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
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Samples received by MLA
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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
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ESHT, Worthing & Chichester ? Soon SASH
Could process 120 000 per year
ThinPrep® 3000 Processor
ThinPrep LBC technology
Dispersion 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
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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 reexamined 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 Turnaround
Cervical LBC Received to Report 2010
100 100
100 565
85.2
90
74.3
80
70
Double 4 day bank holiday
316
60
50
40
14 Day Turnaround
Procedures implemented
30
20
10
7
2
3
5
0
0
0
0
0
0
1
0
0
0
Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul
Number reported after day 14
Percent reported within 14 days
600
500
400
300
200
100
0
Number Unreported
Percent Reported
100 100 100 99.9 99.9 100 100 100 100 99.7 99.8
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
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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
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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
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
• High grades
more than 90%
more than 95%
Laboratory Quality Assurance
All grade sensitivities
(4 qtrs rolling data)
100
95
90
85
80
2nd qtr 10
3rd qtr 10
4th qtr 10
1st qtr 11
2nd qtr 11
Screeners
99
99
99
99
100
98
99
98
98
98
96
98
96
Laboratory
100
99
98
99
97
98
99
97
98
99
97
98
98
96
97
98
96
98
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 Assurance
Laboratory Quality Assurance
• Positive predictive value
– reflects accuracy of a high grade report
– percentage confirmed by biopsy
• NHSCSP target range
• Conquest 2009-10
74.2 – 90.3 %
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)
Borderline squamous
• 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
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
CIN 1
HPV effect and Mild Dyskaryosis
High grade squamous dyskaryosis
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Moderate & severe dyskaryosis
Predicts presence of CIN2 or CIN3 or worse
Additional features may suggest carcinoma
Management
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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
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