Objective—To identify variables associated with prognosis in dogs undergoing surgical excision of anal sac apocrine gland adenocarcinomas (ASACs) with and without adjunctive chemotherapy.
Design—Retrospective case series.
Animals—42 dogs with ASACs.
Procedures—Information on signalment, clinical signs, diagnostic procedures, surgical procedures, adjunctive therapies, survival time, and disease-free interval was obtained from the medical records.
Results—Survival time was significantly associated with the presence of sublumbar lymphadenopathy and sublumbar lymph node extirpation, with median survival time significantly shorter for dogs with sublumbar lymphadenopathy (hazard ratio, 2.31) than for those without and for dogs that underwent lymph node extirpation (hazard ratio, 2.31) than for those that did not. Disease-free interval was significantly associated with the presence of sublumbar lymphadenopathy, lymph node extirpation, and administration of platinum-containing chemotherapeutic agents, with median disease-free interval significantly shorter for dogs with sublumbar lymphadenopathy (hazard ratio, 2.47) than for those without, for dogs that underwent lymph node extirpation (hazard ratio, 2.47) than for those that did not, and for dogs that received platinum-containing chemotherapeutic agents (hazard ratio, 2.69) than for those that did not. Survival time and disease-free interval did not differ among groups when dogs were grouped on the basis of histopathologic margins (complete vs marginal vs incomplete excision).
Conclusions and Clinical Relevance—Results suggested that in dogs with ASAC undergoing surgical excision, the presence of sublumbar lymphadenopathy and lymph node extirpation were both negative prognostic factors. However, completeness of surgical excision was not associated with survival time or disease-free interval.
Objective—To evaluate response rate and duration of
malignant melanomas in dogs treated with carboplatin.
Animals—27 client-owned dogs with spontaneously
occurring measurable malignant melanomas.
Procedure—Records of dogs with melanomas treated
with carboplatin from October 1989 to June 2000
were reviewed. Carboplatin was administered IV at
doses of 300 or 350 mg/m2 of body surface area.
Response to treatment and evidence of drug toxicity
Result—Response to treatment could be evaluated in
25 dogs. Of those, overall response rate was 28%.
One dog had a complete response, 6 (24%) dogs had
a partial response (> 50% reduction in tumor burden).
Median duration of partial response was 165 days.
Eighteen dogs had stable disease (n = 9; 36%) or progressive
disease (9; 36%). Response to treatment
was significantly associated with carboplatin dose on
a milligram per kilogram basis (15.1 mg/kg [6.9 mg/lb]
of body weight vs 12.6 mg/kg [5.7 mg/lb]). Evidence
of gastrointestinal toxicosis could be assessed in 27
dogs. Mean body weight of 5 dogs that developed
gastrointestinal toxicosis was significantly less than
that of 22 dogs without gastrointestinal toxicosis (9.9
kg [21.8 lb] vs 19.3 kg [42.5 lb]).
Conclusions and Clinical Relevance—Carboplatin
had activity against macroscopic spontaneously
occurring malignant melanomas in dogs and should
be considered as an adjunctive treatment for microscopic
local or metastatic tumors. Gastrointestinal
toxicosis was associated with body weight. Because
small dogs are more likely to have adverse gastrointestinal
effects, gastrointestinal protectants should be
considered for these patients. (J Am Vet Med Assoc
Objective—To characterize the signalment, clinical
signs, biological behavior, and response to treatment
of carcinoma of the apocrine glands of the anal sac in
Animals—113 dogs with histologically confirmed carcinoma
of the apocrine glands of the anal sac.
Procedure—Data on signalment, clinical signs, and
staging were reviewed and analyzed along with treatment
modality for potential association with survival
Results—Sex distribution was approximately equal
(54% female, 46% male). One hundred four dogs
underwent treatment consisting of surgery, radiation
therapy, chemotherapy, or multimodal treatment.
Median survival for treated dogs was 544 days (range,
0 to 1,873 days). Dogs treated with chemotherapy
alone had significantly shorter survival (median, 212
days) than those receiving other treatments (median,
584 days). Dogs not treated with surgery had significantly
shorter survival (median, 402 days) than those
that underwent surgery as part of their treatment
(median, 548 days). Dogs with tumors ≥ 10 cm2 had
significantly shorter survival (median, 292 days) than
dogs with tumors ≥ 10 cm2 (median, 584 days).
Hypercalcemia was identified in 27% (n = 29) of dogs,
and those dogs had significantly shorter survival (median,
256 days), compared with those that were normocalcemic
(median, 584 days). Dogs with pulmonary
metastasis had significantly shorter survival (median,
219 days) than dogs without evidence of pulmonary
metastasis (median, 548 days).
Conclusions and Clinical Relevance—Unlike most
previous reports, this study revealed an approximately
equal sex distribution, and results suggest a more
favorable prognosis. (J Am Vet Med Assoc 2003;223: