Squash-preparation cytology from nasopharyngeal masses in the cat: cytological results and histological correlations in 30 cases

Upper airway obstruction in cats can be a life-threatening condition. Early recognition of clinical signs and an appropriate diagnostic approach increases the possibility of appropriate therapeutic choices. The purpose of this study was to assess the efficacy and diagnostic value of squash-preparation cytology in providing an accurate diagnosis of masses growing in the nasopharynx of cats. Cytological specimens prepared by a squash technique from nasopharyngeal masses in 30 cats were collected under direct endoscopic guidance and classified into four groups: benign inflammatory/hyperplastic mass, lymphoma, carcinoma and sarcoma. The cytopathological diagnosis was compared with the final histopathological diagnosis and indices of diagnostic test accuracy were calculated. The results showed good agreement between the cytological and histological diagnosis with a sensitivity of 0.94, a specificity of 0.81, a positive likelihood ratio of 0.9, a negative likelihood ratio of 0.9 and an overall accuracy of 0.9. Squash-preparation cytology is considered an accurate diagnostic tool for distinguishing benign from malignant nasopharyngeal masses in cats. For differentiation of lymphoma and lymphoid reactions histopathological confirmation is recommended.     

Characterization of the diffuse mucosal associated lymphoid tissue of feline small intestine

Characterization of the feline intestinal mucosal associated lymphoid tissue (MALT) will facilitate investigation of intestinal disease in the cat and promote the cat as an animal model for a range of human diseases which involve the intestinal lymphoid tissue. This includes inflammatory bowel disease, viral and non-viral associated intestinal lymphomas and immunodeficiency associated syndromes. Morphologic and phenotypic characterization of the normal small intestinal diffuse MALT in 22 SPF cats was performed using flow cytometry and cytology on isolated intestinal leukocytes from the intra-epithelial and lamina proprial compartments, as well as immunohistology on tissues from the feline duodenum, jejunum and ileum. The intra-epithelial compartment (IEC) was dominated by lymphocytes (>85%) which frequently contained intracytoplasmic granules. The most striking findings in the IEC were the elevated percentages of CD8 alpha+ lymphocytes (40%), presumed to express CD8 alpha alpha chains, and CD4-/CD8- (double negative) lymphocytes (44%), and the consistent presence of a minor subpopulation of CD3+/CD11d+ IELs (6%). Small percentages of CD4+ lymphocytes (10%) were observed such that the IEL CD4:CD8 ratio (0.25) was low. The LPC also contained a majority of T cells and few plasma cells. However, this compartment had reduced percentages of CD8 alpha+ lymphocytes (28%) and increased percentages of CD4+ lymphocytes (27%) relative to the IEC. However, the LPL CD4:CD8 ratio (1.0) remained low compared with the ratio in peripheral blood. In feline MALT, MHC class II expression was lower than in other peripheral lymphoid compartments. The results of this study provide important reference values for future investigations involving feline intestinal lymphocytes and demonstrates that the leukocyte distribution and phenotypic characteristics of the feline diffuse MALT appear largely similar to the murine, rat and human counterparts.     

Feline gastrointestinal lymphoma: mucosal architecture, immunophenotype, and molecular clonality

Gastrointestinal lymphomas were identified in 120 cats between 1995 and 2006. Lymphomas were classified according to the World Health Organization (WHO) scheme. Cats with mucosal T-cell lymphoma (n = 84) predominated and had a median survival of 29 months. Mucosal T-cell lymphoma matched WHO enteropathy-associated T-cell lymphoma (EATCL) type II. Epitheliotropic T-cell infiltrates were present in 62% of cats and occurred as clusters or diffuse infiltrates of small to intermediate-sized T cells in villous and/or crypt epithelium. Similar lymphocytes infiltrated the lamina propria in distinctive patterns. Cats with transmural T-cell lymphoma (n = 19) had a median survival of 1.5 months. Transmural T-cell lymphoma matched WHO EATCL type I. Epitheliotropic T-cell infiltrates were present in 58% of cats. Large lymphocytes (n = 11), mostly with cytoplasmic granules (LGL-granzyme B+) (n = 9) predominated. Transmural extension across the muscularis propria characterized the lesion. Both mucosal and transmural T-cell lymphomas were largely confined to the small intestine, and molecular clonality analysis revealed clonal or oligoclonal rearrangements of T-cell receptor-γ in 90% of cats. Cats with B-cell lymphoma (n = 19) had a median survival of 3.5 months. B-cell lymphomas occurred as transmural lesions in stomach, jejunum, and ileo-cecal-colic junction. The majority were diffuse, large B-cell lymphomas of centroblastic type. In conclusion, T-cell lymphomas characterized by distinctive mucosal architecture, CD3 expression, and clonal expansion predominated in the feline gastrointestinal tract.     

Chronic diseases of the nose and nasal sinuses in cats: a retrospective study

In this retrospective study of 41 cats with chronic nasal disease diagnoses included nasal neoplasia (n = 19), idiopathic chronic rhinosinusitis (ICRS) (n = 12), nasopharyngeal polyps (n = 3), foreign bodies (n = 2), nasopharyngeal stenosis (n = 1) and nasal aspergillosis (n = 1). In 3 cats diagnosis could not be established despite thorough work-up. Gender, indoor or outdoor housing, quality or quantity of nasal discharge, bacteriological findings of nasal flushes, radiology and CT findings did not differ significantly between cats with neoplasia and cats with ICRS. Cats with neoplasia were older (3 - 15, median 11 years) and showed clinical signs for a shorter period of time (1 - 8, median 2 months) than cats with ICRS (age 1 - 13, median 7.5 years; signs: 1 - 36, median 5 months). In all cats with neoplasia a mass was detected rhinoscopically, while this was only seen in 30 % of cats with ICRS. The exact diagnosis has to be established by examination of biopsy samples. A combination of physical examination, imaging studies and rhinoscopy with cytological and histopathological examination of samples enhances the likelihood for a correct diagnosis.     

Nasopharyngeal diseases in cats: a retrospective study of 53 cases (1991-1998)

The records of 53 cats with nasopharyngeal disease were examined. Of the cats with nasopharyngeal disease, 49% had lymphosarcoma and 28% had polyps. Clinical signs in these cats were compared to 24 cats with nasal disease alone. Cats with only nasal disease more commonly had historical nasal discharge and sneeze, whereas cats with nasopharyngeal disease more often had stertorous respiration, phonation change, and typically reported less nasal discharge or sneeze. It is important to include nasopharyngeal disease in the differential diagnosis for cats with nasal discharge, sneeze, stertor, or phonation change.     

Cytomorphological and immunohistochemical features of lymphoma in ferrets

Twenty ferrets with histopathologically diagnosed lymphoma were classified cytomorphologically and immunohistochemically. According to site of origin, multicentric, gastrointestinal, mediastinal and cutaneous lymphomas accounted for 8 (40%), 9 (45%), 2 (10%) and 1 case (5%), respectively. According to the National Cancer Institute Working Formulation (NCI-WF), low-, high- and intermediate-grade lymphomas accounted for 4 (20%), 4 (20%) and 12 cases (60%), respectively. The 4 low-grade lymphomas showed no mitotic figures, whereas all 4 high-grade lymphomas exhibited > or = 3 mitotic figures (median,6). Higher grade thus appears to be associated with a higher number of mitotic figures. Immunohistochemical examination of 18 specimens, excluding 2 insufficient specimens, showed that 16 (88.9%) and 2 (11.1%) lymphomas were of T-cell origin and B-cell origin, respectively. According to the combination of the NCI-WF and immunophenotypes, all 4 low-grade lymphomas (2 multicentric, 1 gastrointestinal, and 1 cutaneous lymphoma) were classified as diffuse small lymphocytic lymphoma of T-cell origin. Of the 12 intermediate-grade lymphomas (6 multicentric, 4 gastrointestinal, and 2 mediastinal lymphomas), 11 were classified as diffuse mixed-cell lymphoma, and 1 as diffuse large cell lymphoma. Of these 11 lymphomas, 2 (both multicentric) were of B-cell origin, 7 (3 multicentric, 3 gastrointestinal, 1 mediastinal) were of T-cell origin, and 2 (1 multicentric, 1 mediastinal) were of unknown cell origin. The remaining 1 lymphoma (gastrointestinal) was of T-cell origin. All 4 high-grade lymphomas (gastrointestinal) were classified as diffuse immunoblastic lymphoma of T-cell origin.     

Histology, immunohistochemistry and ultrastructure of the equine tubal tonsil

The tubal tonsil of the horse surrounds the pharyngeal opening of the eustachian tube and is lined by pseudostratified columnar ciliated epithelium interspersed with areas of follicle-associated epithelium (FAE) heavily infiltrated by lymphocytes but devoid of goblet and ciliated cells. Scanning and transmission electron microscopy revealed microvillous cells and cells with features characteristic of M cells such as reduced microvilli or depressed bare surface, more numerous mitochondria, small vesicles and lysosomes, as well as vimentin filaments and epitopes specific for GS 1-B4 as previously seen in the nasopharyngeal tonsil. M cells were also identified in areas of respiratory epithelium not associated with lymphoid follicles and appeared to be the nasal mucosal counterparts of recently described intestinal villous M cells in the mouse. The underlying lymphoid tissue of the FAE was generally organized as solitary lymphoid follicles without germinal centres in contrast to the diffuse and large amount of organized lymphoid follicles with germinal centres that characterize the nasopharyngeal tonsil. CD8+ T and B-lymphocytes were much fewer than in the nasopharyngeal tonsil. High endothelial venules were mainly oriented towards the parafollicular area and contained much fewer endothelial pores and vesiculo-vacuolar organelles. Finally, scattered small clusters of mucus acini and striated muscles were other features that differentiated the tubal and nasopharyngeal tonsils.     

Computed tomographic evidence of bulla effusion in cats with sinonasal disease: 2001-2004

BACKGROUND: Sinonasal disease is common in cats; chronic inflammatory disease and neoplasia are diagnosed most frequently. Radiographic and computed tomographic (CT) findings in nasal disease have been reported, although involvement of other cranial structures has not been fully described to our knowledge. HYPOTHESIS: We hypothesized that neoplastic or inflammatory obstruction of the auditory tube associated with sinonasal disease could result in CT evidence of effusive bulla disease in affected cats. ANIMALS: 46 cats with sinonasal disease, 18 control cats. METHODS: CT images acquired in cats with (n = 46) and without (n = 18) sinonasal disease were reviewed for evidence of concurrent bulla effusion. CT findings of soft tissue or fluid opacity within the tympanic bulla or thickening of the bone of the bullae were considered evidence of effusive bulla disease. RESULTS: The prevalence of bulla effusion in cats with sinonasal disease was 28% (13/46) and was significantly higher than that observed in cats without sinonasal disease (1/18, P = .043). CT findings that were found in association with effusive bulla disease included imaging features of sinusitis and nasopharyngeal disease. The most common neoplasm associated with bulla effusion was nasopharyngeal lymphoma. Bulla effusion was not observed in any cat with nasal carcinoma. CONCLUSIONS AND CLINICAL IMPORTANCE: Findings of this study suggest that auditory canal dysfunction may play a larger role in feline sinonasal disease than was previously recognized. The implications of these findings for management of cats with chronic inflammatory or neoplastic sinonasal disease require further investigation.     

Neoplasia associated with feline immunodeficiency virus infection in cats of southern California.

Between 1988 and 1991, feline immunodeficiency virus (FIV) infection status was evaluated in 1,160 cats examined at an oncology referral and general practice in Los Angeles, California. Twenty-nine (2.5%) cats were FIV positive. Neoplasia was present in 18 of the 29 (62%) cats. Sampling for neoplasia was intentionally biased in the oncology referral group. However, 33% (6/18) of FIV-infected cats with neoplasia originated from the general practice. Three neoplastic processes were observed; myeloproliferative disease (MPD; 5/18), lymphoma (LSA; 5/18), and squamous cell carcinoma (SCC; 7/18). One cat had LSA and SCC. Extranodal sites of LSA were common (66%) in FIV-infected cats. Sites of LSA were submandibular and mesenteric lymph nodes, liver, kidneys, periorbital area, and diffuse (heart, pancreas, bladder). Sites of SCC were sublingual (n = 2), nasal planum (n = 3), nasal planum and eyelids (n = 1), and mandible (n = 2). Feline leukemia virus co-infection was observed in 17% (5/29) of FIV-infected cats. The FIV-infected cats with MPD were young (range, 8 months to 13 years; median, 4 years) and had short survival duration (2, 6, 21, 134, 249 days) even in response to aggressive treatment. The FIV-infected cats with LSA were older (median age, 8 years; range, 4 to 14 years) and survived 60 days if untreated. Cats administered chemotherapy survived 39, 45, 217, and 243 days; the latter 2 cats had partial remission of 2 months' duration. Older FIV-infected cats had SCC (median age, 12 years; remission range, 7 to 16 years) because of more frequent association of both diseases in older cats with outdoor environment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Histopathologic classification of 171 cases of canine and feline non-Hodgkin lymphoma according to the WHO

A retrospective collection of 171 lymphoid neoplasms (123 dogs and 48 cats) was classified according to the Revised European–American Lymphoma (REAL) classification, adopted in 2002 by the World Health Organization (WHO), to evaluate the WHO system for categorization of canine and feline neoplasms. Microscopic examination was performed after standard hematoxylin–eosin staining and immunohistochemical labelling for B (CD79a) or T (CD3) cell phenotypes. B-cell lymphomas were prevalent in dogs and T-cell lymphomas in cats. B-Large cell lymphoma (B-LCL) frequently showed plasmacytoid differentiation; notably, two canine plasma cell tumours (PCT) expressed both CD79 and CD3. There were difficulties in differentiating B-lymphoblastic lymphoma (B-LBL) from Burkitt-type lymphoma. Furthermore, intestinal T-cell lymphoma (ITCL) exhibited a huge morphologic variability. Finally, multicentric mature small and thymic T-cell lymphomas were diagnosed, although these categories are not codified by the WHO classification.     

Immunophenotypic and cytomorphologic subclassification of T-cell lymphoma in the boxer breed

The boxer breed is at high risk for developing lymphoma and, in contrast to the general canine population, is predisposed to the T-cell variant of the disease. The purpose of this study was to more accurately classify lymphoma in this breed. Clinical, cytomorphologic and immunophenotypic data were examined in 43 boxers with lymphoma. Twenty-five cases were collected prospectively and a further 18 cases were obtained retrospectively. Lymphomas were classified as multicentric (n=29), mediastinal (n=6) and intestinal (n=8). Of the 40 immunophenotyped samples, 34 (85%) were T-cell, 5 (12.5%) were B-cell and 1 was a non-B-cell non-T-cell lymphoma. Immunophenotypic subtyping was done on prospectively collected T-cell lymphoma samples (n=22) to differentiate CD4 (helper) from CD8 (cytotoxic) T-cell origin as well as to determine the T-cell receptor (TCR) expression (TCRalphabeta vs. TCRdeltagamma). Phenotypic expression was CD4+ (n=12), double negative (DN) (n=6), double positive (DP) (n=1) and CD8+ (n=1), respectively, while two samples had no interpretable result. 20/22 samples were TCRalphabeta+ with only 1 sample being TCRdeltagamma+ and 1 with no interpretable result. Cytomorphologic analysis was done on the same 22 samples using the World Health Organization (WHO) classification scheme. According to this scheme, 17/22 samples were classified as lymphoblastic, 2/22 as large cell peripheral T-cell lymphoma-not otherwise specified (PTCL-NOS), 2/22 as large granular lymphoma (LGL) high-grade and 1/22 as small lymphocytic. The results of this study indicate that lymphoma in the boxer breed is a disease comprised predominantly of TCRalphabeta+, CD4+ (helper) T-cells with lymphoblastic (high-grade) morphology.     

A rapid multiple immunofluorescence method for the simultaneous detection of CD20 and CD3 in canine and feline cytological samples

CD20 and CD3 are considered reliable markers for B and T cells, respectively. This study aimed to develop a rapid multiple immunofluorescence (RMIF) method for the detection of CD20 and CD3 on a single cytology slide. Air-dried smears were prepared using samples collected from dogs (n=26) and cats (n=6). Immunosignal detection using the newly developed method required 60 min. Clear immunosignals for CD20 and CD3 were detected in 24 of 26 samples in dogs and in all 6 cats. As the RMIF (CD20/CD3) method can detect markers of both B and T cells simultaneously on a single cytology smear, it would be an efficient tool for the immunophenotyping of canine and feline lymphoma samples.     

Chemotherapy with cyclophosphamide, vincristine, and prednisolone (COP) in cats with malignant lymphoma: new results with an old protocol

This retrospective study in 61 cats with malignant lymphomas examined the efficacy of a well-established chemotherapy protocol (cyclophosphamide, vincristine, and prednisolone [COP]) in the Netherlands, a country with a low prevalence of feline leukemia virus (FeLV). Twenty-two cats (36.1%) had mediastinal lymphoma, 11 (18.0%) had alimentary lymphoma, 7 (11.5%) had peripheral lymphoma, 8 (13.1%) had nasal lymphoma, and 13 (21.3%) had miscellaneous lymphoma (including renal lymphoma in 2 [3.3%]). Of the 54 cats that were tested, only 4 (7.4%) were FeLV positive. Complete remission (CR) was achieved in 46 of the 61 cats (75.4%). The estimated 1- and 2-year disease-free periods (DFPs) in the 46 cats with CR were 51.4 and 37.8%, respectively, whereas the median duration of remission was 251 days. The overall estimated 1-year survival rate in all cats was 48.7%, and the 2-year survival rate was 39.9%, with a median survival of 266 days. The median survival time and the 1-year survival rate for mediastinal lymphoma were 262 days and 49.4%. respectively. Siamese cats had a more favorable prognosis for survival and remission than other breeds. Response to therapy in this study was shown to be a significant prognostic indicator. CR is necessary for long-term survival. Cats that did not achieve CR had little chance of survival for longer than I year. Young Siamese cats in this study had a greater tendency to develop mediastinal malignant lymphoma at a young age, and all were FeLV negative. In comparison with results reported in other studies with different combination chemotherapy protocols, these are among the highest percentages of remission and the longest survival rates for cats with malignant lymphoma.     

Outcome and failure patterns of localized sinonasal lymphoma in cats treated with first‐line single‐modality radiation therapy: A retrospective study

Failure rate and site are not well defined in localized sinonasal lymphoma in cats treated with radiotherapy. In this study, we describe (a) failure pattern, (b) outcome, (c) influence of previously reported prognostic variables on the outcome in cats with suspected localized sinonasal lymphoma. In this multi‐institutional retrospective study, we included 51 cats treated with single‐modality radiotherapy. Cats were irradiated using 10x4.2Gy (n = 32), 12x3Gy (n = 11) or 5x6Gy (n = 8). Regional lymph nodes were prophylactically irradiated in 24/51 cats (47.1%). Twenty‐five cats (49.0%) developed progressive disease: progression was local (nasal) in five (9.8%), locoregional (nodal) in two (3.9%), local and locoregional in three (5.9%), systemic in nine (17.6%) and both local and systemic in six cats (11.8%). No cat receiving prophylactic nodal irradiation had progression in the locoregional lymph nodes. The median time to progression was 974 days (95%CI: 283;1666), with 58% and 53% of cats free of progression at 1 and 2 years, respectively. Median overall survival was 922 days (95%CI: 66;1779) with 61% and 49% alive at 1 and 2 years, respectively. Half of the cats that died of relapse/progression (13/26) died within 6 months of treatment, suggesting possible shortcomings of staging, rapid dissemination of disease or sequential lymphomagenesis. None of the prognostic factors evaluated were predictive of outcome (prednisolone use, anaemia, nasopharyngeal involvement, modified canine Adams tumour stage, protocol, total dose). Radiotherapy is an effective treatment for localized sinonasal lymphoma with a long time to progression. However, in one‐third of the cats, systemic disease progression occurs soon after radiotherapy.     

Lymphoid neoplasms in swine

Seventeen cases of lymphoid neoplasms in swine were investigated and divided into eight histological types. Cases 1-3 were precursor B lymphoblastic leukemias, which occurred in three piglets from the same dam. Cases 4 and 5 were diagnosed, respectively, as a precursor B lymphoblastic lymphoma and a thymic B cell lymphoma, because there were cytological differences between the lymphomas. These five cases of immature B cell malignancies expressed CD79a and terminal deoxynucleotidyl transferase (TdT). Mature B cell lymphomas were divisible into follicular (case 6), diffuse centroblastic (case 7) and intestinal large B cell (cases 8-11) lymphomas. Unlike in case 7, the neoplastic cells in cases 8-11 showed cytological features intermediate between centroblasts and immunoblasts. The mature lymphomas were characterized by positive immunolabeling for CD79a and cytoplasmic immunoglobulins. A case of thymic γδ T cell lymphoma (case 12) were positive for CD3, CD5, WC1 and TdT. Instead of TdT, perforin was expressed in γδ T cell lymphomas (cases 13-17), whose histological characteristics were epitheliotropism, homing into T cell zones of lymphatic tissues, and cytological atypia and pleomorphism. In the present study, lymphoid neoplasms could be classified into discrete histological types, some of which were considered to be specific for swine.     

Outcome of stereotactic body radiation for treatment of nasal and nasopharyngeal lymphoma in 32 cats

BackgroundThe safety and efficacy of stereotactic body radiation therapy (SBRT) in the treatment of localized nasal lymphoma in cats has not been described.HypothesisStereotactic body radiation therapy with or without adjuvant chemotherapy is an effective and well‐tolerated treatment for localized nasal lymphoma in cats.AnimalsThirty‐two client owned cats referred to Colorado State University for the treatment of nasal lymphoma.MethodsRetrospective study of cats treated with SBRT between 2010 and 2020 at Colorado State University. Diagnosis of nasal lymphoma was obtained via cytology or histopathology. Signalment, radiation protocol, concurrent treatments, adverse effects, and survival were recorded.ResultsProgression free survival was 225 days (95% CI 98–514) and median survival time (MST) was 365 days (95% CI 123–531). No significant difference in survival was identified between cats that received 1 versus greater than 1 fraction (MST 427 vs. 123 days, P = 0.88). Negative prognostic factors included cribriform lysis (MST 121 vs. 876 days, P = 0.0009) and intracalvarial involvement (MST 100 vs. 438 days, P = 0.0007). Disease progression was noted in 38% (12/32), locally in 22% (7/32), and systemically in 16% (5/32). No cats developed acute adverse effects. Ten cats developed late adverse effects: keratitis/keratitis sicca (n = 2), alopecia (n = 4), and leukotrichia (n = 4). Twenty‐four cats (75%) had signs consistent with chronic rhinitis.ConclusionsSBRT is effective and well tolerated for treating localized nasal lymphoma in cats. Outcomes for cats with lower stage disease (canine modified Adam''s stage 3 and lower) are comparable to historic data of cats treated with fractionated radiation therapy.     

Clinical, laboratory, and histopathologic features of equine lymphoma

Clinical, laboratory and tissue findings from 37 horses with lymphoma were investigated. Horses ranged in age from 0.3 to 20.5 years (median 5.0 years) and included 18 females and 19 males. Weight loss (n = 25) and ventral edema (n = 21) were the most common historical and physical abnormalities. The most common laboratory abnormalities were hyperfibrinogenemia (n = 26), hypoalbuminemia (n = 19), anemia (n = 19), leukemia (n = 14), hyperglobulinemia (n = 13), and thrombocytopenia (n = 13). Thirty-four tumors involved multiple lymphoid tissues and abdominal or thoracic organs, and 3 tumors were restricted to cutaneous and subcutaneous sites. Histopathologically, all tumors diffusely effaced normal lymph node architecture. Tumor cell morphology was heterogeneous in 17 tumors, and 8 tumors had marked histiocytic and multinucleated giant cell infiltrates. Extensive necrosis or focal fibrosis was present in 22 and 4 lymphomas, respectively. Staining of tumor sections with antibodies against CD3 and CD79alpha molecules resulted in classification of T-cell (n = 26) or B-cell (n = 7) origin. Four tumors could not be classified. Most T-cell tumors comprised small to medium CD3(+) lymphocytes, whereas 5 of 7 B-cell tumors were infiltrated by numerous small T lymphocytes and classified as T-cell-rich B-cell lymphoma. Neither estrogen nor progesterone receptor expression was consistently identified by immunochemical assessment of tumor tissues. Fresh tumor cells from 6 horses bound antibodies reactive with equine CD4, CD5, CD8, CD21, or major histocompatibility class II molecules, confirming T-cell (n = 5) or B-cell origin (n = 1). These findings suggest that T-cell lymphoma is more common than B-cell lymphoma in horses and that inflammation, possibly from tumor cytokine production, is frequent.     

Hemangiosarcoma in the cat: retrospective evaluation of 31 surgical cases

Hemangiosarcoma was diagnosed in 31 cats. Diagnosis was confirmed by surgical biopsy. Locations of the primary tumors were the abdominal cavity (15 cats), sc tissue (13 cats), thoracic cavity (2 cats), and nasal cavity (1 cat). Nine (60%) of the 15 cats with abdominal hemangiosarcoma had extrathoracic evidence of metastasis: this was not found in the other cats. Of the cats with tumors located in the sc tissue, 6 of 10 (60%) evaluated on a long-term basis had local recurrence of the tumor. Eleven cats were not available for follow-up evaluation, 3 cats were euthanatized at the time of surgery, and 2 others were euthanatized within the first postoperative week subsequent to histologic diagnosis of hemangiosarcoma. Of the remaining 15 cats, 4 with abdominal hemangiosarcoma and 5 with hemangiosarcoma of the sc tissue died at means of 22 and 44 weeks, respectively.     

Canine and feline retinal lymphoma: a retrospective review of 12 cases

This retrospective study identified 12 cases (6 canine and 6 feline) of ocular lymphoma with extensive retinal involvement and relative sparing of other ocular tissues. Our objectives were to describe the morphologic and immunohistochemical features of retinal lymphoma, assess the degree of correlation to the human counterpart, assign subtypes based on the veterinary‐adapted WHO classification system, and promote accurate reporting of retinal involvement in cases of intraocular lymphoma. Our findings suggest that a distinct retinal tropism is quite rare, representing approximately 1% of all cases of canine and feline ocular lymphoma. No breed or sex predispositions were identified. The mean age of the affected animal was 7 years (range 4–10) and 11 years (range 6–19) for dogs and cats, respectively. Nine cases (5 canine and 4 feline) were classified as diffuse large B‐cell lymphoma (DLBCL) subtype. The remaining cases were classified as peripheral T‐cell lymphoma (PTCL).     

A retrospective study of non-specific rhinitis in 22 cats and the value of nasal cytology and histopathology

Case records from 40 cats subjected to rhinoscopic examination for investigation of chronic nasal disease were reviewed. Cases in which no specific underlying cause (eg neoplasia) was detected were further selected for detailed retrospective study. In these 22 cats (55% of the initial population), a final diagnosis of non-specific chronic nasal disease was made. The radiographic, rhinoscopic, cytological and histopathological findings were reviewed. Mucosal biopsy specimens were obtained in 20 cases. Despite clinical signs of more than 4 weeks duration, histopathology indicated acute inflammation in four cases. Two cases had chronic lymphoplasmacytic inflammation and 14 had mixed (lymphoplasmacytic and neutrophilic) inflammation. Specimens for cytology were obtained from 17 cases by brush sampling. Three of these samples were not diagnostic due to the poor quality of the slides; one showed normal cytology. Acute inflammation was diagnosed by cytology (n=11) more commonly than chronic (n=1) or mixed inflammation (n=1). Concurrent samples, of quality suitable for both histopathological and cytological interpretation, were collected from 12 cases only. Cytological results were in agreement with the histological results in 25% of these cases, the main discrepancy being the nature of the dominant inflammatory cell type. Therefore cytology does not appear to be a reliable means for detection of chronic inflammation. Further studies are needed in order to investigate the correlation between the nature of mucosal inflammation as defined by both histological and cytological evaluation, and the relationship of these test results to prognosis and therapy.