[Betsy Iole]

CANINE HEALTH FOUNDATION-AKC
OFFICIAL NEWSLETTER. Summer 2005
 
New Study Shows Inherited Links to Canine LYMPHOMA
by Jaime Modiano VMD PhD Colorado Health Sciences Center
 
The lifetime risk & incidence of lymphoma are different among distinct dog breeds, signalling a unique opportunity to identify heritable factors that could be manipulated to reduce the risk. Lymphoma is one of the more common cancers seen in dogs, occuring about 2 to 5 times as frequently in dogs as in people. It is estimated that approximately 1 of every 15 dogs born today will get lymphoma at some point, most likely between the ages of 8 and 11. Lymphomas are cancers that arise from lymphocytes (white blood cells that fight disease). Normally these cells travel through the body in the blood steam and in another network of thin \"tubes\" called lymph vessels, which interconnect organs of the lymphoid system (spleen, lymph nodes, thymus). When a lymphocyte becomes cancerous, it divides out of control and produces large numbers of identical cells, which crowd the lumph nodes and make them swell...

A recently published study supported in part by the AKC Canine Health Foundation showed that the oldest breeds, including Spitz dogs and small Asian \"lap dogs\" share a predisposition for excess lymphomas that arise from cells called T-LYMPHOCYTES suggesting these breeds retain inherited risk factors that arose ancestrally. In contrast, some recently derived European breeds such as Basset Hounds and Cocker Spaniels are predisposed to excess lymphomas that arise from cells called B-LYMPHOCYTES suggesting these tumors may stem from different risk factors....that arose during the process of breed derivation and selection.  Retrievers show an approximately equal number of occurrences of lymphomas [ from both types of cell lines] and in Goldens, each of these tumor types arises from unique genetics characteristics. These exciting results provide the first level of insight that will allow scientists to identify heritable factors that influence the risk of lymphomas in both dogs and people.

[ October 19, 2005, 04:40 PM: Message edited by: Betsy Iole ]

 

[Anonymous]

That was good to know, Betsy. Last year Francis developed a large lump near his right shoulder and when I took him to the vet she said it looked like a lipoma. Immediately I confused it with lymphoma and had a temporary mini-heart attack. After much reassurance I took him home and we've been fine ever since. (Well, sort of fine if you don't mind losing your eyesight)
Thanks.

 

[Betsy Iole]

Interesting that the more "primitive" lymphomas (T-cell) tend to affect the more primitive/older breeds, e.g. spitz type breeds, while the more "differentiated" lymphomas (B-cell) tend to affect the more recently developed breeds.

 

[Barbara Winters]

Very interesting Betsy. I've heard over over the years that certain lines seem to have a predisposition to lymphoma. And almost all of the bassets were around 8 years old. Although I do know of a couple that were around 2 years of age. Wonder if there could be both T cell and the B cell types in the same breed?

 

[Betsy Iole]

I think the piece mentions that the breeds in sort of the middle range of development, e.g. some sporting breeds, have both T and B cell lymphomas.

In humans, lymphoma testing is pretty detailed and lymphoma has at least a couple dozen subtypes that behave differently and respond differently to treatment. Lymphoma diagnosis in dogs isn't quite at the same level. When the researchers talk about T and B cell lymphomas, they're speaking in only the broadest of terms.