Updates in Surgical Oncology Séguin, Bernard; Liptak, Julius M
The Veterinary clinics of North America. Small animal practice
54, Številka:
3
Journal Article
Recenzirano
New knowledge and data can influence the treatment options of dogs and cats affected by neoplasms. Partial limb amputation with the use of a prosthesis is possible in dogs. Newer studies attempt to ...define better and understand the complications and limb function associated with this approach. Limb sparing is an alternative to amputation, and three-dimensional printing allows the manufacturing of personalized endoprostheses. Finally, the recommended approach for the excision of cutaneous mast cell tumors (MCTs) is with proportional margins. In dogs, grade shifting might have occurred when removing a recurrent MCT or soft tissue sarcoma.
Soft tissue sarcomas (STSs) remain a therapeutic challenge for pediatric and adolescent and young adult (AYA) patients. Still today, surgery, radiation therapy, and chemotherapy remain the mainstay ...of treatment. Obstacles in developing new treatment approaches to improve the outcome are: few patients to enroll in clinical trials, and the diversity of tumor biology between histologic subtypes. Pet dogs may offer an additional strategy to discover and test new therapeutic avenues. The number of dogs diagnosed with a STS each year in the United States is estimated to be around 27,000 to 95,000. In comparison, approximately 900 children less than 20 years old and 1,500 AYAs between 15 and 29 years old are diagnosed with a STS each year in the United States. The mainstay for treatment of STSs in dogs is also surgery, with radiation therapy and chemotherapy when necessary. Similar to what is seen in humans, grade and stage are prognostic in dogs. In one comparative study of the histology and immunohistochemistry of canine STSs, most tumors were diagnosed as the human equivalent of undifferentiated sarcoma, spindle cell sarcoma, or unclassified spindle cell sarcoma. But much work remains to be done to fully assess the validity of canine STSs as a model. Gene expression analysis has been done in a limited number of canine STSs. Tissue banking, development of cell lines, and the ability to mobilize large-scale clinical trials will become essential in veterinary medicine to benefit both dogs and humans.
•Personalized endoprostheses and cutting guides reduce surgery time by 25–50%.•Numerical model of a limb with prosthesis is validated by biomechanical experiment.•To improve stress distribution, ...implant stiffness must be reduced to 25–50 GPa.
Osteosarcoma is the most common type of bone cancer in dogs, treatable by amputation or limb-sparing surgery. For the latter, commercially available plate – endoprosthesis assemblies require contouring, to be adapted to the patient's bone geometry, and lead to sub-optimal results. The use of additively-manufactured personalized endoprostheses and cutting guides for distal radius limb-sparing surgery in dogs presents a promising alternative.
Specialized software is used for the bone structure reconstruction from the patient's CT scans and for the design of endoprostheses and cutting guides. The prostheses are manufactured from a titanium alloy using a laser powder bed fusion system, while the cutting guides are manufactured from an ABS plastic using a fused deposition modeling system. A finite element model of an instrumented limb was developed and validated using experimental testing of a cadaveric limb implanted with a personalized endoprosthesis.
Personalized endoprostheses and cutting guides can reduce limb sparing surgery time by 25–50% and may reduce the risk of implant failure. The numerical model was validated using the kinematics and force-displacement diagrams of the implant-limb construct. The model indicated that a modulus of elasticity of an implant material ranging from 25 to 50 GPa would improve the stress distribution within the implant. The results of the current study will allow optimization of the design of the personal implants in both veterinary and human patients.
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Objective
To describe the repair of oronasal fistulas in dogs treated for maxillary cancer, with a novel sternohyoideus‐sternothyroideus muscle flap, and to report the outcome.
Animals
Client‐owned ...dogs (n = 4) with oronasal fistulas related to cancer.
Study design
Short case series.
Methods
Maxillary defects were caused by tissue destruction by the tumor and tumor response to radiation therapy in two cases and a complication of caudal maxillectomy in two cases, one of which had neoadjuvant radiation therapy. All tumors were >4 cm at the level of the maxilla. Flaps were harvested by transecting the ipsilateral sternothyroideus and sternohyoideus muscles from their origin at the manubrium and costal cartilage. The muscles were rotated around the base of the cranial thyroid artery and tunneled subcutaneously in the neck and through an incision in the caudodorsal aspect of the oral cavity. The muscle flap was sutured to the edges of the oronasal fistula.
Results
The flap reached as far rostral as the level of the first premolar without tension. All dogs had clinical signs that improved postoperatively. All dogs had partial dehiscence of the flap.
Conclusion
This flap was associated with a high rate of complications; however, all flaps were used in challenging cases. Clinical signs related to oronasal fistula were improved in all dogs in this case series.
Veterinary Surgical Oncologyprovides in-depth coverage of surgical techniques for treating cancer in small animal patients. Organized by body system, each chapter presents detailed, well-illustrated ...descriptions of surgical procedures, with additional information on diagnostic testing, aftercare, outcomes, and prognosis. Edited and authored by members of the Veterinary Society of Surgical Oncologists, Veterinary Surgical Oncology'scomprehensive coverage of surgical treatments for cancer provides an invaluable decision-making tool and is equally useful for veterinary surgeons and veterinary oncologists.The book begins with introductory chapters on the principles of surgical oncology, multimodal therapy, and interventional radiology, then presents chapters on surgical techniques in all anatomical structures, including procedures not well covered in existing literature. The first book to focus on the surgical aspects of cancer treatment, Veterinary Surgical Oncologyis an essential reference for anyone with an interest in surgical oncology.
For some cases of canine appendicular osteosarcoma (OSA), limb‐sparing treatment options are often desired, one of which is stereotactic body radiation therapy (SBRT). A major complication of SBRT is ...fracture of the irradiated bone at the site of treatment. The present study evaluated 127 appendicular OSA sites in 122 dogs treated with SBRT to identify the most common pathologic fracture locations and configurations. A total of 50 tumours experienced a pathologic fracture, and 38 had imaging sufficient to identify fracture configuration. The distal tibia was more likely to develop a fracture than other sites. Multiple types of fracture configuration (transverse, oblique, spiral and comminuted) were observed. The distal radius was significantly more likely to develop a transverse fracture than other sites. Documentation of fracture location and configuration leads to the identification of the forces contributing to fracture occurrence, since each configuration is a result of different forces acting on each affected bone. Such knowledge is imperative for the development of new approaches to diminish the occurrence of pathologic fractures.
Many oncolytic viruses that are efficacious in murine cancer models are ineffective in humans. The outcomes of oncolytic virus treatment in dogs with spontaneous tumors may better predict human ...cancer response and improve treatment options for dogs with cancer. The objectives of this study were to evaluate the safety of treatment with myxoma virus lacking the
gene (MYXVΔserp2) and determine its immunogenicity in dogs. To achieve these objectives, dogs with spontaneous soft tissue sarcomas were treated with MYXVΔserp2 intratumorally (
= 5) or post-operatively (
= 5). In dogs treated intratumorally, clinical scores were recorded and tumor biopsies and swabs (from the mouth and virus injection site) were analyzed for viral DNA at multiple time-points. In all dogs, blood, urine, and feces were frequently collected to evaluate organ function, virus distribution, and immune response. No detrimental effects of MYXVΔserp2 treatment were observed in any canine cancer patients. No clinically significant changes in complete blood profiles, serum chemistry analyses, or urinalyses were measured. Viral DNA was isolated from one tumor swab, but viral dissemination was not observed. Anti-MYXV antibodies were occasionally detected. These findings provide needed safety information to advance clinical trials using MYXVΔserp2 to treat patients with cancer.
Background
Metastasis of appendicular osteosarcoma is most common to the lungs and is generally considered a terminal event in dogs. Behavior and prognosis associated with cutaneous or subcutaneous ...metastases (CSM) is poorly defined.
Objective
Describe the population and gather prognostic information regarding appendicular osteosarcoma with CSM in dogs.
Animals
Twenty dogs with appendicular osteosarcoma and CSM.
Methods
Retrospective case series. Medical records were searched to identify dogs diagnosed with appendicular osteosarcoma that developed CSM. Demographic data, order of metastatic events, and CSM clinical features were evaluated. Kaplan‐Meier survival curves were constructed and log‐rank tests were used to compare survival between groups of dogs.
Results
In 19 dogs (95%), CSM was an incidental finding. Seventeen dogs (85%) developed pulmonary metastasis, and 1 dog (5%) developed bone metastasis. No other metastatic sites were detected before euthanasia. The median CSM‐free interval and CSM survival time were 160 days (range: 0‐542 days) and 55 days (range: 5‐336 days), respectively. The median CSM survival time was significantly longer for dogs treated with surgery and chemotherapy (94 days) or chemotherapy only (64 days) than for dogs that did not receive these treatments (11 days) (P = .002 and P = .03, respectively). No other factors were associated with survival after diagnosis of CSM.
Conclusion and Clinical Importance
The skin or subcutaneous tissue can be the first osteosarcoma metastatic site detected. After CSM diagnosis, the prognosis is grave with median survival <2 months. Although this finding could have been biased by case selection, treatment with surgery and chemotherapy may improve outcome.
Significant changes in physical and biological systems are occurring on all continents and in most oceans, with a concentration of available data in Europe and North America. Most of these changes ...are in the direction expected with warming temperature. Here we show that these changes in natural systems since at least 1970 are occurring in regions of observed temperature increases, and that these temperature increases at continental scales cannot be explained by natural climate variations alone. Given the conclusions from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report that most of the observed increase in global average temperatures since the mid-twentieth century is very likely to be due to the observed increase in anthropogenic greenhouse gas concentrations, and furthermore that it is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent except Antarctica, we conclude that anthropogenic climate change is having a significant impact on physical and biological systems globally and in some continents.
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