Squamous Cell Carcinoma In Cats Research Articles

Pinnal Squamous Cell Carcinoma in Cats: A Report of 4 Cases

Pinnal Squamous Cell Carcinoma in Cats: A Report of 4 Cases

Environmental risk factors for the development of oral squamous cell carcinoma in cats.

BackgroundRisk factors for oral squamous cell carcinoma (OSCC) in cats are derived from a single study dated almost 20 years ago. The relationship between inflammation of oral tissues and OSCC is still unclear.ObjectivesTo investigate previously proposed and novel potential risk factors for OSCC development, including oral inflammatory diseases.AnimalsHundred cats with OSCC, 70 cats with chronic gingivostomatitis (CGS), 63 cats with periodontal disease (PD), and 500 controls.MethodsProspective, observational case‐control study. Cats with OSCC were compared with an age‐matched control sample of client‐owned cats and cats with CGS or PD. Owners of cats completed an anonymous questionnaire including demographic, environmental and lifestyle information.ResultsOn multivariable logistic regression, covariates significantly associated with an increased risk of OSCC were rural environment (OR: 1.77; 95% CI: 1.03‐3.04; P = .04), outdoor access (OR: 1.68; 95% CI: 1.07‐2.63; P = .02), environmental tobacco smoke (OR: 1.77; 95% CI: 1.05‐3; P = .03), and petfood containing chemical additives (OR: 1.98; 95% CI: 1.04‐3.76; P = .04). Risk factors shared with CGS and PD were outdoor access and petfood containing chemical additives, respectively. A history of oral inflammation was reported in 35% of cats with OSCC but did not emerge as a risk factor.Conclusions and Clinical ImportanceThe study proposes novel potential risk factors for OSCC in cats. Although a history of inflammatory oral disease was not significantly more frequent compared with random age‐matched controls, OSCC shared several risk factors with CGS and PD.

Esophageal Squamous Cell Carcinoma in Cats

Background: Esophageal neoplasms are rarely reported in cats. The frequency rate is less than 0.5% and those neoplasms are usually malignant. Esophageal squamous cell carcinoma (SCC) is an idiopathic epithelial neoplasm, invasive and metastatic that can induce partial or complete obstruction of the esophageal lumen. There is no breed or sex predisposition, and it is more common in cats over 8-years-old. Esophageal SCC is more frequent in the middle third of the esophagus. The prognosis is poor, as the cats are usually diagnosed at an advanced stage. This report aims to describe clinical, endoscopic, radiographic, and pathological features of two cases of esophageal squamous cell carcinoma in cats.Cases: A 11-year-old neutered male cat presenting regurgitation, weight loss, anorexia and dyspnea was referred to veterinary internal medicine care. Simple and contrast-enhanced radiographic images of the cervical and thoracic regions showed an alveolar pattern in the cranial lung lobes and signs of esophageal lumen irregularity and dilatation in the mediastinum topography. The upper digestive endoscopy showed a dilated esophageal lumen, and an irregular mass was observed in the thoracic esophagus involving the entire esophageal circumference. Biopsy fragments were collected, and the histopathological result was compatible with squamous cell carcinoma. The second case was a 10-year-old neutered male cat presenting hyporexia, regurgitation, dyspnea, tachypnea, and abnormal breath sounds. The ultrasound of the chest showed 3 amorphous hypoechogenic and heterogeneous areas in the right and left hemithorax between parietal and visceral pleura. The cytological examination was compatible with a malignant epithelial tumor. The patient died 3 months after the onset of clinical signs. At gross exam, it was observed a friable, irregular, and ulcerated mass of 5.0 x 3.0 cm in the middle third of the esophagus. Metastatic foci in the lungs and liver were also observed. The histopathological diagnosis was esophageal squamous cell carcinoma, with metastases to liver and lungs. Microscopically, in both cases, were seen aproliferation of polyhedral epithelial cells in the mucosa, arranged in nests or trabeculae with central keratinization. These cells presented oval to rounded nuclei, loose chromatin, prominent nucleolus, and abundant eosinophilic cytoplasm, with marked anisocytosis and anisokaryosis, supported by a thin fibrovascular stroma. In the second cat the neoplastic cells infiltrated the esophageal submucosa, including lymphatic vessels and muscle layer. Lung and liver metastases from theSCC had a cellular pattern similar to the primary neoplasm.Discussion: Esophageal squamous cell carcinoma is extremely rare in cats. The SCC begins in the squamous layer of the mucosa and can infiltrate the muscular layer or protrude into the esophageal lumen, leading to clinical signs, as seen in these 2 cats. The differential diagnoses for esophageal SCC include foreign bodies, esophageal strictures, and infiltrative or compressive non-esophageal tumors. Although uncommon, esophageal tumors should be considered when evaluatingelderly cats with regurgitation and weight loss. The diagnosis of esophageal SCC was confirmed by histopathological findings collected endoscopically or during necropsy. As noted in both cases, the prognosis of SCC is generally unfavorable, usually due to the difficulty in treatment and diagnosis in a late stage of the disease.Keywords: feline, esophagus, neoplasms, metastasis, cancer.

Do papillomaviruses cause feline cutaneous squamous cell carcinoma?

PICO question
 In cats infected with papillomavirus, is the risk of developing feline cutaneous squamous cell carcinoma greater than cats that are not infected with papillomavirus?
 
 Clinical bottom line
 Category of research question
 Risk
 The number and type of study designs reviewed
 Eleven papers were critically reviewed, nine were case-control studies and two were experimental in vitro studies
 Strength of evidence
 Moderate
 Outcomes reported
 Infection of feline epithelial skin cells with Felis catus papillomavirus type 2 (FcaPV-2) is a risk factor for the development of feline cutaneous squamous cell carcinoma. The pathogenesis of FcaPV-2 infection and neoplastic transformation into malignant cells shares similar pathways to the human papillomavirus (HPV) model of pathogenesis and carcinogenesis with some differences
 Conclusion
 In conclusion, there is moderate strength of evidence in the literature to support a role of FcaPV-2 in the development of cutaneous squamous cell carcinomas in cats. Therefore, prevention of infection with FcaPV-2 should prevent some cancers
 
 How to apply this evidence in practice
 The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources.
 Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.
 

Persistent activation of the mammalian target of rapamycin signalling pathway in cutaneous squamous cell carcinomas in cats.

Cutaneous squamous cell carcinoma (CSCC) represents the most common malignant tumour of the feline skin. Emerging evidence suggests that the phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signalling pathway may represent a potential target for pharmacological intervention in human and canine CSCC. The present study aimed to explore the expression pattern and status of activation of relevant signalling proteins of the PI3K/Akt/mTOR signalling pathway in feline CSCC. The expression of pEGFRTyr1068 , pAktSer473 , pS6Ser235/236 combined with Ki-67, and the tumour suppressor protein PTEN was evaluated by immunohistochemical analysis in 45 samples of feline CSCC, using a tissue microarray. The immunodetection using phosphospecific antibodies to detect the activated forms of signalling proteins showed that the PI3K/Akt/mTOR signalling pathway is frequently activated in feline CSCCs, and may be independent of the activation of EGFR. The results also showed that PTEN expression is not significantly altered in feline CSCCs. Our study shows that the persistent activation of the PI3K/Akt/mTOR signalling pathway represents a key event in feline CSCC, pointing to this signalling pathway being a potential therapeutic target in feline patients with CSCC.

Cutaneous Spindle Cell Squamous Cell Carcinoma in Cats: Clinical, Histological, and Immunohistochemical Study.

This study describes the clinical and pathological characteristics of cutaneous spindle cell squamous cell carcinoma (SCSCC) in 18 cats. The average age of the cats was 11.8 ± 2.7 years, and all tumors were located in the facial skin, mainly affecting the pinna (13/18, 72%), followed by the periorbital area (4/18, 22%) and the dorsal muzzle (1/18, 6%). Tumors were composed of fusiform neoplastic cells with moderate atypia arranged in solid sheets or fascicles with foci of squamous differentiation. A panel of antibodies against cytokeratins, vimentin, S-100 protein, NSE, GFAP, Melan A, SMA, desmin, CD18, CD31, and p63 was used to help differentiate SCSCC from other spindle cell malignancies. SCSCCs expressed CK5/6 (17/18, 94%), AE1/AE3 (15/18, 83%), and p63 protein (18/18, 100%), but there was no immunolabeling for CK8/18. A role for sunlight exposure in the pathogenesis of the tumors was suggested by changes indicative of actinic keratosis, the location of the tumors in dorsal areas, and the absence of histomorphologic features of papillomavirus infection. Recurrence was not recorded in 14/18 cases (78%) during a follow-up period of 7 to 25 months. Three of 18 (17%) tumors recurred or led to humane euthanasia due to local progression, and one case (5%) had regional lymph node metastasis. Clinical outcome varied with cutaneous location, mitotic count, and invasion of surgical margins; thus, SCSCCs with a more aggressive behavior were located in the periorbital area (4/4 cases), had ≥14 mitoses in 10 high-power fields (2.37 mm2) (4/4 cases), and showed invasion of surgical margins (3/4 cases).

Detection of Epithelial Cell Adhesion Molecule in Feline Normal and Tumor Cell Lines and Tissues With Selected Commercial Anti-human EpCAM Antibodies.

Epithelial cell adhesion molecule (EpCAM) is a transmembrane protein expressed at intercellular junctions in epithelial cells. As an epithelial biomarker, it used for immunologic-based capture of epithelial-derived circulating tumor cells (CTCs) in human patients with different carcinomas. EpCAM expression has not been described in normal or neoplastic epithelial tissues in cats. Our goal was to find a commercial antibody that recognizes surface EpCAM expression for CTC detection. We tested two anti-human EpCAM antibodies, designated for use with flow cytometry, for detection of surface EpCAM expression on feline cell lines derived from normal mammary and renal epithelia and mammary and oropharyngeal squamous cell carcinomas in cats. Only one of the antibodies, a goat polyclonal antibody, labeled normal and neoplastic feline mammary epithelial cells and oropharyngeal squamous cell carcinoma cells; no labeling was observed for normal feline kidney epithelial cells. At low dilution, this antibody immunohistochemically stained the intercellular junctions of normal pancreatic, intestinal and mammary epithelium, as well as neoplastic mammary epithelium in feline tissues; however, oral mucosa, skin, and an oropharyngeal squamous cell carcinoma showed no positive immunostaining. The antibody only weakly bound feline squamous cell carcinoma cell lines under static adhesion. Our results indicate that EpCAM is expressed in specific epithelia in cats but is variably expressed in feline mammary tumors and oropharyngeal squamous cell carcinoma. A higher avidity cross-reactive or feline-specific antibody will be required to further investigate EpCAM expression in normal and neoplastic feline tissue or for detecting CTCs in the blood of tumor-bearing cats.

Comparison of prevalence of Felis catus papillomavirus type 2 in squamous cell carcinomas in cats between Taiwan and Japan.

Felis catus papillomavirus (FcaPV), especially type 2 (FcaPV2) is considered as one of the causative agents in squamous cell carcinoma (SCC) in cats. However, our previous study detected FcaPV3 and FcaPV4, but not FcaPV2 in feline SCCs collected in Japan, suggesting that the prevalence of FcaPV2 in SCC may vary depending on geographic locations. To evaluate this hypothesis, two conventional PCR reactions targeting E1 and E7 genes were performed to detect FcaPV2 in feline SCC samples collected in Taiwan and Japan. While 46.9% (23/49) of feline SCC cases from Taiwan were PCR positive for FcaPV2, only 8.6% (3/35) cases from Japan were positive. Our result suggests that the prevalence of FcaPV2 in feline SCCs may depend on the region.

Canine and Feline Oral Cavity Tumours and Tumour-like Lesions: a Retrospective Study of 486 Cases (2015–2017)

Oral cavity tumours and tumour-like lesions are common in dogs and cats, and their diagnosis and classification requires histopathological examination. The aim of this study was to analyse retrospectively oral cavity lesions in dogs and cats in order to evaluate the distribution of inflammatory, hyperplastic and neoplastic lesions manifested as tumours. A total of 486 oral cavity tumours and tumour-like lesions (340 canine; 146 feline), diagnosed routinely from 2015 to 2017, were included. The lesions were classified as inflammatory, hyperplastic or neoplastic (benign and malignant). Histopathological diagnosis was based on haematoxylin and eosin staining and, when necessary, May-Grünwald-Giemsa (for mast cell tumours) or Masson's Fontana (for melanomas) stains or immunohistochemistry (for CD3, CD79α and S100 markers). For dogs, 29.11% (99/340) of the lesions were benign tumours, 24.12% (82/340) were hyperplastic lesions and 14.7% (50/340) were inflammatory lesions. For cats, 4.79% (7/146) were benign tumours, 15.07% (22/146) were hyperplastic lesions and 57.53% (84/146) were inflammatory lesions. Furthermore, 23.24% (79/340) of canine cases were diagnosed with gingival hyperplasia and 19.12% (65/340) were diagnosed with peripheral odontogenic fibroma, while 43.84% (64/146) of feline cases were diagnosed with chronic lymphoplasmacytic stomatitis. Malignant tumours in dogs and cats constituted 32.06% (109/340) and 21.91% (32/146) of the lesions, respectively, with high-grade melanoma in dogs and squamous cell carcinoma in cats being the most common.

Carcinoma escamoso oral em gato jovem

Background: : : Oral neoplasms are common in cats. Just the percentage of oral squamous cell carcinoma (SCC) accounts for about 70% of all feline oral tumors also it is considered highly invasive and malignant. There are reports that the flea collar increases five times the risk oral SCC development. In addition, smoke exposure is also considered a risk factor, and the animals were exposed to tobacco when makes it self-cleaning. SCC well differentiated is characterized histologically by numerous keratin pearls formation and clearly evident intercellular bridges with poor mitotic activity and nuclear pleomorphism. The median age of cats with oral SCC is about 11-13 years, but, cats as young as three years and as old as twenty-one years have been previously reported. However, it was not found reports of oral SCC in cats at age younger than one year old. The aim of this article is reports one case of oral SCC feline at age of three months old. Five days after surgical procedure the patient returned to the veterinary and the owner report that it returned to eating well. Case: It was exanimate a three months old male mixed breed cat presenting oral volume increased and the biopsy test was suggested. However, the owner returned 3 months later when the animal showed tumor 6 cm in diameter, dysphagia, tongue protrusion, excessive salivation, halitosis and weight loss. It was indicated a wide surgical excision of tumoral mass. The tissue was submitted to histopathology. Discussion: The historical, macroscopic characteristics and predisponents factors may aid in carcinoma diagnosis, however, the cytologic or histological examination of tissue confirms this diagnosis. Therefore, the microscopic evaluation revealed a malignant neoplastic proliferation of stratified squamous epithelial cells desmosomal junctions evident, few foci keratin pearl formation and presence of mononuclear inflammatory reaction perifocal. A well-differentiated squamous cell carcinoma was diagnosed by histological study. Thirty days after the surgical procedure, the animal showed a complete recovery with weight increase and eating normally. Thus, surgery proves to provide excellent quality of life maintenance for a long period of time and, although it had shown no signs of recurrence at the present moment, the literature describes that SCC long-term recurrences are common. Indeed, an important question is the quality of life of the felines with oral SCC, whereas this neoplasm led to a marked decrease in eating and drinking due to pain. Therefore, the treatment target is making the possible to maintain an excellent quality of life as long as possible. With the surgery was possible the maintenance of an excellent quality of life for a longer period. An early diagnosis could have defined the need for surgical procedure before the animal presented clinical signs characteristic, whereas represent a locally invasive neoplasm with poor response to conventional treatments models and unfavorable prognosis. Actually, increased incidences of SCC have been associated with clinical and preventive veterinary medicine improvements, which led to the prolongation of life to this animal, becoming more susceptible to senile disease, but this paper reports one case of oral SCC feline at age of three months old.

Response, disease-free interval and overall survival of cats with nasal planum squamous cell carcinoma treated with a fractionated vs a single-dose protocol of strontium plesiotherapy.

The main aim of the study was to establish response, disease-free interval (DFI) and overall survival of cats with nasal planum squamous cell carcinoma (SCC) treated with Sr90 plesiotherapy. A secondary aim was to determine whether a fractionated protocol is more effective than a single-dose protocol in terms of response, DFI and overall survival. The third aim was to evaluate whether we can identify prognostic factors that influence overall survival. This was a retrospective study that included cats with a diagnosis of nasal planum SCC treated with Sr90 plesiotherapy at a single institution. Seventy-four cats were included in the study. Thirty-two were treated with a fractionated protocol and 42 with a single-dose treatment. Sr90 plesiotherapy was able to induce complete response in 74% of cats with nasal planum SCC. The median DFI was 780 days (95% confidence interval [CI] 383-1177), with 17% of cats experiencing local recurrence. The overall survival for all cats was 1039 days (95% CI 55-1528). The DFI of cats treated with the fractionated Sr90 was significantly longer compared with the single-dose treatment, whereas response and overall survival were not statistically different. Other prognostic factors that influenced the overall survival were early-stage disease, absence of concurrent problems and complete response to the treatment. Acute and long-term toxicity associated with the treatment were minimal and the aesthetic outcome was pleasing in almost all cases. Strontium plesiotherapy is a safe and effective treatment of nasal planum SCC in cats.

Squamous cell carcinoma in cat − differential diagnosis and multimodal therapeutic approach

Squamous cell carcinoma in cat − differential diagnosis and multimodal therapeutic approach

Evaluation of the cryosurgery for treatment of squamous cell carcinoma in cats

ABSTRACT The cryosurgery is a very useful therapy for the treatment of a variety of neoplastic and non-neoplastic processes. Nevertheless, it is still poorly described as an option for the treatment of specific cutaneous neoplasms, such as squamous cell carcinoma. The purpose of the present study was to analyze the clinical response of cryosurgery for the treatment of squamous cell carcinoma in cats. For this 13 squamous cell carcinoma lesions were selected in 11 cats, diagnosed through citopathological and/or histopathological examinations. The lesions were frozen using liquid nitrogen spray, and the evaluations were performed in the moment of freeze and approximately every 15 days until the wound was completely healed. The response of cryosurgery was considered complete with tumoral remission on 38.5% of the cats, and partial on 46.1%. The main complications included crusting and nostril stenosis. The presented results suggested that cryosurgery is effective and may be a viable option for the treatment of squamous cell carcinoma in cats. The effectiveness of the therapy; however, depends on the correct selection of the candidates for cryosurgery based on the lesion size, and the attendance to some criteria, such as the freezing time and post-operative care.

Intratumoral injection of radioactive holmium ( 166 Ho) microspheres for treatment of oral squamous cell carcinoma in cats.

A "microbrachytherapy" was developed as treatment option for inoperable tumours by direct intratumoral injection of radioactive holmium-166 ( 166 Ho) microspheres (MS). 166 Ho emits β-radiation which potentially enables a high, ablative, radioactive-absorbed dose on the tumour tissue while sparing surrounding tissues. Safety and efficacy of 166 Ho microbrachytherapy were evaluated in a prospective cohort study of 13 cats with inoperable oral squamous cell carcinoma without evidence of distant metastasis. Local response rate was 55%, including complete response or partial response (downstaging) enabling subsequent marginal resection. Median survival time was 113 days overall, and 296 days for patients with local response. Side effects were minimal. Tumour volume was a significant predictor of response. Response rate may be further improved by optimizing the intratumoral spatial distribution of 166 Ho MS. 166 Ho microbrachytherapy has potential as a minimally invasive, single procedure radio-ablation treatment of unresectable tumours with minimal morbidity.

Neoplasmas oculares e de anexos em cães e gatos no Rio Grande do Sul: 265 casos (2009 -2014)

Neoplasias oculares causam desconforto, problemas de visão e podem refletir doenças sistêmicas. Um estudo retrospectivo foi realizado para identificar e analisar neoplasmas oculares e de anexos obtidos por biópsias enviadas ao Setor de Patologia Veterinária (SPV) da Universidade Federal do Rio Grande do Sul (UFRGS). Durante o período de janeiro de 2009 a dezembro de 2014 realizou-se 265 diagnósticos de neoplasmas oculares e de anexos, destes 87,5% na espécie canina e em 12,5% na espécie felina. As neoplasias ocorreram mais em animais com idade superior a 12 meses e idosos, e os cães (52/232) e gatos (21/33) sem raça definida foram os mais acometidos. A pálpebra foi o local mais acometido na espécie canina (164/232) e felina (20/33), seguida pela terceira pálpebra em cães (20/232) e órbita nos felinos (5/33). O tumor mais diagnosticado nos cães foi o adenoma meibomiano (82/232) e nos gatos o carcinoma de células escamosas (10/33), ambos em pálpebras. Foram identificados nos cães 24 tipos tumorais e nos gatos 16. Em caninos as neoplasias benignas representaram o maior número de diagnósticos (56%) sendo que em felinos o maior número de casos foi de neoplasias malignas (75,8%).

A survey of veterinary radiation facilities in 2010.

A survey of veterinary radiation therapy facilities in the United States, Canada, and Europe was done in 2010, using an online survey tool, to determine the type of equipment available, radiation protocols used, caseload, tumor types irradiated, as well as other details of the practice of veterinary radiation oncology. The results of this survey were compared to a similar survey performed in 2001. A total of 76 facilities were identified including 24 (32%) academic institutions and 52 (68%) private practice external beam radiation therapy facilities. The overall response rate was 51% (39/76 responded). Based on this survey, there is substantial variation among facilities in all aspects ranging from equipment and personnel to radiation protocols and caseloads. American College of Veterinary Radiology boarded radiation oncologists direct 90% of the radiation facilities, which was increased slightly compared to 2001. All facilities surveyed in 2010 had a linear accelerator. More facilities reported having electron capability (79%) compared to the 2001 survey. Eight facilities had a radiation oncology resident, and academic facilities were more likely to have residents. Patient caseload information was available from 28 sites (37% of radiation facilities), and based on the responses 1376 dogs and 352 cats were irradiated in 2010. The most frequently irradiated tumors were soft tissue sarcomas in dogs, and oral squamous cell carcinoma in cats.

Electrochemotherapy with intravenous bleomycin injection: an observational study in superficial squamous cell carcinoma in cats

The aim of this study was to evaluate the efficacy and safety of electrochemotherapy (ECT) with bleomycin for treatment of squamous cell carcinoma (SCC) in cats. Between March 2008 and October 2011, 11 cats with 17 superficial SCC nodules in different clinical stages (ranging from Tis to T4), located on nasal planum (6/11), pinnae (3/11) and both locations (2/11), were included in a prospective non-randomised study. Sixteen of 17 SCC nodules were treated with ECT (15/16 with single session and in one case with two sessions); one nodule was surgically removed. Altogether, complete response (CR) was achieved for 81.8% (9/11) cats and 87.5% (14/16) nodules, lasting from 2 months up to longer than 3 years. Only 2/9 cats in which CR was initially observed, had recurrence 2 and 8 months after the ECT procedure. In the remaining two cats with highly infiltrative spread into adjacent tissues, progression of the disease was observed, despite ECT, and both were euthanased 4 and 5 months after the procedure. ECT in cats was well tolerated and no evident local or systemic side effects were observed. The results of this study suggest that ECT is a highly effective and safe method of local tumour control of feline cutaneous SCCs. It should be considered as an alternative treatment option, especially when other treatment approaches are not acceptable by the owners, owing to their invasiveness, mutilation or high cost.

Pinnal squamous cell carcinoma in cats and the effectiveness of treatment with radical pinnectomy

  The aim of this study was to observe the effectiveness of treatment with radical pinnectomy and investigate postoperative relapse cases in pinnal squamous cell carcinoma in cats. Twelve cats which were brought to surgery clinic of Istanbul University, Faculty of Veterinary Medicine were used. Biopsies were taken from the cases in which squamous cell carcinoma was suspected following anamnesis and the clinical examination of patients that were brought to our clinic. The patients were diagnosed on the basis of histopathological analysis of biopsy samples. Haemogram and biochemical blood analysis were performed and thoracic radiographs were taken as routine in cases that a decision was made to operate. After the area was prepared for operation radical pinnectomy or total external acoustic canal ablation along with radical pinnectomy were performed in the patients that were eligible for operation. Relapses seen in the postoperative period were re-operated with the techniques selected according to invasion status. Periodic controls of the patients were made after the operations and the cats were examined for relapse. In seven out of 12 cases, only squamous cell carcinoma; in three cases, actinic dermatitis actinic dermatitis in addition to squamous cell carcinoma, and in two cases, only actinic dermatitis lesions were detected. In the postoperative period, relapse was observed in the cases in which the squamous cell carcinoma lesion reached the lower half of the pinna or the external acoustic canal while relapse was not observed in cases with actinic dermatitis lesions or when the squamous cell carcinoma lesion was on the top part of the pinna. Relapse cases were re-operated using different operative techniques. It is concluded that performing radical pinnectomy on actinic dermatitis lesions detected on the pinna before development into squamous cell carcinoma, and removing the tumour according to its localization with radical pinnectomy or total external acoustic canal ablation alongside radical pinnectomy is the most reliable treatment option in terms of relapse in cases of pinnal squamous cell carcinoma.  

Transcoelomic spread and metastasis of a squamous cell carcinoma of presumed pancreatic duct origin in a cat

CASE HISTORY: A 13-year-old female spayed domestic shorthaired cat was examined because of lethargy, inappetance and weight loss. CLINICAL FINDINGS: No clinically significant haematological or biochemical abnormalities were detected, but an abdominal mass was palpated. Abdominal examination using ultrasonography revealed soft tissue masses in the cranial abdomen, involving the spleen, as well as the liver and abdominal wall; the pancreas was not identified. Despite supportive therapy the condition of the cat rapidly deteriorated and euthanasia was performed. PATHOLOGICAL FINDINGS: Cytological preparations from the cranial abdominal mass revealed a population of pleomorphic epithelial cells consistent with a squamous cell carcinoma. On post-mortem examination, firm creamy white to yellow nodular masses were present in the region of the pancreatic left limb, spleen, liver, diaphragm, right abdominal wall and in the left lung. Sections of all masses were examined histopathologically and demonstrated infiltration by neoplastic epithelial cells indicative of squamous cell carcinoma (SCC). DIAGNOSIS: Squamous cell carcinoma of presumed pancreatic duct origin. CLINICAL RELEVANCE: There are few reports of haematogenous or lymphatic metastasis of SCC in cats, and none reporting transcoelomic spread. This report describes the clinical and pathological features of a case of presumed primary pancreatic ductal SCC, and should alert veterinarians to the potential for metastasis and carcinomatosis.

5-lipoxygenase expression and tepoxalin-induced cell death in squamous cell carcinomas in cats.

To assess expression pattern and subcellular compartmentalization of 5-lipoxygenase in cutaneous, UV radiation-induced, and oral squamous cell carcinomas (SCCs) in cats and determine the effects of cyclooxygenase or 5-lipoxygenase inhibition on proliferation or apoptosis in a feline oral squamous cell carcinoma (SCCF1) cell line. 60 archived paraffin-embedded samples of SCCs from 60 cats and SCCF1 cells. Retrospective immunohistochemical analysis of the archived samples of SCCs (20 cutaneous, 20 UV radiation-induced, and 20 oral tumors) was performed. Cell culture proliferation assays involving SCCF1 cells were performed, and tepoxalin-induced apoptosis and signaling were examined via western blotting and annexin V staining. Immunohistochemically, staining for 5-lipoxygenase was most frequently of greatest intensity in oral SCCs, whereas staining of cutaneous and UV radiation-induced lesions had less consistent 5-lipoxygenase expression. Exposure of SCCF1 cells to the 5-lipoxygenase inhibitor tepoxalin resulted in apoptosis; the effect appeared to be mediated via alteration of cell signaling rather than via suppression of lipid mediators that are typically produced as a result of 5-lipoxygenase activity. In cats, expression of 5-lipoxygenase in SCCs appeared to differ depending on tumor location. The influence of tepoxalin-induced 5-lipoxygenase inhibition on a 5-lipoxygenase-expressing cell line coupled with the notable expression of 5-lipoxygenase in oral SCCs suggested that 5-lipoxygenase inhibition may have therapeutic benefits in affected cats. Although the safety of tepoxalin in cats has yet to be investigated, 5-lipoxygenase inhibitors should be evaluated for use as a potential treatment for SCCs in that species.