Histiocytic sarcomas in flat-coated retrievers: a summary of 37 cases (November 1998–March 2005)

Thirty‐seven cases of histiocytic‐like sarcomas (HLSs) in flat‐coated retriever dogs were evaluated retrospectively. This tumour accounted for 36% of the malignant tumours seen in this breed during the study period. The median age at presentation was 8.2 years. Thirty‐four dogs presented with a swelling or mass in a muscle group or surrounding a joint. The remaining three presented for rib (1), cutaneous (1) or primary splenic origin (1). A high rate of metastasis to local lymph nodes (45%), thorax (20%) and abdominal organs (20% confirmed) was seen. Overall metastastic rate by the time of death was 70%. The median survival for all dogs was 123 days. The most significant prognostic indicator was presence of distant metastasis at the time of diagnosis with median survival of 68 or 200 days, with or without metastasis, respectively. Chemotherapy and radiation therapy significantly improved survival. Dogs given chemotherapy survived a median of 185 versus 34 days for dogs that were not (P = 0.0008). Dogs treated with radiation survived a median of 182 versus 60 days for those that were not (P = 0.0282). Dogs receiving only palliative therapy survived a median of 17 versus 167 days in dogs receiving any kind of radiation, chemotherapy, surgery or combinations. A set protocol of radiation and CCNU (RTCCNU) induced minimal toxicity and provided a median survival of 208 versus 68 days for all other dogs. While this tumour carries a poor long‐term prognosis in flat‐coated retrievers, it is reasonable to treat these dogs for palliation of signs and extension of life.     

Oncologic outcome after curative-intent treatment in 39 dogs with primary chest wall tumors (1992-2005)

Objective— To describe the clinical features and determine oncologic outcome and prognostic factors for dogs with primary tumors of the osseous chest wall. Study Design— Historical cohort. Animals— Dogs (n=39) with spontaneous tumors involving the chest wall. Methods— Medical 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. Results— Of 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). Conclusion— Rib 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. Clinical Relevance— Osteosarcoma 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.     

Clinical characteristics, treatment, and outcome of dogs with presumed primary hepatic lymphoma: 18 cases (1992-2008)

OBJECTIVE-To determine outcome of dogs with presumed primary hepatic lymphoma treated with various multiagent, doxorubicin-based chemotherapeutic protocols and identify factors associated with prognosis. DESIGN-Retrospective case series. ANIMALS-18 dogs with presumed primary hepatic lymphoma. PROCEDURES-Medical records were reviewed for information on signalment, treatment, and outcome. RESULTS-8 dogs had a complete remission (CR), with a median remission duration of 120 days. Dogs with leukocytosis, neutrophilia, hypoalbuminemia, hyperbilirubinemia, or a combination of hypoalbuminemia and hyperbilirubinemia were less likely to achieve a CR. Overall median survival time (MST) was 63 days (range, 2 to 402 days). In a multivariate analysis, response to treatment and serum albumin concentration were associated with MST. Dogs that did not achieve a CR had a significantly shorter MST than did dogs that did achieve a CR (13 vs 283 days, respectively). Dogs with serum albumin concentration < 2.5 g/dL at the time treatment was initiated had a significantly shorter MST than did dogs with serum albumin concentration within reference limits (10 vs 128 days, respectively). There was also a positive correlation between serum albumin concentration and survival time (r = 0.74). CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that dogs with primary hepatic lymphoma that underwent chemotherapy had a poor prognosis, with a low response rate. Dogs that responded to treatment had a better prognosis, and dogs with hypoalbuminemia had a poorer prognosis.     

Comparison between symptomatic treatment and lomustine supplementation in 71 dogs with intracranial,space‐occupying lesions

Brain neoplasia is diagnosed in an increasing number of dogs. Consequently, there is a higher need for an effective treatment. Chemotherapy is considered in cases where surgery or radiation is not optional. The objective of this retrospective study was to evaluate the difference in median survival time (MST) of dogs with intracranial masses, treated symptomatically with corticosteroids and anti‐epileptic drugs, compared with the same symptomatic treatment supplemented with lomustine. The records of 71 dogs with intracranial masses were retrospectively evaluated. Fifteen dogs were treated symptomatically with corticosteroids and anti‐epileptics, and 56 dogs received additional therapy with lomustine. There was no statistically significant difference in MST between both groups, being 60 and 93 days, respectively. Age, duration of symptoms, intracranial localization of the mass and intra‐ or extra‐axial localization had no influence on survival time. However, female dogs survived significantly longer than male dogs.     

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

Objective— To characterize biologic behavior, clinical outcome, and effect of histologic grade on prognosis for dogs with appendicular chondrosarcoma treated by amputation alone. Study Design— Case series. Animals— Dogs (n=25) with appendicular chondrosarcoma. Methods— Medical 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. Results— Histopathology 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. Conclusion— Canine 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. Clinical Relevance— The overall prognosis for appendicular chondrosarcoma is better than that of appendicular osteosarcoma treated by amputation alone or in combination with chemotherapy.     

Evaluation of intracavitary mitoxantrone and carboplatin for treatment of carcinomatosis,sarcomatosis and mesothelioma,with or without malignant effusions: A retrospective analysis of 12 cases (1997–2002)*

Carcinomatosis, sarcomatosis and mesothelioma, with or without malignant effusions, are difficult to treat and generally carry a poor prognosis. The purpose of this study was two‐fold; first, to determine the prognosis for dogs with carcinomatosis, sarcomatosis, or mesothelioma, with or without malignant effusions; second, to evaluate the safety and efficacy of treatment with intracavitary (IC) carboplatin and mitoxantrone in dogs with these syndromes. Nineteen dogs were evaluated. Seven were untreated and 12 were treated with IC chemotherapy (mitoxantrone and/or carboplatin), and multiple factors were analysed for significance with respect to survival time. The median survival time (MST) for untreated dogs was 25 days, whereas the MST for treated dogs was 332 days (Log Rank, P < 0.0001). Treatment with IC chemotherapy was well tolerated. This study suggests that IC chemotherapy with mitoxantrone and/or carboplatin is an effective treatment for dogs with carcinomatosis, sarcomatosis or mesothelioma, with or without malignant effusion.     

Adjuvant carboplatin and gemcitabine combination chemotherapy postamputation in canine appendicular osteosarcoma

Background: Appendicular osteosarcoma (OSA), the most common bone tumor in dogs, is typically treated by amputation and adjuvant chemotherapy. Despite numerous efforts, the median survival time (MST) for dogs receiving a platinum compound, doxorubicin, or a combination of these remains at 8–12 months. Evidence from studies in mice suggests that gemcitabine has activity against OSA in vivo. Our preliminary work demonstrated that the addition of low‐dosage (10 mM) gemcitabine to carboplatin resulted in synergistic inhibition of OSA cell viability in vitro. Objective: The purpose of the following study was to determine whether the addition of low‐dosage (2 mg/kg) gemcitabine to carboplatin chemotherapy in dogs with OSA after amputation would improve MST over carboplatin monotherapy. Animals: Fifty dogs with histologically confirmed appendicular OSA. Methods: Dogs were treated prospectively with amputation and up to 4 dosages of carboplatin and gemcitabine in combination every 3 weeks. Results: The chemotherapeutic regimen was well tolerated with only 5 episodes of grade 3 or 4 hematologic toxicity. The median disease‐free interval (DFI) was 203 days and the MST was 279 for all dogs in this study. The 1‐ and 2‐year survival rates were 29.5 and 11.3%, respectively. Dogs with proximal humeral OSA had a shorter median DFI (P= .04) compared with dogs with OSA in other locations. Conclusions and Clinical Importance: These results are comparable to those reported for carboplatin monotherapy indicating that the addition of gemcitabine to carboplatin in dogs with appendicular OSA does not appear to improve outcome.     

Cortical allograft and endoprosthesis for limb-sparing surgery in dogs with distal radial osteosarcoma: a prospective clinical comparison of two different limb-sparing techniques

OBJECTIVE: To compare surgical and oncologic outcome in dogs with osteosarcoma (OSA) of the distal aspect of the radius treated with limb-sparing surgery, using either a cortical allograft or endoprosthesis, and postoperative chemotherapy; and to evaluate predictive factors for outcome. STUDY DESIGN: Prospective cohort study. ANIMALS: Dogs (n = 20) with spontaneous, non-metastatic OSA of the distal aspect of the radius. METHODS: Dogs were prospectively randomized for limb-sparing surgery with either a cortical allograft (n = 10) or endoprosthesis (10) and full-course adjuvant chemotherapy using single or dual agent protocols of cisplatin, carboplatin, and/or doxorubicin. Surgical (intraoperative findings, postoperative infection, construct failure) and oncologic (local tumor recurrence, metastasis, survival) outcomes were compared. The influence of intraoperative and postoperative variables on surgical and oncologic outcome were evaluated. RESULTS: No clinically significant differences in surgical and oncologic outcome were detected between groups. The percentage of radius replaced by the implant was significantly greater in the endoprosthesis group (60.9% compared with 48.6%, P = .008). Median survival time (MST) for dogs with construct failure, regardless of implant type, was 685 days and significantly greater than MST of dogs without construct failure (322 days, P = .042; hazard ratio [HR] 16.82). Median metastasis-free interval and MST (685 days versus 289 days; P = .034, HR 24.58) were significantly greater in dogs with postoperative infection. Disease-free and overall limb-salvage rates were 70% and 85%, respectively. Overall MST was 430 days. CONCLUSIONS: For dogs with OSA of the distal aspect of the radius, a cortical allograft or endoprosthesis can be used for limb-sparing surgery. Construct failure and postoperative infection significantly improve survival time regardless of implant type. CLINICAL RELEVANCE: An endoprosthesis is an attractive alternative to cortical allografts for limb-salvage of the distal aspect of the radius in dogs because surgical and oncologic outcomes are similar, but the endoprosthesis is an immediately available off-the-shelf implant which is not complicated by the bone harvesting and banking requirements associated with cortical allografts. Mechanisms whereby postoperative infection improves survival time requires further investigation and, if elucidated, may provide the opportunity to improve the outcome of dogs and humans with OSA.     

Xenogeneic murine tyrosinase DNA vaccine for malignant melanoma of the digit of dogs

Background: Malignant melanoma of dogs is a highly aggressive neoplasm and is the 2nd most common digit tumor. Metastatic disease is a common sequela for which few effective treatment options exist. Studies show that xenogeneic tyrosinase DNA vaccination yields immune responses and prolongation of survival in dogs with oral malignant melanoma. Objectives/Hypothesis: Describe clinical findings and tumor characteristics of a cohort of dogs with digit malignant melanoma, and evaluate the prognostic utility of a proposed staging system. Determine if a novel xenogeneic DNA vaccine is safe and potentially effective for treatment of dogs with digit melanoma. Animals: Fifty‐eight dogs with digit malignant melanoma treated at the Animal Medical Center between 2004 and 2007. Methods: Retrospective, medical records review of dogs with digit melanoma treated with xenogeneic DNA vaccine. Results: Overall median survival time (MST) for dogs treated with loco‐regional control and xenogeneic DNA vaccine was 476 days with a 1‐year survival rate of 63%. MST for dogs presenting with metastasis was 105 days versus 533 days for dogs presenting without metastasis (P < .0001). Forty‐eight percent of the dogs in the latter group were alive at 2 and 3 years. A proposed staging system proved prognostic with stages I–IV dogs surviving >952, >1,093, 321, and 76 days, respectively. Conclusions and Clinical Importance: The xenogeneic murine tyrosinase DNA vaccine was safe and appears effective when used in conjunction with local and regional disease control. The proposed staging system was prognostic in this study and future studies might benefit from utilizing this staging system.     

Outcome in dogs with advanced (stage 3b) anal sac gland carcinoma treated with surgery or hypofractionated radiation therapy

Stage 3b anal sac gland carcinoma (ASGC) can be life‐threatening. A surgical approach is not always possible or may be declined. Dogs with stage 3b ASGC treated with surgery or conformal radiation therapy (RT) with 8 × 3.8 Gy (total dose 30.4 Gy, over 2.5 weeks) were retrospectively evaluated. Patient characteristics, median progression‐free interval (PFI) and median survival time (MST) were compared. Twenty‐eight dogs were included; 15 underwent surgery, 13 underwent RT. At the time of presentation, 21% showed life‐threatening obstipation and 25% showed hypercalcaemia. PFI and MST for surgery cases were 159 days (95% CI: 135–184 days) and 182 days (95% CI: 146–218 days), both significantly lower than for RT cases with 347 days (95% CI: 240–454 days) and 447 days (95% CI: 222–672 days), (P = 0.01, P = 0.019). Surgery as well as RT led to a fast relief of symptoms. PFI and survival of surgical patients were significantly inferior to that of a comparable patient group treated with conformal hypofractionated RT.     

Clinical characteristics and outcome in dogs with small cell T‐cell intestinal lymphoma

Small cell intestinal lymphoma has not been well characterized in dogs. The objective of this study was to describe clinical characteristics and outcome in dogs with small cell intestinal lymphoma. We hypothesized that affected dogs would have prolonged survival compared with high‐grade gastrointestinal (GI) lymphoma. Pathology records were searched for dogs with histologically confirmed small cell GI lymphoma. Seventeen dogs with confirmed small cell intestinal lymphoma were identified, and clinical and outcome data were retrospectively collected. Histopathology was reviewed by a board‐certified pathologist, and tissue sections were subjected to immunophenotyping and molecular clonality assessment. All dogs had small cell, T‐cell, lymphoma confirmed within various regions of small intestine, with 1 dog also having disease in abdominal lymph nodes. All dogs had clinical signs attributable to GI disease; diarrhoea (n = 13) was most common. Ultrasonographic abnormalities were present in 8 of 13 dogs with abnormal wall layering (n = 7) and hyperechoic mucosal striations (n = 7) representing the most common findings. In total, 14 dogs received some form of treatment. The median survival time (MST) for all dogs was 279 days and the MST for the 14 dogs that received any treatment was 628 days. Dogs with anaemia and weight loss at presentation had significantly shorter survival times and dogs that received a combination of steroids and an alkylating agent had significantly longer survival times. Small cell, T‐cell, intestinal lymphoma is a distinct disease process in dogs, and those undergoing treatment may experience prolonged survival.     

Non-coagulopathic spontaneous hemothorax in dogs

Objective: To determine the history, clinicopathologic findings, underlying causes, and outcomes for dogs with non‐coagulopathic spontaneous hemothorax. Design: Retrospective case series. Setting: University referral hospital. Animals: Sixteen client‐owned dogs. Interventions: The medical records database was searched for dogs with hemothorax. Dogs with trauma, secondary coagulopathy, recent thoracic surgery, or pericardial intervention were excluded. For the remaining dogs, signalment, clinical signs, clinicopathologic findings, radiographic findings, histopathologic findings, interventions, and outcome were recorded. Measurements and main results: The most common presenting signs were tachypnea (n=9) and lethargy (n=5), typically of <1‐week duration. The most common cause of non‐coagulopathic spontaneous hemothorax in dogs was neoplasia, which was diagnosed in 14 patients (88%). Identified malignancies included hemangiosarcoma (n=1), malignant mesothelioma (n=1), metastatic ovarian carcinoma (n=1), osteosarcoma (n=2), and pulmonary carcinoma (n=2). An intrathoracic mass was visualized in 7 other dogs; however, histopathology was not obtained. Pancreatitis and lung lobe torsion were each diagnosed in 1 dog, and survival was prolonged with both surviving at least 1 year post discharge. Only 6 of 14 dogs that were diagnosed with neoplasia were discharged from the hospital. For the 4 dogs with cancer with available outcome data, median survival time was 16 days (range 1–70 days). Two dogs were lost to follow‐up and had unknown survival times. Conclusions: The development of non‐coagulopathic spontaneous hemothorax warrants a high‐index suspicion for neoplasia, in particular thoracic wall neoplasia.     

Canine spinal meningiomas and nerve sheath tumours in 34 dogs (2008‐2016): Distribution and long‐term outcome based upon histopathology and treatment modality

The purpose of this retrospective, multicentre case series was to describe the outcome following surgery and/or radiation of spinal meningiomas and nerve sheath tumours (NSTs) based upon treatment modality, with a specific aim to evaluate the survival times and time to recurrence following treatment for each histopathological diagnosis. Our hypothesis was that the addition of radiation therapy modalities to treatment will yield longer time to recurrence of clinical signs and survival time. Thirty‐four dogs met the inclusion criteria of histopathologically diagnosed extramedullary spinal meningioma or NST. Sixteen extramedullary spinal meningiomas and 18 NSTs were diagnosed. A diagnosis of meningioma was associated with a significantly longer survival time compared with NSTs, with median survival times (MST) of 508 days (95% confidence interval [CI]: 66‐881) vs 187 days (95% CI: 76‐433; P = .02). Dogs (seven) treated with stereotactic radiation therapy (SRT) for recurrence after surgery alone or SRT alone as their initial treatment gained an additional 125 to 346 days survival time.     

Doxorubicin chemotherapy for presumptive cardiac hemangiosarcoma in dogs†

Sixty‐four dogs were treated with single‐agent doxorubicin (DOX) for presumptive cardiac hemangiosarcoma (cHSA). The objective response rate (CR + PR) was 41%, and the biologic response rate (CR + PR + SD), or clinical benefit, was 68%. The median progression‐free survival (PFS) for treated dogs was 66 days. The median survival time (MST) for this group was 116 days and was significantly improved compared to a MST of 12 days for untreated control dogs (P = 0.0001). Biologic response was significantly associated with improved PFS (P < 0.0001) and OS (P < 0.0001). Univariate analysis identified larger tumour size as a variable negatively associated with PFS. The high rate of clinical benefit and improved MST suggest that DOX has activity in canine cHSA.     

Evaluation of prognostic factors in the surgical treatment of adrenal gland tumors in dogs: 41 cases (1999-2005)

OBJECTIVE: To identify preoperative predictors of survival and assess intraoperative and postoperative complications and survival rates for dogs undergoing adrenalectomy. DESIGN: Retrospective case series. ANIMALS: 41 dogs that underwent adrenalectomy. PROCEDURES: Records were reviewed to collect data regarding preoperative variables. Intraoperative and postoperative variables were also recorded. Variables were evaluated for association with survival duration via log-rank analysis for categoric variables and by use of Cox proportional hazards. Median survival times were calculated by use of Kaplan-Meier life table analysis. RESULTS: 9 (22.0%) dogs did not survive to discharge. Intraoperative mortality rate was 4.8%. Overall Kaplan-Meier median survival time was 690 days. Variables significantly associated with shorter survival times included preoperative weakness or lethargy, thrombocytopenia, increased BUN concentration, increased partial thromboplastin time (PTT), increased aspartate transaminase (AST) activity, hypokalemia, intraoperative hemorrhage, and concurrent nephrectomy. Postoperative variables significantly associated with shorter survival times included pancreatitis and renal failure. In multivariate analysis, preoperative hypokalemia, preoperative increased BUN concentration, and concurrent nephrectomy were significantly associated with a shorter survival time. CONCLUSIONS AND CLINICAL RELEVANCE: A high mortality rate was associated with adrenalectomy in dogs; however, those that survived until discharge from a hospital had long survival times. Preoperative factors associated with a shorter survival time were weakness or lethargy, thrombocytopenia, increased BUN concentration, increased PTT, increased AST activity, and hypokalemia. Studies are needed to evaluate how treatment for these factors may affect or change outcome after adrenalectomy. Dogs with adrenal masses that require concurrent nephrectomy and cause intraoperative hemorrhage have a guarded prognosis.     

Quantification of circulating tumour cells over time in dogs with appendicular osteosarcoma

Enumeration of circulating tumour cells (CTC) has shown promise for prognostication and guidance of therapeutic decisions in human cancers. The objective of this study was to enumerate CTC over time in dogs with naturally occurring osteosarcoma (OSA), and to determine correlation with patient outcome. Twenty-six dogs with OSA and no evidence of metastatic disease at the time of amputation were enrolled. Dogs were assessed for lung metastases and CTC prior to and following amputation, and at each chemotherapy visit. Twenty-one dogs completed the study. Nineteen dogs were euthanized and two were alive and free of metastases. Overall survival time ranged from 88 to 1058 days (median survival time (MST) 374 days). Increased serum alkaline phosphatase activity, advanced age, and higher body weight were significantly associated with lower MST. Dogs with OSA had a mean of 356 (0 to 4443) CTC/10⁶ leukocytes. In 12 of 15 dogs that developed radiographic evidence of metastasis, a pre-metastatic CTC spike was retrospectively detectable on average 36.5 (1–100 days) days prior to metastasis and was associated with significantly shorter MST (301 ± 64 vs. 626 ± 55 days; p = .0107). In a multivariable analysis, dogs with a CTC spike were 10× more likely to die compared with those without. These results suggest that a spike in CTC frequency precedes detection of metastasis in dogs with OSA and is associated with shorter survival. More frequent enumeration of CTC in a larger cohort of dogs with OSA may be warranted.     

Long-term survival and risk factors associated with biliary surgery in dogs: 34 cases (1994-2004)

OBJECTIVE: To determine factors associated with long-term survival after biliary surgery in dogs. DESIGN: Retrospective case series. ANIMALS: 34 dogs that underwent biliary surgery. PROCEDURES: Data extracted from medical records included sex, breed, body weight, age at surgery, history and clinical examination findings, preoperative and postoperative CBC, serum biochemical panel and coagulation profiles results, abdominal ultrasonographic findings, results of bacteriologic culture and histologic examination, surgical findings, postoperative complications, and survival time. Follow-up information was obtained from medical records or phone conversations with owners and referring veterinarians. RESULTS: Primary biliary findings included gallbladder mucocele (n = 20 dogs), inflammatory diseases (4), trauma (3), and neoplasia (1). Secondary biliary diseases included pancreatitis (n = 4), pancreatic neoplasia (1), and duodenal perforation (1). One- and 2-year survival rates were both 66%. Increasing age; gamma-glutamyltransferase activity; preanesthetic heart rate; BUN, phosphorus, and bilirubin concentrations; and the use of biliary diversion procedures were risk factors for death, although pancreatitis was not. However, poor long-term survival was associated with pancreatitis. CONCLUSIONS AND CLINICAL RELEVANCE: Long-term prognosis was guarded after biliary surgery in dogs. However, dogs that survived the early postoperative period had good long-term prognosis. Dogs with pancreatitis had poor prognosis. Overall, the prognosis was worse for dogs that underwent a biliary diversion, compared with dogs that did not.     

A retrospective review of treatment and response of high‐risk mast cell tumours in dogs

This retrospective case series evaluates survival outcome of 94 dogs with high metastatic risk mast cell tumours (MCT). Patients were treated with a cytotoxic chemotherapy protocol or the tyrosine kinase inhibitor masitinib, in the presence of gross disease or as an adjunct to surgical resection of the primary tumour. In patients presenting with metastatic disease, surgical resection of the primary tumour with adjunctive therapy with any chemotherapy incurred a significant survival advantage [median survival time (MST): 278 days] compared to patients receiving chemotherapy without surgical excision of the primary tumour (MST: 91 days, P < 0.0001). Patients with a surgically excised Patnaik grade II tumour and high Ki‐67 in the absence of metastatic disease treated with vinblastine and prednisolone showed a significantly longer survival (MST: 1946 days) than those treated with masitinib (MST: 369 days, P = 0.0037). Further prospective case‐controlled clinical trials of high‐risk MCTs are required to make precise evidence‐based treatment decisions for individual patients.