To evaluate adverse events and outcomes in dogs with appendicular osteosarcoma treated with limb amputation followed by a single SC infusion of carboplatin.
45 client-owned dogs with appendicular osteosarcoma treated with limb amputation and SC infusion of carboplatin between January 1, 2006, and January 15, 2017.
Medical records were reviewed, and data collected included signalment, tumor location, treatment, results of clinicopathologic analyses and diagnostic imaging, adverse effects of chemotherapy, metastasis-free interval, survival time, and communications with owners and referring veterinarians. Findings were evaluated with the Kaplan-Meier survival analysis and Mantel-Haenszel log-rank test.
45 dogs were identified that met the inclusion criteria (12 of the 45 dogs had been reported in a previous case series). No dogs had pulmonary metastases detectable by CT or radiography before treatment. All dogs completed the protocol as planned. Median survival time (MST) was 196 days; metastasis-free interval was 197 days. Three of the 45 (7%) dogs required hospitalization for gastrointestinal signs related to chemotherapy. There were no chemotherapy-related deaths.
CONCLUSIONS AND CLINICAL RELEVANCE
Results indicated that although treatment with SC infusion of carboplatin was well tolerated, the MST for dogs in the present study was similar to reported MSTs in dogs with appendicular osteosarcoma treated with limb amputation alone and was in the lower range of historically reported survival times for dogs receiving IV adjunctive chemotherapy. Therefore, we could not recommend this protocol of SC infusion of carboplatin but recommended that protocols with IV administration of carboplatin be used instead.
An 8-year-old spayed female Shih Tzu crossbreed dog (dog 1) and a 13-year-old neutered male Miniature Fox Terrier (dog 2) were evaluated for removal of neoplasms involving both the frontal lobe and olfactory bulb.
Physical examination revealed decreased menace response and behavioral changes in both dogs. For dog 1, neuroanatomic localization of the lesion was the left forebrain region; for dog 2, neuroanatomic localization of the lesion was the right forebrain region. Both dogs underwent CT, and dog 1 also underwent MRI. Results of diagnostic imaging were consistent with frontal lobe and olfactory bulb neoplasia in both cases. Dog 1 had lysis of the frontal bone adjacent to the neoplasm.
TREATMENT AND OUTCOME
Both dogs underwent a transorbital craniectomy to permit surgical tumor removal. Dog 1 was discharged from the hospital 48 hours after surgery, at which time its mentation and cranial nerve examination findings were considered normal. Dog 2 developed neurologic deterioration after surgery but was ultimately discharged from the hospital after 72 hours, at which time its mentation appeared normal.
The transorbital approach to the cranium provided excellent access to facilitate removal of frontal lobe and olfactory bulb neoplasms in these 2 dogs.
To investigate putative associations between oral melanoma size and variables of histologic grade such as mitotic index, nuclear atypia, junctional activity, ulceration, lymphatic invasion, and degree of pigmentation.
59 samples of oral melanomas from dogs sourced from 6 diagnostic laboratories within Australia.
The size of each melanoma was microscopically measured, and each sample was evaluated for variables of histologic grade including mitotic index, nuclear atypia, junctional activity, ulceration, lymphatic invasion, and degree of pigmentation by a veterinary pathologist. The association between tumor size and histologic outcomes was then statistically evaluated.
A significant relationship was identified between the size of oral melanomas and a single variable of histologic grade, lymphatic invasion, with larger tumors more likely to show lymphatic invasion. Further analysis revealed 2 applicable size thresholds for different clinical scenarios. Results indicated lymphatic invasion can confidently be ruled out for tumors < 6.5 mm in diameter (100% sensitivity) and ruled in for tumors ≥ 24.5 mm in diameter (100% specificity).
CONCLUSIONS AND CLINICAL RELEVANCE
An association was found for oral melanomas of dogs between tumor size and lymphatic invasion.
Objective—To evaluate adverse effects and survival times in dogs with osteosarcoma that received a single SC infusion of carboplatin as adjunctive chemotherapeutic treatment following limb amputation or limb-sparing surgery.
Design—Retrospective case series.
Animals—17 client-owned dogs with spontaneously occurring osteosarcoma.
Procedures—Medical records of dogs that underwent limb amputation or limb-sparing surgery followed by a single continuous SC infusion of carboplatin (total dose, 300 mg/m2 infused over 3, 5, or 7 days) were evaluated. Signalment, tumor location, type of surgery (amputation or limb-sparing), duration of carboplatin infusion, results of hematologic and serum biochemical analyses, and adverse effects were recorded. Kaplan-Meier survival analysis was performed.
Results—Median survival time for all dogs was 365 days. Nine dogs had adverse bone marrow–related (hematologic) effects, 1 had adverse gastrointestinal effects, and 7 had infections at the surgical site. No significant differences were detected in survival times of dogs grouped according to tumor location, type of surgery, duration of carboplatin infusion, or development of postoperative infection.
Conclusions and Clinical Relevance—Median survival time and adverse effects in dogs with osteosarcoma that received a single SC infusion of carboplatin over a 3-, 5-, or 7-day period as adjunctive treatment following limb amputation or limb-sparing surgery were comparable to those of previously reported chemotherapy protocols requiring IV drug administration over several weeks. Further investigation is needed to evaluate the efficacy of this protocol as adjunctive treatment for osteosarcoma and other tumors in dogs.
Objective—To determine outcomes for dogs with soft tissue sarcomas in the distal aspects of the limbs that underwent second intention healing after wide excision (2-cm lateral surgical margins and a margin 1 fascial plane deep) of the tumors.
Design—Retrospective case series.
Animals—31 dogs with soft tissue sarcomas in the distal aspects of the limbs that underwent second intention healing following wide local excision of their tumors.
Procedures—Tumors were excised with 2-cm lateral margins and a margin 1 fascial plane deep to tumors. Wounds healed by means of second intention. Time to healing, complications during healing, and information regarding tumor recurrence were recorded.
Results—All tumors were excised with histologically tumor-free margins. Twenty-nine (93.5%) wounds healed completely by second intention (median time, 53 days). Two (6.5%) dogs required free skin graft procedures to facilitate healing. Complications during open wound management developed for 7 (22.6%) dogs. Long-term complications were detected for 8 (25.8%) dogs, including intermittent epidermal disruption (5/31 [16.1%]) and wound contracture (3/31 [9.7%]). All complications were managed conservatively. Local tumor recurrence was detected for 1 (3.2%) dog. Median follow-up time was 980 days (range, 380 to 2,356 days). No patients died because of tumor-related causes.
Conclusions and Clinical Relevance—Results of this study indicated second intention healing of large wounds in the distal aspects of the limbs was complete and typically without complications for dogs that underwent wide excision of soft tissue sarcomas. Wide local excision of soft tissue sarcomas in the distal aspects of the limbs with 2-cm lateral margins and margins 1 fascial plane deep to the tumors provided excellent long-term local tumor control.
Objective—To evaluate outcomes of radical excision of feline injection-site sarcomas (ISS) via assessment of local recurrence and metastasis rates, survival times, and complications associated with surgery.
Design—Retrospective case series.
Animals—91 cats with ISS.
Procedures—Medical records of cats that had radical excision of ISS without adjunctive treatment were reviewed. Information extracted included sex, type of surgical procedure, histologic tumor grade, tumor diameter, time from tumor detection to definitive surgery, complications associated with surgery, whether tumors recurred locally or metastasized, and survival times. Diagnosis of ISS was histologically confirmed, and additional follow-up was performed.
Results—Overall median survival time was 901 days. Thirteen of 91 (14%) cats had local tumor recurrence; 18 (20%) cats had evidence of metastasis after surgery. Median survival time of cats with and without recurrence was 499 and 1,461 days, respectively. Median survival time of cats with and without metastasis was 388 and 1,528 days, respectively. Tumor recurrence and metastasis were significantly associated with survival time, whereas other examined variables were not. Major complications occurred in 10 cats, including 7 with incisional dehiscence.
Conclusions and Clinical Relevance—Radical excision of ISS resulted in a metastasis rate similar to rates reported previously; the local recurrence rate appeared to be substantially less than rates reported after less aggressive surgeries, with or without adjuvant treatment. Major complication rates were similar to rates reported previously after aggressive surgical resection of ISS. Radical excision may be a valuable means of attaining an improved outcome in the treatment of feline ISS.
OBJECTIVE To describe the signalment, clinical signs, biological behavior, and outcome for cats with apocrine gland anal sac adenocarcinoma (AGASACA) that underwent surgical excision.
DESIGN Retrospective case series.
ANIMALS 30 client-owned cats.
PROCEDURES Databases of 13 Veterinary Society of Surgical Oncology member–affiliated institutions were searched for records of cats with a histologic diagnosis of AGASACA that underwent tumor excision. For each cat, information regarding signalment, clinical signs, diagnostic test results, treatment, and outcome was extracted from the medical record. The Kaplan-Meier method was used to determine median time to local recurrence (TLR), disease-free interval (DFI), and survival time. Cox regression was used to identify factors associated with TLR, DFI, and survival time.
RESULTS Perineal ulceration or discharge was the most common clinical sign in affected cats. Eleven cats developed local recurrence at a median of 96 days after AGASACA excision. Incomplete tumor margins and a high nuclear pleomorphic score were risk factors for local recurrence. Nuclear pleomorphic score was negatively associated with DFI. Local recurrence and a high nuclear pleomorphic score were risk factors for death. Median DFI and survival time were 234 and 260 days, respectively.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that, in cats, perineal ulceration or discharge should raise suspicion of AGASACA and prompt rectal and anal sac examinations. Local recurrence was the most common life-limiting event in cats that underwent surgery for treatment of AGASACA, suggesting that wide margins should be obtained whenever possible during AGASACA excision. Efficacy of chemotherapy and radiation therapy for treatment of cats with AGASACA requires further investigation. (J Am Vet Med Assoc 2019;254:716–722)