OBJECTIVE To evaluate effects of anatomic location, histologic processing, and sample size on shrinkage of excised canine skin samples.
SAMPLE Skin samples from 15 canine cadavers.
PROCEDURES Elliptical samples of the skin, underlying subcutaneous fat, and muscle fascia were collected from the head, hind limb, and lumbar region of each cadaver. Two samples (10 mm and 30 mm) were collected at each anatomic location of each cadaver (one from the left side and the other from the right side). Measurements of length, width, depth, and surface area were collected prior to excision (P1) and after fixation in neutral-buffered 10% formalin for 24 to 48 hours (P2). Length and width were also measured after histologic processing (P3).
RESULTS Length and width decreased significantly at all anatomic locations and for both sample sizes at each processing stage. Hind limb samples had the greatest decrease in length, compared with results for samples obtained from other locations, across all processing stages for both sample sizes. The 30-mm samples had a greater percentage change in length and width between P1 and P2 than did the 10-mm samples. Histologic processing (P2 to P3) had a greater effect on the percentage shrinkage of 10-mm samples. For all locations and both sample sizes, percentage change between P1 and P3 ranged from 24.0% to 37.7% for length and 18.0% to 22.8% for width.
CONCLUSIONS AND CLINICAL RELEVANCE Histologic processing, anatomic location, and sample size affected the degree of shrinkage of a canine skin sample from excision to histologic assessment.
Objective—To examine buffy coat smears for circulating mast cells in clinically normal cats and cats with illnesses unrelated to mast cell tumors and identify whether conditions other than mast cell tumors are associated with mastocytemia in cats.
Animals—40 clinically normal cats and 40 cats with diseases unrelated to mast cell tumors (all cats were client owned).
Procedures—A blood sample for a CBC, serum biochemical analyses, and buffy coat evaluation was obtained from each cat. Ill cats underwent other testing on the basis of their disease process.
Results—No mast cells were detected in any sample. Eosinophilia was evident in 11 (27.5%) and 12 (30%) clinically normal and ill cats, respectively. Basophilia was identified in 4 (10%) and 8 (20%) clinically normal and ill cats, respectively. Eight of the 40 (20%) ill cats had neutrophilia.
Conclusions and Clinical Relevance—Circulating mast cells were not identified in clinically normal cats or ill cats without mast cell tumor–related disease. Ill cats did have conditions that caused eosinophilia, basophilia, or neutrophilia. The absence of mast cells in buffy coats obtained from clinically normal and ill cats lends support to the current practice of buffy coat evaluation for tumor staging and follow-up examinations in cats with mast cell tumors. Further studies of buffy coat analysis in cats with different forms of mast cell tumors are indicated to specifically elucidate the test's prognostic value for those patients.
Objective—To compare the detection of pulmonary nodules by use of 3-view thoracic radiography and CT in dogs with confirmed neoplasia.
Design—Prospective case series.
Animals—33 dogs of various breeds.
Procedures—3 interpreters independently evaluated 3-view thoracic radiography images. The location and size of pulmonary nodules were recorded. Computed tomographic scans of the thorax were obtained and evaluated by a single interpreter. The location, size, margin, internal architecture, and density of pulmonary nodules were recorded. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for thoracic radiography (with CT as the gold standard).
Results—21 of 33 (64%) dogs had pulmonary nodules or masses detected on CT. Of the dogs that had positive CT findings, 17 of 21 (81 %) had pulmonary nodules or masses detected on radiographs by at least 1 interpreter. Sensitivity of radiography ranged from 71 % to 95%, and specificity ranged from 67% to 92%. Radiography had a positive predictive value of 83% to 94% and a negative predictive value of 65% to 89%. The 4 dogs that were negative for nodules on thoracic radiography but positive on CT were all large-breed to giant-breed dogs with osteosarcoma.
Conclusions and Clinical Relevance—CT was more sensitive than radiography for detection of pulmonary nodules. This was particularly evident in large-breed to giant-breed dogs. Thoracic CT is recommended in large-breed to giant-breed dogs with osteosarcoma if the detection of pulmonary nodules will change treatment.
OBJECTIVE To characterize long-term elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate (CI-CSH) beads in vitro by comparing 2 distinct sample collection methods designed to mimic 2 in vivo environments.
SAMPLES 162 CI-CSH beads containing 4.6 mg of carboplatin (2.4 mg of platinum/bead).
PROCEDURES For method 1, which mimicked an in vivo environment with rapid and complete fluid exchange, each of 3 plastic 10-mL conical tubes contained 3 CI-CSH beads and 5 mL of PBS solution. Eluent samples were obtained by evacuation of all fluid at 1, 2, 3, 6, 9, and 12 hours and 1, 2, 3, 6, 9, 12, 15, 18, 22, 26, and 30 days. Five milliliters of fresh PBS solution was then added to each tube. For method 2, which mimicked an in vivo environment with no fluid exchange, each of 51 tubes (ie, 3 tubes/17 sample collection times) contained 3 CI-CSH beads and 5 mL of PBS solution. Eluent samples were obtained from the assigned tubes for each time point. All samples were analyzed for platinum content by inductively coupled plasma–mass spectrometry.
RESULTS Platinum was released from CI-CSH beads for 22 to 30 days. Significant differences were found in platinum concentration and percentage of platinum eluted from CI-CSH beads over time for each method. Platinum concentrations and elution percentages in method 2 samples were significantly higher than those of method 1 samples, except for the first hour measurements.
CONCLUSIONS AND CLINICAL RELEVANCE Sample collection methods 1 and 2 may provide estimates of the minimum and maximum platinum release, respectively, from CI-CSH beads in vivo.
OBJECTIVE To characterize the elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate (CSH) beads in vitro.
SAMPLE 60 carboplatin-impregnated CSH beads and 9 CSH beads without added carboplatin (controls).
PROCEDURES Carboplatin-impregnated CSH beads (each containing 4.6 mg of carboplatin [2.4 mg of platinum]) were placed into separate 10-mL plastic tubes containing 5 mL of PBSS in groups of 1, 3, 6, or 10; 3 control beads were placed into a single tube of PBSS at the same volume. Experiments were conducted in triplicate at 37°C and a pH of 7.4 with constant agitation. Eluent samples were collected at 1, 2, 3, 6, 12, 24, and 72 hours. Samples were analyzed for platinum content by inductively coupled plasma–mass spectrometry.
RESULTS The mean concentration of platinum released per carboplatin-impregnated bead over 72 hours was 445.3 mg/L. Cumulative concentrations of platinum eluted increased as the number of beads per tube increased. There was a significant difference in platinum concentrations over time, with values increasing over the first 12 hours and then declining for all tubes. There was also a significant difference in percentage of total incorporated platinum released into tubes with different numbers of beads: the percentage of eluted platinum was higher in tubes containing 1 or 3 beads than in those containing 6 or 10 beads.
CONCLUSIONS AND CLINICAL RELEVANCE Carboplatin-impregnated CSH beads eluted platinum over 72 hours. Further studies are needed to determine whether implantation of carboplatin-impregnated CSH beads results in detectable levels of platinum systemically and whether the platinum concentrations eluted locally are toxic to tumor cells.
Objective—To describe clinical outcome of dogs with mast cell tumors (MCTs) arising from the oral mucosa, oral mucocutaneous junction, or perioral region of the muzzle and evaluate the potential role of the chemokine receptor type 7 (CCR7) in the biological behavior of these tumors.
Design—Retrospective case series.
Animals—44 dogs with MCTs of the oral mucosa (n = 14), oral mucocutaneous junction (19), or perioral region of the muzzle (11).
Procedures—Medical records were reviewed for information on signalment, regional metastasis, treatments, cause of death, and survival time. Twenty of the 44 cases had stored histologic samples available for immunohistochemical staining for CCR7
Results—For all dogs, median survival time was 52 months. Twenty-six (59%) dogs had regional lymph node metastasis on admission. Median survival time for dogs with lymph node metastasis was 14 months, whereas median survival time was not reached for dogs without lymph node metastasis. Intensity of staining for CCR7 was not significantly associated with the presence of regional lymph node metastasis or survival time.
Conclusions and Clinical Relevance—Results suggested that in dogs with MCTs arising from the oral mucosa, oral mucocutaneous junction, or perioral region of the muzzle, the presence of regional lymph node metastasis at the time of diagnosis was a negative prognostic factor. However, prolonged survival times could be achieved with treatment. In addition, CCR7 expression in the primary tumor was not significantly associated with the presence of regional lymph node metastasis or survival time.
Objective—To evaluate factors associated with second remission in dogs with lymphoma retreated with a cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) protocol after relapse following initial treatment with a first-line 6-month CHOP protocol.
Design—Retrospective case series.
Animals—95 dogs with lymphoma.
Procedures—Medical records were reviewed. Remission duration was estimated by use of the Kaplan-Meier method. Factors potentially associated with prognosis were examined.
Results—Median remission duration after the first-line CHOP protocol was 289 days (range, 150 to 1,457 days). Overall, 78% (95% confidence interval [CI], 69% to 86%) of dogs achieved a complete remission following retreatment, with a median second remission duration of 159 days (95% CI, 126 to 212 days). Duration of time off chemotherapy was associated with likelihood of response to retreatment; median time off chemotherapy was 140 days for dogs that achieved a complete remission after retreatment and 84 days for dogs that failed to respond to retreatment. Second remission duration was associated with remission duration after initial chemotherapy; median second remission duration for dogs with initial remission duration ≥ 289 days was 214 days (95% CI, 168 to 491 days), compared with 98 days (95% CI, 70 to 144 days) for dogs with initial remission duration < 289 days.
Conclusions and Clinical Relevance—Findings suggested that retreatment with the CHOP protocol can be effective in dogs with lymphoma that successfully complete an initial 6-month CHOP protocol.
Objective—To evaluate the veterinary version of the
bladder tumor antigen (V-BTA) test as a screening test
for transitional cell carcinoma (TCC) of the lower urinary
tract of dogs.
Animals—229 client-owned dogs.
Procedure—Urine samples from dogs were shipped
overnight to a single laboratory to facilitate testing
within 48 hours of collection by use of the V-BTA rapid
latex agglutination urine dipstick test. Groups of dogs
included the following: 1) dogs with TCC of the lower
urinary tract, 2) healthy control dogs, 3) unhealthy
control dogs with non-TCC urinary tract disease, and
4) unhealthy control dogs without urinary tract disease.
Test sensitivity and specificity were calculated
by use of standard methods. Logistic models were
developed to assess the effect of disease status, test
conditions, urine composition, and signalment on the
performance of the V-BTA test.
Results—A total of 229 urine samples were analyzed,
including 48 from dogs with suspected (n = 3) or confirmed
(45) TCC. Test sensitivities were 88, 87, and
85% for all dogs with (suspected and confirmed) TCC,
dogs with confirmed TCC at any site, and dogs with
confirmed TCC of the urinary bladder, respectively.
Test specificities were 84, 41, and 86% for healthy
control dogs, unhealthy control dogs with non-TCC
urinary tract disease, and unhealthy control dogs
without urinary tract disease, respectively. The test
performed slightly better on centrifuged urine samples
than on uncentrifuged urine samples.
Conclusions and Clinical Relevance—Our results
indicate that the V-BTA test is useful in screening for
urinary tract TCC in dogs. (Am J Vet Res