Table 31.6 Preparation of Cell Blocks
Thomas Jefferson University Hospital cytology
laboratory cell block and Shandon megawell preparations
for fine-needle aspirates
University of Rochester
standard cell block procedure
Pour collection fluid with specimen into a 50-mL centrifuge
Centrifuge entire specimen at 750 rpm.
Spin down specimen to achieve a
concentrated cell button at 2400 rpm.
Decant supernatant into separate tube and place aside for
Pour off su pernata nt.
Retain sediment for cell block.
Add 5 cc of buffered formalin.
Prepare a biopsy bag or blue tissue paper by placing it on a
paper towel (this is performed under a biologic safety hood).
Spin to fix specimen at 2400 rpm.
Let specimen sit in formalin.
After sitting in formalin, remove hard-
ened cell button from centrifuge tube
with metal spatula and gently loosen
the edges of cell button until it breaks
free of centrifuge tube.
Cut cell button into cross-sections and
place on blue histology tissue paper
moistened with buffered formalin.
Wet the blue tissue paper (or biopsy bag) with a small amount
of 10% buffered formalin solution and place sediment (tip up)
on the blue filter paper or the biopsy bag.
Fold the filter paper to secure the specimen. Label the side and
the front of the cassette with specimen accession number and
Fold tissue paper around cell block
section(s) and place in histology
cassette (remember to label
histology cassette with appropriate
nongynecologic accession number
and patient's name).
Folded edges of the blue tissue paper
should face UP.
Place the specimen into the cassette and carefully close the top
to prevent crushing the specimen.
Place the closed cassette in a container of buffered 10% forma-
Snap cassette shut and place in white
specimen cup containing buffered
Use enough formalin to cover cas-
Deliver to the histology laboratory for preparation.
Cell blocks are submitted to histology
laboratory by 5:00 p.m. each day.
Centrifuge the decanted supernatant at 750 rpm.
Decant the supernatant.
Label a Shandon megawell slide with accession number.
Assemble the disposable Cytospin chamber and the labeled
Place the assembled chamber with slide in the spin bucket of
the Shandon cytocentrifuge.
With a pipette, transfer the sediment from the 50-mL centrifuge
tube to the megawell chamber assembly (when transferring
specimen, use the sediment in its entirety—a smaller aliquot
may be used based on the thickness of the material).
Balance the spin bucket with a balancing assembly.
Seal the lid of the bucket.
Spin the specimen at 750 rpm.
Remove the assembled chamber from the cytocentrifuge.
Disassemble the slide carefully to prevent disruption of the