Question about Pathology "slides"

[Summergirl]

Hi everyone, I have a question regarding biopsy "slides". How is tissue handled at a lab-such as: when one hospital wants to see the original biopsy tissue what is the procedure that the lab follows? Do they send the actual slides they looked at or do they keep tissue and make new slides when requested?

I hope that doesn't sound like a dumb question! My Mom has had brushing and washing samples from a bronchoscopy sent from the original lab, then to Mayo, then to Emory. I was just wondering how this is actually done.

And then, when the pathologist looks at them, are cancer cells defined by how they look under a microscope, or how they react to chemicals, or what? If by sight, can cancer cells look like other types of cells, or do they have their own distinct "look".

Wow, too much watching CSI! It's never as easy as it is on CSI!

Thanks!

Kelly

[Guest DaveG]

Tissue is preserved by several methods. When the tissue is processed for microscopic examination, pices of the tissue is embedded in a block of parafin. The block of parifin is then placed in a machine, that looks very similar to a meat cutter (I have no other way to describe it, so forgive me if it sounds awlful). This slicer has the abililty to slice sections of the parafine block, along with the tissue, at microthin slices. The slices are floated in ice water and the tech will biring a microscope slide up on the slice and pick it up with the slide. The slice then is attached to the slide through a quick heat. The slide, with the slices of tissue, then goes through a system of stains, which is a very time consuming procedure.

Finally the slide is ready to be read.

First the slide is screened by a Cytotechnologist, who has been highly trained to be able to distinguish healthy cells from unhealthy cells. If the cytotechnologist sees nothing but normal cells, a normal report is made. Unusually many slices will be taken from the piece of tissue, so there may be many slides from the same piece of tissue. All these slides are examined. A diagnosis is not made on the basis of one slide or one piece of tissue. Usually many pices of tissue will be taken and submitted for pathological review. These pieces of tissue are also examined macroscopically, by the eye, looking for abnormal appearing tissue.

Tissue can also be microscopically examined in a matter of minutes through a procedure know as a frozen section. Rather then embedding the tissue in parafin, which takes some time, the tissue is frozen using liquid oxyden and hydrogen. While it is frozen, it is placed in that same microslicer. Again very thin slices are taken from the tissue and mounted on a microscope slide and go through a rapid staining procedure. This is a fairly accurate procedure and is done on most cases where cancer is involved with a surgical procedure. It is from the frozen section report, which is usually returned to the surgical suite within 30 minutes or less, as to how the surgeon will then proceed.

By law all these tissue samples, slides, and parafin blocks must be stored for a specific period of time, which may vary from state to state. Usually the minimum time that these are stored is ten years.

I am presently being evaluated for a clinical study. For this study. my oncologist has requested the tissue samples from my original surgery in October 2001. The last I heard, they have already obtained the samples and those have been sent off to the drug company for evaluation.

Storage of these samples, slides, etc, can be very critical for many reason, some of which may be for legal issues. The method in which these are mainrained and stored are in accordance with local and federal laws.

I hope I have answered your question. As you see, it is not exactly easy to answer with just a few sentences. I was a med lab tech in the Army for several years before I cross trained into Nuclear Medicine. I worked for a short while in cytotechnology and pathology. I left after several months of having to assist with autopsies. I enjoyed the lab work, but the autopsies got to me.

[betplace]

Wow,

That was fascinating David! Thanks for the very clear explaination.

Blessings

Betty

[Summergirl]

Wow Dave G., thanks so much for that description. I had all kind of scenarios in my head about how they handle these tissue samples, so just was not sure what happens.

Thanks so much!

Kelly