Robert, we're not currently doing lumpectomies, but we have recently done 32 whole prostate glands and counting, so here's what we're doing in that regard, as some of the equipment and processes could be useful in your situation.
We cut on the Leica RM2255 automated microtome. We obtained their Super Mega Cassette Clamp, (part no 140502 38967). This clamp mounts easily onto the microtome, and holds SurgiPath SuperCassettes (Cat No VSP59067B-BX grey in colour). The beauty of this microtome is that the stroke is 10 mm longer than our previous Reichert-Jung microtomes, I believe it is 70 mm vertically. In terms of slides, we had some on hand, from Fisher and other mfgrs, that are 75x38, 75x50, 75x80 mm, with coverslips that are 35x50, 45x50, and 48x65, whatever will hold and cover the tissue, depending on each specimen. The slides go on our automated stainer, held diagonally with other slides to keep them vertical, and coverslipped by hand.
In terms of processing for these sections, we use our normal overnight processing cycle as we would for our routine surgical blocks. These sections are well-fixed before processing, cut at 4-5 mm during grossing. Having said that, breast is a whole different ball game than prostate, and section thickness is going to be more critical, and probably more of a challenge to achieve, and you might adopt a processing protocol that has some steps extended, since your specimen won't be as homogeneous as a prostate gland, i.e. fatty areas, solid/fibrous areas.
It would be interesting to learn about these diagnostic excisional lumpectomies. Like the prostates, I presume it is to give the pathologist a better picture of what is going on in a larger area than will fit on a standard slide?
I should add that I learned a lot about this topic on the Histonet, which helped a lot in developing our method!
Hope I have been of help in turn. I'd also be interested in opening this topic up to other organs that are being sectioned elsewhere in a MACRO way.
Eric Gagnon MLT
Kingston General Hospital
Kingston, Ontario, Canada
Histonet mailing list