The Cytology Laboratory

Chris Faraker

Clinical Cytologist

East Sussex Healthcare Trust

Cytology Staff & Roles• Consultant Pathologists

– HBPC co-ordinates aspects of programme– Report abnormal cytology

• Clinical Cytologists– Often manages laboratory– Report abnormal cytology

• Senior Biomedical Scientists – ‘Checker’ of ? abnormal slides referred– Primary screening

Cytology Staff & Roles• Biomedical Scientists

– Primary screening

– Laboratory practical work

• Cytology Screeners– Primary screening

– Laboratory practical work

• Laboratory Assistants (MLA)– Sample preparation

• Office Staff– Data entry, result entry

Sample Flow

• Samples received by MLA– Checked for labelling/ST number etc– Form and specimen vial bar coded– Sent to BSUH for processing onto slides

• Brighton hub for slide prep for Sussex– ESHT, Worthing & Chichester ? Soon SASH– Could process 120 000 per year

ThinPrep® 3000 Processor

ThinPrep LBC technologyDispersion Collection Transfer

Conventional vs ThinPrep

Sample Processing• ThinPrep 3000 processes up to 60,000 specimens

per year• Racks of 80 vials take approx 2 hours to process.• Places cells onto a slide ready for staining and

screening• T3000 reads each barcode and transfers the

information to an LBC slide for that specimen• Sample integrity• BSUH have two processors

Sample Flow

• Slides returned to Conquest (or other spoke)

• Stained and prepared for screening by MLA

• Request forms data entry (90% ICE) and cytology and histology history printed

• Lab system history or Open exeter

Primary Screening

• By Cytoscreeners and BMSs

• 5 hours max microscopy

• Expect 5 000 to 8 000 per person per year

• Can report negative and inadequate samples

• Identify and mark suspect cells

• Pass ? abnormal slides to ‘Checker’

Abnormal Slides

• ‘Checker’ confirms abnormality and gives opinion

• ‘Checker’ may overrule screener and report as negative

• Passes confirmed abnormals to consultant reporter for final report

Internal Quality Control

• All negative and inadequate slides re-examined by another cytologist

• A ‘quick’ rescreen to check for abnormal cells missed in the original primary screen.

• Method developed in Hastings and Brighton in early 1990’s

• In 1995 became mandatory method of QC for NHSCSP laboratories

Results

• Paper copy sent to surgery or clinic

• Electronic reporting from lab system to surgery computer

• Electronic transfer of all results to PCSS

• PCSS sends result letters to women the next day

Colposcopy Direct Referral

• Reports recommending colposcopy sent automatically to colposcopy secretary

• Women should be seen in colposcopy:– within 8 weeks for borderline and mild

dyskaryosis– within 4 weeks for moderate and severe

dyskaryosis– within 2 weeks for ? Invasive or glandular

abnormality

Laboratory Failsafe of Colposcopy Referral

• Check one month after referral that woman has been offered or has attended colposcopy (we have access to colposcopy database)

• If not, enquiry made to colposcopy secretary

• Further check made at month four. If still no attendance we require letter from colp sec returning woman to GP care

14 Day Turnaround

• Previous target 80% in 4 weeks 100% in 6 weeks

• 14 days from sample collection to receipt of result

• A ‘vital sign’ from Jan 2011

14 Day Turnaround• Delays in Surgery

• Holding on for transport• Inadequate completion of data – sample returned

• Delays in Laboratory• Staff shortage• Delay caused by outside processing

• Delays at PCSS• Incorrect recall given

• All – Long bank holidays• Next – HPV testing

14 Day TurnaroundCervical LBC Received to Report 2010

565

0 0 0 2 3 0 0 0 1 7 5

316

0 0

74.3

100 100 100 99.9 99.9 100 100 100 100 99.7 99.8

85.2

100 100

0102030405060708090

100

Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul

Perc

ent R

epor

ted

0

100

200

300

400

500

600

Num

ber U

nrep

orte

d

Number reported after day 14 Percent reported within 14 days

14 Day Turnaround

Procedures implemented

Double 4 day bank holiday

14 Day Turnaround

ESHT Audit of Rejected Tests 2010

• 195 of 13 200 rejected due to labelling errors or omissions (1.5%)

• 50% of these had no ST number• The rest:

– Unlabelled vial – will be reported inadequate and no slide will be made

– Missmatch of details – DOB, Name etc

– Insufficient information on form or vial– Vial -Name & DOB at least

– Form- Name DOB Address at least + NHS number if possible

ESHT Rejected Test Audit Jul 10 – Jun 11

• Returned for correction 68

• Returned for ST number 49

• Unlabelled vial (discarded) 67

• Total 184

0.74% of 25 000 samples

Request Forms

• Preferred requesting method is by ICE– Patient data linked to pathology system– Can scan forms for quicker data entry– ST number is a mandatory field– Cx visualised 5x360 sweep mandatory field

• Next preferred is OE prepopulated forms

• Least is blank handwritten forms

Technically Inadequate Samples• Rate fluctuates: 1.6% to 2.6% over last 18 months• No longer too thick, airdried or distorted • But:

– Excess blood in the vial– Too many polymorphs– Not enough cells– Blocking of filter

– Lubricant– Cervical mucus– ?Pessary etc

Conquest Inadequate Cytology

Conquest Quarterly KC61 Part B data

2.6

3.6

1.9 1.9

2.5 2.62.4

1.6

2.3

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

apr-jun 09 jul-sep 09 oct-dec 09 jan-mar 10 apr-jun 10 jul-sep 10 oct-dec 10 jan-mar 11 apr-jun 11

Inadequate

Increase reprocessing af ter this

point

Unsat no 360 & Cx vis started in

MayLetter Re: switching to ICE request

forms in J an

Laboratory Quality Assurance

• Cytologist screening sensitivities• Monitored quarterly

• % of abnormal slides correctly detected at primary screening as assessed by rapid review

• NHSCSP Target• All abnormals more than 90%• High grades more than 95%

Laboratory Quality Assurance

All grade sensitivities(4 qtrs rolling data)

80

85

90

95

100

Screeners 99 99 99 99 100

100 98 98 98 9899 99 98 96 969899 99 99 98 9897 97 97 96 96

Laboratory 98 98 98 97 98

2nd qtr 10 3rd qtr 10 4th qtr 10 1st qtr 11 2nd qtr 11

Laboratory Quality Assurance

• Cytologist abnormal cytology detection rate– Percentage of high and low grade abnormalities

detected over 6 months– Drop in rate may indicate screening errors

Laboratory Quality AssuranceConquest

Quarterly KC61 Part B data

1.2 1.1 1.10.8 0.9

1.10.9 1.1

0.7

4.9

4.1 4.04.4 4.3

3.73.9

3.3 3.4

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

apr-jun 09 jul-sep 09 oct-dec 09 jan-mar 10 apr-jun 10 jul-sep 10 oct-dec 10 jan-mar 11 apr-jun 11

High grade

Low grade

Laboratory Quality Assurance

• Positive predictive value– reflects accuracy of a high grade report– percentage confirmed by biopsy

• NHSCSP target range 74.2 – 90.3 %

• Conquest 2009-10 87.8 %

Laboratory Quality Assurance• External quality assessments

– ‘Test’ held twice yearly– Consultants, biomedical scientists &

cytoscreeners– Mandatory participation– Set of 10 slides per round– Consultants must grade abnormality if present– Others must differentiate normal, abnormal and

inadequate– Marking system – action taken if performance

substandard

Laboratory Quality Assurance

• EQA of staining – four times per year

• CPA accreditation– 2 day inspection of standards, quality systems

and performance– A requirement for NHSCSP laboratories

• QARC visit (inspections)– Laboratory and colposcopy standards

Human Papilloma Virus

• Over 100 subtypes – most do not cause disease• Non oncogenic types 6, 11,42, 43, 44 (& 7 others)

cause – Exophytic warts– condyloma acuminatum

– Flat warts– koilocytotic atypia, flat condyloma, borderline cytology and mild dyskaryosis

• Oncogenic types 16, 18, 31, 33, 35, 36 and others cause cervical neoplasia (CIN, CGIN, Carcinoma)

HPV Testing• To start 2011/2012 (i.e. before next April)• Sept 1st 2011 NHSCSP announced which technology

may be used • One testing centre for ESHT, WSHT, BSUH and SASH

• 1st year low grade cytology triage• 2nd year Test of cure

HPV Triage

• Only 15-20% of women with LG cytology require treatment– (ESHT data 2009-2010: 24% referred to

colposcopy with LG cytology had CIN 2 or worse)

• High Risk HPV testing would identify those in this group at risk of cervical neoplasia

HPV Triage

• If HR HPV negative then return to 3 yearly recall – 30% expected to have this outcome

• If positive then refer to colposcopy

• 46% of first borderlines and 83% of mild dyskaryosis are HR HPV positive

• 20% of those referred will require treatment

Test of Cure

• Follow up for HG CIN and CGIN is currently 10 years

• HR HPV test 6 months after treatment– Negative (even with LG cytology): low risk of

residual neoplasia so routine 3 yearly recall– Positive or with HG cytology : colposcopy

• 75% of treated women returned to routine recall following TOC

Reporting and Follow up of Abnormalities

(prior to HPV testing)

• Management– Most regress but 21% (Conquest 2009-10 data)have high grade CIN– Repeat in 6/12 on first & second– On third refer for colposcopy– No more than 3 over 10yrs without referral– ‘High grade borderline’ 49% (Conquest 2009-10 data)

have high grade CIN• - immediate referral

• Routine recall after 3 negative FU smears

Borderline squamous

Mild Dyskaryosis • After one mild dyskaryosis 40% of women have high

grade CIN (one study) • (Conquest 2009-10 data 25% referred for mild had CIN2+)• Regression to normal after one mild is 25%.

• Management (local at present – may change)– Repeat in 6 months on first– Colposcopy on second– Referral on first if following treatment for CIN

• Routine recall after 3 negatives

Normal Cervix

HPV effect and Mild DyskaryosisCIN 1

• Moderate & severe dyskaryosis• Predicts presence of CIN2 or CIN3 or worse• Additional features may suggest carcinoma• Management

– 1/3 of CIN3 become cancer in 10 years– Urgent colposcopic referral– ESHT direct referral system– FU post LLETZ – negative smears over ten years

before return to routine recall – Test of cure

High grade squamous dyskaryosis

CIN 3 extending into glands

Severe Dyskaryosis

Invasive squamous carcinoma

Glandular neoplasia

• Endocervical cell dyskaryosis– In situ (CGIN) or invasive

• Manage as CIN3 if in-situ except FU samples must include endocervical cells.

• FU is best carried out in Colposcopy clinic (NHSCSP 20)• Test of Cure not applicable to CGIN

• Endometrial adenocarcinoma• Ovary, Tube etc

Endocervical dyskaryosis and CGIN

Ovarian carcinoma

Vault Cytology (not part of the screening programme PCSS will not

issue results or recall women)• On normal recall and no CIN in hysterectomy – no vault

cytology• NOT on normal recall and no CIN in hysterectomy – one

vault cytology at 6 months then stop• Histology shows CIN fully excised – vault cytology at 6

and 18 months• Histology shows CIN incompletely or uncertainly excised

– follow-up as if cervix still in situ ie 10 years for HG, 2 years for LG

• Cervical cancers – as directed by gynaecologist• Non cervical cancers – no vault cytology

Endocervical brush• An endocervical brush must never be used alone.

It may be used in addition to the Cervex Brush in the following circumstances only:– There is difficulty inserting the Cervex Brush into a

stenosed os

– The woman is being followed up for borderline changes in endocervical cells

– The woman is being followed up for treated glandular abnormality (CGIN) and a previous sample was inadequate due to the absence of endocervical cells

• Place both samples in a single vial