Veterinary clients often seek the same new and innovative cancer treatment options for their companion animals that they read about in the press or on the Internet. It is, therefore, necessary for the practitioner to have an understanding of the development of new and innovative cytotoxic drugs and delivery techniques. This article describes the drug development process and how a new product eventually finds its way into clinical use. Some of the newer drugs and delivery techniques applied to small animals are reviewed.

Membranous ventricular septal aneurysm was diagnosed by echocardiography in 17 dogs and three cats. The aneurysm appeared as a thin membrane protruding into the right ventricle from the margins of a congenital ventricular septal defect (VSD). The aneurysm was intact in nine dogs and two cats and perforated by a small VSD in eight dogs and one cat. Other congenital heart defects were present in seven dogs. In all animals, the aneurysm was an incidental finding observed during echocardiographic examination, and it did not appear to directly cause any cardiac dysfunction.

Combination chemotherapy is superior to single-agent chemotherapy for treating canine lymphoma, but the effect of each drug on efficacy remains unknown. By comparing 34 dogs treated with a modified cyclophosphamide, vincristine, prednisone (COP) chemotherapy protocol and 42 dogs given asparaginase in the induction phase of the same protocol, the effect of asparaginase on the chemotherapeutic protocol was determined. Both groups were compared based on clinical response at 2 weeks and 6 weeks, and on the progression-free interval. Asparaginase did not significantly increase the likelihood of a clinical remission or prolong the initial progression-free interval in the dogs studied.

Twelve eyelid meibomian gland adenomas in dogs were surgically ablated using the carbon dioxide (CO₂) laser. The laser site was not sutured. All procedures resulted in complete removal of the adenoma with no recurrences at 6 months. In addition, no dogs developed corneal disease secondary to the procedure, and the cosmetic appearance of the eyelid margins was good at the end of the 6-month study. Based on results of this study, CO₂ laser ablation of canine meibomian gland adenomas is an effective alternative to standard surgical removal.

Two hundred and forty-four dogs were evaluated for cataracts at the University of Tennessee from January 2001 to December 2002. Fifty-four canine breeds were affected. Odds ratios for cataracts were significantly higher for six purebred dogs (including the cocker spaniel, miniature schnauzer, toy poodle, Boston terrier, miniature poodle, and bichon frise) compared with mixed-breed dogs. One hundred fifty-nine dogs did not have cataract surgery. The most common reason for dogs not having surgery was retinal degeneration (n=66).

Soft-tissue sarcomas are a heterogeneous group of tumors with similar biological behaviors. Wide surgical excision remains the cornerstone of treatment for these tumors. Local recurrence is common following conservative resection, and recurrent tumors are more difficult to treat. Radiation therapy or re-excision with wider margins is indicated if excision is microscopically incomplete. Chemotherapy is often recommended as an adjunctive treatment for high-grade soft-tissue sarcomas because of their higher metastasis rates when compared to low-or intermediate-grade soft-tissue sarcomas. Knowledge of extent of disease and histological grade is helpful in guiding treatment choices.

A 12-year-old, spayed female miniature poodle was evaluated because of a 4-day history of paraparesis, dysuria, and tenesmus. Neurological assessment suggested peripheral nervous system dysfunction, predominantly pelvic limb weakness with a possible concurrent sixth lumbar (L₆) to second sacral (S₂) myelopathy. Further studies supported the diagnoses of myasthenia gravis, hypothyroidism, and meningomyelitis. To the authors’ knowledge, this is the first reported case of concurrent myasthenia gravis and meningomyelitis in the dog. It was unclear whether the identified conditions evolved from a shared etiopathogenesis or were merely coincidental.

Vascular encephalopathy is a commonly encountered clinical complication of infectious endocarditis in humans, but it has been infrequently reported in dogs. A series of four dogs with bacterial endocarditis that subsequently developed acute onset of neurological deficits is described. Clinical signs, diagnostic test results, and outcomes for each case are presented and compared with the human clinical syndrome.

Five dogs from the northeastern United States were presented with clinical signs of neurological disease associated with Rocky Mountain spotted fever (RMSF) infection. Four of the five dogs had vestibular system dysfunction. Other neurological signs included paresis, tremors, and changes in mentation. All of the dogs had an elevated indirect fluorescent antibody titer or a positive semiquantitative enzyme screening immunoassay titer for Rickettsia rickettsii at the time of presentation. Although a higher mortality rate has been reported for dogs with neurological symptoms and RMSF infection, all of the dogs in this study improved with appropriate medical therapy and supportive care.

Combined hydrocephalus, syringohydromyelia, and a ventricular cyst were found by magnetic resonance imaging in a 7-month-old, male miniature dachshund with gait abnormalities and altered mentation. Clinical signs did not improve with prednisone therapy. Ventriculoperitoneal shunting improved the clinical signs and anatomical abnormalities. Repeated operations were needed to replace the ventricular drainage tube at 3 and 31 months after the first surgery. The animal died suddenly with severe tonic-clonic, generalized seizures 3 weeks after the third operation. Ventriculoperitoneal shunting may be a viable treatment for syringohydromyelia associated with hydrocephalus.

Owners are sometimes confused or misinformed about nutritional facts pertaining to pet foods, and three common nutritional myths have been propagated in the popular press. The first myth is that meat by-products are of inferior quality compared to whole meat. The second myth is that feeding trials are unnecessary, and the third myth is that pet food preservatives are bad. This paper examines the known facts related to these three myths and discusses the importance of food trials and the different classes and forms of antioxidants used in pet foods.