Background
Splenic marginal zone lymphoma (MZL) is a form of indolent B‐cell lymphoma that is not well characterized in dogs.
Hypothesis/Objectives
The purpose of this study was to describe clinical ...characteristics and outcome in dogs with splenic MZL confirmed by histopathology, immunophenotyping, and molecular clonality assessment. We hypothesized that affected dogs would have prolonged survival time with splenectomy alone.
Animals
Thirty‐four dogs were included. Twenty‐nine dogs were diagnosed after splenectomy, and 5 dogs were diagnosed at necropsy.
Methods
Pathology records were searched for dogs with histologically confirmed splenic MZL. Clinical and outcome data were retrospectively collected by medical record review, and prognostic factors were evaluated. Histopathology was reviewed by a board‐certified pathologist, and tissue sections were subjected to immunophenotyping and molecular clonality assessment by PCR.
Results
Immunohistochemistry confirmed a B‐cell phenotype for all dogs. Molecular clonality assessment was performed in 33 of 34 dogs, of which 24 had clonal rearrangement of immunoglobulin (Ig) loci, 3 had pseudoclonal rearrangement, and 6 had polyclonal rearrangement. The overall median survival time (MST) for the 29 dogs that underwent splenectomy was 383 days. The MST for 14 of 29 asymptomatic dogs that underwent splenectomy for MZL was 1,153 days as compared to 309 days for 15/29 dogs with clinical signs referable to splenic MZL (P = .018). Lymph node involvement, hemoabdomen, anemia, chemotherapy, and concurrent malignancy did not affect survival outcome.
Conclusions and Clinical Importance
Dogs diagnosed with splenic MZL can have prolonged survival with splenectomy alone, without the use of adjuvant chemotherapy. Asymptomatic dogs may have a better survival outcome.
Background: Cerebrospinal fluid (CSF) in dogs with Hansen type I intervertebral disc herniation (IVDH) is classically described as normal or mildly inflammatory with a predominance of large ...mononuclear cells or neutrophils in severe acute herniations. However, we have observed a moderate to marked pleocytosis with a predominance of lymphocytes in some dogs with IVDH.
Hypothesis: Moderate to marked CSF pleocytosis occurs more commonly in dogs with type I IVDH than is reported in the literature. Lymphocytic predominance is more common than nonlymphocytic pleocytosis in dogs with chronic IVDH.
Animals: Four hundred twenty‐three client‐owned dogs with type I IVDH.
Methods: Retrospective study. Lumbar CSF of dogs with surgically confirmed type I IVDH was evaluated cytologically. Information obtained from medical records included signalment, prior clinical history, time from onset of signs to presentation, neurologic status, and intraoperative findings. Dogs with prior history and/or intraoperative evidence consistent with chronic IVDH before an acute herniation were termed acute‐on‐chronic (AOC).
Results: Pleocytosis (> 5 cells/uL) was present in 51% of dogs, including 23% with cervical IVDH and 61% with thoracolumbar IVDH. Moderate or marked inflammation (≥ 20 cells/uL) was identified in the CSF of 51% of dogs with thoracolumbar IVDH and pleocytosis. A predominance of lymphocytes was significantly more common in dogs examined > 7 days from onset of signs (P= .032) and in dogs with AOC IVDH (P= .0013).
Conclusions and Clinical Importance: Moderate to marked CSF pleocytosis in dogs with type I IVDH is more common than previously reported. Lymphocytic pleocytosis is most common in dogs with chronic progression or AOC IVDH. Lymphocytic inflammation in the CSF of some dogs might suggest an immune‐mediated response to chronically herniated disc material.
There is an increasing need for more accurate prognostic and predictive markers in veterinary oncology because of an increasing number of treatment options, the increased financial costs associated ...with treatment, and the emotional stress experienced by owners in association with the disease and its treatment. Numerous studies have evaluated potential prognostic and predictive markers for veterinary neoplastic diseases, but there are no established guidelines or standards for the conduct and reporting of prognostic studies in veterinary medicine. This lack of standardization has made the evaluation and comparison of studies difficult. Most important, translating these results to clinical applications is problematic. To address this issue, the American College of Veterinary Pathologists' Oncology Committee organized an initiative to establish guidelines for the conduct and reporting of prognostic studies in veterinary oncology. The goal of this initiative is to increase the quality and standardization of veterinary prognostic studies to facilitate independent evaluation, validation, comparison, and implementation of study results. This article represents a consensus statement on the conduct and reporting of prognostic studies in veterinary oncology from veterinary pathologists and oncologists from around the world. These guidelines should be considered a recommendation based on the current state of knowledge in the field, and they will need to be continually reevaluated and revised as the field of veterinary oncology continues to progress. As mentioned, these guidelines were developed through an initiative of the American College of Veterinary Pathologists' Oncology Committee, and they have been reviewed and endorsed by the World Small Animal Veterinary Association.
Sheep inoculated with a virulent South African strain of bluetongue (BT) virus serotype 4 developed severe clinical signs and lesions characteristic of fulminant BT, including coronitis, hemorrhage ...and ulceration of the mucosal lining of the oral cavity and forestomaches, hemorrhage in the wall of the pulmonary artery, and focally extensive necrosis of skeletal muscle, especially of the neck. At necropsy, up to 14 days after infection, the infected sheep exhibited striking pulmonary edema, edema of the subcutaneous tissues and fascial planes of the head and neck, and pleural and pericardial effusion of varying severity. A reliable model for experimental reproduction of fulminant BT in sheep will facilitate future studies to better characterize the pathogenesis of this disease, particularly as it regards the mechanisms responsible for the increased vascular permeability that characterizes BT and related orbiviral diseases such as African horse sickness.
To develop a molecular-based assay so that the diagnosis of feline B-cell neoplasia can be facilitated, we have characterized 24 feline immunoglobulin heavy chain variable region (IGH V) ...complementary DNA (cDNA) transcripts. Structural homology with rearranged human IGH V genes was found, and the sequence information was used to design a feline-specific polymerase chain reaction (PCR)-based assay to amplify the complementarity determining region 3 as a marker for B-cell clonality. Conserved primers derived from the second and third framework regions of V gene segments were used in conjunction with 2 sequence-specific primers and 1 degenerate primer derived from the J gene segments. Each PCR reaction was run in duplicate, and both native and denatured PCR products were evaluated using polyacrylamide gel electrophoresis. Formalin-fixed, paraffin-embedded (FFPE) tissue sections from cats with confirmed B-cell neoplasia (diffuse large B-cell lymphoma, plasmacytoma, and myeloma) were examined, and 15/22 (68.2%) cats produced results indicative of the presence of a monoclonal population of B cells. The evaluation of denatured PCR products (heteroduplex analysis) facilitated a more accurate interpretation in 3/15 (20%) cats. Pseudoclonality was a major reason for the failure to detect monoclonality. Poor DNA quality is a significant concern and was responsible for the removal of 2 cats from the study. Using this assay, FFPE normal feline lymphoid tissues and unfixed peripheral blood mononuclear cells were determined to be composed of polyclonal populations of B cells. This assay represents a useful adjunctive diagnostic tool for the diagnosis and investigation of feline B-cell lymphoproliferative disorders.
Prognostic Markers for Myeloid Neoplasms Juopperi, T. A.; Bienzle, D.; Bernreuter, D. C. ...
Veterinary Pathology,
01/2011, Letnik:
48, Številka:
1
Book Review, Journal Article
Recenzirano
Myeloid neoplasms include cancers associated with both rapid (acute myeloid leukemias) and gradual (myelodysplastic syndromes and myeloproliferative neoplasms) disease progression. Percentage of ...blast cells in marrow is used to separate acute (rapid) from chronic (gradual) and is the most consistently applied prognostic marker in veterinary medicine. However, since there is marked variation in tumor progression within groups, there is a need for more complex schemes to stratify animals into specific risk groups. In people with acute myeloid leukemia (AML), pretreatment karyotyping and molecular genetic analysis have greater utility as prognostic markers than morphologic and immunologic phenotypes. Karyotyping is not available as a prognostic marker for AML in dogs and cats, but progress in molecular genetics has created optimism about the eventual ability of veterinarians to discern conditions potentially responsive to medical intervention. In people with myelodysplastic syndromes (MDS), detailed prognostic scoring systems have been devised that use various combinations of blast cell percentage, hematocrit, platelet counts, unilineal versus multilineal cytopenias and dysplasia, karyotype, gender, age, immunophenotype, transfusion dependence, and colony-forming assays. Predictors of outcome for animals with MDS have been limited to blast cell percentage, anemia versus multilineal cytopenias, and morphologic phenotype. Prognostic markers for myeloproliferative neoplasms (eg, polycythemia vera, essential thrombocythemia) include clinical and hematological factors and in people also include cytogenetics and molecular genetics. Validation of prognostic markers for myeloid neoplasms in animals has been thwarted by the lack of a large case series that requires cooperation across institutions and veterinary specialties. Future progress requires overcoming these barriers.
Bone marrow (BM) pathology was assessed in 10 dogs with
Ehrlichia canis-induced aplastic pancytopenia. BM core biopsy sections were stained with haematoxylin and eosin and with haematoxylin/van ...Gieson and Gordon and Sweets' reticulin stain for the detection of collagen and reticulin fibres, respectively. Iron stores were assessed by Perls' Prussian blue staining. There was no significant deposition of collagen or reticulin in any sample, but in seven dogs the BM was depleted of haemosiderin. These findings suggest that myelofibrosis does not play a significant role in the development of BM failure in canine monocytic ehrlichiosis and that iron deficiency may exacerbate the anaemia in the myelosuppressive phase of the disease.
A 7‐year‐old male castrated Jack Russell Terrier was presented to the oncology service at the University of California–Davis Veterinary Medical Teaching Hospital for evaluation of suspected lymphoma. ...The dog had several enlarged lymph nodes and moderate lymphocytosis. Aspirates of an enlarged inguinal lymph node contained a bimorphic population of large immature lymphocytes and smaller cells with plasmacytoid features. Both cell types often contained a single large cytoplasmic inclusion that varied from clear to pale pink to sky blue. Cytologic changes were interpreted as most consistent with lymphoid neoplasia. Based on the predominantly mature cell morphology and some morphologic heterogeneity, the peripheral lymphocytosis was interpreted as most likely reactive in nature. However, the immunophenotype of the cells (CD20+, CD21+, CD79a+, MUM‐1+, and MHCII+) and clonality assays showed that tissue and blood lymphocytes were neoplastic B cells with clonal identity despite their different morphologic appearances. The cytoplasmic inclusions were positive with periodic acid‐Schiff and were immunoreactive for IgM and IgG. By transmission electron microscopy, inclusions consisted of aberrant rough endoplasmic reticulum; a few small Russell bodies were also noted. A final diagnosis of high‐grade B‐cell lymphoma with plasmacytoid differentiation, atypical cytoplasmic inclusions, and secondary leukemia was made. Chemotherapy was initiated, but the dog was euthanized due to severe and uncontrolled seizures 9 months after the initial diagnosis. This case extends the morphologic repertoire of canine plasmacytoid neoplasms and emphasizes their continuum with multicentric lymphoma. This case also demonstrates the need for advanced diagnostic techniques in establishing blood involvement in lymphoma in some instances.
Background: Serial arthrocentesis and synovial fluid examination can be used to monitor treatment efficacy in immune‐mediated polyarthritis (IMPA), but whether this procedure induces inflammation ...that interferes with test result interpretation is unknown.
Objectives: The aim of this study was to determine the effect of repeated arthrocentesis on synovial fluid cytology in healthy dogs.
Animals: Nine healthy client‐owned dogs.
Methods: Prospective study. Arthrocentesis was performed under sedation on 4 joints (both carpi, 1 tarsus, 1 stifle) on each dog every 3 weeks, a total of 4 times. Automated cell counts were done on stifle fluid, smears were made, and differential cell counts done on smears from all joints. Slides were evaluated microscopically for erythrocyte numbers, total nucleated cell count, differential cell count, and cell morphology. Data were analyzed by 2‐way analysis of variance.
Results: A total of 144 synovial fluid samples were examined. Repeated arthrocentesis was not associated with increases in synovial fluid neutrophil numbers. Mild mononuclear inflammation was detected in 13 samples from 6 dogs.
Conclusions and Clinical Importance: Serial arthrocentesis at 3‐week intervals can rarely be associated with mild mononuclear joint inflammation, but does not appear to induce neutrophilic inflammation, at least in healthy dogs, and can be useful to monitor treatment response in canine IMPA.
Hepatosplenic Lymphoma in a Dog Fry, M. M.; Vernau, W.; Pesavento, P. A. ...
Veterinary pathology,
09/2003, Letnik:
40, Številka:
5
Journal Article
Recenzirano
Odprti dostop
We describe a case of a dog with hepatosplenic lymphoma, a disease characterized by infiltration of the liver, spleen, and bone marrow with γδ T cells, absence of peripheral lymphadenopathy, and an ...aggressive clinical course. Physical examination findings, hematologic and biochemical abnormalities, and clinical course of the disease in this patient were similar to those in humans. Immunophenotyping of liver and spleen aspirates supported an antemortem diagnosis of T-cell lymphoma consistent with hepatosplenic lymphoma. The diagnosis was confirmed postmortem by a combination of routine histopathology, showing a consistent pattern of organ involvement, and immunohistochemistry showing the infiltrating neoplastic lymphocytes to be T cells expressing the γδ T-cell receptor. To our knowledge, this is the first reported case of hepatosplenic lymphoma in a dog.
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