Lab Tour

Our couriers bring the specimens from your doctor’s office to our laboratory.

The specimen(s) and the paperwork are then given a unique ID number which is written on the containers and all of the paperwork.

The ID number is transferred to a cassette which will remain with the biopsy for the remainder of the process.

The specimen is then grossed in. The specimen is measured, inked (so the margins can be identified), cut into thinner pieces, and then placed in the cassette with a lid.

The cassette is then placed in a Tissue Processor. For certain types of tissue this step can be completed with a Microwave Tissue Processor that can reduce the normal 4-8 hour processing time down to about 45 minutes.In either case, the cassettes are run through a series of alcohols, xylene, and finally paraffin (wax) to remove the water from the tissue while leaving the structure undisturbed.

The cassettes are then removed and a Histotechnologist embeds the tissue in a paraffin filled mold. The histotechnologist is a highly trained individual who is able to orient the tissue correctly in the mold so that the slides are prepared with cross sections of the tissue.

The cassette is placed on top of the metal mold so that the specimen is still identified by its unique number. The cassette and mold are then placed on a cold plate to harden the paraffin.

At this point, slides are made on a special printer. The slides also contain the same unique identification number.

When the paraffin is hardened in the mold, the “blocks” are removed from the mold and placed in ice water. A microtome is a specialized piece of equipment that allows the paraffin blocks (and the tissue embedded in them) to be shaved in very thin slices. The cassettes are made to fit into the holder on the microtome. The microtome moves the block past a very sharp blade which slices a VERY thin section of paraffin and tissue from the block. The block is then advanced 3-4 microns and another section is sliced off. As the sections are made, they stick to each other creating a ribbon.

The ribbon is then placed in a warm water bath. The ribbon floats on top of the water and the corresponding slide is then placed under and picks up a section of tissue.

The slides are then dried to remove the excess paraffin. And placed in an automatic stainer. The tissue on the slides is quite clear and translucent so it must be stained to make it easier to see under the microscope. The stains are water based and so the tissue must have the paraffin removed and brought back to a hydrated state. To do this, the stainer places the slides in a series of xylenes, alcohols, and finally water (basically the reverse of the processor). The tissue is then immersed in hematoxylin (purple) and eosin (pink). For preservation, once the tissue is stained the water must then again be removed. The stainer places the slides in progressively stronger alcohols and then xylene.

The slides are then covered with a thin glass or tape covering. Although this can be done by hand, it is much quicker and accurate to have it done by another piece of specialized equipment.

The preparation of the slides is now finished. The slides are placed in special books and given to the pathologist to read. The pathologist looks at the slides under a microscope and interprets the type of disease, if any, is present.

When necessary, the pathologist may order some “special stains” to reach a definitive diagnosis. A very sophisticated piece of equipment is used for these types of stains.

A final report is then created and sent to your doctor. The reports can be delivered by courier, secured web reporting, and/or fax.

The block of tissue and the slides that correspond with it are then filed and kept for at least 10 years.