Half-body radiotherapy in the treatment of canine lymphoma.

In a Phase I-II study, half-body radiotherapy was used to treat 14 dogs with multicentric lymphoma. Using this technique, a radiation dose of 7 Gray (Gy) was delivered to one half of the body in a single exposure. The other half of the body was treated approximately 28 days later. Of 14 treated dogs, 11 (79%) had a measurable decrease in tumor size. Five dogs achieved a complete or partial remission with a mean duration of 102 and 54 days, respectively. In predicting response to therapy, poor prognostic factors included large tumor burdens, advanced disease stage, and chemotherapy-resistant tumors. Side effects of treatment were divided chronologically into acute (radiation sickness, tumor lysis), subacute (bone marrow suppression), and chronic (radiation pneumonitis, lymphoma-cell leukemia) syndromes. Complications were more severe in tumor-bearing dogs when compared with healthy control animals. Dogs with small tumor burdens and minimal internal disease had fewer complications compared with those with more advanced disease.

Half-body radiotherapy. Evaluation of the technique in normal dogs.

Eight healthy mongrel dogs were treated with half-body irradiation (HBI) in a pilot study to evaluate the technique and radiotolerance of different organs. Cranial and caudal half-body fields were established using the 13th thoracic vertebra as the dividing point. Under general anesthesia, either 7 or 8 Gray (Gy) were delivered to one half of the body using opposing radiation portals. The other half of the body was similarly treated 28 days later. The dogs were monitored for 12 months. Significant radiation effects included transient bone marrow suppression and radiation sickness. There were no serious or life-threatening problems, but the 8 Gy group consistently showed more severe clinical signs and histologic changes than the 7 Gy group. Total body irradiation in two fractions of 7 or 8 Gy given 1 month apart appears to be a safe treatment that can be developed for therapy in veterinary oncology.

Canine bladder and urethral tumors: a retrospective study of 115 cases (1980-1985).

One hundred and fifteen dogs with neoplasms of the lower urinary tract (bladder and/or urethra) were retrospectively evaluated at five referral institutions participating in ongoing studies by the Veterinary Cooperative Oncology Group. Most tumors were malignant (97%) and of epithelial origin (97%). Lower urinary tract tumors were more common in older dogs weighing greater than 10 kg. The following significant (P less than 0.05) statistical associations were found using the University of Guelph hospital population as control; there was no sex predisposition although the female:male ratio was 1.95:1. Neutered dogs were predisposed as were Airedale Terriers, Beagles, and Scottish Terriers, whereas German Shepherds were significantly under-represented among dogs with lower urinary tract tumors. These statistical associations should be interpreted cautiously because of possible demographic differences in hospital populations among the University of Guelph and other cooperating institutions. There were no significant correlations between age, gender, weight, breed, response to therapy, and survival time. Clinical signs were indicative of lower urinary tract disease and included hematuria, stranguria, and pollakiuria. The laboratory data were nonspecific except for urinalysis test results. Hematuria and inflammatory urinary sediments were most commonly reported; neoplastic cells were identified in the urine sediment of 30% of dogs with lower urinary tract tumors. Contrast cystography was a useful noninvasive diagnostic method since 96% of the dogs had a mass or filling defect in the lower urinary tract demonstrated by this technique.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of cyclophosphamide-induced hemorrhagic cystitis in five dogs.

Sterile hemorrhagic cystitis developed in 5 dogs after treatment with cyclophosphamide. Four dogs were being treated with various antineoplastic protocols, and the fifth dog had recurrent immune-mediated thrombocytopenia. In all instances, clinical signs of hematuria and stranguria persisted after cyclophosphamide administration was discontinued. Three dogs required cystotomy to remove necrotic mucosa and calculi. The other 2 dogs were treated with intravesicularly administered dimethyl sulfoxide to decrease inflammation and to inhibit fibroplasia of the bladder wall. In 4 dogs, clinical signs resolved after treatment. The fifth dog, treated surgically, continued to have intermittent urinary incontinence attributable to residual bladder wall fibrosis.

Collateral ligament injury and stifle luxation.

Isolated collateral ligament injury is uncommon in dogs and cats and often occurs concurrently with injuries to other stifle ligaments. These injuries are either treated with primary reconstruction of the individual ligaments or with transarticular pin or splint stabilization of the joint until adequate periatricular fibrosis is achieved. Prognosis is generally good if adequate joint stability has been achieved.

Diseases of the nose and sinuses.

This article discusses the diagnosis and management of acute and chronic diseases of the nasal cavity and sinuses. Also discussed are the anatomy of the upper respiratory tract, guidelines for obtaining a thorough history and performing a complete physical examination, and various diagnostic procedures, such as rhinoscopy, culture, and serology.

Surgical therapy of canine nasal tumors: A retrospective study (1982-1986).

The results of surgical therapy in 15 dogs with histologically confirmed nasal tumors were analyzed retrospectively and compared to previous reports. Median survival time for all dogs was seven months. When adjusted for nontumor-related deaths, median survival increased to nine months. These values are two to three times longer than previous reports. To determine possible prognostic indicators, tumor stage, location, and histological type were compared to survival time. Dogs with unilateral nasal tumors had a median survival of 11 months, as compared to three months for dogs with bilateral tumors (p = 0.005). Tumor stage and histological type were not significant factors in comparing survival times.

Problems in wound healing associated with chemotherapy and radiation therapy.

Chemotherapy and radiation therapy are combined with surgery to treat locally invasive, nonresectable, or potentially metastatic tumors. The goal of combination therapy is to decrease the tumor burden with cytoreductive surgery so that residual tumor cells are more sensitive to adjuvant therapy. Adjuvant chemotherapy or radiation therapy is most beneficial when given in the immediate perioperative period. However, surgical wounds are also susceptible to growth inhibition by these agents. This chapter reviews the potential problems associated with surgery in the cancer patient and the effect of chemotherapy and radiation therapy on wound healing.