[Histonet] carry over

[Glencross Hedley (RW3) CM&MC Manchester]

Hi everyone

I can confirm Nick's scenario, when I was a histology TEQA facilitator, the very first H&E's looked at had some Pap stained cervical cells over the section.

Also, another good source of carry over is the embedding station. If anyone has ever cleaned out wax filled forcep warming blocks (like those on the old Shandon embedder), they will have discovered a treasure trove of tissue pieces! 

On the cytology front, it is very good practice to split gynae & non gynae staining, but also the quality of the non gynae preps can help, by achieving mono layers rather than multilayers. Remember cells stick really well to glass, but very poorly to each other. I wonder if LBC will help? However, if you do get carry over of cervical cells from one smear to another during batch staining, it may be almost impossible to tell. A possible source of false positive cytology and consequent over investigation that is poorly recognised.

Good technique is essential.

Regards

Hedley Glencross
Manchester Cytology Centre UK