Clinical characteristics and outcome of dogs with presumed primary renal lymphoma.

OBJECTIVES: To characterise the presentation, clinicopathologic data and outcome of 29 dogs with presumed primary renal lymphoma. MATERIALS AND METHODS: Retrospective analysis of medical records of dogs with suspected primary renal lymphoma from 11 institutions. RESULTS: All dogs were substage b, and lethargy and gastrointestinal signs were common presenting complaints, as were azotaemia (n=25; 86%) and erythrocytosis (n=15; 51%) on biochemical testing. Ultrasonography typically revealed bilateral renal lesions (n=23; 79%), renomegaly (n=22; 76%) and abdominal lymphadenopathy (n=14; 48%). Chemotherapy was the only treatment in 23 dogs, of which 11 responded, all considered partial responses. For all dogs the median progression-free survival and median overall survival times were 10 days (range: 1 to 126) and 12 days (range: 1 to 212), respectively, and for dogs that responded to chemotherapy 41 days (range: 10 to 126) and 47 days (range: 10 to 212), respectively. CLINICAL SIGNIFICANCE: Primary renal lymphoma in dogs appears to be associated with a poor prognosis and short-lived response to chemotherapy.

Prognostic significance of clinical presentation, induction and rescue treatment in 42 cases of canine centroblastic diffuse large B-cell multicentric lymphoma in the United Kingdom.

Canine lymphoma is a heterogeneous group of diseases and many previous studies have evaluated the response of a mixed population of lymphoma cases to one specific treatment protocol. The aim of this retrospective study was to describe the outcome and prognostic factors in 42 cases of multicentric centroblastic diffuse large B-cell lymphoma treated with either a COP-type (35%) or CHOP-type (64%) induction chemotherapy. The objective response rate to induction therapy was 94%; entire dogs had a greater rate of complete vs partial remissions than neutered dogs (P = .017). Median progression-free survival for the first remission (PFS1) was 182 days; absence of anaemia at diagnosis (P = .002) and pretreatment neutrophil:lymphocyte ratio (NLR) below 9.44 (P = .015) were independently predictive of longer PFS1. Fifty-eight percent of dogs received rescue protocols with an objective response rate of 81%; 31% of dogs received further rescue protocols (up to a total of 5) and the median number of protocols administered were 2. Median overall survival (OS) was 322 days, the 1-year survival rate was 38% and the 2-year survival rate was 9%. Lymphocyte:monocyte ratio above 1.43 (P = .031), NLR below 11.44 (P = .009), the combination of induction and rescue therapy (P = .030) and the total number of doxorubicin doses used (P = .002) were independently predictive of longer OS. Use of a COP-type protocol induction compared with CHOP did not undermine OS providing doxorubicin was used as rescue therapy.

Computed tomographic findings in 12 cases of canine multi-centric lymphoma with splenic and hepatic involvement.

OBJECTIVES: To describe the CT findings in a population of dogs with multi-centric lymphoma that involved the spleen and liver. MATERIALS AND METHODS: Clinical records between January 2008 and June 2015 were reviewed. Thoracic and abdominal CT examinations of patients diagnosed with multi-centric lymphoma were evaluated by a board-certified radiologist. A diagnosis of multi-centric lymphoma with splenic and hepatic involvement was based upon cytological identification and immunophenotyping of neoplastic lymphocytes in cellular samples harvested from a peripheral lymph node, the spleen and the liver. RESULTS: Twelve dogs were included in this study, of which 11 had B-cell lymphoma; immunophenotyping was inconclusive in one dog. The spleen appeared normal in seven dogs and nodules were identified in five dogs. Splenic nodules were hypoattenuating in four of five dogs and isoattenuating in one of five. After contrast administration, three of five appeared hypoattenuating and two of five isoattenuating. The liver appeared normal in 10 dogs and hepatic nodules were identified in two dogs. All hepatic nodules were isoattenuating before contrast and hypoattenuating following contrast administration. CLINICAL SIGNIFICANCE: The CT appearance of the spleen and liver was normal in the majority of dogs with multi-centric lymphoma. Fine needle aspiration of the spleen and liver is recommended when using CT to stage dogs with multi-centric lymphoma.

Clinical presentation, treatment and outcome in 31 dogs with presumed primary colorectal lymphoma (2001-2013).

The objective of this multicentre retrospective study was to describe clinical presentation, treatment and outcome and to determine prognostic factors for dogs with presumed primary colorectal lymphoma (PCRL). A total of 31 dogs were included. The predominant features of PCRL were high grade (n = 18) and immunophenotype B (n = 24). Most dogs were substage b (n = 25) with higher prevalence of haematochezia (n = 20). One dog had surgery only. Thirty dogs received chemotherapy; amongst them 13 had surgery or radiotherapy. Progression free survival (PFS) was 1318 days and disease-related median survival time (MST) was 1845 days. Fourteen dogs were alive at the end of the study with a median follow-up time of 684 days (3-4678 days). Younger dogs had longer PFS (P = 0.031) and disease-related MST (P = 0.01). Presence of haematochezia corresponded with longer PFS (P = 0.02). Addition of local treatment to chemotherapy did not significantly improve the outcome (P = 0.584). Canine PCRL has considerably longer PFS and MST than other forms of non-Hodgkin's lymphoma.

Retrospective evaluation of COX-2 expression, histological and clinical factors as prognostic indicators in dogs with renal cell carcinomas undergoing nephrectomy.

Limited veterinary literature is available regarding prognostic markers for canine renal cell carcinoma (CRCC). We retrospectively evaluated COX-2 expression, histological and clinical features associated with prognosis of CRCC. Sixty-four cases post-nephrectomy were included, 54 had histopathological assessment and 30 had COX-2 immunostaining performed. Eight dogs (13%) had metastatic disease at initial diagnosis. Twenty-seven dogs (42%) received adjuvant therapy after nephrectomy. On univariate analysis, COX-2 expression, mitotic index (MI), histologic type, vascular invasion, neoplastic invasiveness and metastasis at diagnosis were significantly associated with overall median survival time (MST). COX-2 score (COX-2 score > 3 MST 420 days versus 1176 days if COX-2 score <3; P = 0.011) and MI (MI > 30 MST 120 days versus 540 days for MI < 30; P = 0.003) were the only variables associated with CRCC outcome on multivariate analysis. The addition of MI and COX-2 immunostaining to standard histopathological evaluation would help predicting outcome in CRCC patients.

Prevalence of elevated alanine transaminase activity in dogs treated with CCNU (Lomustine)*.

The purpose of this study was to evaluate prevalence of serum alanine transaminase (ALT) elevation in dogs receiving lomustine (CCNU) and to analyse the pattern of occurrence and potential risk factors. Serum ALT activity in 109 dogs during single-agent CCNU chemotherapy was retrospectively analysed. The median initial dose, dose-intensity and cumulative dose of CCNU were 64 mg m(-2), 21 mg m(-2) week(-1) and 171 mg m(-2), respectively. The overall prevalence of major ALT elevation [> 5-fold upper reference limit (URL)] was 29% (32/109) and developed most commonly after one to three doses of CCNU. These ALT elevations occurred without preceding mild ALT elevation in 53% (17/32) of the cases. Three dogs (2.8%) developed clinical hepatopathy. For severe ALT elevation (>10-fold URL), age < or =5-year-old was associated with higher risk. The findings of this study showed that elevation of ALT is common during CCNU chemotherapy in dogs and severe elevation can develop on a sudden onset.

Postoperative bleeding in retired racing greyhounds.

BACKGROUND: Some retired racing Greyhounds (RRG) that undergo surgery bleed excessively. HYPOTHESIS: Greyhounds that bleed excessively will have one or more preoperative hemostatic abnormalities that can be used to predict the risk and severity of postoperative bleeding. ANIMALS: Eighty-eight RRG undergoing ovariohysterectomy or castration. METHODS: All dogs were evaluated preoperatively with a physical exam, CBC, platelet count, OSPT, APTT, platelet function with PFA-100(a); fibrinogen, d-dimer, plasminogen (Plmg), antiplasmin (AP), antithrombin (AT), and vWF concentration (vWF:Ag); vWF collagen binding assay (vWF:CBA), and Factor XIII assay. Assays were repeated in the dogs that bled, and in an age- and sex-matched control group of RRG. RESULTS: Twenty-six percent of the dogs had bleeding 36-48 hours after surgery. AP (P <.0001) and AT concentration (P= .007) were significantly lower, and vWF:CBA (P= .0284) was higher preoperatively in the dogs with excessive hemorrhage. A lower platelet count (P= .001) and hematocrit (P= .002), shorter OSPT (P= .0002) and higher plasma fibrinogen (P <.0001), and AP (P= .001) concentration were detected at the time of bleeding compared with preoperative values in the dogs that bleed excessively. The same findings were observed postoperatively for the control group, except for the decrease in hematocrit. CONCLUSIONS AND CLINICAL IMPORTANCE: The results indicate that this excessive postoperative bleeding is not attributable to a primary or secondary hemostatic defect, but could result from altered fibrinolysis.