large cell lymphoma
Brent Dorsett (brentd@nyct.net)
Wed, 8 Oct 1997 17:33:30 -0400 (EDT)
>Viki Mosiman
>Robert H Lurie Cancer Center
>Flow Cytometry Core Facility
>Northwestern University Medical School
>Chicago, IL
>vlm646@nwu.edu
>
>I am interested in an opinion on the best way to detect Large-cell
>lymphoma(B Cell type) in lymph nodes.
>
>We currently disaggregate nodes then surface stain using
>45/19/kappa/lambda. Although
>we often have success ,there are cases where clearly the node is a
>malignant B-cell lymphoma by morphology in Surgical Pathology but we see
>no evidence in Flow. We have tried blocking with fetal calf and mouse
>serum. We have tried different gating strategies such as 45ss combined
>with 19ss gating or combined with fs. We have tried different staining
>combinations -19/5/kappa/lambda-45/19/10/kappa&45/19/10/lambda. We have
>tried live dead assays(7AAD) combined with surface staining in case a node
>was necrotic. Someone even suggested injecting nodes with PBS to express
>cells instead of mincing and grinding lymph nodes(they thought this might
>be a more gentle process).
>
>We don't seem to have the same problem with other malignant lymphomas in
>lymph nodes,just with the diagnosis of Large-cell lymphoma ( B-Cell type).
>Any suggestions would be greatly appreciated. Thanks for your help!
>
>Clinical Flow Lab
>Northwestern Memorial Hospital
>
>
Viki,
Recently we have seen several cases where the malignant population in large
cell lymphomas was extremely difficult to demonstrate in flow. One, a lymph
node, was easily demonstrated by immunohistology to consist of large numbers
of B cells infiltrated with reactive T cells. In flow cytometry after the
usual mechanical disaggregation, suspesion in RPMI 1640 + 5% FCS, filtering
through 100 micro nylon mesh and washing almost no malignant B cells could
be detected. The second was a FNA of a mass in the liver collected into RPMI
1640. This too immunostained positively as large B-cells, but in flow was
composed of 99% small to medium T-cells. Cell viability was good in both
preparations but there appeared to be substantil very small debris. I'm
guessing that these large cells were particularly fragile -- although the
appearance of the FNA cells in histology seemed normal. I would be
interested in the experience of other with large cell lymphomas.
Brent Dorsett
Special Pathology Laboratory
Lenox Hill Hospital
NYC