Dear Charles - If your samples are so soft that you have to turn up your microns in order to section them, then the tissue is underprocessed. Many people make the mistake of equating "underprocessed" with "under fixed". A quick way to see the level of processing is to add 50.mls of 1% Alcoholic Eosin to the 2nd 100% Alcohol on the processor. It will make no difference in later staining, but you will be able to see the level of dehydration by the level of Eosin absorbed. The Eosin will show as a red tint throughout the tissue after facing, if the dehydration is complete. If the dehydration is incomplete, you will see a red tinged ring around the outside edge of the tissue in a faced block. It there is inadequate dehydration, then you can't expect to see adequate clearing with Xylene or infiltration with paraffin, therefore - underprocessed. Our procedure for breast excision biopsies is as follows: Breast specimens are grossed in at receipt, and sectioned into cassettes. Cassettes sit for 1 day in clean formalin before processing overnight We use a Tissue-Tek VIP 5, with pressure/vacuum on each step 1 10% Neutral Buffered Formalin 37˚C yes 1hr, 30min 2 10% Neutral Buffered Formalin 37˚C yes 1hr, 30min 3 70% Alcohol 37˚C yes 30 min 4 95% Alcohol 37˚C yes 40 min 5 95% Alcohol 37˚C yes 45 min 6 100% Alcohol 37˚C yes 1 hr 7 100% Alcohol 37˚C yes 1 hr 8 100% Alcohol 37˚C yes 1 hr 9 Xylene 37˚C yes 45 min 10 Xylene 37˚C yes 45 min 11 Paraffin 58˚C yes 1 hr 12 Paraffin 58˚C yes 1 hr, 30 min 13 Paraffin 58˚C yes 2 hr 14 Paraffin 58˚C yes 2 hr The key factor is the quality of the gross sections. Sections must be no larger than a nickel. Certainly no thicker. The rule of thumb is that if the gross tissue touches one side of the cassette, then it must not touch the other. There must be room for solutions to circulate freely within the cassette, surrounding the tissue. Thick cut tissue is the curse of the processing. I hope this helps. Terri L. Braud, HT(ASCP) Anatomic Pathology Supervisor Laboratory Holy Redeemer Hospital 1648 Huntingdon Pike Meadowbrook, PA 19046 ph: 215-938-3689 fax: 215-938-3874
9. Processing of breast tissue (Charles Riley) ------------------------------ Message: 9 Date: Tue, 5 Jan 2016 08:59:49 -0500 From: Charles Riley <cri...@dpspa.com> We have been experiencing some issue lately with cutting our breast excisions. Recently we had two specimen where after our 8 hr run the tissue was still extremely soft. Our medical director said the fat sectioned beautifully but the fibrous tissue appeared cooked. Can anyone give a suggestion as to how we should process our breast excisions from grossing through to microtomy sectioning. Currently I have tried to get grossing to limit the specimen to 2mm by 2mm by 1mm thick. We run an 8hr process using the Thermo Shandon Excelsior processor. We cut our sections at 4um but have recently had to do them at 6um in order to get the soft samples cut. -- Charles Riley HT(ASCP)CM Histopathology Coordinator/ Mohs Doctors Pathology Services, Dover DE _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
