M. Caniatti

Canine lymphoma: immunocytochemical analysis of fine-needle aspiration biopsy.

Cytospin preparations of fine-needle aspirates from 21 dogs with peripheral lymphadenopathy (18 with lymphoma and three with lymph node hyperplasia) were studied by combining morphologic and immunocytochemical analysis. Fine-needle aspirates were taken from at least two enlarged lymph nodes, and the diagnosis was based on air-dried smears stained with May-Grünwald Giemsa. Fine-needle aspiration biopsy always provided an adequate quality and quantity of cells to perform morphologic and immunologic studies. Immunophenotyping was performed on cytospin preparations with a panel of eight monoclonal antibodies specific for canine cell surface antigens and one rabbit polyclonal antibody (A452) against human CD3, which cross-reacts with dog antigen. The immunocytochemical study resulted in the diagnosis of 14 B-cell lymphomas (CD21 +, CD3-) and three T-cell lymphomas (all CD3 +, two CD8+). One lymphoma lacked surface antigens specific for the B- or T-cell lineage and was classified as non-B-non-T lymphoma (CD21-, CD3-, CD4-, CD8-). The monoclonal antibodies CA12.10C12, CA4.1D3, and CA1D6 and the polyclonal antibody A452, used as a group, appeared to be the most useful reagents to suggest lymphoid origin and to discriminate between T- and B-cell phenotype. Cytospin preparations in combination with immunocytochemistry provided a practical, economical, and accurate method for the diagnosis and phenotyping of canine lymphoma.

The Spectrum of Canine Cutaneous Perivascular Wall Tumors: Morphologic, Phenotypic and Clinical Characterization

Perivascular wall tumors (PWTs) are defined as neoplasms deriving from mural cells of blood vessels, excluding the endothelial lining. The spectrum of human cutaneous PWT includes glomus tumor, hemangiopericytoma (HEP), myopericytoma, angioleiomyoma/sarcoma, angiomyofibroblastoma, and angiofibroma. The purpose of this study was to revise clinical presentation, cytology, histopathology, and immunohistology of canine cutaneous PWT with cytology typical of canine HEP. Diagnosis was established on the basis of vascular growth patterns (staghorn, placentoid, perivascular whorling, bundles from media) and immunohistology, including 7 smooth muscle markers and the cell membrane ganglioside of unknown origin recognized by the antibody 3G5 (CMG-3G5). Twenty cases were included. Ages ranged from 6 to 13 years; 12 dogs were males and 8 were females, and there was a prevalence of crossbreeds. Tumors arose from a single site with preferential acral location (10/20). Cytology revealed moderate to high cellularity in all cases, cohesive groups of cells (19/20), capillaries (18/20), and bi- to multinucleated cells (18/20). Six myopericytomas, 5 angioleiomyomas, 2 angioleiomyosarcomas, 2 HEP, 1 angiofibroma, and 1 adventitial tumor were identified. A definitive diagnosis was not possible in 3 cases. Smoothelin, heavy caldesmon, desmin, myosin, calponin, and CMG-3G5 were the most valuable markers to differentially diagnose canine PWT. Similar to reports in humans, canine HEP embodied a spectrum of neoplastic entities arising from different vascular mural cells. Before canine PWTs are assimilated into one prognostic category, a consistent classification and characterization of their biology is necessary. As proposed in humans, HEP should also be considered a diagnosis of exclusion in dogs.

Feline Large Granular Lymphocyte (LGL) Lymphoma with Secondary Leukemia: Primary Intestinal Origin with Predominance of a CD3/CD8αα Phenotype

Clinicopathologic and immunophenotypic characteristics of large granular lymphocyte (LGL) neoplasia in 21 cats were examined. All cats were domestic short (19) or long hair (2) with a mean age of 9.3 years at diagnosis. Increased peripheral blood LGL counts were present in 18/21 cats. Neutrophilia (12/21 cats) and increased serum liver enzymes (7/12), total and direct bilirubin (7/13), BUN (5/14), and creatinine (2/14) were observed. Cats usually presented with advanced disease and none survived longer than 84 days (mean 18.8 days) postdiagnosis. Cytologically, LGLs had a mature (6/21), immature (13/21), or mixed (2/21) morphology. Necropsy lesions consisted of neoplastic lymphoid infiltrates in the jejunum, ileum, and duodenum in decreasing order of frequency. In the small intestine, mucosal ulceration (9/13) and epitheliotropism of neoplastic cells (9/13) were common. Neoplastic infiltrates were also present in the mesenteric lymph nodes (13/13), liver (12/13), spleen (8/13), kidneys (5/ 7), and bone marrow (5/7). A T cell phenotype (CD3∊+) characterized LGL neoplasia in 19/21 cases. A CD8αα+ cytotoxic/suppressor phenotype was present in 12/19 T cell tumors, 2 had a CD4+CD8αα phenotype, 3 had a CD4-CD8- phenotype, and 2 were CD4+ helper T cells. CD8β chain expression was not detected in any instance. In two cats, a B or T cell origin could not be established. CD103 was expressed by 11 of 19 (58%) of the lymphomas tested. The immunophenotypic features shared by neoplastic LGLs in the cat and feline intestinal intraepithelial lymphocytes (IELs) support a small intestinal IEL origin for feline LGL lymphoma.

Predictors of long-term survival in dogs with high-grade multicentric lymphoma

OBJECTIVE To determine factors predicting survival in dogs with high-grade multicentric lymphoma. Design-Retrospective cohort study. Animals-127 dogs with high-grade multicentric lymphoma evaluated at 4 veterinary hospitals from 2000 to 2009. PROCEDURES Records were reviewed to identify dogs with completely staged high-grade multicentric lymphoma treated with chemotherapy. Data collected included signalment, history, hematologic findings, tumor characteristics, treatment, and outcome. Long-term survival was defined as surviving > 2 years after diagnosis. Variables were analyzed for associations with dogs living > 2 years. RESULTS Among the 127 enrolled dogs, 13 (10%) survived > 2 years with a median survival time of 914 days (range, 740 to 2,058 days). Survival rates at 3, 4, and 5 years were 4%, 3%, and 1 %, respectively. At diagnosis, 11 of the 13 long-term survivors had a body weight ≥ 10 kg, PCV ≥ 35%, absence of ionized hypercalcemia, centroblastic lymphoma, immunophenotype B, absence of bone marrow involvement, and lymphoma stages I through IV and were not previously treated with corticosteroids. The same combination of factors was present in 26 of 114 (23%) dogs surviving ≤ 2 years, yielding a negative predictive value of 97.8% for long-term survivors. Four of the 6 long-term survivors that died during the study died of another cancer; 3 of them had osteosarcoma. CONCLUSIONS AND CLINICAL RELEVANCE Absence of the aforementioned combination of variables at diagnosis may help identify dogs with lymphoma that will not survive > 2 years. Other types of neoplasia, in particular osteosarcoma, may develop in long-term-surviving dogs.

Ultrasound-guided cytology of spleen and liver: a prognostic tool in canine cutaneous mast cell tumor.

BACKGROUND In the clinical staging of cutaneous mast cell tumors (cMCT), the diagnosis of metastasis is controversial based on cytological examination of lymph nodes, spleen, liver, bone marrow, and blood. OBJECTIVES To define the prognostic role of ultrasound-guided cytology of spleen and liver in cMCT. The results of cytological evaluation were compared in relation with survival time. ANIMALS Fifty-two client-owned dogs with a diagnosis of cMCT. METHODS Selection of cases was based on cytological evaluation of liver and spleen to detect infiltration at distant sites. The Kaplan Meier method was used to compare survival in dogs with and without infiltration of spleen and liver (log-rank test P < .05). RESULTS Ten dogs with cMCT had mast cell infiltration of spleen, liver, or both and 4 of these dogs had involvement of the regional lymph nodes. The majority of dogs had 2 or more ultrasonographically abnormal findings simultaneously in spleen and liver. Nine dogs had grade II cMCT, and 1 had grade III cMCT. Dogs with positive evidence of mast cell infiltration to spleen, liver, or both had shorter survival times (34 versus 733 days) compared with dogs negative for mast cell infiltration at distant sites. CONCLUSION AND CLINICAL IMPORTANCE Dogs with evidence of mast cell infiltration at distant sites have a shorter survival times than dogs without evidence of infiltration at distant sites. This study suggests that cytology of spleen and liver is indicated either for ultrasonographically normal or for ultrasonographically abnormal spleen and liver in dogs with cMCT.

Systemic gene therapy with anti-angiogenic factors inhibits spontaneous breast tumor growth and metastasis in MMTVneu transgenic mice

Tumor growth and metastasis are angiogenesis-dependent. The possibility of inhibiting tumor growth by interfering with the formation of new vessels has recently raised considerable interest. We previously reported that it is possible to inhibit primary tumor growth and metastasis in a transgenic model of spontaneous breast tumor, which shows many similarities to its human counterpart (including ability to metastasize) by intratumoral administration of a DNA construct carrying the murine angiostatin cDNA driven by liposomes. Here we report that it is also possible to achieve this goal by a systemic (intraperitoneal) delivery of therapeutic DNA constructs carrying genes coding for mouse and human anti-angiogenic factors which include angiostatin, endostatin and TIMP-2. These findings may be relevant to the design of therapeutic interventions in humans.

Multiple Endocrine Neoplasia Type-I-like Syndrome in Two Cats

Multiple endocrine neoplasia (MEN) embodies a group of diseases in human patients and domestic animals that are characterized by hyperplasia or neoplasia, or both, of two or more endocrine tissues. The MEN-1 syndrome is associated with menin gene mutations that induce various combinations of parathyroid, pituitary, and pancreatic endocrine tumors in humans. Two male, Domestic Shorthair cats developed symmetric alopecia, insulin-resistant diabetes mellitus, and pituitary-dependent hyperadrenocorticism at 12 and 13 years of age. Examination of skin biopsy specimens revealed atrophic dermatosis associated with hyperadrenocorticism. In one cat, cutaneous lesions consistent with paraneoplastic alopecia associated with pancreatic adenocarcinoma also were evident. Multiple invasive pancreatic beta cell carcinomas, pituitary corticotroph adenomas, and thyroid C-cell and parathyroid chief cell hyperplasia were diagnosed on the basis of results of gross, histologic, and immunohistochemical findings in both cats. Pancreatic exocrine adenocarcinoma was diagnosed in both cats. one cat also had hepatocellular carcinoma. Exons 1-8 of the feline menin gene were sequenced and were found to bear 93% homology with the human gene sequence, and the corresponding amino acid sequences shared 98% homology. Purification of total RNA and amplification of cDNA from lesional tissues to document mutations in the feline menin gene sequence were unsuccessful. The combination of lesions observed was consistent with the diagnosis of MEN-1-like syndrome in both cats.

Nasal rhinosporidiosis in dogs: four cases from Europe and a review of the literature.

This paper describes four cases of canine rhinosporidiosis which occurred in Italy in 1994 and 1995. Four dogs with a history of exposure to the muddy environment of rice fields, developed respiratory signs. Rhinoscopy revealed nasal polypoid lesions with a characteristic gross appearance due to the presence of multiple, tiny, white-yellowish spots representing sporangia filled with spores. In cytological samples obtained by brushing, many spores were present in an inflammatory background. Histologically, the polyps consisted of fibrovascular tissue embedding sporangia in different developmental stages, and free spores which elicited a severe pyogranulomatous inflammation. All the dogs were treated surgically and the condition did not recur in two cases during a years follow- up and in the other two cases during two years.

Clinicopathological Findings in Five Cats with Paw Calcification

This retrospective study describes the clinicopathological findings in five cats with soft tissue mineralisation of interdigital spaces and footpads. Paw disease was the reason for veterinary consultation in three out of five cats. All cats had laboratory findings suggestive of renal failure and high solubility product [calcium x phosphorus]. In all cases, cytological examination of paw lesions was suggestive of calcinosis. The results of our study agree with two previous case reports of paw calcification in the cat, suggesting a metastatic pathogenesis and a correlation between paw mineralisation and renal failure.

Analytical validation of the Sysmex XT-2000iV for cell counts in canine and feline effusions and concordance with cytologic diagnosis.

Background: The Sysmex XT‐2000iV is a hematology analyzer that combines laser and impedance technology. Its usefulness for determining cell counts in canine and feline intracavitary effusions has not yet been studied. Objectives: The objectives of this study were to evaluate the analytical performance of the Sysmex XT‐2000iV for cell counts in effusions from dogs and cats, and to assess correlation with an impedance counter and concordance with diagnoses based on cytologic findings. Methods: Effusions (43 pleural, 23 peritoneal, 6 pericardial) were analyzed from 32 dogs and 34 cats. Total nucleated cell count (TNCC), HCT, and RBC count were determined on the Sysmex and compared with those obtained on an impedance counter (Hemat 8, SEAC). Imprecision, linearity, and limit of detection were determined for the Sysmex. An algorithm was designed using quantitative and qualitative data from the Sysmex to classify the effusions and the results were compared with diagnoses based on cytologic findings. Results: Intra‐assay and interassay coefficients of variation on the Sysmex were variable. Linearity of TNCC was ≥0.993 for dogs and cats, with the exception of effusions from cats with feline infectious peritonitis, which had delta (Δ) TNC values >3.0. In comparison with the Hemat 8, a proportional error was found for TNCC on the Sysmex. Effusion classification based on the algorithm was concordant with that obtained by cytologic examination in 43/72 (60%) samples. Discordant results usually were due to the misclassification of cells with similar morphology (such as mesothelial and carcinoma cells) in Sysmex scattergrams. Conclusion: The Sysmex XT‐2000iV provides a precise and accurate TNCC and has moderate concordance with cytologic findings for classifying canine and feline effusions. Although microscopic examination of effusions is necessary to achieve an accurate diagnosis, the Sysmex can provide preliminary information that may be helpful to cytopathologists.