Objective—To assess the usefulness of histologic evaluation of surgical margins to predict local recurrence of cutaneous malignant tumors in dogs and cats treated by means of surgical excision.
Design—Prospective case series.
Animals—40 dogs and 20 cats.
Procedures—60 surgically excised tumors (20 soft tissue sarcomas [STSs], 20 mast cell tumors [MCTs], and 20 carcinomas) were examined histologically. Margins were classified as clean, close, or infiltrated; histologic grade was assessed in STSs and MCTs. Recurrence rates and recurrence-free intervals (RFIs) during a 24-month follow-up period were recorded, and method accuracy was calculated.
Results—Surgical margins were clean in 29 of 60 (48%) tumors, close in 11 (18%), and infiltrated in 20 (33%). Tumors recurred in 27 of 60 (45%) animals, with a mean ± SD RFI of 229 ± 173 days. Recurrence rates for animals that had tumors with infiltrated (16/20) or close (8/11) margins were significantly higher than recurrence rate for animals that had tumors with clean margins (3/29). Margin classification was a significant predictor of RFI. Accuracy of the method to predict recurrence was 94% for carcinomas, 87% for STSs, and 76% for MCTs.
Conclusions and Clinical Relevance—Histologic assessment of margin status was useful for predicting local recurrence of cutaneous malignant tumors in dogs and cats treated by means of excision alone. Method accuracy varied among tumor types and grades. Recurrence times suggested postsurgical follow-up should continue for ≥ 2 years. Results were similar for animals with infiltrated and close tumor margins, and careful postsurgical management is recommended for both.
Objective—To evaluate the pharmacokinetics and clinical efficacy of budesonide in dogs with inflammatory bowel disease (IBD).
Animals—11 dogs (mean ± SD age, 5.7 ± 3.9 years; various breeds and body weights) with moderate or severe IBD.
Procedures—Each dog received a controlled-release formulation of budesonide (3 mg/m2, PO, q 24 h) for 30 days (first day of administration was day 1). The concentration of budesonide and its metabolite (16-α-hydroxyprednisolone) was measured via liquid chromatography–tandem mass spectrometry in plasma and urine samples obtained on days 1 and 8 of treatment. On those days, plasma samples were obtained before the daily budesonide administration and 0.5, 1, 2, 4, and 7 hours after drug administration, whereas urine samples were obtained after collection of the last blood sample. A clinical evaluation was performed on the dogs before onset of drug administration and on days 20 and 30 after start of drug administration.
Results—The highest plasma concentration of budesonide and 16-α-hydroxyprednisolone on day 1 was detected at 1 hour and at 2 hours after drug administration, respectively. After standardization on the basis of specific gravity, the ratio between urinary concentrations of budesonide and 16-α-hydroxyprednisolone was 0.006 and 0.012 on days 1 and 8, respectively. The clinical response was adequate in 8 of 11 dogs.
Conclusions and Clinical Relevance—Budesonide was rapidly absorbed and metabolized in dogs with IBD. The drug gradually accumulated, and there was an adequate therapeutic response and no adverse effects.
Objective—To describe clinical characteristics, treatment, and outcome of dogs with inflammatory carcinoma (IC) and identify patient-, tumor-, and treatment-related factors associated with overall survival time.
Design—Retrospective case series.
Animals—43 client-owned dogs.
Procedures—Records of dogs with a clinical diagnosis of IC that had histologic evidence of dermal lymphatic invasion were reviewed. Data on clinical staging, treatment, toxicoses, response, and survival time were retrieved.
Results—26 (60%) dogs had primary IC and 17 (40%) had secondary IC. Thirty-five (81%) dogs had distant metastases and 2 (5%) had local metastases at the time of initial examination. Six of 29 (21%) dogs had a coagulopathy. Sixteen (37%) dogs did not receive specific treatment for IC, 24 (56%) received medical treatment only, 2 (5%) underwent surgical excision and received medical treatment, and 1 (2%) underwent surgical excision only. Forty-one (95%) dogs had progressive disease, and 2 (5%) had stable disease. Mean survival time for all dogs was 60 days (range, 1 to 300 days). Dogs with a coagulopathy survived a significantly shorter time than did dogs without a coagulopathy (odds ratio, 0.28), and dogs that received medical treatment survived significantly longer than dogs that did not (odds ratio, 2.54).
Conclusions and Clinical Relevance—Results suggested that mammary IC is a biologically aggressive condition in dogs associated with a guarded prognosis. In addition, results suggested that medical treatment may improve outcome, thereby supporting its use in dogs with IC.
Objective—To compare the Kiupel (2 categories) and Patnaik (3 categories) histologic grading systems for predicting the presence of metastasis at the time of initial examination in dogs with cutaneous mast cell tumors (MCTs).
Design—Retrospective case series.
Animals—386 client-owned dogs with cutaneous MCTs.
Procedures—Medical records of dogs with newly diagnosed, histologically confirmed cutaneous MCTs that had undergone complete clinical staging were reviewed for clinical and histopathologic data.
Results—All Patnaik grade 1 MCTs (n = 52) were classified as Kiupel low-grade MCTs, and all Patnaik grade 3 MCTs (43) were classified as Kiupel high-grade MCTs. Of the 291 Patnaik grade 2 MCTs, 243 (83.5%) were classified as Kiupel low-grade tumors, and 48 (16.5%) were classified as Kiupel high-grade MCTs. Dogs with Patnaik grade 3 MCTs were significantly more likely to have metastases at the time of initial examination than were dogs with grade 1 or 2 MCTs (OR, 5.46), and dogs with Kiupel high-grade MCTs were significantly more likely to have metastases than were dogs with Kiupel low-grade MCTs (OR, 2.54). However, 3 of 52 (5.8%) dogs with Patnaik grade 1 tumors, 48 of 291 (16.5%) dogs with Patnaik grade 2 tumors, and 44 of 295 (14.9%) dogs with Kiupel low-grade tumors had metastatic disease.
Conclusions and Clinical Relevance—Findings indicated that in dogs with cutaneous MCTs, prognostication should not rely on histologic grade alone, regardless of grading system used, but should take into account results of clinical staging.