Julius M. Liptak

Primary Renal Neoplasia of Dogs

BACKGROUNDnPrimary renal tumors are diagnosed uncommonly in dogs.nnnHYPOTHESISnSigns and survival will differ among different categories of primary renal tumors.nnnANIMALSnData were collected from the medical records of 82 dogs with primary renal tumors diagnosed by examination of tissue obtained by ultrasound-guided biopsy, needle aspiration, surgery, or at postmortem examination.nnnMETHODSnThis was a multi-institutional, retrospective study.nnnRESULTSnForty-nine dogs had carcinomas, 28 had sarcomas, and 5 had nephroblastomas. The dogs were geriatric (mean 8.1 years; range: 1-17) with a weight of 24.9 kg (range: 4.5-80). Tumors occurred with equal frequency in each kidney with 4% occurring bilaterally. Initial signs included one or more of hematuria, inappetance, lethargy. weight loss, or a palpable abdominal mass. Pain was reported more frequently in dogs with sarcomas (5/28). The most common hematologic abnormalities were neutrophilia (22/63), anemia (21/64), and thrombocytopenia (6/68). Polycythemia was present in 3 dogs and resolved with treatment. Hematuria (28/49), pyuria (26/49), proteinuria (24/50), and isosthenuria (20/56) were the most frequently observed abnormalities on urinalysis. Pulmonary metastases were noted on thoracic radiographs in 16% of dogs at diagnosis. Seventy-seven percent of dogs had metastatic disease at the time of death. Median survival for dogs with carcinomas was 16 months (range 0-59 months), for dogs with sarcomas 9 months (range 0-70 months), and for dogs with nephroblastomas 6 months (range 0-6 months).nnnCONCLUSIONS AND CLINICAL IMPORTANCEnPrimary renal tumors in dogs are generally highly malignant with surgery being the only treatment that improves survival.

Biodegradable Cisplatin Polymer in Limb-Sparing Surgery for Canine Osteosarcoma

Background: The rate of local recurrence of osteosarcoma after limb-sparing surgery in dogs and humans has been reported up to 28%. The primary purpose of this study was to determine whether a biodegradable cisplatin-containing implant (OPLA-Pt), inserted into the limb-sparing surgery site at the time of surgery, would decrease the rate of local recurrence. Secondary aims included evaluation of systemic toxicity associated with the release of cisplatin from the implant and identification of prognostic factors associated with limb-sparing surgery for osteosarcoma in dogs.Methods: Eighty dogs with spontaneously occurring osteosarcoma were treated with limb-sparing surgery. They were randomized to receive the biodegradable implant either without cisplatin (control group) or with cisplatin (OPLA-Pt group) and were targeted to receive four doses of an adjuvant cisplatin chemotherapy protocol.Results: Although this was not statistically significant (P = .071), dogs in the OPLA-Pt group were 53.5% less likely to develop local recurrence than dogs in the control group. There were no significant differences in systemic toxicity between treatment arms. Incomplete surgical resection, absence of infection, and fewer than four doses of adjuvant chemotherapy had a significant correlation with local recurrence and survival according to univariate analyses, although only incomplete surgical resection remained significant for local recurrence after multivariate analysis.Conclusions: Local tumor recurrence may be decreased after limb-sparing surgery by use of biodegradable implants impregnated with chemotherapeutic agents.

Radiation therapy for canine appendicular osteosarcoma.

Radiation therapy (RT) for the management of canine appendicular osteosarcoma (OSA) can be described as either palliative- or curative intent. Palliative RT uses coarsely fractionated external beam RT or radiopharmaceuticals to provide relief of pain and lameness associated with OSA while resulting in minimal, if any, radiation-induced acute adverse effects. Limb amputation and chemotherapy are considered (together) the standard of care for curative-intent treatment of canine appendicular OSA. When limb amputation is not possible, RT can be used for limb sparing and is supplemented with chemotherapy for presumed micrometastatic disease. Fractionated tumour irradiation with curative intent appears to be ineffective and local disease control can more likely be achieved when stereotactic radiosurgery or intra-operative extracorporeal irradiation is combined with strict case selection and adjunctive chemotherapy. The availability of limb-sparing RT is limited by experience and availability of specialised equipment. When planned and administered appropriately, radiation-associated adverse effects are often mild and self-limiting.

Biologic Behavior and Clinical Outcome of 25 Dogs with Canine Appendicular Chondrosarcoma Treated by Amputation: A Veterinary Society of Surgical Oncology Retrospective Study

OBJECTIVEnTo characterize biologic behavior, clinical outcome, and effect of histologic grade on prognosis for dogs with appendicular chondrosarcoma treated by amputation alone.nnnSTUDY DESIGNnCase series.nnnANIMALSnDogs (n=25) with appendicular chondrosarcoma.nnnMETHODSnMedical records were searched to identify dogs with appendicular chondrosarcoma treated by limb amputation alone. Information recorded included signalment, anatomic location, radiographic appearance, and development of metastasis. Histopathologic diagnosis was confirmed and graded (1, 2, or 3). Survival curves were generated by the Kaplan-Meier method and the association between covariates (gender, age, weight, and tumor grade) and survival were evaluated using the univariate proportional hazards model.nnnRESULTSnHistopathology slides were available for 25 dogs. Rates of pulmonary metastasis were as follows: grade 1-0%, grade 2-31%, and grade 3-50%. Overall median survival time (MST) was 979 days. Age, weight, and sex were not significantly associated with survival (P=.16; .33; and .31, respectively). Survival was significantly associated with tumor grade (P=.008), with dogs with tumor grade of 1, 2, and 3 having MSTs of 6, 2.7, and 0.9 years, respectively.nnnCONCLUSIONnCanine appendicular chondrosarcoma can be treated effectively with amputation alone. Low to intermediate grade chondrosarcoma has a good prognosis, whereas high-grade tumors appear to behave aggressively.nnnCLINICAL RELEVANCEnThe overall prognosis for appendicular chondrosarcoma is better than that of appendicular osteosarcoma treated by amputation alone or in combination with chemotherapy.

Cranial mediastinal carcinomas in nine dogs

Nine dogs were diagnosed with cranial mediastinal carcinomas. Based on histological and immunohistochemical analysis, four dogs were diagnosed with ectopic follicular cell thyroid carcinomas, one dog with ectopic medullary cell thyroid carcinoma, two dogs with neuroendocrine carcinomas and two dogs with anaplastic carcinomas. Clinical signs and physical examination findings were associated with a space-occupying mass, although one dog was diagnosed with functional hyperthyroidism. Surgical resection was attempted in eight dogs. The cranial mediastinal mass was invasive either into the heart or into the cranial vena cava in three dogs. Resection was complete in six dogs and unresectable in two dogs. All dogs survived surgery, but four dogs developed pulmonary thromboembolism and two dogs died of respiratory complications postoperatively. Adjunctive therapies included pre-operative radiation therapy (n=1) and postoperative chemotherapy (n=3). Three dogs had metastasis at the time of diagnosis, but none developed metastasis following surgery. The overall median survival time was 243 days. Local invasion, pleural effusion and metastasis did not have a negative impact on survival time in this small case series.

Reconstruction of Chest Wall Defects After Rib Tumor Resection: A Comparison of Autogenous, Prosthetic, and Composite Techniques in 44 Dogs

OBJECTIVEnTo compare short- and long-term outcome and complications of chest wall reconstruction in dogs using autogenous, prosthetic, and composite autogenous-prosthetic techniques.nnnSTUDY DESIGNnHistorical cohort.nnnANIMALSnDogs (n=44) with spontaneous tumors arising from or involving the chest wall.nnnMETHODSnMedical records were reviewed for dogs with rib and/or sternal tumors treated by chest wall resection and reconstruction. Signalment, preoperative clinical features, intraoperative findings and complications, reconstruction technique (autogenous muscle flap, prosthetic mesh, or composite autogenous-prosthetic technique), and short- (< or =14 days) and long-term (>14 days) postoperative complications were determined from the medical records and telephone contact with owners and referring veterinarians. Associations between chest wall reconstruction technique and postoperative complications were tested with Cox proportional hazards.nnnRESULTSnChest wall defects were reconstructed with autogenous muscle flaps (29 dogs), prosthetic mesh (3), and a composite technique of prosthetic mesh and either autogenous muscle or omental pedicle flap (12). Early postoperative complications were recorded in 8 dogs (18.2%) and included seroma (5) and pleural effusion and peripheral edema (3). One dog had a late complication (2.3%) with a mesh-related infection 767 days postoperatively. Overall, complications occurred in 10.3% of autogenous, 25.0% of composite, and 66.7% of prosthetic reconstructions. Chest wall reconstruction with Marlex mesh alone was associated with a significantly increased risk of postoperative complications compared with autogenous reconstruction (P=.027). Reconstruction of sternal defects (3), 2 of which were performed with Marlex mesh alone, was associated with a significantly increased risk of complications compared with lateral chest wall reconstructions (P=.037).nnnCONCLUSIONSnLarge chest wall defects can be reconstructed with autogenous and composite techniques, but prosthetic mesh should be covered with well-vascularized autogenous muscle or omentum to decrease the risk of postoperative complications. Sternal defects should be reconstructed with rigid techniques.nnnCLINICAL RELEVANCEnChest wall reconstruction with autogenous muscle flaps or a combination of autogenous techniques with prosthetic mesh is associated with a low rate of infection and other complications.

Efficacy of systemic adjuvant therapies administered to dogs after excision of oral malignant melanomas: 151 cases (2001-2012)

OBJECTIVEnTo determine prognostic factors for and compare outcome among dogs with oral malignant melanoma following excision with or without various systemic adjuvant therapies.nnnDESIGNnRetrospective case series.nnnANIMALSn151 dogs with naturally occurring oral malignant melanomas treated by excision with or without adjuvant therapies from 2001 to 2012.nnnPROCEDURESnCase accrual was solicited from Veterinary Society of Surgical Oncology members via an email list service. Information collected from case records included signalment, tumor staging, tumor characteristics, type of surgical excision, histologic diagnosis, adjuvant therapy, and survival time.nnnRESULTSnThe overall median survival time was 346 days. Results of multivariate analysis indicated that tumor size, patient age, and intralesional excision (vs marginal, wide, or radical excision) were considered poor prognostic indicators. All other demographic and clinical variables were not significantly associated with survival time after adjusting for the aforementioned 3 variables. A clear survival benefit was not evident with any systemic adjuvant therapy, including vaccination against melanoma or chemotherapy; however, the number of dogs in each treatment group was small. Ninety-eight dogs received no postoperative adjuvant therapy, and there was no difference in survival time between dogs that did (335 days) and did not (352 days) receive systemic adjuvant therapy.nnnCONCLUSIONS AND CLINICAL RELEVANCEnFor dogs with oral malignant melanoma, increasing tumor size and age were negative prognostic factors. Complete excision of all macroscopic tumor burden improved survival time. Long-term survival was possible following surgery alone. Although systemic adjuvant therapy was not found to improve survival time, this could have been due to type II error.

Oncologic Outcome after Curative-Intent Treatment in 39 Dogs with Primary Chest Wall Tumors (1992–2005)

OBJECTIVEnTo describe the clinical features and determine oncologic outcome and prognostic factors for dogs with primary tumors of the osseous chest wall.nnnSTUDY DESIGNnHistorical cohort.nnnANIMALSnDogs (n=39) with spontaneous tumors involving the chest wall.nnnMETHODSnMedical records were reviewed for dogs with rib and/or sternal tumors treated by chest wall resection and reconstruction. Signalment, preoperative clinical features, reconstruction technique, and oncologic outcome (local tumor recurrence, metastasis, and survival time) were determined from medical records and by telephone contact with owners and referring veterinarians. Oncologic outcome and prognostic factors were determined using Kaplan-Meier survival analysis and Cox proportional hazards. Logistic regression was used to determine if increased serum alkaline phosphatase (ALP) concentration was associated with tumor type.nnnRESULTSnOf the 39 dogs with tumors arising from the chest wall, 25 had osteosarcoma, 12 had chondrosarcoma, and 2 dogs had hemangiosarcoma. Median survival time (MST) for dogs with rib osteosarcoma was 290 days. Increased activity of total ALP significantly decreased survival in dogs with osteosarcoma (210 days versus 675 days, P=.0035). MST for dogs with rib chondrosarcoma was not reached (mean 1301 days) and survival was significantly greater than all other types of rib tumors (P=.0321).nnnCONCLUSIONnRib tumors should be resected with wide margins to decrease the risk of incomplete excision, because local tumor recurrence has a significant impact on the survival time. The prognosis for dogs with rib chondrosarcoma is very good, but guarded for other types of tumors.nnnCLINICAL RELEVANCEnOsteosarcoma and chondrosarcoma are the most common primary tumors of the chest wall. Prognosis for dogs with primary rib chondrosarcoma is very good with surgery alone, but surgery and adjunctive chemotherapy is recommended for dogs with primary rib osteosarcoma and the prognosis remains guarded.

Pulmonary metastatectomy in the management of four dogs with hypertrophic osteopathy

The efficacy and outcome of pulmonary metastatectomy in the management of hypertrophic osteopathy (HO) secondary to metastatic osteosarcoma was retrospectively evaluated in four dogs. Metastatectomy was performed by subpleural enucleation, partial lung lobectomy or complete lung lobectomy through either a median sternotomy or thoracoscopically. Perioperative morbidity was minimal. Clinical signs associated with HO resolved within 24 h of pulmonary metastatectomy in all dogs. Durable remission of symptomatic HO was achieved in all dogs (range, 50-294 days), although recurrence of HO was noted in one dog, 246 days post metastatectomy due to metastasis to the lungs and chest wall. Pulmonary metastatectomy resulted in a rapid and prolonged resolution of HO, and the clinical benefits of metastatectomy potentially exceed the morbidity associated with the surgical procedure.

Outcome after Repair of a Sarcoma-Related Pathologic Fracture in Dogs: A Veterinary Society of Surgical Oncology Retrospective Study

OBJECTIVEnTo report outcome in dogs after internal fixation of a sarcoma-related pathologic fracture of the appendicular skeleton.nnnSTUDY DESIGNnMulti-institutional case series.nnnANIMALSnDogs (n=16).nnnMETHODSnMedical records of participating VSSO members were reviewed for dogs with pathologic fracture associated with a confirmed bone sarcoma of the appendicular skeleton repaired by external or internal fixation. Dogs were included if they had a histological diagnosis of osteosarcoma or sarcoma and excluded if they had radiation before fracture. Data collected were analyzed for signalment, fracture location, staging performed, method of fracture fixation, histopathology, adjunctive treatment and outcome.nnnRESULTSnSignalment and fracture location of 16 dogs that met the inclusion criteria was similar to dogs with appendicular OSA without fracture. One of 14 dogs had pulmonary metastasis and 3 of 5 dogs had bone metastasis. Bone plate or interlocking nail were used for repair in 12 dogs. Limb use immediately after surgery in 13 dogs was good (4), weight-bearing but lame (7) and non-weight bearing (2). Adjunctive therapy was administered in 5 dogs (chemotherapy, 3; radiation, 4; pamidronate, 3). Survival time ranged from 18 to 897 days; median survival was 166 days.nnnCONCLUSIONSnRepair of pathologic fracture can result in palliation and prolonged survival.