Transmissible Venereal Tumor Research Articles

Pilot study: Understanding Canine Transmissible Venereal Tumor through its Transcriptional Profile

Canine transmissible venereal tumor (CTVT) is transmitted through the implantation of tumor cells. CTVT was the first tumor described with contagious characteristics and remains one of the few tumors with this capability. This study aimed to map the transcriptomic profile of CTVT to elucidate the potential mechanisms through which this tumor implants and evades host immune surveillance. For this study, 11 dogs aged ≥ 2 years diagnosed with CTVT were selected. Tumor biopsies were performed, RNA was extracted and converted into complementary DNA, followed by RT-qPCR analysis. The transcriptomic profile of CTVT revealed a wide array of differentially expressed genes. However, only the most relevant genes from an oncological perspective were discussed. IL-8, CXCL13, NCAM1, RNASEL, COROA1, and CBLB demonstrated potential associations with immune system evasion and transmission via implantation. Therefore, studying these genes may contribute to the development of targeted therapies that prevent contagion and immune evasion.

Evaluation of canine and feline tumors in Morocco: Results of a prospective observational study of 250 cases (2020-2023).

This work aimed to evaluate the histologic tumor types and patient characteristics of canine and feline neoplasias in Morocco. In a prospective, observational study, 250 tumor samples were collected from veterinary clinics in Morocco. For each case, breed, age, sex, neuter status, and tumor site and histotype were analyzed. Among the 250 tumors, 201 (80.4%) were from dogs and 49 (19.6%) from cats. Most common tumor location in dogs was the reproductive tract (36.8%), followed by skin and soft tissues (27.4%) and mammary gland (14.9%). In cats, most tumors originated from the skin and soft tissues (55.1%), followed by mammary gland (20.4%) and oral cavity (14.3%). Commonest canine histologic tumor types were transmissible venereal tumor (CTVT11Abbreviations: CTVT, Canine transmissible venereal tumor; PAS, Periodic Acid-Schiff; IHC, Immunohistochemistry; AR, Antigen Retrieval; n, number; SD, Standard deviation; WHO, World Health Organization; Vet ICD-O, The Veterinary International Classification of Diseases for Oncology Canine Tumors First Edition; SCC, Squamous cell carcinoma.) (31.8%) and mammary carcinoma (14.4%). Squamous cell carcinoma (34.7%) and mammary carcinoma (20.4%) represented the most frequent feline neoplasms. Median age of dogs and cats at diagnosis was 7 and 10 years, respectively. Gender distribution was even in dogs; in cats, females were overrepresented. Most cats and about half of dogs were mixed-breed. The evaluated canine and feline neoplasias show differences in their tumor types and patient characteristics when compared to populations from other countries, in part based on the high number of CTVT and - possibly solar-induced –feline skin tumors.

Surgical Management of Canine Transmissible Venereal Tumor with Adjunctive Chemotherapy Combination

One male and a female 2-year-old Neapolitan Mastiff dogs weighing 41 and 40 kg, respectively, were presented to the University Veterinary Teaching Hospital, Jos, Nigeria, with complaints of continuous bleeding from the prepuce and vulva which were first observed about 2 months before presentation. Clinical examination revealed preputial bleeding of the male dog and serosanguinous vulva discharges with the presence of palpable masses with multiple nodules that were cauliflower-like. Cytological evaluations of smears from preputial and vaginal swabs revealed characteristic round cells with large eccentric nuclei, large nuclear-cytoplasmic ratio, and intracytoplasmic vacuolations as well as anisocytosis and anisokaryosis. Based on these cytological features, a diagnosis of canine transmissible venereal tumor (CTVT) was made in each case. Blood samples were collected for hematology and clinical chemistry. Debulking of the masses was carried out under general anesthesia using atropine sulfate and chlorpromazine as pre-anesthetics and Ketamine hydrochloride as induction and maintenance anesthetics. Following debulking, the resulting defect was reconstructed and the surgical wound was managed by daily wound cleaning and the administration of vincristine sulfate (0.025 mg/kg) slowly intravenously, ivermectin (0.3 mg/kg) subcutaneously, and piroxicam (0.3 mg/kg) and 20% amoxicillin (20 mg/kg) intramuscularly. There were no observed known vincristine sulfate-associated adverse effects as the dogs recovered and were discharged 3-week post-tumor debulking with no recurrence within 6 months of follow-up examinations. The debulked mass histologically showed several sheets of round neoplastic cells with prominent nuclei, mitotic figures, and infiltrating lymphocytes. Based on these findings, a diagnosis of CTVT was further confirmed. The hemogram showed moderate leukocytosis at day 1 in the bitch with a mild left shift at days 1 and 14 while clinical chemistry showed a marked increase in alkaline phosphatase, moderate increase in serum creatinine, and mild hypoproteinemia. In conclusion, management of CTVT with adjunctive vincristine sulfate and ivermectin combination resulted in complete healing with amelioration of known associated adverse effects.

Comparative efficacy of two different treatment protocols for treatment of canine transmissible venereal tumour

Comparative efficacy of two different treatment protocols for treatment of canine transmissible venereal tumour

Evaluation of Serum Amino Acid and Carnitine Profile in Dogs with Transmissible Venereal Tumor

The presented study aimed to reveal the changes in serum amino acid and carnitine profiles in dogs with transmissible venereal tumor (TVT). The study material comprised 40 female dogs ranging in age from 3 to 5 years. The dogs were divided into two groups based on genital organ examinations. Group 1 (n=20) consisted of healthy dogs, while Group 2 (n=20) consisted of TVT-positive dogs. The definite diagnosis of transmissible venereal tumor was made based on the detection of intracytoplasmic vacuoles and numerous mitotic figures in the collected vaginal smear samples. Blood samples were taken from dogs in both study groups and serum was obtained. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for the determination of carnitine and amino acid profiles. The obtained data were compared using independent samples t-test. The serum amino acid profiles of Lysine, Aspartic Acid, Tyrosine, Asparagine, Alanine, Arginine, Citrulline, Glutamic Acid, Glycine, Methylglutaryl, Phenylalanine, and Ornithine were found to be lower in the TVT group (P

Tumor Cells and Microenvironmental Interaction in Natural Course of Canine Transmissible Venereal Tumor

Canine transmissible venereal tumors (CTVT) is a naturally occurring tumor that is mostly transmitted between dogs through coitus. This study aims to investigate the effect of CTVT on molecular expression and disease progression by studying the tumor microenvironment (TME). For this purpose, biopsy samples taken from ten female dogs were evaluated histopathologically and CTVT was diagnosed. The expression of markers such as CD163, CD68, CD44, TGF-beta and bFGF was evaluated by immunoperoxidase tests. Histopathologically, CTVT cells exhibited pleomorphism, ranging from round to polygonal. Some cells exhibited prominent vacuoles and hypochromatic nuclei, while others exhibited hyperchromatic nuclei containing mitotic figures within the thin fibrovascular wall. Immunohistochemically, TGF-beta and CD44 expression was higher in CTVT cells compared to CD68 and bFGF, while bFGF expression was higher in fibrocytes and spindle cells compared to other markers. The results indicate that CD44 and TGF-beta may play a pivotal role in fibrovascular processes, CD163 and CD68 may facilitate interactions between stromal components and mesenchymal cells, and bFGF, TGF-beta and CD68 may contribute to the arrest of tumoral progression and the initiation of the regression phase. These findings underscore the necessity for further studies to elucidate the role of markers at different stages of CTVT progression.

Divergent DNA methylation patterns and gene expression in MYC and CDKN2B in canine transmissible venereal tumors.

Canine transmissible venereal tumor (CTVT), a unique transmissible cancer in dogs, affects the external genitalia and potentially spreads to other parts of the body. While somatic mutations in oncogenic and tumor-suppressing genes are linked to CTVT development, the impact of DNA methylation, which affects gene expression, remains unclear. This study explored whether DNA methylation in the promoter regions of the MYC oncogene and CDKN2B tumor suppressor genes in CTVTs is associated with their expression, both at the gene and protein levels. To investigate promoter DNA methylation of MYC and CDKN2B in CTVTs, we analyzed frozen tissue samples from genital CTVT (GTVTs) and extragenital CTVT (ETVTs). Genomic DNA was extracted, bisulfite-treated, and analyzed using bisulfite polymerase chain reaction (PCR) and sequencing. The messenger RNA and protein of MYC and CDKN2B were also extracted and assessed by real-time PCR and Western blotting. Matching formalin-fixed, paraffin-embedded blocks were used for immunohistochemical staining to visualize protein distribution in GTVT and ETVT tissues. Although both GTVT and ETVT samples showed MYC promoter methylation, the extent of methylation differed significantly. GTVTs displayed a much higher degree of methylation, potentially explaining the more pronounced downregulation of MYC gene expression and reduction in c-MYC protein levels observed in GTVTs compared with ETVTs. Our data revealed a prevalent hypermethylation pattern in the CDKN2B promoter across both sample types. However, DNA methylation, which was expected to have a suppressive effect, did not correlate with gene/protein expression. GTVTs displayed high protein levels despite significantly reduced CDKN2B expression. Conversely, ETVTs maintained regular CDKN2B expression but exhibited reduced protein production, suggesting a complex interplay between methylation and expression in these tumors. MYC demonstrated a clear association between its promoter methylation status, gene expression, and protein levels; however, CDKN2B lacked this correlation, implying the involvement of methylation-independent regulatory mechanisms and highlighting the need for further investigation.

Cancer Stem Cell and Epithelial Mesenchymal Transition (EMT) in Canine Transmissible Venereal Tumour- A Preliminary Study

Background: Cancer stem cell (CSC) and Epithelial to Mesenchymal Transition (EMT) transforms conversion of normal cells in the tumor microenvironment into CSC which is the main cause of embryogenesis, carcinogenesis and metastasis. Methods: Nineteen canine patients with recurrent transmissible venereal tumor (TVT) and metastasis of inguinal lymph node were the subjects of present study. Preoperative work up and clinical staging involving radiography, ultrasonography, hematobiochemical analysis and histopathology or biopsy were done to confirm the type of cancerous tissue. Tumor tissues were collected in ice cold RPMI-1640 and phosphate buffer solution. Flow cytometry analysis was performed following established protocol from surgically excised tissue sample. Trypan blue dye exclusion test was done to quantify the live/dead cell count. CD24PE, CD44FITC, CD133APC and EpCAM antibody with conjugates were chosen markers for flow cytometry analysis. Result: Nineteen canine patients were diagnosed with Transmissible Venereal tumor (TVT) (common sexually transmitted disease in male dog) through biopsy of excised surgical tissue following Haematoxylin and Eosin staining protocol. Recurrence was seen even after adjuvant chemotherapy with Vincristine injection @ 0.25 mg/m2 at weekly interval for 5 weeks. Trypan blue dye exclusion test confirms 98% live cell count in transmissible venereal granuloma after digestion and incubation for flow cytometry. Flow cytometry analysis of the cells from the TVT showed surface biomarkers for EpCAM+ cells, EpCAM CD24+ cells, EpCAM CD44+ cells, EpCAM CD133+ indicating cells with CSC and EMT properties. Presence of CSC and EMT cells in this patient was responsible for chemoresistance, distant metastasis and recurrence. Identification of specific CSC in a malignant cancer will yields deeper insight into biological aspects of metastasis and formulation of targeted therapy in fighting with cancer.

Prevalence and distribution of transmissible venereal tumor in dogs from a rural community of Mexico

Objective: The aim of this work was to determine the rates of prevalence and recurrence of TVT infection in owned dogs, as well as the distribution of the disease, in Cuajinicuilapa, Guerrero, Mexico. Methods: This work was an observational, descriptive, longitudinal study. A TVT diagnosis was performed in all dogs in the community based on clinical records, a physical examination, and a cytological evaluation, and further confirmed by histopathology. Tissue samples were surgically obtained for histopathological analysis and, when required, to remove tumors and give treatment with vincristine; a GPS system was used to identify possible spatial groupings. All cases were re-evaluated one year after. Results: A prevalence of 5.15% was found in 1047 dogs (512 females and 535 males; 25 positive females and 29 positive males). TVT infection was more frequent in 2–3-years-old dogs. A spatial aggregation pattern was observed in the local cases. One year after, no lesions were found in the 29 animals treated. Conclusion: TVT is a common disease, and its distribution suggests its aggregation in certain areas of the locality. Further studies on the dynamics of dog populations in small cities are required.

Tumor venéreo transmissível em sistema respiratório superior de canino

Transmissible Venereal Tumor (TVT) is one of the most common neoplasms that affect dogs, it has no predilection for sex or breed, but it has a higher incidence in free-ranging dogs that have access to the street. Transmission occurs through the implantation of tumor cells, from one animal carrying the disease, to another, during intercourse or through contact between mucous membranes during the habit of licking the genitalia affected by the tumor. They generally present on the genitalia, and can also occur in extragenital regions, such as the snout, eye, mouth and subcutaneous tissue. The tumor has a multilobulated appearance, resembling a cauliflower, is friable, hemorrhagic and grows irregularly. The diagnosis is made through anamnesis, physical examination, tumor cytology and histopathology for the definitive diagnosis. The treatment of choice is chemotherapy with anvicristine sulfate, applied intravenously, weekly, always preceding a blood count to analyze the patient's general health status. Considering that TVT is not commonly described in the nasopharyngeal region of dogs, this work aims to report the case of a four-year-old Shitzu dog, which presented the tumor, with conformations not characteristic of a TVT in the nasopharyngeal region, diagnosed through tomography and histopathology of the tumor, removed after surgical incision.

Aspectos clínicos e terapêuticos de cães acometidos com tvt em cavidade nasal: relato de dois casos

Canine transmissible venereal tumor is a contagious neoplasm typically found on the external genital mucosa of dogs of both sexes; however, it can also occur in extragenital areas, such as the nasal cavity. It spreads through contact with damaged tissues or mucous membranes containing viable neoplastic cells, or through the hemolymphatic system. This study aimed to report two cases of canine transmissible venereal tumor in the nasal cavity of two intact male mixed-breed dogs. Both animals exhibited neoplasm in the nasal septum with oral involvement. Diagnosis in both cases was made through clinical and radiological assessments; the neoplasia was confirmed through cytological analysis. Radiological assessment showed retraction of the alveolar bone adjacent to the right premolars in the animal in Case 1, whereas in the animal in Case 2, it revealed an increase in volume in the dorsal portion of the skull, with radiopacity, extending to the frontal, incisive, and nasal bones, confirming lysis in these bones. Animal in Case 1 was subjected to chemotherapy with doxorubicin, however, it experienced recurrence in the oronasal region after some time of tumor remission, requiring treatment with vincristine and subsequent surgical resection. Considering Case 2, the animal responded well to treatment with vincristine sulfate. The animal in Case 1 was discharged 6 months post-procedure, whereas the animal in Case 2 had a good response to the treatment of choice. Clinical information on cases of canine transmissible venereal tumors in the nasal region is essential, mainly regarding therapeutic success, diagnosis, prognosis, and treatment duration.

Clinical, Radiographic and Rhinoscopic Features of Primary Intra-Nasal Transmissible Venereal Tumour in Four Dogs and its Treatment

Transmissible venereal tumours are contagious tumours that typically affects intact male and female canines. Four dogs were presented to Small Animal Out-Patient unit of Madras Veterinary College Teaching Hospital, Chennai with history of chronic unilateral epistaxis and sneezing. Leukocytosis with neutrophilia was a consistent finding in all dogs whereas the serum biochemical values where unremarkable. Lateral and dorsoventral radiograph of skull revealed space occupying lesion suggesting soft tissue mass in the nasal cavity. Rhinoscopy confirmed the presence of tumour mass occluding nasal passage. Nasal cytology revealed the presence of characteristic transmissible venereal tumour cells. Chemotherapy was initiated with Vincristine sulphate at the dose rate of 0.7 mg/m2. All the four dogs showed complete clinical recovery after four weekly doses of vincristine chemotherapy. Radiography repeated after four weeks confirmed the absence of space occupying mass in nasal cavity. The present study describes the clinical and diagnostic imaging changes in dogs with intra-nasal transmissible venereal tumour and its therapeutic management.

Extragenital transmissible venereal tumor in dog: case report

Transmissible venereal tumor (TVT) is a round cell neoplasm that affects dogs, mainly with access to the street, because tumor implantation happens during coitus or by intimate social interaction with another sick canid. It mainly affects the genital region, but there are extragenital reports. Thus, this work aims to report a case of TVT in the eyelid and cervical region of a dog, male, non-castrated, adult, SRD, with access to the street, without previous history, positive for cynomosis, which presented ectoparasites, penile bloody secretion with bulb volume increase, nodular tumor ulcerated in cervical region, left eye with third eyelid volume increase and some small nodules in upper eyelid. Through cytology and histopathology, TVT was diagnosed in the samples analyzed. For treatment, five sessions of chemotherapy with Vincristine sulfate were carried out, which the animal responded with an improvement in clinical signs one week after the first session. Therefore, the importance of cytology and histopathology for diagnostic confirmation of TVT and of care in the analysis of ocular and skin tumors is emphasized, because, even if the occurrence of this neoplasia is common only in the genital region, it can present itself in other locations.

Ocular canine transmissible venereal tumour: Report of three cases

AbstractThis study investigated three cases of transmissible venereal tumour in dogs. In Case 1, a 5‐year‐old male dog presented with an eye mass and penile growths, unresponsive to previous treatment. Case 2 involved a 4.5‐year‐old male dog with bilateral ocular masses and penile lesions. Case 3 featured a stray dog with ocular and skin masses. All cases were confirmed as transmissible venereal tumour through impression smear cytology. Treatment with vincristine sulphate resulted in significant remission, with complete recovery after the fourth injection. This study contributes valuable knowledge for veterinarians in diagnosing and treating transmissible venereal tumour in dogs, emphasising the significance of an approach to case management and careful consideration of the varying clinical manifestations of the disease.

Canine transmissible venereal tumour in Morocco: Clinical and pathological findings in 64 dogs – Insights from a descriptive epidemiological study (2020-2023)

Background: Canine transmissible venereal tumour (CTVT) is a widely spread, contagious neoplasm commonly found in dogs. Mostly affects the external genitalia, however, it may also exhibit unusual clinical presentations. Aim: To describe the epidemiology, clinical appearance, cytologic and histopathologic features of dogs with TVT in Morocco. Methods: Within the realm of a nation-wide study on canine and feline tumours in Morocco between September 2020 and March 2023, dogs with histologically diagnosed TVT were identified and data on epidemiologic, clinical as well as cytologic and histologic features compiled and analyzed. Results: A total of 64 cases of canine TVT were diagnosed. 52 dogs were cross-breed (81.2%) while 4 Siberian Huskies (6.2%) and 3 German shepherds (4.7%) were the most affected pure-breed dogs. Median age of dogs at diagnosis was 3 years (range, 1-10years) and male gender was more common (male:female ratio; 1.3:1). Tumour was located exclusively in the genital area in 58 cases (90.6%), whereas 6 dogs (9.4%) had an atypical occurrence of TVT with locations including skin and nasal cavity. Cytology allowed for an early diagnosis in 2 cases. Histology revealed no differences between the genital and extragenital forms. Immunohistochemistry was necessary in 4 cases and revealed positive staining for vimentin and Alpha-1-antitrypsin, negative marking for CD3, CD20 and AE1/AE3, and low cytoplasmic labeling for lysozyme. Conclusion: CTVT is a widely distributed neoplasm in Morocco, mostly showing presence in young, cross-breed, and oftentimes stray dogs. Adequate understanding of this tumour's epidemiological features is necessary for its management and eradication.

Immunohistochemical expression of vimentin, E-cadherin, and CD45 in natural cases of canine cutaneous round tumors.

Round cell tumors are common cutaneous lesions in dogs, with increased occurrence percentages among different skin tumors. This study aimed to investigate the frequency as well as gross and pathological characteristics of round cell tumors in natural cases of tumorous dogs in relation to breed, sex, and age. Moreover, it aimed to evaluate the immunohistochemical expression of a panel of immunohistochemical stains, including vimentin, E-cadherin, and cluster of differentiation (CD45) as an adjunct technique for the differential diagnosis of cutaneous round cell neoplasm. Data were collected from 64 dogs of both sexes (36 females and 28 males), various breeds, and different ages (8 months to 7 years). The histopathological nature of neoplastic growth was reported, and neoplasm prevalence was classified using age, sex, breed, and site on the body. We observed 48 cases of transmissible venereal tumors, 12 cutaneous histiocytomas, and 4 histiocytic sarcoma. Immunohistochemical characterization revealed an intense positive immunoreactivity for vimentin in transmissible venereal tumor cells and moderate positive immunoreactivity for E-cadherin and CD45 in cutaneous histiocytoma and histiocytic sarcoma cells. In conclusion, the canine transmissible venereal tumor was the most frequent form of round cell tumor; thus, a definitive cutaneous neoplasm diagnosis should be based on histopathological morphology and immunohistochemical findings.

Pathological, histochemical, and immune-histochemical studies on some canine-skin neoplasm at Sharkia province, Egypt.

Cutaneous neoplastic disorders are often observed in small mammal pets, such as dogs, regardless of their gender. An important objective of this work was to give a full account of the clinical, pathological, and immune-histochemical features of several skin tumors in dogs. This study was a case series in the hospital clinic, Faculty of Veterinary Medicine, Zagazig University, Egypt. Twenty-five dogs (14 males and 11 females) were examined clinically during the period from March 2022 to October 2023. The skin swelling was collected from affected animals and then subjected to a detailed histopathological study to record the different gross and microscopic findings and confirm the diagnosis by immunohistochemistry. Skin neoplasia in dogs was exposed to various clinical signs, and the dogs' ages ranged between 3 and 11 years. Concerning tumor features, the majority of neoplasms were malignant (65.52%) more than benign (34.48%). The study revealed the presence of 29 cases of dogs showed neoplasia with different prevalence rates including squamous cell carcinoma (13.79%), mast cell tumor (6.89%), basal cell tumors (10.34%), histiocytoma (6.89%), trichoepithelioma (10.34%), transmissible venereal tumor (10.34%), trichilemmoma (3.44%), scalp paraganglioma (3.44%), pilomatricoma (10.34%), malignant melanomas (17.24%), and miscellaneous cases as fat necrosis (6.89%), in males and females dogs with different histopathological lesions and immunohistochemistry expressions for pan-cytokeratin (CK), melanocyte-differentiation antigens (S100 protein), and synaptophysin. Malignant melanomas (17.24%) are the extremely common cutaneous tumors diagnosed in this study. Meanwhile, benign tumors such as trichilemmoma, trichoepithelioma, pilomatricoma, and paraganglioma are less frequent in dogs.

Transmissible venereal tumor and its successful treatment in canines

Transmissible venereal tumor and its successful treatment in canines

Evaluation of one-shot vincristine sulfate combined with surgical excision as a new regimen for treatment of canine transmissible venereal tumor

Objective: The purpose of this study was to investigate the effectiveness of surgical excision combined with a single shot of vincristine sulfate for treating transmissible venereal tumor (TVT) in dogs. Materials and Methods: Fifty-two dogs were divided randomly into two groups (n = 26). Dogs in Group I were treated surgically by debulking the tumorous mass, whereas dogs in Group II were subjected to a combination of surgery and a single injection of vincristine sulfate. Results: Female dogs showed a high prevalence of TVT compared to males (67.3%, n = 35 vs. 32.7%, n = 17), respectively. The German shepherd’s breed showed a high prevalence of TVT compared to other breeds. There was a positive association between sex and outcomes. Most occurrences of regret in Group II were reported in females (n = 16, 61.5%) compared to male dogs (n = 10, 38.5%). There was also a positive association between breed and outcome. Most occurrences of regret in Group II were reported in German shepherd dogs (n = 16) compared to Group I (n = 7). In Group I, 15 dogs (57.7%) showed a complete regression, and 11 (42.3%) underwent recurrence. However, in Group II, 21 dogs (80.7%) showed a complete regression, and 5 dogs (19.2 %) underwent recurrence. Conclusions: It appears therefore that the simultaneous use of surgery and administration of a single dose of vincristine sulfate could be considered a combination therapy for TVT as it reduces the risk of recurrence and has a reasonable cost. Recognizing potential risk factors associated with TVT in dogs may be helpful in constructing the best preventive measures.

Isolated Microsporum Canis from a canine nasal cavity bearer of intranasal foreign body and Transmissible Venereal Tumor - Radiografic imaging and rinoscopy - case report

Isolated Microsporum Canis from a canine nasal cavity bearer of intranasal foreign body and Transmissible Venereal Tumor - Radiografic imaging and rinoscopy - case report