"Canine Breast Tumors" TUMOR TIDBITS, A BIWEEKLY EMAIL NEWSLETTER FROM GULF COAST VETERINARY ONCOLOGY Number 95; April 4, 2003. ======================================================================= THIS WEEK'S TUMOR TIDBIT: Canine Breast Tumors ======================================================================= What's the best approach for managing breast cancer in dogs? There are many reports over the past 25 years describing surgical procedures and survival outcome. Likewise there are many biological studies evaluating tumor size, histological variant, hormonal receptivity and other factors in an attempt to predict surgical prognosis. In the latest report, provided in this month’s Journal of Veterinary Internal Medicine, Drs. Philibert and others at Purdue University published the results of a study to evaluate if specific host factors, such as age at diagnosis, obesity, and hormone status, influence the prognosis of canine mammary gland carcinomas and to confirm if previously reported risk factors (ie, histologic subtype, tumor size, and World Health Organization [WHO] stage) were important in a large series of affected dogs. Ninety-nine female dogs with mammary gland carcinomas, no previous therapy, an excisional biopsy, and known cause of death were studied. No significant association with survival was noted for age at diagnosis (chronologic or physiologic), obesity, or hormone status (ie, spayed versus intact, regardless of time of being spayed). Of the tumor factors analyzed, those that would predict a shorter survival time included histologic subtype anaplastic carcinoma (P = .02) or evidence of metastasis at the time of diagnosis (P = .004). The only factor that would suggest a longer survival time in dgos with breast cancer would be those dogs having a tumor size of 3 cm or smaller (P = .005). Dogs that were classified as having tumor-related mortality had a shorter postoperative survival compared to dogs that died of other causes (14 months versus 23 months; P = .03). In conclusion, histologic subtype, WHO stage, and tumor size remain important prognostic factors in canine mammary gland tumors. Further study of other prognostic factors is needed to determine which tumors are adequately addressed with local therapy only and which dogs may require adjuvant treatment with chemotherapy. ======================================================================= As always, we hope this info helps and don't hesitate to call or email us Gulf Coast Veterinary Oncology! Kevin A. Hahn, DVM, PhD, Diplomate ACVIM (Oncology), drhahn@gcvs.com Janet K. Carreras, VMD, Diplomate ACVIM (Oncology), drcarreras@gcvs.com Glen K. King, DVM, MS, Diplomate ACVR (Radiology & Radiation Therapy), drking@gcvs.com Gulf Coast Veterinary Diagnostic Imaging & Oncology 1111 West Loop South, Suite 150, Houston, TX 77027 P: 713.693.1166 F: 713.693.1167 W: www.gcvs.com ======================================================================= Copyright © 2003, Gulf Coast Veterinary Oncology