Thames Valley Cytology Society

Volume 5 Issue 1
January 2002

 

Cervical Cytology - ThinPrep Morphology

Report by Sami Turgman, Wexham Park Hospital

 

At the TVCS Watford Meeting 10 November 2001,Nick Dudding, from the regional cytology training school (Leeds), was the first speaker of the morning session. He listed the advantages and disadvantages of LBC and gave his thoughts on applying liquid based ctyology to cervical smears. He described the appearance of the different types of normal and dyskaryotic cells and of some of the common infectious organisms found in smears. His talk concentrated on morphology.

He thought that, recently, more negative comments have been made with regard to LBC. He himself is not sure of the value of the method after the initial enthusiasm. It is interesting that in Scotland the Scottish Office does not want it but the staff do, whilst in England it is the opposite.

Nick then listed the following the advantages to the screener:

  • with thin prep the area for screening is smaller about 19mm/12mm.contiaing 50,000-70,000 cells per smear.
  • the smear is cleaner,with less blood and polymorphs, flatter but not monolayer,
  • fewer fields.

He went on and categorised the appearances of the various types of cells and organisms as

  1. Almost identical to the conventional smear - e.g. organisms, koilocytes, mild dyskaryosis and endocervical cells.
  2. Similar - e.g. endometrial cells, atrophy, squamous metaplasia, repair and squamous carcinoma
  3. Quite different - e.g. severe dysk and CGIN.

This was followed with transparency of candida, actinomyces and herpes. Actinomyces is not as good as that identified on the conventional smear (no spider legs), but Herpes is excellent on the thin prep due to the good preservation.

The transparencies demonstrating mild desk and kilobytes were very good and still appear in groups as most low grades. The endocervicals are slightly smaller , more crowded and hyperchromatic. You need to look more closely by using the high power in the case of endometrial cells. An example of CGIN showed cells with a well preserved prominent nucleoli. Christine Page of Newport made the comment that the features of GCIN still there although they do look different on the thin prep.

Nick then reminded the audience that single cells showing severe dysk are difficult to pick at the low power and more emphasis on this at the training schools will help prevent serious misses. Examples of microbiopsies were also shown.

The next topic was on the inadequte smear. Using ThinPrep, inadequates score 0.5% in Scotland. However it raises the question of getting a seemingly adequate smear from an inadequate sample. An imcreased emphasis that smear takers should be properly trained is necessary if this techniques is implemented.

Toward the end of the talk few members of the audience made different comments some these as follows:

  • After screening thin prep smears for the last ten months I do find them now quite tiring
  • How do you judge the smear as inadequate.
  • Borderline figures did not go down.
  • There are problems with CIN 3 and metaplastic cells.
  • I am happy to go back to the conventional smears.
  • Why do we have to change?
  • Nick Dudding thought that most screeners like it so why not give to them.

Finally when the question of cost was mentioned, Nick added that in Scotland 16 of the general practices like the thin prep method so much that they pay for the kits themselves. Also, a deal will be worked out as the NHS will be baying the kits in large bulks.
The audience found Nick Dudding's talk very interesting, stimulating and full of good humour it was a good start for this bright saturday morning.