Sonographic and computed tomographic features of intestinal mast cell tumors mimicking alimentary lymphoma in 2 dogs.

Two shih tzu dogs were referred to our clinic because of hematochezia and vomiting. Abdominal ultrasonography revealed a focal, asymmetric, exophytic small intestinal mass with loss of wall layering and muscular layer thickening of the adjacent intestine. Computed tomography (CT) in both dogs revealed a focal, asymmetric, homogenously contrast-enhanced exophytic jejunal and duodenal mass with an intact mucosal layer and generalized lymphadenopathy. Metastasis and ulceration were not detected on CT. The initial imaging diagnosis was lymphoma in both dogs; however, histopathological examination revealed the presence of intestinal mast cell tumors (iMCTs). Despite its similarity to alimentary lymphoma, iMCT should be considered a possible diagnosis, based on imaging characteristics, to ensure that proper treatments are selected. This is the first veterinary report describing detailed ultrasonographic and CT characteristics of iMCTs. Key clinical message: This is the first veterinary case report demonstrating sonographic and computed tomographic features of canine iMCT, which can be misdiagnosed as alimentary lymphoma. This report provides another differential diagnosis to consider when determining the appropriate patient treatment direction and histopathological examination.

Caractéristiques échographiques et tomodensitométriques de mastocytomes intestinaux imitant un lymphome alimentaire chez 2 chiens. Deux chiens shih tzu ont été référés à notre clinique en raison d'une hématochézie et de vomissements. L'échographie abdominale a révélé une masse focale, asymétrique et exophytique de l'intestin grêle avec perte de stratification pariétale et épaississement de la couche musculaire de l'intestin adjacent. La tomodensitométrie (TDM) chez les deux chiens a révélé une masse jéjunale et duodénale exophytique focale, asymétrique, homogène et contrastée avec une couche muqueuse intacte et une lymphadénopathie généralisée. Les métastases et les ulcérations n'ont pas été détectées par TDM. Le diagnostic initial d'imagerie était un lymphome chez les deux chiens; cependant, l'examen histopathologique a révélé la présence de mastocytomes intestinaux (iMCT). Malgré sa similitude avec le lymphome alimentaire, l'iMCT doit être considérée comme un diagnostic possible, basé sur les caractéristiques de l'imagerie, afin de garantir la sélection des traitements appropriés. Il s'agit du premier rapport vétérinaire décrivant les caractéristiques échographiques et tomodensitométriques détaillées des iMCT.Message clinique clé :Il s'agit du premier rapport de cas vétérinaire démontrant les caractéristiques échographiques et tomodensitométriques de l'iMCT canin, qui peuvent être diagnostiquées à tort comme un lymphome alimentaire. Ce rapport fournit un autre diagnostic différentiel à prendre en compte lors de la détermination de l'orientation thérapeutique et de l'examen histopathologique appropriés du patient.(Traduit par Dr Serge Messier).

Primary Intestinal Lymphoma in Rabbits.

Neoplasms of the intestinal tract are uncommon in rabbits and primary lymphoma of the intestinal tract is rare. This case series is the first detailed description of primary intestinal lymphoma in rabbits. We reviewed four cases of primary intestinal lymphoma in rabbits aged 5-9.5 years old with an average age of 7.8 years. Neoplastic cells in three cases were large (8 µm diameter) while one case had intermediate cells (5 µm diameter). Neoplastic lymphocytes were of B-cell lineage and characterized by intense, multifocal, membranous immunoreactivity for CD79a and no immunoreactivity to CD3. Based on the Revised European-American Classification of Lymphoid Neoplasms/World Health Organization classification, three of the cases were consistent with diffuse large B-cell lymphoma and the case with intermediate-sized neoplastic cells was consistent with lymphoblastic lymphoma.

Preliminary study of CT features of intermediate- and high-grade alimentary lymphoma and adenocarcinoma in cats.

CASE SERIES SUMMARY: The ultrasonographic findings of many feline intestinal tumours are similar. This study evaluated the CT features of intermediate- and high-grade alimentary lymphoma and adenocarcinoma in cats. CT was performed on six cats with adenocarcinoma and 14 cats with lymphoma. Comparisons between tumour types were conducted, focusing on CT features, including obstruction (present or absent), growth patterns of lesions (symmetry or asymmetry), layering enhancement (present or absent), location of the lesion, number of lesions (solitary or multiple), lymphadenopathy (present or absent), location of lymphadenopathy, pulmonary metastasis (present or absent) and maximum thickness (mm) of the lesion. The cats with adenocarcinoma (n = 5/6 [83%]) experienced intestinal obstruction significantly more often than cats with lymphoma (n = 0/14 [0%]; P = 0.0004). Layering enhancement was observed significantly more often in cats with adenocarcinoma (n = 6/6 [100%]) than in cats with lymphoma (n = 1/14 [7%]; P = 0.0002). Lymphadenopathy was detected significantly more often in cats with lymphoma (n = 14/14 [100%]) than in cats with adenocarcinoma (n = 2/6 [33%]) (P = 0.003). In cats with lymphoma, the intestine (12.1 ± 3.9 mm) was significantly thicker than that in cats with adenocarcinoma (6.4 ± 2.3 mm; P = 0.005). RELEVANCE AND NOVEL INFORMATION: To the best of our knowledge, no reports have described the characteristics of feline intestinal tumours using CT. Layering enhancement was observed in cats with intestinal adenocarcinomas. No layering enhancement was observed in alimentary lymphoma in cats, but enlarged regional nodes were noted. Lesions with lymphoma were thicker than those with adenocarcinoma. These findings may help differentiate between adenocarcinomas and lymphomas.

Intussusception caused by intestinal neoplasia in mature rainbow trout (Oncorhynchus mykiss, Walbaum 1792).

The aquaculture industry is growing and includes the farming and breeding of more than 580 aquatic species worldwide. The rainbow trout (Oncorhynchus mykiss, Walbaum 1792) is the most commonly bred trout species in Hungary. As broodfish form the basis of most fish farms, investigation into tumours occurring in trout, although under-researched, has proven to be a valuable and necessary field of study. During our investigation, we examined a broodstock of 3- to 6-year-old rainbow trouts (800) affected with idiopathic intestinal tumours (3%) which had consequentially led to ileus (40%). While performing necropsy, initial pathological observations showed intussusceptions. Tumours were discovered upon opening the body cavity, as well as metastasis forming in the livers and in the vessels of the gills. Histopathological and immunohistochemical tests allowed us to identify the neoplasms. The primary adenocarcinoma was found to have been developed within the intestines of the fish. The tumour tissue broke through the basal membrane and infiltrated the propria, protruding asymmetrically into the lumen of the mid-intestines, causing it to narrow significantly. This subsequently led to passage disorders, invagination of the intestinal segment and finally the emaciation of the fish. Histopathological and immunohistochemical inspection of the tumour cells displayed a high mitotic index, confirming malignancy.

Assessment of biomarkers influencing treatment success on small intestinal lymphoma in dogs.

This study aimed to determine a reliable therapeutic biomarker for localized small intestinal lymphoma (SIL) in dogs based on clinical and histopathological features. We retrospectively investigated 84 dogs with localized SIL, including 36 dogs receiving surgery and 48 dogs receiving chemotherapy. The dogs receiving surgery were divided into two subgroups: 18 dogs (group 1) with overall survival (OS) <120 days (median OS) and 18 dogs (group 2) with OS ≥120 days. Correspondingly, the dogs receiving chemotherapy were divided into 24 dogs (group 3) with OS <98 days (median OS) and 24 dogs (group 4) with OS ≥98 days. Clinical, haematological, histopathological and immunohistochemical analyses were comparatively evaluated among the four subgroups. There was no significant difference in OS between the surgery and chemotherapy groups. In dogs receiving surgery, the rate of Ki67-positive cells was significantly increased in group 1 compared to group 2 and showed no significant difference between groups 3 and 4. In dogs receiving chemotherapy, the rate of O6-methylguanine-DNA methyltransferase (MGMT) was significantly higher in group 3 than in group 4 and showed no significant difference between groups 1 and 2. Additionally, our data showed that OS in dogs with higher Ki67 expression might be significantly increased by chemotherapy than by surgery, that of those with higher MGMT expression might be significantly increased by surgery than by chemotherapy, and Ki67 and MGMT were independent of each other. Indices of Ki67 and MGMT are suggested therapeutic biomarkers to determine the optimal first-line treatment for localized SIL in dogs.

Intestinal T-cell lymphoma in a coati (Nasua nasua) - Short communication.

A 10-year-old female coati (Nasua nasua) was necropsied after an 8-day history of apathy, weight loss and dehydration. Gross changes consisted of multifocal to coalescing nodules ranging from 0.5 to 2.0 cm in diameter in the wall of the small intestine, adjacent to the mesentery and in the mesenteric lymph nodes. Histologically, neoplastic CD3-positive lymphocytes infiltrated all layers of the intestine, as well as the mesenteric adipose tissue and mesenteric lymph nodes. Based on the pathological and immunohistochemical findings, a diagnosis of intestinal T-cell lymphoma was made.

Intestinal ganglioneuroma in a neonatal Japanese black calf - Short communication.

A 1-day-old male calf presented with clinical signs of severe progressive abdominal distension. Abdominal radiographic and ultrasonic images revealed several loop-like structures in the small intestine, which were indicative of gas retention. Experimental laparotomy was performed. However, the calf died during surgery. At necropsy, a round, well-circumscribed mass (3 × 3 × 2.5 cm) was found in the jejunal wall, and the jejunal lumen was narrowed. The mass was firm and had white to grey appearance on the cut surface. Histologically, the submucosa and the muscle layer were diffusely thickened due to abundance of neural tissues comprising several fascicles of nerve fibres and large aggregates of ganglion cells. Some ganglion cells contained basophilic Nissl substances in their cytoplasm. Immunohistochemically, these cells were positive for S-100 and synaptophysin. Ultrastructural examination revealed that the neoplastic ganglion cells contained dense core vesicles in the cytoplasm. Based on these findings, the neoplastic lesion was diagnosed as ganglioneuroma in the jejunum.

Overexpression and Mutation of p53 Exons 4-8 in Canine Intestinal Adenocarcinoma.

p53 is mutated and overexpressed during malignant transformation, including in human colorectal cancer. This study investigated the overexpression of p53 protein and mutations in the p53 gene in canine intestinal neoplasia (CIN). Immunohistochemical analysis of p53 was carried out in formalin-fixed and paraffin wax-embedded (FFPE) sections of intestinal tissues from 35 dogs with CIN by the standard peroxidase-anti-peroxidase method. Expression of p53 protein in malignant (adenocarcinoma, n = 20) and benign (adenoma and polyp, n = 8) CINs was compared with tissue from negative controls (samples with no proliferation, n = 7). DNA was extracted from FFPE tissue from one control and 13 cases with overexpression of p53, and exons 4-8 were sequenced. p53 expression was higher in malignant than in benign tissues (P = 0.001). Sequencing was successfully performed in nine cases and mutations were confirmed in three of these cases. One non-sense mutation, one missense mutation and one germline mutation were confirmed for the three cases. This study suggests that p53 overexpression can be a prognostic factor for CIN; however, p53 overexpression in CIN may occur through a mechanism distinct from mutations within the p53 exon 4-8 region.

Equine Intestinal Lymphoma: Clinical-Pathological Features, Immunophenotype, and Survival.

Lymphoma is the most common intestinal neoplasm in horses, but its clinical-pathological features are poorly characterized. Primary intestinal lymphoma was diagnosed in 20 horses on biopsy samples and further confirmed by postmortem examination in 16 cases. Lymphoma was found in the small intestine in 12 of 20 (60%), in the colon in 5 of 20 (25%), and in both small and large intestines in 3 of 20 (15%) cases. Gross findings included thickening of the intestinal wall (45%), mural nodules or masses (30%), and both thickening and nodules (10%). Cases were classified according to the human World Health Organization classification as enteropathy-associated T-cell lymphoma (EATL) type 1 (40%), EATL type 2 (45%), and T-cell-rich large B-cell lymphoma (TCRLBCL) (15%). With respect to histologic grade, 70% of cases were grade 1 and 30% were grade 2. Of EATLs, the infiltrate was mucosal only (12%), mucosal and submucosal (53%), or transmural (35%). EATL1 was submucosal to transmural (2/8 and 6/8), EATL2 was mucosal to submucosal (3/9 and 6/9), and TCRLBCL was always transmural. Epitheliotropism was present in most EATLs and characterized by single-cell infiltrates within the epithelium in EATL1 and intraepithelial clusters or plaques in EATL2. Median survival was 25 days for EATL1, 90 days for EATL2, and 187.5 days for TCRLBCL; differences were not statistically significant. Of the EATLs, grade 1 had a median survival of 60 days and grade 2 had a median survival of 25 days; differences were not statistically significant.

Tumour-specific microRNA expression pattern in canine intestinal T-cell-lymphomas.

Intestinal T-cell lymphomas are common in dogs, but histopathological diagnosis remains challenging because of accompanying enteritis with lymphocyte involvement. Invasively taken full-layer biopsies are still required for reliable differentiation. The detection of specific microRNA expression patterns in canine intestinal T-cell lymphoma could provide new possibilities to differ intestinal lymphoma from benign inflammation and could lead to further understanding of lymphomagenesis. The objective of this study was to characterize microRNA expression in distinct groups of formalin-fixed and paraffin-embedded samples from canine intestinal T-cell lymphomas, lymphoplasmacellular enteritis and healthy intestinal tissue. In a preliminary test with two samples per group, total RNA was extracted (RNEasy FFPE Kit, Qiagen), reverse transcribed (miScript II RT Kit, Qiagen) and pre-amplified (miScript PreAmp PCR Kit, Qiagen). We performed comparative quantitative PCR on microRNA PCR Array plates (Qiagen) with pre-fabricated reactions for 183 different mature canine microRNAs. Subsequently, 12 microRNAs with conspicuous expression changes in the lymphoma group were selected and microRNA expression of all samples (n = 8) per group was analysed with individual microRNA assays (miScript Primer Assays, Qiagen) on the reverse transcribed RNA without pre-amplification. Our results revealed lymphoma-specific expression patterns, with down-regulation of the tumour-suppressing microRNAs miR-194, miR-192, miR-141 and miR-203, and up-regulation of oncogenic microRNAs, including microRNAs from the miR-106a~363 cluster. In addition, we detected only slight expression alterations between healthy intestinal tissue and lymphoplasmacellular enteritis cases. We conclude that microRNA expression patterns can be used to separate T-cell lymphomas from healthy tissue and benign inflammatory disorders.

Primary nonlymphoid gastrointestinal neoplasms in dogs in Rio Grande do Sul / Neoplasmas gastrointestinais primários não linfoides em cães no Rio Grande do Sul

Gastrointestinal neoplasms (GIN) are uncommon in dogs, but they mainly show malignant behavior and poor prognosis. The types of GIN in dogs and their frequency, as well as their epidemiological and histopathological characteristics were analyzed through a retrospective study of biopsies from 24.711 dogs from 2005 to 2017. Additionally, histological sections of neoplasms were subjected to immunohistochemistry (IHC) using antibodies against pancytokeratin, vimentin, smooth muscle actin, c-Kit, S-100, CD31, CD79αcy, and neuron-specific enolase. Of the total samples from dogs analyzed, 88 corresponded to GIN. Neoplasms occurred more frequently in purebred dogs (64.8%, 57/88), males (53.4%, 47/88), with a median age of 10 years. The intestine was affected by 84.1% (74/88) of the cases. Of these, the large intestine was the most affected (67.6%, 50/74). Most of the neoplasms had malignant behavior (88.6%, 78/88). Regarding the classification of neoplasms, 46.6% (41/88) of the diagnoses corresponded to epithelial, 46.6% (41/88) were mesenchymal, 5.7% (5/88) were hematopoietic, and 1.1% (1/88) was neuroendocrine. The most frequently diagnosed neoplasms were papillary adenocarcinoma (19.3%, 17/88), leiomyosarcoma (17.0%, 15/88), gastrointestinal stromal tumors (GISTs) (12.5%, 11/88), and leiomyoma (5.0%, 8/88). Adenocarcinomas were located mainly in the rectum, whereas leiomyosarcomas and GISTs developed mainly in the cecum. Epithelial neoplasms showed a greater potential for lymphatic invasion whereas mesenchymal neoplasms appeared to be more expansive with intratumoral necrosis and hemorrhage. Immunohistochemistry was found to be an important diagnostic technique for the identification of infiltrating cells in carcinomas and an indispensable technique for the definitive diagnosis of sarcomas.(AU)

Neoplasmas gastrointestinais (NGI) são pouco comuns em cães, mas possuem principalmente comportamento maligno e prognóstico reservado. Os tipos de NGI em cães e sua frequência, bem como características epidemiológicas e histopatológicas foram analisados por meio de um estudo retrospectivo dos exames de biópsias de 24.711 cães entre os anos de 2005 a 2017. Adicionalmente, cortes histológicos de NGI foram submetidos à técnica de imuno-histoquímica (IHQ), utilizando os anticorpos anti-pancitoqueratina, vimentina, actina de músculo liso, c-Kit, S-100, CD31, CD79αcy e enolase neurônio específica. Do total de cães analisados, 88 corresponderam a NGI não linfoides. Os neoplasmas ocorreram com maior frequência em cães de raça pura (64,8%, 57/88), machos (53,4%, 47/88), com mediana de idade de 10 anos. O intestino foi acometido em 84,1% dos casos (74/88). Destes, o intestino grosso foi o segmento mais afetado (67,6%, 50/74). A maior parte dos neoplasmas tinha comportamento maligno (88,6%, 78/88). Quanto à classificação, 46,6% (41/88) dos diagnósticos corresponderam a neoplasmas epiteliais, 46,6% (41/88) mesenquimais, 5,7% (5/88) hematopoiéticos e 1,1% (1/88), neuroendócrino. Os neoplasmas mais frequentemente diagnosticados foram adenocarcinoma papilar (19,3%, 17/88), leiomiossarcoma (17,0%, 15/88), tumor estromal gastrointestinal (GIST) (12,5%, 11/88) e leiomioma (12,5%, 8/88). Adenocarcinomas localizavam-se principalmente no reto, enquanto leiomiossarcoma e GISTs desenvolveram-se principalmente no ceco. Os neoplasmas epiteliais demonstraram um potencial maior de invasão linfática enquanto que os mesenquimais aparentaram ser mais expansivos, com necrose e hemorragia intratumorais. A imuno-histoquímica mostrou ser uma técnica diagnóstica importante para a identificação de células neoplásicas infiltravas no caso dos carcinomas e uma técnica indispensável para o diagnóstico definitivo de sarcomas.(AU)

Detection of the Bacteroides fragilis toxin gene in sheep with and without small intestinal adenocarcinoma.

Aims: To determine if presence of the Bacteroides fragilis toxin (bft) gene, a molecular marker of colonic carriage of entertoxigenic Bacteroides fragilis (ETBF) in humans, was associated with a finding of small intestinal adenocarcinomas (SIA) in sheep in New Zealand. Methods: Samples of jejunal tissue were collected from the site of tumours and from grossly normal adjacent tissue in 20 sheep, in different consignments, diagnosed with SIA based on gross examination of viscera following slaughter. Two jejunal samples were also collected from a control sheep in the same consignment that had no gross evidence of SIA. A PCR assay was used to detect the presence of the bft gene in the samples. Results: Of the sheep with SIA, the bft gene was amplified from one or both samples from 7/20 (35%) sheep, and in sheep that had no gross evidence of SIA the bft gene was amplified from at least one sample in 11/20 (55%) sheep (RR 0.61; 95% CI = 0.30-1.25; p = 0.34). Of 11 positive samples analysed, ETBF subtype bft-1 was detected in one, bft-2 was detected in 10, and none were bft-3. Conclusions and Clinical Relevance: There was a high prevalence of detection of the bft gene in both SIA-affected and non-affected sheep, but there was no apparent association between carriage of ETBF, evidenced by detection of the bft gene, and the presence of SIA. ETBF are increasingly implicated in the aetiology of human colorectal cancer, raising the possibility that sheep may provide a zoonotic reservoir of this potentially carcinogenic bacterium. Abbreviation: Bft: Bacteroides fragilis toxin; ETBF: Enterotoxigenic Bacteroides fragilis; SIA: Small intestinal adenocarcinoma.

Tumor microenvironment and stroma in intestinal adenocarcinomas and associated metastases in Atlantic salmon broodfish (Salmo salar).

Animal models are invaluable tools in cancer research. In this context, salmon is a promising candidate. Intestinal adenocarcinoma with metastases may be induced as a consequence of a plant-based diet triggering the inflammation - dysplasia- carcinogenesis pathway. Here, we investigate the stroma and the presence and nature of immune cells in such tumors by staining for mast cells, immunohistochemistry for T cells and antigen-presenting cells and in situ hybridization for B cells. In intestinal tumors, substantial amounts of T cells were detected in the stroma, whilst MHC class II+ cells were mainly among the cancerous cells. Ig+ cells were observed primarily in the tumor periphery. Mast cells showed a strong association with stroma. In metastases, scarce amounts of T cells were detected, whilst MHC I and II-reactivity varied, some tumors being completely negative. Ig+ cells were scattered around the metastatic tissue in no particular pattern, but were occasionally observed within clusters of tumor cells. Small numbers of mast cells were detected in the stroma. To the best of our knowledge, this is the first report addressing immune cells in fish tumors. The teleost tumor microenvironment seems comparable to that of mammals, making fish interesting model animals in oncoimmunology research.

Duodenal expression of antimicrobial peptides in dogs with idiopathic inflammatory bowel disease and intestinal lymphoma.

Although antimicrobial peptides (AMPs) play an integral role in the regulation of intestinal microbiota and homeostasis, their expression in canine gastrointestinal diseases, including idiopathic inflammatory bowel disease (IBD) and intestinal lymphoma, remains unknown. The objective of this study was to investigate the intestinal expression of AMPs in dogs with IBD or intestinal lymphoma. IBD was diagnosed in 44 dogs, small cell intestinal lymphoma in 25 dogs, and large cell intestinal lymphoma in 19 dogs. Twenty healthy beagles were used as normal controls. Duodenal mRNA expression of six representative AMPs - lactoferrin, lysozyme, cathelicidin, secretory leukocyte peptidase inhibitor (SLPI), bactericidal/permeability increasing protein (BPI), and canine beta defensin (CBD103) - was quantified by real-time reverse transcription polymerase chain reaction. The relative expression of BPI, lactoferrin, and SLPI was significantly higher in dogs with IBD and intestinal lymphomas than in healthy controls. Interestingly, the expression patterns of AMPs differed between dogs with IBD and those with intestinal lymphomas, especially small cell lymphoma. Increased expression of BPI differentiated IBD from dogs with small cell intestinal lymphoma, with a sensitivity of 93.2%, a specificity of 100%, and an area under the curve of 0.955. These results suggest that the expression patterns of AMP aid in the diagnosis of canine IBD and intestinal lymphoma, although it remains uncertain whether the altered AMP expression is the cause or effect of mucosal inflammation.

Anaplastic Large T-Cell Lymphoma in the Intestine of Dogs.

Anaplastic large T-cell lymphoma (ALTCL) is a rare subtype of non-Hodgkin T-cell lymphoma that occasionally occurs in the gastrointestinal tract of humans. Enteropathy-associated T-cell lymphoma (EATL) type 1 is the most common type of intestinal lymphoma in dogs, and ALTCL has not previously been reported in the intestinal tract of dogs. Thirteen dogs with intestinal masses diagnosed as intestinal lymphoma with anaplastic morphology were reviewed. Clinical data, including treatment protocols, were available for 11 cases. Immunohistochemistry for CD3, CD20, and CD30 was performed for all cases in addition to PCR for Antigen Receptor Rearrangements (PARR) for assessment of clonality. Eight (62%) of the cases presented with intestinal perforation, and all cases had 1 or more masses arising from the small intestine. Histologically, all cases were characterized by transmural infiltrates of large, CD3-positive and frequently CD30-positive cells. Neoplastic T cells had marked anisocytosis and anisokaryosis, prominent nucleoli, and occasionally indented to reniform nuclei. There was abundant necrosis and inflammation with occasional vascular invasion within neoplastic masses. All cases had a monoclonal T-cell receptor γ gene rearrangement. The median survival time was 5 days, with 1 dog surviving 2 years after the initial diagnosis. ALTCL can occur as an aggressive transmural lymphoma in the gastrointestinal tract of dogs and commonly causes intestinal perforation. ALTCL can be differentiated from EATL type 1 and might have implications for accurate prognostication and selection of therapeutic options in the future.

First description of Streptococcus lutetiensis from a diseased cat.

This paper describes for the first time the isolation of Streptococcus lutetiensis in a cat with intestinal lymphoma. The Streptococcus bovis group has undergone significant taxonomic changes over the past two decades and, in 2002, Poyart et al. described two distinct novel species within the genus Streptococcus: Streptococcus lutetiensis and Streptococcus pasteurianus. The bovis group streptococci include commensal species and subspecies or opportunistic pathogens of humans and animals. The cat was referred to the Veterinary Teaching Hospital, University of Bologna for chronic diarrhoea associated with fresh blood. A diagnosis of intestinal lymphoma was advanced. S. lutetiensis was accidentally isolated from the faeces of the cat and identified through MALDI-TOF and 16s rRNA sequencing. The Kirby-Bauer test revealed that the isolate was resistant to enrofloxacin, erythromycin, clindamycin, marbofloxacin and tetracycline. The detection of S. lutetiensis in cat faeces might suggest that it could be a normal inhabitant of cat intestinal tract or that it could be involved in the manifestation of intestinal diseases. Since bacteria belonging to the S. bovis group are considered emerging pathogens, additional research is required to evaluate the role of S. lutetiensis in cats and its role in the transmission of antimicrobial resistance. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study the isolation of Streptococcus lutetiensis from a cat with intestinal lymphoma was described for the first time. An antimicrobial susceptibility test performed by means of the disc diffusion method revealed that the isolate was resistant to enrofloxacin, erythromycin, clindamycin, marbofloxacin and tetracycline. Nowadays the ecological or pathogenetic role of S. lutetiensis in the gut of animals remains unclear but, even if its role as commensal bacterium was confirmed, the presence of multi-resistant S. lutetiensis in cat gut could favour the transmission of antimicrobial resistance to other bacteria.

Dual-phase computed tomography angiography of intestinal carcinoid tumor as a lead point for cecocolic intussusception in a dog.

In an 8-year-old Labrador Retriever with progressive anorexia, constipation, and depression, CT revealed intussusception of the cecum into the ascending colon and a small cecal mass showing strong enhancement on arterial phase. The ileocecocolic junction was surgically resected and histologically diagnosed as cecocolic intussusception with carcinoid tumor. The carcinoid tumor worked as a lead point of intussusception in this case. Dual phasic CT is useful to assess the presence of gastrointestinal tumors as lead points in old dogs with intussusception.

Evaluation of the histopathological extent of neoplastic infiltration in intestinal tumours in cats.

With the exception of intestinal lymphoma, surgery is the most commonly recommended treatment for solitary feline intestinal tumours. However, there is a lack of evidence to substantiate resection margin recommendations for these tumours. The aim of this study was to add knowledge concerning resection margins for discrete intestinal masses in cats. Thirty confirmed feline intestinal tumours removed at veterinary centres across the UK from March 2017 to March 2018 underwent histological assessment at the palpable edge of the intestinal tumour and then at every 1 cm increment to the surgeon-cut tissue border in oral, aboral and mesenteric directions. Histological margin recommendations were developed for carcinoma and lymphoma tumour types and non-lymphoma intestinal tumours collectively. Seventeen intestinal lymphomas, nine carcinomas, two sarcomas and two mast cell tumours were evaluated in this study. Seven of the nine intestinal carcinomas would have been completely removed with histological margins of 4 cm in oral and aboral directions. Both sarcomas and one mast cell tumour would have been removed in their entirety with 4 cm histological margins in oral and aboral directions. There was extensive and varied microscopic invasion of intestinal tissue away from discrete intestinal lymphomas in the majority of the cases in this study. There is increasing evidence in veterinary as well as human literature supporting the role of surgical resection in the treatment of discrete intestinal lymphoma. If surgery is to be considered this study supports the removal of the gross tumour only. A histological margin of 4 cm should be considered, where possible, for intestinal masses other than lymphomas.