rossitza tacheva, md assistant professor of pathology, anatomy and cell biology gynecologic...
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Rossitza Tacheva, MDAssistant Professor of Pathology, Anatomy
and Cell Biology
Gynecologic Cytopathology
OverviewCervical cancer screeningThe conventional Pap test Liquid based PapBethesda System for reporting Pap testExamples of normal and abnormal PapHPV and cervical cancerClinical utilization of HPV testingScreening guidelines in USACervical cancer prevention in the future
Screening Cervical CancerScreening Cervical Cancer
The Pap Test has been the most successful cancer screening program in history
Cervical cancer incidence and mortality have dropped in all populations with organized screening programs
In unscreened populations death from cervical cancer remains high, especially in developing countries
PAP (Papanicolaou) TestPAP (Papanicolaou) TestEarly detection of cervical cancer precursor lesions
(dysplastic changes) is the rationale for the Pap testNatural progress of invasive cervical cancer from pre-
invasive to invasive disease (average time 10 y) Cervical precancerous lesions are associated with
abnormalities in Pap smears that can be detected long before any abnormality is visible on gross inspection
Relatively easy to obtain the material and inexpensiveThe association with molecular test for HPV further
increases the sensitivity in the detection of lesionsSuccessfully treated
Rates Cervical Cancer Rates cervical cancer
Goldie et al Vaccine 2006
Cervical cancer USA 2014Cervical cancer USA 2014
13,000 cases per year4,000 deaths
Cervical Cancer ScreeningCervical Cancer Screening
Over time, cervical cancer screening has evolved from a single glass slide smear to a test involving liquid-based processing and molecular HPV testing
DR. PAPANICOLAOU INTRODUCED THE PAP TEST IN 1941
CONVENTIONAL PAP TEST
Pap TestPap Test
Most Pap tests in the United States are now processed from a liquid-based medium as opposed to having the cells smeared directly onto a glass slide
PAP TEST-liquidbased
THINPREP
PAP TEST-liquid-based
THINPREP
An Important ChangeAn Important Change
Cells are collected
in a vial of Preservcyt® solution
Fully automated
Minimizes blood, mucus, non-diagnostic debris
Dispersion Cellcollection
Cell transfer
The ThinPrep 2000 ProcessorThe ThinPrep 2000 Processor
The ThinPrep ProcessThe ThinPrep Process
CONVENTIONAL PAP SMEAR
THINPREP
Endocervical cells
HPV and Cervical CancerIn the last decade it has become clear that
infection with HIGH RISK HPV is required for the development of high grade precursor lesions and cervical cancer.
Dr. Harald zur Hausen in 2008 won Nobel Prize for demonstrating HPV as the etiological agent of cervical cancer.
Cervical Cancer Screening
Recent emphasis on molecular testing seeks to identify HPV strains considered high risk for carcinogenesis
HPV TypesHPV Types
Low- risk: 6,11,40,42,43,44,53,54,61,72,73,84
High-risk:16,18,31,33,35,39,45,51,52,56,58,59,68,82
Possible high-risk: 26,66,73
High-Risk HPV TypesHigh-Risk HPV TypesHPV 16 is found in half of all women with
cervical cancer; also the most commonly identified type in HGSIL and among women in the general population
The second most common HR virus is HPV 18
16 and 18 account for approximately 70% of cases of cervical intraepithelial neoplasia (CIN) and cervical carcinoma
HR HPV incorporate into the genome of the host cell
Low –Risk HPVLow –Risk HPV
HPV 6,11 are the most common typesAssociated with genital warts (condylomas)
of the lower genital tractDo not integrate into the host genome,
remaining instead as free episomal viral DNA
HPV InfectionHPV Infection
Currently HPV vaccination exist!
GARDASIL®Human Papillomavirus Quadrivalent (Types 6, 11, 16, and 18)
CERVARIX Human Papillomavirus Bivalent (Types 16 and 18)
Persistent HPV InfectionPersistent HPV Infection
Most HPV infections are transient and are eliminated within months by an acute and chronic inflammatory response
Half are persistent at 6 monthsOne third are persistent at 12 months9-20% are still persistent at 24 monthsSome of these progress to cervical
intraepithelial neoplasia (CIN), a precursor lesion from which most invasive cervical carcinomas develop
PathogenesisPathogenesis
HR HPVs express two potent oncoproteins encoded in the HPV genome called E6 and E7
The E6 and E7 oncoproteins bind and inactivate two critical tumor suppressors, p53 and Rb and promote growth and increased susceptibility to additional mutations that may eventually lead to carcinogenesis
Methods for HPV DNA Methods for HPV DNA TestingTesting
Residual material of liquid-based Pap test can be used for detection of high risk HPV DNA
Collection swab can also be used
Methods for HPV DNA TestingHybrid Capture 2
FDA approval 1999, used widely in clinical diagnostics laboratories
CervistaFDA approval 2009 for two tests:Detection of HR HPVGenotype 16 & 18Used in clinical diagnostics laboratories as well
PCR-COBAS 4800FDA approved 2011 for detection and genotyping
16 & 18Currently the only test approved for primary
screening
Key Objective HPV DNA TestingKey Objective HPV DNA Testing
Identify those women who have persisting HR HPV infections and are at risk for developing neoplasia
Women who become HPV DNA negative on follow-up are at low risk for having HSIL
Liquid based cytology or co-collection swab
required (cannot be done on conventional smears)
Clinical utilization of HR HPV DNA Clinical utilization of HR HPV DNA asas adjunct test to the Pap adjunct test to the Pap
Triage of women(>21) with ASCUS resultsPost-treatment surveillance of women with CIN2-3Adjunct to Pap test in primary cancer screening women 30 years or older
The Bethesda System for The Bethesda System for Reporting Cervical CytologyReporting Cervical Cytology
Bethesda System 2014Bethesda System 2014
Specimen AdequacySatisfactory -Sufficient number of well visualized epithelial cells
Unsatisfactory-Too few cells or more than 75% obscured by inflammation, blood
-Unlabeled
Interpretation / ResultInterpretation / Result
Negative for intraepithelial lesion or malignancy
Organisms
Epithelial abnormalities
OrganismsOrganisms
Trichomonas vaginalisFungal organisms morphologically
consistent with Candida sppShift in vaginal flora suggestive of bacterial
vaginosisBacteria morphologically consistent with
Actinomyces sppCellular changes consistent with Herpes
simplex virusCellular changes consistent with
Cytomegalovirus
TRICHOMONADS
CANDIDA SPP
HERPES SIMPLEX
• Squamous Cell• Atypical squamous cells of Undetermined Significance(ASCUS) cannot exclude HSIL (ASC-H)• Low Grade Squamous Intraepithelial lesion (LSIL)• High Grade Squamous Intraepithelial lesion (HSIL)• Squamous Cell Carcinoma
• Glandular Cell • Atypical Glandular cells (AGC) • Endocervical adenocarcinoma In Situ (AIS)• Adenocarcinoma
Bethesda System 2014 Bethesda System 2014 Epithelial Cell Epithelial Cell AbnormalitiesAbnormalities
Cervical Intraepithelial LesionCervical Intraepithelial Lesion
Is the precursor of invasive cancer
LSIL/HSIL/SCCLSIL/HSIL/SCCLow grade squamous intraepithelial
lesion (LSIL)
High grade squamous intraepithelial lesion (HSIL)
Squamous cell carcinoma
INTERRELATIONS OF NOMENCLATURE SYSTEMSINTERRELATIONS OF NOMENCLATURE SYSTEMS
IN PREMALIGNANT CERVICAL DISEASEIN PREMALIGNANT CERVICAL DISEASE
SCJ
Squamous cells
Glandular cells
Superficial cells
Intermediate cells
Endocervical cells
NORMAL PAP
Benign Epithelial Cells
Low-Grade Squamous Low-Grade Squamous Intraepithelial Lesion (LSIL)Intraepithelial Lesion (LSIL)
Features of LSIL/HPVFeatures of LSIL/HPVHPV viruses cause cytopathic changesMorphologic changes that can be
recognized under the microscopeKoilocyte- large cell with large dark
shrunken nucleus and cytoplasmic cavitation
KoilocyteKoilocyte
Features of HSILFeatures of HSIL
Immature cellsEnlarged nuclei, high nuclear to
cytoplasmic ratio (big nucleus/small cytoplasm)
Dark chromatinIrregular nuclear membrane
High-Grade Squamous High-Grade Squamous Intraepithelial Lesion (HSIL)Intraepithelial Lesion (HSIL)
High-Grade Squamous High-Grade Squamous Intraepithelial Lesion (HSIL)Intraepithelial Lesion (HSIL)
Colposcopic Guided Cervical Colposcopic Guided Cervical Biopsy Biopsy for HSIL for HSIL
Mosaic &punctation in colposcopic view CIN 3 in cervical biopsy
Invasive Squamous Cell Carcinoma
Is the most common type of cervical cancer
Features of Squamous Cell Features of Squamous Cell CarcinomaCarcinoma
Keratinized and dense cytoplasmCell pleomorphism: elongated, tadpole, ovalIrregular nuclear size and shapeIndia ink chromatin
Squamous Cell CarcinomaSquamous Cell Carcinoma
Squamous Cell CarcinomaSquamous Cell Carcinoma
Invasive Squamous Cell Invasive Squamous Cell CarcinomaCarcinoma
Ulcerated cervical tumor Cervical biopsy of tumor
Pap Test Glandular Cell Pap Test Glandular Cell AbnormalitiesAbnormalities
Detects glandular neoplams such as Endocervical carcinoma Endometrial carcinomaFeatures of Adenocarcinoma Abnormal glandular cells Variation in nuclear size Irregular chromatin distribution Prominent nucleoli Tumor necrosis
Endocervical Adenocarcinoma
Accounts for 20% of malignant cervical tumors
Atypical Endocervical Glands Atypical Endocervical Glands and Adenocarcinoma in Situand Adenocarcinoma in Situ
Endometrial Carcinoma
Is the most common gynecologic cancer in the USA
ENDOMETRIAL ADENOCARCINOMA
Use HPV co-testing in cancer screening
Approved as screening test in USA 2003In combination with Pap, not approved as
stand-aloneFor every 3-5 years useFor women 30 years old or olderEndorsed by ACS and ACOGA negative HPV test represents a low risk of
developing disease over 5 years and safely allows lengthening of testing intervals
Screening Guidelines ACS-ASCCP-ASCP<21 years: No screening21-29 years: Cytology alone every 3 years30-65 years: - HPV and Cytology every 5 years (preferred) - Cytology alone every 3 years (acceptable)>65 years: No screening following adequate negative
prior screeningAfter hysterectomy: No screening (if no history HSIL) HPV vaccinated: Follow age specific
recommendations (same as unvaccinated women) Am J Clin Pathol 2012:137:516-542
Molecular testing for primary cervical cancer screeningThe Roche Cobas 4800 became the first
HPV test approved by the FDA to replace the Pap test for primary screening of cervical cancer in 2014
The approval allows for HPV testing of women 25 and older and referral to colposcopy if the test is positive for HPV 16/18 and reflexed to a Pap test if positive for HPV but negative for HPV16/18
Guidelines document from ASCCP/SGO pending
Question
Is molecular testing more effective and efficient than co-testing for cervical cancer screening?
HPV TestingThe US Cancer Registry study has found
12.6 % of cervical cancers are either HPV negative or contain rare HPV subtypes
Quality control of HPV test : the internal control is not specific for cervical epithelial cells and could be wrongly deemed adequate
There is not sufficient information to say whether
primary HPV testing trumps co-testing
KEY Points The introduction of the Liquid based Pap improved
accuracy of the testThe Bethesda system simplified the diagnostic categories HPV is common yet it rarely can cause cancer Clinical use of HR HPV detection as an adjunct to the Pap HPV based screening program has been approved by the FDA for the Cobas HPV test in the USA No screening test is perfect The basis of screening requires doing it periodically and repeatedly whether it is a Pap test, co-testing or primary HPV screening