OBJECTIVE To determine survival time and metastatic rate for dogs with early-stage anal sac adenocarcinoma (ASACA) treated with surgery alone and assess whether specific clinical, pathological, or immunohistochemical factors were predictive of outcome for those dogs.
DESIGN Retrospective case series.
ANIMALS 34 dogs with early-stage, nonmetastatic ASACA that were treated with surgery only.
PROCEDURES Medical record databases of 2 referral hospitals were searched to identify dogs examined between 2002 and 2013 that had a diagnosis of nonmetastatic ASACA that was < 3.2 cm at its largest diameter. Only dogs that received surgical treatment alone were included in the study. For each dog, information extracted from the medical record included signalment, clinical and diagnostic test findings, tumor characteristics, and outcome. When available, archived tumor specimens were histologically reviewed and tumor characteristics were described; Ki-67 and E-cadherin expressions were evaluated by use of immunohistochemical methods. Clinical, pathological, and immunohistochemical factors were assessed for associations with survival time and tumor recurrence and metastasis rates.
RESULTS Median survival time was 1,237 days. Seven dogs had tumor recurrence and 9 dogs developed metastatic disease at a median of 354 and 589 days, respectively, after primary tumor removal. Cellular pleomorphism was positively associated with development of metastatic disease. No other factors evaluated were associated with outcome.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated dogs with early-stage nonmetastatic ASACA generally had a favorable outcome following surgical removal of the primary tumor alone. Routine rectal examination may be a simple and useful method for detection of dogs with early-stage ASACA.
CASE DESCRIPTION 4 dogs with a slow-growing mass in the cervical region were evaluated.
CLINICAL FINDINGS All dogs had no clinical signs at the time of the evaluation. There was no apparent evidence of visceral metastases or other primary tumor based on available CT or MRI data for any dog.
TREATMENT AND OUTCOME For each dog, surgery to remove the mass was performed. Histologic examination of the excised tissue revealed a completely excised grade 1 or 2 lymph node hemangiosarcoma. All dogs received adjuvant chemotherapy; 2 dogs underwent curative intent chemotherapy, 1 dog underwent metronomic treatment with cyclophosphamide, and 1 dog underwent metronomic treatment with chlorambucil. The survival time was 259 days in 1 dog; 3 dogs were still alive 615, 399, and 365 days after surgery.
CLINICAL RELEVANCE Primary nodal hemangiosarcoma in dogs is a rare and, to the authors' knowledge, previously undescribed disease that appears to develop in the cervical lymph nodes as a slow-growing mass or masses. Surgical excision and adjunct treatment resulted in long survival times for 3 of the 4 dogs of the present report. Given the aggressive biologic behavior of hemangiosarcomas in other body locations, adjunct chemotherapy should be considered for affected dogs, although its role in the cases described in this report was unclear. Additional clinical information is required to further characterize the biologic behavior of this tumor type and determine the expected survival times and associated risk factors in dogs.
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 examine the biological behavior of ulnar osteosarcoma and evaluate predictors of survival time in dogs.
Design—Retrospective case series.
Animals—30 dogs with primary ulnar osteosarcoma.
Procedures—Medical records were reviewed. Variables recorded and examined to identify predictors of survival time were signalment, tumor location in the ulna, tumor length, serum alkaline phosphatase activity, surgery type, completeness of excision, tumor stage, tumor grade, histologic subtype, development of metastases, and use of chemotherapy.
Results—30 cases were identified from 9 institutions. Eleven dogs were treated with partial ulnar ostectomy and 14 with amputation; in 5 dogs, a resection was not performed. Twenty-two dogs received chemotherapy. Median disease-free interval and survival time were 437 and 463 days, respectively. Negative prognostic factors for survival time determined via univariate analyses were histologic subtype and development of lung metastases. Telangiectatic or telangiectatic-mixed subtype (n = 5) was the only negative prognostic factor identified via multivariate analysis (median survival time, 208 days). Dogs with telangiectatic subtype were 6.99 times as likely to die of the disease.
Conclusions and Clinical Relevance—The prognosis for ulnar osteosarcoma in this population was no worse and may have been better than the prognosis for dogs with osteosarcoma involving other appendicular sites. Partial ulnar ostectomy was associated with a low complication rate and good to excellent function and did not compromise survival time. Telangiectatic or telangiectatic-mixed histologic subtype was a negative prognostic factor for survival time. The efficacy of chemotherapy requires further evaluation.