BRITISH VETERINARY ONCOLOGY STUDY GROUP
Proceedings of Meeting held 11th May 2002
The third meeting of the BVOSG took place On Saturday 11th May at the Yew Lodge Hotel, Kegworth. The topic for discussion, lymphoma.
Thirty members were present to enjoy a well constructed day. Topics for discussion included aetiology and presentation, principles of treatment with cytotoxic agents, cytogenetics and feline lymphoma.
The BVOSG committee of Chairman Malcolm Brearley, Secretary Sue Murphy and Treasurer Ron Lowe, ably took the helm as the day began with aetiology, presentation, staging and diagnosis of canine lymphoma by Dr Laura Blackwood of Liverpool University Veterinary School. It was not long before the discussion turned towards some of the more testing lymphoma diagnoses with a detailed assessment of paraneoplastic syndromes found in canine lymphoma such as hypercalcaemia and hypergammaglobulinaemia. Tumour staging was discussed with some focus on the impact and value of lymphoma staging.
Sue Murphy from the Animal Health Trust was next to take centre stage with an insight into the astonishing potential that lay before us in the technology of cytogenetics. Employing a very clever technique called FISH, alterations in the actual genotype of neoplastic cell lines can be established! A series of thirty cases was presented with clearly demonstrable identical chromosomal alterations among some patients. This work is in its earliest stages in the veterinary context but perhaps here lies the tool with which we may ultimately generate a classification system for lymphoma that enables better indication of prognosis and disease progression? Even better, novel therapeutic strategies may evolve on the basis of knowledge of the specific genetic alterations involved!
The extraordinary potential of cytogenetics based classification was cleverly juxtaposed with the relative limitation of histopathological classification of lymphoma. The extreme complexities of histopathological lymphoma classification were demonstrated by Prof Matti Kiupel. Comparisons were drawn with systems used in the field of human lymphoma and historical attempts to generate working canine classifications in parallel to these were described. The histopathological goal of a working classification giving valuable prognostic and therapeutic information remains elusive. Debate developed as the topic of immunostaining was raised. This technique enables differentiation between lymphoma cells of B and T cell lineage. Prof Corinne Fournel-Fleury drew the debate off course with a beautifully illustrated exposition of lymphoma cytology. Different opinions report that up to 80% of cases of canine multicentric lymphoma can be diagnosed by fine needle aspirate and expert cytologists would even differentiate up to 80% of cases as T or B cell in origin by cytological evaluation alone. Afterwards, the compelling debate about the value of immunostaining as part of a diagnostic protocol for canine lymphoma continued. The key issues presented were the value of obtaining information for subsequent retrospective analysis of disease outcomes versus the impact, or not, of the information obtained on treatment decisions for an individual patient.
A case presentation followed prompting interesting discussion about the decision making process in electing to use chemotherapy in Stage I lymphoma.
After lunch Malcolm Brearley of Davies White Veterinary Specialists very concisely described the principles of therapy with cytotoxic agents. Using basic cell biology and pharmacology he produced a coherent, interesting and practical message. No magic recipes to cure lymphoma once and for all but the power to understand how and why to do the best we currently can.
Time allowed for another interactive case presentation before Dr Andy Sparks of the Animal Health Trust gave an overview of feline lymphoma. The role of FeLV received no small amount of attention. Another issue drawing opinions was that of the possible association between inflammatory bowel disease and intestinal lymphoma.
So, what did we learn?
Lymphoma is not a single disease entity
Current techniques to sub-classify the disease fall short of providing valuable prognostic and therapeutic information.
What lies ahead?
Cytogenetic technology?
Perhaps therein lies the answer to better disease classification and possibly novel therapeutic strategies.