|
On Thursday
15th. of July a unique event took place with a Joint Summer Meeting
between the T.V.C.S. and the Northeast Metropolitan & East Anglian
Cytology Society, held at St. Margaret's Hospital, Epping.
This was the result of much effort, in particular by Meetings Secretary
Hasit Patel, who not only managed to organise these joint arrangements,
but put together a meetings programme of exceptional calibre, in
spite of contending with unfortunate last minute changes to the
line-up!
A rather long, arduous walk up-hill from the station was rewarded
by a veritable banquet of home-cooked food, a capacity crowd of
eager cytologists, and an exciting afternoon of lectures.
Borderline
Cytology
The
first talk, entitled 'Borderline Cytology, was presented by Dr
Alistair Deery. He discussed the history of borderline changes
from past 'inflammatory atypias', through the 1986 BSCC recommendations
on recognising 'borderline nuclear abnormality', to the 1994 Joint
Working Party's revision: 'Borderline nuclear changes in cervical
smears: Guidelines on recognition and management'.
In particular, the problems of recognising these cellular changes
were dealt with, as currently it was considered that the borderline
category was open to abuse, being used as a useful place in which
to place all cases that pose a particular diagnostic dilemma to
the cytologist.
Dr Deery emphasised that whenever dyskaryotic changes are recognised
then they must be reported as such, even if a grading as to severity
can not be made. He demonstrated this point by showing a series
of cases which he considered to show features of dyskaryosis but,
following the 1994 Working Party's guidelines, could be classified
as borderline.
Dr Deery also emphasised that more careful consideration should
be given to glandular abnormalities which again may be carelessly
placed into a borderline category when a diagnosis of tubal metaplasia
or even true glandular neoplasia could have been made.
The recognition of true borderline changes still obviously poses
a diagnostic challenge to the cytologist, and the inclusion of any
case into this category should only be made after careful exclusion
from other dysaryotic or benign categories.
HPV Testing
The
second speaker, Dr F. Lorenzato from the Whittington Hospital,
gave an informative talk on 'HPV testing and it's implications
for screening'. Dr Lorenzato gave a brief history of cervical
screening and the role of HPV in the aetiology of carcinogenesis,
particularly as recognised since the advent of PCR testing in 1985.
Identification of HPV subtypes has allowed the identification of
high-risk HPV types such as 16,18,31,33, etc. and these may yet
prove beneficial in cervical screening.
Identification of patients as carriers of these sub-types would
allow them to be placed into a category requiring more frequent
screening, particularly if these patients also presented with borderline
changes in their smears. However it was emphasised that commercially
available assays for HPV typing, based on hybrid capture techniques,
are currently prohibitively expensive for routine use.
Vaccines developed against the E7 antigenic site on the HPV genome,
responsible for blocking major protein synthesis sites such as that
for P53, might also, in the future, help in reducing the incidence
of HPV in the general population.
Quality Assurance
Dr Philip Wilson was next to talk, speaking of his new challenge
as Q.A. Director for the N.H.S.C.S.P. in London. Following a brief
history of quality assurance initiatives within cytology, from initial
proficiency testing schemes to the establishment of a National Co-ordinating
Network, and the later formation of the National Office, Dr Wilson
brought us up to date with the latest developments.
A quality assurance team for gynaecological cytology, covering the
London area, has now been established. This has led to the appointment
of a Q.A. Director and a Q.A co-ordinator, the development of a
Q.A reference centre, and the establishment of Q.A. groups with
professional lead representatives from Cytology and Histology laboratories,
Colposcopy units, primary care establishments, and Health Authorities.
The co-ordinated efforts from all these groups within the Q.A. team
will no doubt provide better primary support for quality control
management, the development of more comprehensive training programmes,
and the careful monitoring of performance at all levels, whilst
also acting as a first point of reference to all those involved
in the screening programme.
ABC2 Guidelines
An excellent meeting was finally rounded off by Dr Amanda Herbert,
who's talk, entitled 'ABC 2: What are the controversies',
had been eagerly awaited. Dr Herbert concentrated mainly on the
controversies that had arisen from the 1995 ABC guidelines and how
these had been re-addressed in the updated ABC 2 guidelines ( still
awaiting publication ).
Three
main areas of controversy had been raised:
1. The significance of transformation zone sampling was discussed.
Cytological identification of the presence or absence of endocervical
cells and/or squamous metaplastic cells was considered not to be
a reliable indicator of TZ sampling but, should be used in conjunction
with other pertinent patient and clinical factors in assessing smear
adequacy; only the smear taker can make a true assessment of complete
TZ sampling.
2. The achievable target ranges for the reporting of each grade
of cytological abnormality was re-assessed.
For the 1995 guidelines, these target ranges had been based on figures
obtained from only 12 screening laboratories. For ABC 2, figures
have been taken from all KC61 returns for all cytology
laboratories within the U.K. In spite of this, the revised achievable
standard ranges were shown to be very similar to those previously
calculated with ranges only being increased slightly:
moderate & severe: 1 to 2%;
mild & borderline: 4 to 9.2 %;
inadequate: 5 to 12.7%
3. The importance of calculation for sensitivity, specificity, and
positive predicative values, both for laboratories and individuals,
was re-emphasised.
It was also noted that the formula for calculating sensitivity of
primary screening, given in the 1995 guidelines, was inaccurate
and had been updated accordingly. Dr Herbert also said that ABC
2 would also re-address the correlation between B.S.C.C. and Bethesda
terminologies, whilst she also hinted that the ABC guidelines may
also hold a couple of further 'surprises' We continue to wait to
see what these may be!
So concluded another extremely enjoyable and informative T.V.C.S.
meeting, with thanks to our colleagues at the Northeast Metropolitan
& East Anglian Cytology Society, to Leica for their sponsorship,...and
to Heinz baked beans who appeared in more than one speaker's presentation!
|