Clinicopathological findings and results of bone marrow aspiration in dogs with cutaneous mast cell tumours: 157 cases (1999-2002).

Bone marrow aspiration for routine staging of canine cutaneous mast cell tumour is not consistently performed, and the overall incidence of bone marrow infiltration and predictive value of the complete blood count (CBC) is unknown. This study evaluated a series of 157 dogs presented for cutaneous mast cell tumours in which a CBC and bone marrow aspiration were performed. The incidence of bone marrow infiltration at initial staging was low at 2.8%, and 4.5% overall. Factors significantly associated with bone marrow infiltration included increased age, leucocytosis, anaemia, neutrophilia, monocytosis, eosinophilia, thrombocytopenia, being purebred and staging at the time of recurrent or progressive disease. Our study suggests that a bone marrow sample is not indicated for routine staging but maybe indicated for those dogs with mast cell tumours having either an abnormal haemogram (neutrophilia, monocytosis, eosinophilia, basophilia, anaemia and thrombocytopenia) or presenting for tumour regrowth, progression or new occurrence.

Feline leukemia virus. Immunization and prevention.

Our understanding of the pathogenesis of FeLV infection is little changed from what was described by Hardy and his colleagues in the mid-1970s. The prevention of FeLV infection consists, first, of avoiding the agent and, second, of providing optimum immunologic resistance. In multi-cat environments, the former is achieved through test-and-removal methods perennially reviewed in the literature and by minimizing exposure to outdoor cats. The latter is possible by attempting to maintain a low-stress, pathogen-free household and by the use of appropriate, effective immunization programs. Simple immunologic concepts used for the development of vaccines against feline distemper and rabies have evolved to enable generation of products that can now protect against retroviruses. The use of more complex biologic methods, such as recombinant technology and the manipulation of antigen presentation, bears encouragement, so that perhaps one day the most destructive of feline infectious diseases may be checked.

Evaluation of L-asparaginase: polyethylene glycol conjugate versus native L-asparaginase combined with chemotherapy. A randomized double-blind study in canine lymphoma.

L-asparaginase is an enzyme that inhibits protein synthesis by the depletion of sources of L-asparagine, which is necessary for transformed lymphoid cells to proliferate. L-asparaginase is used in the treatment of childhood acute lymphoblastic leukemia. A problem with L-asparaginase therapy is the immunogenicity of the enzyme and the development of anaphylactic reactions. Canine lymphoma is a predominantly B-cell tumor with widespread disease; without treatment, dogs with lymphoma usually survive 1-2 months. Canine lymphoma will respond to L-asparaginase therapy. A randomized double-blind study evaluated a polyethylene glycol (PEG) conjugate L-asparaginase combined with chemotherapy (vincristine, cyclophosphamide, doxorubicin, and prednisone). Thirty-five dogs were randomized to the PEG L-asparaginase group, and 34 dogs were randomized to the native L-asparaginase group. Thirty dogs (85.7%) achieved a complete remission (CR) with a median time to relapse of 217 days, and 32 (94.1%) dogs in the native L-asparaginase group achieved a CR with a median time to relapse of 214 days (P greater than 0.05). The asparaginase was well tolerated in both groups. Two dogs in the native L-asparaginase group had severe allergic reactions, and one dog in the PEG asparaginase group had a generalized urticarial reaction after repeated injections. This study indicates that PEG L-asparaginase has equal therapeutic efficacy to native L-asparaginase.

The zoonotic potential of feline leukemia virus.

The many studies that have addressed the possibility for FeLV infection in human beings are reviewed in this article. Because of the many similarities between FeLV-induced immune system impairment in cats and retrovirus related acquired immune deficiency syndrome in man, these two conditions are discussed as well.

Suppurative colitis in a cat.

A young cat with chronic large bowel diarrhea was found to have suppurative colitis. Treatment with sulfasalazine resulted in prompt clinical improvement, although histologic abnormalities persisted. Three months later, the cat was euthanatized because of effusive feline infectious peritonitis. Histologic examination revealed a normal colon.

The management of feline lymphosarcoma.

Lymphoma may occur in almost any site, in a cat of any age, in either a FeLV-infected or uninfected animal. As the most common tumor type found in this species, LSA should be included in the differential diagnosis for virtually any clinical problem in any body system. For the unusual forms of this malignancy, just as for the more common types, the prognosis and response to cytotoxic therapy is generally based on the pretreatment volume and location of the tumor, as well as on the overall status of the cat. Dramatic differences have been noted in the sensitivities of some of the various forms of LSA to conventional chemotherapy. Recognizing these differences and managing our patients and their owners accordingly should make the treatment of this disease far more rewarding.

Zoonotic diseases of cats.

As veterinarians, our responsibilities do not end with the care of our patients. The welfare of our clients and their families depends on our ability to detect and control potentially zoonotic diseases in their pets. Because some of these zoonoses can have devastating effects on the development of the unborn fetus or on family health in general, discussion about these diseases between veterinarian and client is often emotionally charged. Under such circumstances, the offering of inaccurate and erroneous information by the veterinarian can have drastic consequences. It is likely that other zoonotic diseases of domestic pets will be identified in the future, especially those that can cause opportunistic infections in debilitated and immunodeficient persons. In the meantime, the potential hazards of cat ownership can be significantly reduced through an increased understanding of feline diseases and an improved level of health care for our feline patients.

Mandibular resection for removal of oral tumors in 30 dogs and 6 cats.

In 30 dogs and 6 cats with oral tumors involving the mandible or soft tissues adjacent to the mandible, the tumors were removed by mandibular resection. The most common tumors in the dog were malignant melanoma (10 cases; 33%) and squamous cell carcinoma (8 cases; 27%). The most common tumor in the cat was the squamous cell carcinoma (5 cases; 83%). Thirteen dogs (43%) were evaluated as locally tumor-free at a median follow-up of 15.4 months. Local recurrence of tumor and/or metastasis was evident in another 10 dogs (33%). Four of the 6 tumors in the cat recurred within 8 months.