATIONS

≤ 50 years (%) > 50 years (%)

BC OC BC OC

BRCA1BRCA1BCLC*

NYBCSG**

5 –50 23 50 – 85 63

3-39 16-40 58-81 28-56

BRCA2BRCA2BCLC*

NYBCSG**

5 – 45 ns 45 – 85 ns

17 - 34 O-1 48 - 85 27

* Breast Cancer Linkeage Consortium, supported by the European Commission (2002)

** New York Breast Cancer Study Group (2003)

BC AND OC LIFETIME RISK ESTIMATED IN BRCA1 AND BRCA2 CARRIERS

CANCER GENETIC COUNSELLINGCANCER GENETIC COUNSELLING

At risk individualAt risk individual Healthy with positive familial anamnesisAffected

Verify of criteria fulfillmentOncology UnitOncology Unit

IC Clinical Data Collection + Pedigree Construction + Risk Estimation

Genetic-oncologic Genetic-oncologic counsellingcounselling

Palma et al., Critical Reviews in Oncology/Hematology, 2006

MULTISTEP CANCER GENETIC COUNSELLING MODEL

Personal information

Age

Hormonal factors:

Age at menarche and menopause

Age at first live birth

Number of children

Number of previous breast biopsies (whether positive or negative)

At least one biopsy with atypical hyperplasia

BC/OC

Age of diagnosis

Treatment

Clinical Data CollectionClinical Data Collection

Pedigree that spans at least three generations

Family factors:

Number of first-degree relatives with BC and/or OC or other cancers

Other chronic diseases in the family

Ethnic background

Age of diagnosis

Treatment

Age of death

Pedigree ConstructionPedigree Construction

Ovarian Kdx 43, d.49

Breast KDx 45, d. 59

BenignProstatic

hyperplasia

Stomach K

Bone Kd. 59

Prostate K

Verbally reported pedigree Revised pedigree based

on pathology reports


Verify family history

Breast K, 40

Ovarian K, 44

Breast K, 40

Initial History 1 years later


Family cancer histories are dinamic

MYRIAD MODEL

• Age at BC diagnosis

• Family history information

• Presence of OC in the family

• Ethnicity

BRCAPRO

• Age at breast cancer diagnosis• 1st- and 2st- degree family history

• Presence of male and female BC

• Presence of OC

• Ethnicity

• Size of family

Risk EstimationRisk Estimation

Factors Considered for estimating the likehood of finding a BRCA Mutation

Performed

Genetic Testing Considered

Risk Communication

Not PerformedIC

Blood Sampling

Molecular Genetic UnitMolecular Genetic Unit Genetic testing


At risk individualAt risk individual Healthy with positive familial anamnesis


Affected



MULTISTEP CANCER GENETIC COUNSELLING MODELMULTISTEP CANCER GENETIC COUNSELLING MODEL


METHODS FOR MUTATIONAL SCREENING


Negative ResultPositive Result Not Informative Result

2nd Blood Sampling


Performed


Risk Communication

Not PerformedIC

Blood Sampling



Affected



MULTISTEP CANCER GENETIC COUNSELLING MODELMULTISTEP CANCER GENETIC COUNSELLING MODEL

Genetic testing

Negative Result Emphasize risk of unidentified familial mutation Provide individualized risk-management plan

Not Informative Result(Variants of Uncertain Clinical Significance)

Cancer risk associated with mutation cannot be assessed Possible to test other family members to verify the segregation of mutation Provide individualized risk-management plan Carry on additional investigation (functional and epidemiological studies)

Positive Result

Consider BRCA1/BRCA2 testing for specific mutation to other

family membrers

Positive Result

Negative Result

Not performed

Prevention strategy

Ruotine breast screening as

general population

Prevention strategy

Report Trasmission

Report given to the patient

Negative ResultPositive Result Not Informative Result

2nd Blood Sampling

Performed


Risk Communication

Not PerformedIC

Blood Sampling




Affected



MULTISTEP CANCER GENETIC COUNSELLING MODEL

Prevention Strategies Definition


Oncology UnitOncology Unit

Molecular Genetic UnitMolecular Genetic Unit

Positive BRCA1 or BRCA2 test result

increased surveillance

PREVENTION STRATEGY OPTIONSIN BRCA MUTATION CARRIERS

INCREASED SURVEILLANCE

Recommended for breast cancer detection in women

Monthly self-examination of the breast (18 years)

Clinician breast exam, every 6 months (25 years)

Echography every 6 months and/or mammography and MRI every year:

- < 35 ys (25 years): Echography every 6 mts

- > 35 ys: Echography every 6 mts + MRI and mammography every year

- 5-10 ys prior to the youngest diagnosis of BC in the family

Reduces mortality by approximately

25-30% in women in their 50s

18% in women in their 40s

National Comprehensive Cancer Network – Practice Guidelines in Oncology (2006)


Recommended for breast cancer detection in men

Monthly self-examination of the breast

Annual clinician breast exam

Annual mammography

Adhere to population screening guidelines for prostate cancer


Recommended for ovarian cancer detection

Pelvic examination annually (>18 years)

Transvaginal ultrasound, every 6 months (25-35 years)

Serum Ca 125, 6-12 months (25-35 years)


Not prevent cancer, but it can diagnose cancer at earlier stage

(associated with better survival)



Increased Surveillance

Lifestyle Change


LIFESTYLE CHANGE

Overweight, fat intake, alchool intake, physical activity

Difficult valutation of above-mentioned factors

Long time to really define if the change of lifestyle could cause a

risk’s decrease

Hormone Replacement Therapy (HRT)

Women on prolonged hormone replacement therapy (> 4 years) have

a slightly increased risk of BC

Oral Contraceptives

Continuative use (6 years): 60% reduction in frequency of OC, but

significant correlation with risk of BC (RR = 1.2)




Lifestyle Change

Chemo-prevention

PREVENTION STRATEGY OPTIONS FOR BC IN BRCA MUTATION CARRIERS

TAMOXIFEN

Four randomized trials have evaluated Tamoxifen as chemoprevention

agent in the treatment of high risk pts

Significant reduction of invasive BC incidence in the two major trials

(NSABP-1 and IBIS I)

No significant results in the Royal Marsen Hospital Trial and Italian

Trial

OTHER CHEMOPREVENTION TRIALS

STAR (tamoxifen vs raloxifen)

MAP.3 (anastrazole vs placebo) and ApreS (exemestane vs placebo)

CHEMOPREVENTION

CHEMOPREVENTION SOME CONSIDERATIONS FOR BRCA MUTATION CARRIERS

BCs developed in BRCA1 carriers were mostly ER negative (>80%)

while those developed in BRCA2 carriers were prevalently ER positive

(75-80%)

Thus, BRCA2 mutation carriers may be the subset that benefits the

most from anti-estrogen PMT while chemoprevention by estrogen

blockade, in BRCA1, is yet to be elucidated.

Review literature, 2006

SOME OPEN QUESTIONS:

Durability of the preventive effect

Type of preventive treatment

Which subsets benefit from treatment

Interaction with HRT

Preventive effect in BRCA1/2 carriers

CHEMOPREVENTION TRIALSSOME CONSIDERATIONS



Lifestyle Change

Chemo-prevention

Prophilactic Surgery


Bilateral prophylactic mastectomy (total or skin-sparing)

Should be limited to women at very risk (such as patients with lobular

carcinoma in situ (LCIS) or those who are known carriers of BRCA1/BRCA2

mutations)

Should reduce BC risk by at least 90% Salpigo-oophorectomy upon completion childbearing

Should reduce BC risk by at most 50%

Should reduce OC risk by at least 95%


PROPHYLACTIC SURGERY

Surgical procedures cut down the risk but DON’T SET IT AT ZERO!

Prophylactic mastectomy and oophorectomy are two controversy procedures

Hereditary Breast Cancer

(HBC)

Hereditary Breast and Ovarian Cancer

(HBOC)

Hereditary Ovarian

Cancer (HOC)

Hereditary Non Poliposis Colorectal Carcinoma

(HNPCC)

Others (Li Fraumeni S., Cowden S., Peutz Jeghers S.,Gorlin S.

Ataxia Telangiatxia S.)

10-15%10-15%

10-15%10-15%

HEREDITARY BREAST AND/OR OVARIAN CANCER SYNDROME

20-30%20-30% <1%<1%

60-75%60-75%

HNPCC- Lynch II Syndrome

Early but variable age at CRC diagnosis (~ 45-50 years)

Tumor site in proximal colon

Risk of metachronous CRC is increase (50% after 15 years)

Extracolonic cancers

100

80

60

40

20

0

0 20 40 60 80

Age (years)

Cancer Risks in HNPCC

% with cancer

Colorectal 78%

Endometrial 43%

Stomach 19% Biliary tract 18%

Urinary tract 10%Ovarian 9-12%

Review literatura, 2007

Genetic Features of HNPCC

Autosomal dominant inheritance

Penetrance ~ 80%

Genes belong to DNA mismatch repair (MMR) family

Genetic heterogeneity: MSH2 (Chr.2p), MLH1 (Chr.3p),

PMS1 (Chr.2q), PMS2 (Chr.7p), MSH6 (Chr.2p).

Genetic Features of HNPCC

MMR deficiency qualifies as mutator phenotype.

MMR deficiency in these tumors causes microsatellite instability, which can be viewed as the extreme manifestation of general genomic instability and provides an excellent marker of MMR deficiency.

Modified by Harfe et al., Mutation Research 2000

Contribution of Gene Mutations to HNPCC Families

MSH2 ~ 60%

MLH1~ 30%

MSH6 (rare)

PMS2 (rare) PMS1 (rare)

Patients with HNPCC have 3.5-8 fold increased risk of OC

Patients with mutations in MSH2 appear to have particularly increased risk for OC

Individuals who should consider testing for HNPCC

Bethesda criteria

Two first-degree relatives with colorectal cancer plus a third with early onset colon cancer or endometrial cancer.

Amsterdam criteria

Family history of two or more successive generations with colorectal cancer

One or more relatives diagnosed with colorectal cancer prior to the age of 50

Colon cancer diagnosed in at least three relatives

Increased family incidence of other cancers (such as ovary, uterus, stomach, urinary tract, small bowel and bile duct)

When a family fulfills the Bethesda criteria, which includes the Amsterdam criteria, examination of tumor tissue is indicated.

IHC and MSI (prescreening tests)

and then DNA mutation analysis in blood.

Genetic testing for HNPCC

Surveillance Options for Carriers of HNPCC-Associated Mutations

Malignancy

Colorectal Cancer

Endometrial and Ovarian Cancer

Recommendation

Begin at age 20-25, repeat every 1-2 years

Annually, starting at age 25-35

Intervention

Colonoscopy

Transvaginal ultrasound

Endometrial aspirate

Prophylactic Surgery Options for HNPCC-Associated Mutation Carriers

Options include subtotal colectomy, hysterectomy, and

oophorectomy

Surgery does not eliminate cancer risk

Expert panel made no recommandation for or against

surgery due to unproven efficacy

Conclusions Pratical point

Family history is strongest risk factor for breast and/or ovarian cancer

Pts with a family history of BC and/or OC are classified into 4 main groups: HBOC, HBC, HOC and HNPCC (Lynch syndrome type II)

• HBOC, HBC and HOC are due to mutation in the BRCA1 and BRCA2 genes

• Lynch II is due to mutation in the MMR genes

ConclusionsPratical point

5. Pts at high-risk of BC and/or OC should be referred for genetic counselling and potential genetic testing

6. Pts at high-risk of BC and/or OC may be offered various options for management: intensive cancer surveillance chemoprevention and prophylactic surgery

7. Prophylactic surgery provides the most protection against development of future BC and/or OC, but it does not reduce the risk to zero

• Identification of proteomic and/or genomic patterns that may aid in early BC and/or OC detection in high-risk women

• Clinical trials of chemoprevention

ConclusionsResearch directions

università degli studi di palermo centro interdipartimentale di ricerca in oncologia clinica (dir.:...

Documents

ovarian cancer multiple

family history of breast

delc mutation

sicilian founder effect

sicilian founder muation

delc novel mutation

delc ter1600 russo

families unrelated