HPV Testing Uses and Abuses

Barbara S. Apgar, MD, MS

Professor of Family Medicine

University of Michigan Medical Center

Ann Arbor, Michigan

Objectives

• Understand the current uses of HPV testing.

• Discuss when HPV testing is or is not indicated.

• Compare the sensitivity of HPV testing and cervical cytology for cervical cancer screening.

Progression to Invasion

Persistent positivity with oncogenic HPV types is uncommon but required for progression

Cervical cancer

Apgar, Brotzman, Spitzer

Sigurdsson K et al. Int J Cancer 2007;2682-2687.

HPV Types in CIN 2, CIN 3 and Cervical Cancer,

Iceland, 1990-1994 and 1999-2003

#2

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1

Hybrid Capture 2: FDA approved

• Low risk HPV types

• 6, 11, 42, 43, 44

• High risk HPV types

• 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68

Triage, management and co-testing should be

by HR HPV types only

Methods to detect HPV DNA

• Pooled mixture of probes for high-risk HPV types:

• 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68 + 66.

• Does not distinguish individual types.

• Polymerase chain reaction.

• Molecular amplification method identifying a small amount of a target DNA.

• Identification of specific type of HPV.

FDA-approved HPV DNA tests

• Hybrid Capture 2 HPV DNA Assay (13 pooled)-Quigen

• HPV types: 16, 18, 31, 33, 35, 39, 45, 51, 52,

• 56, 58, 59, 68.

• HPV detected by chemiluminescence

• Cervista HPV HR (14 pooled).

• Same HPV types as HC 2 + HPV type 66.

• Cervista HPV 16/18.

• HPV type-specific test (genotyping).

FDA-approved HPV tests

• cobas 4800 HPV test. (approved 2011)-Roche

• PCR-based.

• 14 HR HPV types.

• Genotyping for HPV 16 and 18 integrated into the assay.

• Concurrently detects remaining 12 types as a group.

Aptima HPV test (GenProbe)-FDA 2013

Detects E6/E7 mRNA expression of 14 HR HPV types

Approved for testing on Hologic system.

HPV E6/E7 overexpression: necessary condition for the start and progression of cervical neoplasia.

E6 and E7 inactivates p53 and pRb suppressor proteins.

Is correlation between HPV mRNA and CIN 3 a true biomarker of risk?

94% and 100% of women with CIN 3 and cancer were + for E6/E7 mRNa activity. (Castle et al. Clin CA 2007;13)

HPV mRNA detection

• HPV mRNA detection may improve specificity.

• It is unknown which lesions will regress or progress.

• Increased monitoring needed.

• Detection of mRNA transcripts may allow clinicians to know whether or not HPV is actively replicating E6 and E7 oncogenes.

• Bottom line: May be able to stratify risk of progression to CIN 3 in women with abnormal cytology.

Brown AJ et al. Best Prac Res Clin OG 2012;26:233

HPV tests for detection of CIN 2 and 3 Cuzick J et al. Br J Cancer 2013;108(4):908-913

• HPV tests should be FDA approved or supported by peer-reviewed published data on sensitivity and specificity.

• Performance should be similar to assays used in clinical trials.

• Tests should have documented clinical performance characteristics (92% +/- 3% sensitivity for CIN 3+)

• > 85% specificity in screening setting.

Saslow D et al. ACA Cancer J Clin. 2012;62(3):147-72.

Stoler MH et al. Am J Clin Pathol. 2007;127(3):335-7.

Home brewed HPV assays

• Some molecular labs have developed their own HPV assays.

• Usually PCR-based.

• Problem: cut-offs are not clinically validated.

• Not FDA-approved.

• What does a positive or negative result actually mean? Exercise caution!

HPV DNA Testing

Areas of clinical utility

Co-testing with cervical cytology in women > 30.

• Assess the risk of recurrence/persistence after treatment of CIN 2,3 (cotesting).

• “Preferred” option for ASC-US triage because of cost and predictive value.

• “Acceptable” option for LSIL triage in postmenopausal women.

HPV testing not recommended

• Routine screening in women < age 30 (except ASCUS triage).

• Women > 24 years with ASC-H, LSIL, HSIL, AGC (except postmenopausal LSIL reflex HPV testing).

• Women considering HPV vaccination.

• Routine STI screening.

• As part of sexual assault workup.

HPV Genotyping

Both DNA and mRNA tests available

Prognostic information seems similar.

5 year risk of CIN2+ if HPV 16 = ~10%

Risk of CIN2+ is lower if HPV 18 , but there is association for adenocarcinoma.

Bottom line: ASCCP guidelines show genotyping acceptable without recommending for or against use

Allows for clinician discretion and patient choice

2013 ASCCP management guidelines

Wright TC, et al. J Lower Genital Tract Disease, 2007; 11: 201-222 and 223-239

Comments on HPV genotyping

• Not recommended yet: Women with ASC-US.

• Cotesting.

• Genotyping triages cytology negative, HPV 16/18+ to colposcopy.

• Colposcopy is indicated for all women with HPV+ ASCUS regardless of genotyping result.

• Threshold for colposcopy exceeded by both groups.

Are guidelines being followed?

• Estimated that > 50% of the 75 million US Pap tests performed in 2010 in the US were:

• Outside guideline compliance.

• Therefore, unnecessary.

• More anxiety in woman with negative Pap and HPV + results than in woman with normal Pap and unknown HPV status.

Solomon D et al. CA Cancer J Clin 2007;105.

Kitchener HC et al. Int J Gynecol Ca 2008;18

Berkowitz Z et al. Obstet Gynecol 2010;116.

2010 CDC survey of IM, FP, ObGyn 950 Pap test providers

• Primary outcomes were responses to clinical case vignette of a 35 year old woman who had cervical cancer screening.

• Negative Pap and + HPV test (co-testing).

• Questions: when to do the next Pap and HPV test? Adherent with guidelines or not?

Berkowitz Z et al. Obstet Gynecol 2010;116.

Results of 2010 CDC survey

• > 80% of all physicians reported that HPV DNA testing with Pap has higher sensitivity than Pap alone.

• 35 year old: negative Pap and + HPV test.

• 54% recommended HPV test at the same time as the Pap (adherent with guidelines).

Conclusions of 2010 CDC Survey

• About 50% of women > 30 years did not receive recommended management of Pap negative, HPV+ cotesting.

Knowledge of HPV tests - CDC

• 12% of clinicians did not know there was a high

risk and low risk HPV test.

• 56% of clinics use high risk tests only.

• 25% use both high and low risk HPV tests.

• Bottom line: low risk HPV testing adds cost without

additional value to health care.

High and low-risk HPV testing reported by clinical specialties

0

10

20

30

40

50

60

70

Family Practice Int Med ObGyn Mid-level

High risk HPV

High and low risk HPV

Lee, Berkowitz, Zahava, Saralya. OG 2011;118:4-13

Low risk HPV testing

• Screens for non-oncogenic HPV types.

• Serves no purpose in the context of cervical cancer

screening.

• Low risk testing should not be performed for genital

warts. Does not change management.

• Bottom line: + low risk HPV test is clinically

insignificant but …..unnecessary follow-up is not.

Why order low risk HPV tests?

• Clinician confusion.

• It is on the lab req as a check-box option.

• Financial gain to clinician or clinic or institution.

• Low and high risk HPV billed the same (doubles the cost.

• Test marketing by industry.

• 2007: 45% of labs offered low risk HPV testing. (Arch Pathol Lab Med 2008;132)

• Need attributed to reimbursement and demand.

Requests to check HPV status

• Direct to consumer advertising associated with significant increases in HPV test use by clinicians. (Price et al. Med Care 2011;49.)

• Screening for HPV status outside cervical cancer screening should be avoided.

Value of co-testing women < 30 yrs

• 50 % of clinicians and clinics do HPV co-testing in women < 30 years (not adherent).

• % of clinicians doing co-testing for this age group doubled since 2004.

• Despite significant rate of transient HPV infections in this age group.

• Problem: Women < age 30 referred to colposcopy after co-testing.

Other issues with co-testing

• About 6% prevalence of women with discordant results will require additional follow-up.

•

• Problems:

• Repetition of co-testing annually or biannually rather than triannually.

• Repeating co-testing < 3 years if new sexual partner.

Berkowitz Z et al. Obstet Gynecol 2010;116.

Castle PE et al. Obstet Gynecol 2009;113. Katki HA et al. Lancet Oncol 2012; 12: 663

Katki HA, et al. Lancet Oncol 2012; 12: 663

Proportion of Co-Test Results in

331,061 Kaiser women > 30 years

92.5%

2.4%

3.7% 1.4%

Discordant

Kaiser Study

N=331,818 women > 30

years in prospective co-

testing study

Katki HA, et al. Lancet Oncol 2011;

12: 663

Cumulative Risk Of Invasive Disease

Based on Initial Co-Test

Conclusions of CDC Report 2011

• Many clinicians report guideline-adherent HPV testing.

• Some also report inappropriate HPV testing (no clinical indication).

• Low risk HPV testing (33%).

• HPV co-testing in women < age 30 (60%).

• Consequences: increased medical costs, unnecessary follow-up tests, patient anxiety and alarm about HPV status.

Why use HPV testing for detection of CIN 2,3 and cancer?

Increased sensitivity of carcinogenic HPV testing for detection

of CIN 2,3 and cancer.

Increases the efficiency of cervical cancer screening by better

risk stratification than cytology alone.

Necessary role of persistent carcinogenic

HPV infections in the development

of serious lesions

Finding carcinogenic HPV types

does not

provide a diagnosis of CIN 3 or

cancer

It identifies a group of women in

whom CIN 3+ is more likely

Compensation for the limitations of

cytology, colposcopy, histology

Relied on repeated annual

or

biennial Pap screening

Used CIN 2 as a threshold for

treatment to provide an

additional margin of safety

even though CIN 2 can regress

Adopted an expanded role for the

detection of carcinogenic HPV DNA

in the clinical management of

cervical abnormalities

Triage of Postmenopausal Women

with LSIL

62 year old postmenopausal woman

with atrophy.

LSIL cytology. No HPV testing.

Always normal Pap tests.

HPV testing in postmenopausal women with LSIL and no HPV test?

• Prevalence of CIN 2,3 drops with increasing age.

• Accuracy of LSIL as a marker for HPV drops in older women.

• Postmenopausal women can be managed less aggressively than premenopausal women.

• ASCCP: No HPV test: Acceptable options include reflex HPV DNA testing, repeat cytology at 6 and 12 mos. and colposcopy.

Postmenopausal women with LSIL

• If the HPV is negative or no CIN identified at

colposcopy, repeat cytology in 12 months.

• If either the HPV test is + or repeat cytology is >

ASCUS, colposcopy.

• If 2 consecutive repeat cytology tests are

negative, routine screening.

There is something new on the horizon

Photo courtesy of Alan Waxman, MD

What happens to HPV after tx for CIN 2,3 ?

• Most women become HPV negative after treatment of CIN 2,3 provided recurrent/persistent disease not present.

• Women who fail treatment have high rates of HPV positivity.

• HPV testing has high negative predictive value.

• Useful in post-treatment surveillance.

HPV follow-up after treatment CIN 2.3

Systematic review Paraskevaidis et al. Ca Treatment Rev 2004;30:205-11

Treatment Outcome

HPV status Success Failure

n=672 n=204

Negative 84% 17%

Positive 16% 83%

Clearance of HPV after treatment for CIN 2,3 or persistent CIN 1

Moore et al. Obstet Gynecol 2011;117:101-108

1207 treated women prospectively studied.

Treated LEEP, cone, or laser ablation.

Followed with colpo, cytology 2-6, 12

months after tx, then annually until HPV

cleared.

Genotyping done.

45% had laser ablation

55% had excision.

Time to clearance of HPV

HPV types No. with HPV type at baseline

No. (% cleared) Median time to clearance (months)

HPV 16 418 387(93) 5.9

HPV 18 99 96(97) 5.9

HPV 31 149 142(95) 5.4

HPV 39 89 79(89) 6.3

Almost all women with HPV types 16, 18 had clearance and 50%

cleared within 6 months.

Moore et al. Obstet Gynecol 2011;117:101-108

HPV testing post-tx predicting residual disease in subsequent TAH specimens n=115

Sensitivity Specificity Accuracy*

Resection

Margin 75% 53% 61%

HPV Testing 85% 67% 73%

Predictive value of resection margin was much improved when used

in combination with HPV DNA testing

Park JY et al. Obstet Gynecol 2009;114:87-92