"Prostatic Neoplasia" TUMOR TIDBITS, A BIWEEKLY VETERINARY ONCOLOGY E-LETTER Volume 3; Number 9; March 8, 2002. Editor: Kevin A. Hahn, DVM, PhD, Dipl - ACVIM (Oncology) & Overall Nice Guy! ====================================================== THIS WEEK'S TUMOR TIDBIT: PROSTATIC NEOPLASIA OVERVIEW OF WHAT'S IN THE TEXTBOOKS: * Prostate adenocarcinoma is a malignant tumor occurring with equal frequency in castrated and intact male dogs. It is highly metastatic to the regional lymph nodes, lungs, and skeleton (lumbosacral area and pelvis most often). SIGNALMENT * Primarily medium-to large-breed, intact or neutered male dogs * Median age on examination, 9-10 years * Rare in cats SIGNS * None in some animals * Tenesmus and ribbonlike feces * Stranguria, dysuria, and urinary incontinence * Hind limb lameness, lethargy, and exercise intolerance * Anorexia * Prostatomegaly-- firm, asymmetrical, and immobile * Pain in some animals * Sublumbar lymphadenomegaly in some animals DIFFERENTIAL DIAGNOSIS * Other primary or metastatic neoplasm * Acute or chronic prostatitis * Benign prostatic hypertrophy * Prostatic cysts DIAGNOSTIC RESULTS * Inflammatory leukogram * High ALP activity * Hematuria, pyuria, and malignant epithelial cells * Thoracic and abdominal radiography--pulmonary nodules or diffuse increase in interstitial markings indicate metastatic disease. Sublumbar lymphadenomegaly, mineralization within the prostate, and lytic lesions to the lumbar vertebrae or pelvis are common signs. * Prostatic ultrasonography-- focal to multifocal hyperechogenicity with asymmetry and irregular outline of the prostate; intraprostatic mineralization in some animals * Contrast cystography--may help differentiate prostatic disease from urinary bladder disease * Prostatic biopsy * Prostatic wash or aspirate--may recover cells with criteria of malignancy. Interpret with caution if inflammation is observed. TREATMENT * Prostatectomy if local disease only. Success of prostatectomy depends on the skill of the surgeon and extent of disease. * Castration may provide temporary decrease in rate of growth or partial remission. Most tumors are not androgen responsive. * Radiotherapy may palliate bone pain. * Pain relief and supportive care are the main thrust of treatment. * Stool softeners and high-fiber diet may decrease tenesmus. * Carboplatin, cisplatin, and doxorubicin are potentially beneficial. PATIENT MONITORING Ability to urinate and defecate, pain secondary to skeletal metastases, and quality of life PREVENTION/AVOIDANCE * Castration does not prevent disease POSSIBLE COMPLICATIONS * Urethral obstruction * Metastatic spread to skeleton (lumbar vertebral bodies), lungs, and lymph nodes EXPECTED COURSE AND PROGNOSIS * Grave prognosis * Survival, 1-3 months WHAT DO WE DO AT GULF COAST? * First, the goal of therapy is not for cure, but for control. This means that there are many innovative approaches for use of radiation and chemotherapy to manage this disease. * Second, quality of life, in essence non painful urination, is the most important goal for treatment. * Our approach is a combination of radiation (once every 14 days for 3 times) for palliation of pain, combined with Mitoxantrone chemotherapy (every 2 weeks for 5 times) along with daily Piroxicam therapy. * In our experience, the majority of dogs are managed well, have significant relief of symptoms, and survive within a range of 3 to 12 months, averaging 9 months. Don't hesitate to call or email us at Gulf Coast Veterinary Oncology! ALL THE BEST AND HAPPY NEW YEAR, Kevin A. Hahn, DVM, PhD Diplomate ACVIM (Oncology) & Overall Nice Guy Gulf Coast Veterinary Specialists 1111 West Loop South, Suite 150 Houston, TX 77027 P: 713.693.1166 F: 713.693.1167 http://www.gcvs.com mailto:drhahn@gulfcoastvetspec.com