On Wed, 8 Oct 1997, Brent Dorsett wrote:
>
>
> >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
>
>