General Research Areas & Studies
- Angiogenesis
- Feline Lymphosarcoma
- Feline Mammary Tumor Study
- Melanoma Study
- Proliferation Indices
- Immunophenotyping
Angiogenesis is an essential component of metastasis, providing the principal route by which tumor cells exit the primary site and enter the circulation. Vascular endothelial growth factor (VEGF), angiogenin (ANG) and basic fibroblast growth factor (bFGF) play pivotal roles in tumor growth and metastasis.
The main objectives of this prospective study are two-fold: first, to validate the use of an enzyme-linked immunoabsorbant assay (ELISA) test kit for detecting plasma angiogenin and basic fibroblast growth factor in dogs, and second, to evaluate VEGF, ANG and bFGF levels in dogs with a variety of malignancies over a defined therapeutic period to determine the significance of levels in response to therapy and progressive disease.
We are currently validating assays for canine ANG and bFGF. The VEGF assay has been previously validated for use in dogs. Results of this study may enable clinicians to utilize levels of these angiogenic factors as a noninvasive way to monitor a patients response to therapy or early relapse. Angiogenic factor analysis may also allow for the design of clinical trials using newly developed angiogenesis inhibitors.
This is a retrospective study that will include all cats with gastrointestinal LSA diagnosed with a biopsy in the last 5 years. Biopsies will be re-evaluated and classified as small cell, intermediate cell, or large cell lymphomas. Immunohistochemistry will be done to further classify LSA as B-cell or T-cell. Parameters evaluated will include response to chemotherapy, remission duration, survival times in relation to LSA cell size and type.
This study seeks to answer if and how much reproductive/hormonal status increases the risk of breast cancer in female cats. In human and dog breast cancer, studies show that hormonal/reproductive status plays an important role in prognosis, prevention, and treatment of disease. In dogs, a study similar to this one showed an increased risk of breast cancer correlated with the age at which a dog was spayed in its life. A more recent study also showed that dogs that were spayed around the time of diagnosis of mammary cancer enjoyed potentially improved survival as well.
This is a case-control study, and we have sent questionnaires to obtain information about spay status and the use of progestins for 330 cases of feline mammary cancer diagnosed through the biopsy service in 2000-2001. We have also sent similar questionnaires for almost 400 randomly selected, age-matched controls that had dermal biopsies submitted to the biopsy service during the same time period (2000-2001). We will compare results from the two groups to determine the importance of hormonal/reproductive status for feline mammary cancer. This data will be added to more detailed, descriptive information already acquired for over 200 cats diagnosed with mammary cancer from 1996-98.
Canine oral melanoma is both highly metastatic and locally aggressive. Previous studies have evaluated various treatments of the primary tumor but have not addressed treatment and prevention of microscopic metastatic disease. Even with excellent local treatment and no evidence of metastasis at diagnosis, most diagnosed dogs (70-85%) still die from melanoma. This study seeks to determine if the addition of adjuvant chemotherapy to the treatment regimen would improve survival for patients diagnosed with early-stage melanoma. This study is multi-institutional and has been approved by the Veterinary Cooperative Oncology Group (VCOG).
Patients included in the study have been diagnosed with oral melanoma, and, at the time of diagnosis, staging revealed no evidence of distant metastasis. All cases have undergone adequate treatment (surgery +/- radiation therapy) of local and regional disease. From this group of patients, we are comparing progression-free and overall survival in dogs that received additional treatment with systemic carboplatin to those that were not. Preliminary results (VCS 2001) indicated a positive difference in overall survival. We are currently seeking funds to cover the costs of chemotherapy for a prospective study.
In addition, we are evaluating the ability of prognostic markers, such as the proliferation indices (Ki-67, AgNORs, and PCNA), to improve the information used to make treatment decisions. These indices can potentially be used as indicators of the aggressiveness of tumor behavior. Predictive value has been improved through the use of these markers in other tumor types, such as in canine cutaneous melanoma.
- Used to evaluate the number of cycling cells per total number of cells
- Indices include mitotic index, AgNORs, PCNA, MIB-1 (ki-67)
- Retrospective on the cases from previous study
Inclusion:
–Dogs without distant metastatic disease at diagnosis based on routine staging
–Dogs with biopsy available for review
–Dogs treated with surgery to completely remove the tumor +/- radiation therapy for residual microscopic disease
–Dogs not treated with any other form of treatment until recurrence at any site
