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1.
Vet Clin Pathol ; 53(1): 131-135, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418393

RESUMO

Cutaneous mast cell tumors are rarely reported in cattle. Although mutations in the c-KIT gene have been shown to play a central role in the oncogenesis of canine mast cell tumors, few data are available in cattle. This report describes the clinical, histologic, immunohistochemical, and genetic features of a multicentric cutaneous mast cell tumor in an adult cow. An 11-year-old Prim'Holstein cow was presented for a 5-month history of multiple skin nodules. Cytologic and histologic analyses of the nodules led to a diagnosis of mast cell tumors. Immunohistochemical analysis for KIT expression showed a moderate to strong signal in neoplastic mast cells with a cytoplasmic and membranous pattern. Sequencing of the c-KIT gene coding sequence revealed no mutation. Despite partial response after corticosteroid treatment, euthanasia was elected. No metastases to the lymph nodes, spleen, and liver were identified at post-mortem and histologic examinations.


Assuntos
Doenças dos Bovinos , Doenças do Cão , Mastocitoma Cutâneo , Neoplasias Cutâneas , Feminino , Bovinos , Animais , Cães , Mastócitos/patologia , Doenças do Cão/diagnóstico , Neoplasias Cutâneas/veterinária , Mastocitoma Cutâneo/patologia , Mastocitoma Cutâneo/veterinária , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Doenças dos Bovinos/patologia
2.
Vet Comp Oncol ; 21(3): 401-405, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37186079

RESUMO

Mast cell tumour (MCT) is one of the most frequent skin tumours in dogs. Due to their unpredictable biological behaviour, MCTs often cause several therapeutic frustrations, leading to investigation regarding prognostic markers. Lysyl oxidase (LOX) is an enzyme that promotes extracellular matrix stability and contributes to cell migration, angiogenesis and epithelial-mesenchymal transition. Its expression positively correlates with poor prognoses in several human and canine mammary cancers. The aim of this study was to characterise the immunohistochemical expression of LOX in MCT samples and compare it with histological grading and post-surgical survival. Twenty-six tumours were submitted to immunohistochemistry for LOX expression evaluation. All samples were positive for LOX, with variable percentages of cytoplasmic and nuclear positivity. Cytoplasmic positivity was significantly higher in high-grade MCTs (P = .0297). Our results indicate that high expression of cytoplasmic LOX in neoplastic mast cells is an indicator of poor prognosis for canine cutaneous MCTs.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Neoplasias Cutâneas , Humanos , Cães , Animais , Mastócitos/patologia , Proteína-Lisina 6-Oxidase , Doenças do Cão/metabolismo , Mastocitoma Cutâneo/veterinária , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/veterinária , Prognóstico
3.
J Am Vet Med Assoc ; 261(9): 1-6, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37116878

RESUMO

OBJECTIVE: To report preliminary findings of hypofractionated superficial radiotherapy for treatment of cutaneous mast cell tumors (MCTs) and report the acute and late toxicity associated with its use. ANIMALS: 3 dogs and 1 cat. PROCEDURES: In this retrospective study, medical records from January 2021 through July 2022 were searched for animals that received superficial radiation therapy for MCTs of the head. RESULTS: 4 patients with 5 MCTs were included. Three of the masses were periocular and required protection of the globe with a tungsten eye shield. One patient did not complete the intended protocol due to diffuse metastatic spread noted after the second fraction. Of the 3 patients that completed their protocol, 100% had a complete response. Two canine patients were treated adjunctively with toceranib. Two of the 4 patients experienced grade 1 acute veterinary radiation therapy oncology group (VRTOG) toxicity, and the 3 patients that completed their protocol experienced grade 1 late VRTOG toxicity. No radiation effects were documented to the cornea or lens in any patient. CLINICAL RELEVANCE: Superficial radiation therapy was effective in our limited study population, and patients experienced minimal side effects for treatment of cutaneous MCTs.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Neoplasias Cutâneas , Cães , Animais , Estudos Retrospectivos , Neoplasias Cutâneas/radioterapia , Neoplasias Cutâneas/veterinária , Neoplasias Cutâneas/patologia , Raios X , Mastócitos/patologia , Mastocitoma Cutâneo/veterinária , Doenças do Cão/tratamento farmacológico , Doenças do Cão/radioterapia , Doenças do Cão/patologia
4.
Vet Comp Oncol ; 21(2): 332-338, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36907653

RESUMO

Canine cutaneous mast cell tumours (cMCTs) of the pinna have been associated with an aggressive biological behaviour, although data remain scarce. The knowledge acquired over the past years on histologic gradings, and the value of lymph node (LN) staging, may help in better characterizing this anatomical presentation. The first aim was to describe the frequency, location, and histologic appearance of LN metastases in cMCT of the pinna. A second aim was to evaluate prognosis. Medical records of dogs with cMCT of the pinna, that underwent tumour and sentinel (SLN) or regional LN (RLN) excision, were reviewed. The influence of potential prognostic variables on time to progression (TTP) and tumour-specific survival (TSS) was investigated. Thirty-nine dogs were included: 19 (48.7%) had Kiupel high-grade (K-HG) and 20 (51.3%) had low-grade (K-LG) MCTs. Eighteen (46.1%) dogs underwent SLN mapping: the superficial cervical LN was at least one of SLN in 17 (94.4%) cases. Twenty-two (56.4%) dogs had LN metastases; the superficial cervical LN was always involved. On multivariable analysis, only K-HG was associated with increased risk of progression (p = .043) and tumour-related death (p = .021). Median TTP and TSS were 270 and 370 days in K-HG, respectively; these were not reached in dogs with K-LG tumours (p < .01). cMCTs of the pinna are often K-HG and are also associated with a higher frequency of LN metastasis; however, we confirmed the independent prognostic value of histologic grading. A multimodal treatment may lead to favourable long-term outcome. Moreover, the superficial cervical LN is most often the SLN.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Cães , Animais , Estudos Retrospectivos , Doenças do Cão/patologia , Prognóstico , Mastocitoma Cutâneo/veterinária , Metástase Linfática
7.
J Comp Pathol ; 193: 1-8, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35487618

RESUMO

Cell proliferation is a fundamental criterion in the assessment of malignant progression of many tumours and an essential parameter in several grading schemes. However, proliferation may be dependent on patient age and other variables, as shown in normal tissues, cultured cells and human neoplasms. We thus hypothesized that age or other patient or tumour-related parameters might generally affect proliferation in canine neoplasms, which might be of value for optimizing prognostic algorithms. We performed linear regression analyses to associate age, sex and tumour size with digitally quantified immunohistochemical Ki67 labelling indices (Ki67-LIs) of 495 canine tumours, including cutaneous mast cell tumours (MCTs, n = 70), soft tissue sarcomas (n = 61), plasmacytomas (n = 86), trichoblastomas (n = 62) and perianal gland adenomas (PGAs, n = 95) as well as testicular interstitial (n = 65) and Sertoli cell tumours (n = 56). In MCTs, the Ki67-LI increased 1.13-fold per year of age (P <0.05) in bitches but not in males. Conversely, in PGAs it rose 1.10-fold per year in males (P <0.05) while it decreased 0.95-fold in bitches (P = 0.37). Only in MCTs and PGAs was the Ki67-LI associated with tumour size, albeit in oppositional directions (MCTs: 1.26-fold per cm diameter, P <0.01; PGAs: 0.76-fold, P <0.01). No correlations were found in the other tumour types. The few sex-dependent correlations with patient age and tumour size established here indicate highly tumour-type specific mechanisms, but the diagnostic consequences are uncertain.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Tumor de Células de Sertoli , Neoplasias Testiculares , Animais , Doenças do Cão/patologia , Cães , Humanos , Antígeno Ki-67/metabolismo , Masculino , Mastocitoma Cutâneo/veterinária , Tumor de Células de Sertoli/veterinária , Neoplasias Testiculares/patologia , Neoplasias Testiculares/veterinária
8.
Vet Clin Pathol ; 51(3): 339-348, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35419864

RESUMO

BACKGROUND: Fibroblasts and/or collagen fibrils have not been included in previous cytologic grading schemes of canine mast cell tumors (MCTs), and their association with biological behavior is broadly debated. OBJECTIVES: This study aimed to evaluate the cytologic findings of canine MCT, with emphasis on the microenvironment, and propose a novel cytologic grading system correlated with mortality and histologic grade. MATERIAL AND METHODS: Cytology smears of canine cutaneous MCTs were retrospectively reviewed and compared with their histopathologic counterparts using Cohen´s Kappa test. One-year survival rates were also compared with the cytologic and histopathologic variables using Pearson´s correlation test. RESULTS: From 92 first-occurrence canine cutaneous MCTs, the five features most associated with mortality were selected for a new grading system. The five features were cytoplasmic granulation, fibroblast and/or collagen fibril concentrations, and the presence of mitotic figures, multinucleation, and karyomegaly. Among concordant histopathologic and cytologic cases (ie, the same grades using both systems), mortality rates were 2.6% (1/38) for low-grade and 71.4% (10/14) for high-grade cases (P < 0.001, chi-square). For false-negative and false-positive results, mortality rates were 33% (1/3) and 45% (5/11), respectively (P = 0.707). CONCLUSIONS: Unlike the Camus cytologic grading system, the present amendment excluded binucleation and included fibroblasts and/ or collagen fibrils, which in higher concentrations were associated with increased survival and a low histopathologic grade. Cytologic grading with the inclusion of fibroblast and collagen fibril concentrations correlated with survival, as did the Camus cytologic and Kiupel histopathologic grades; however, further studies are needed to confirm the prognostic value of this novel cytologic grading scheme.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Neoplasias Cutâneas , Animais , Colágeno , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Fibroblastos/patologia , Mastócitos/patologia , Mastocitoma Cutâneo/patologia , Mastocitoma Cutâneo/veterinária , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/veterinária , Microambiente Tumoral
9.
Vet Comp Oncol ; 20(3): 551-558, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35195937

RESUMO

In canine cutaneous mast cell tumours (cMCTs), histologic grade and clinical stage are the most important prognostic factors, with high-grade tumours and metastatic lymph nodes (LNs) significantly influencing the evolution of disease. However, it is uncertain whether histologic grade and clinical stage should be given equal weighting value in patient prognostication and management. Dogs with low- and high-grade cMCTs and at least one overtly metastatic sentinel LN undergoing standardized treatment, consisting of surgical excision of the cMCT, lymphadenectomy and chemotherapy, were retrospectively included. The aim was to determine whether, at the same clinical stage, histologic grade retained prognostic relevance. Sixty dogs were included: 26 had a high-grade cMCT tumour and 34 had a low-grade cMCT. Median follow-up was 367 days (range, 187-748) in the high-grade group, and 1208 days (range, 180-2576) in the low-grade group. Median time to progression was significantly shorter in the high-grade group than in the low-grade group (214 days versus not reached; p < .001), as well as tumour-specific survival (545 days versus not reached; p < .001). On multivariable analysis, a high histologic grade and incomplete margins retained prognostic significance for both tumour progression and tumour-specific death. In dogs with cMCT and at least one overtly metastatic LN undergoing multimodal treatment, histologic grade significantly correlated with outcome. Overall prognosis was not unfavourable, even in the high-grade group, further supporting that a multimodal therapeutic approach, addressing primary tumour and sentinel LN, should be offered. Whether chemotherapy should be incorporated in the therapeutic planning of low-grade cMCTs remains to be defined.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Linfonodo Sentinela , Animais , Doenças do Cão/patologia , Cães , Linfonodos/patologia , Metástase Linfática , Mastócitos/patologia , Mastocitoma Cutâneo/veterinária , Estudos Retrospectivos , Linfonodo Sentinela/patologia
10.
J Vet Diagn Invest ; 34(3): 523-527, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35191338

RESUMO

Better understanding of mast cell tumors (MCTs) in miniature pigs is needed to guide diagnosis and establish clinical significance. We characterized the gross pathology, histopathology, histochemical staining, and KIT immunoreactivity of cutaneous MCTs in a retrospective descriptive study of 11 miniature pigs (Sus scrofa domesticus). Tumors were single or multiple papules, small nodules, or plaques. In one pig, lymph nodes and internal organs were affected. Histologically, all MCTs involved the dermis, and some extended to the subcutis (4 of 11) and skeletal muscle (1 of 11). Most tumors were well-demarcated, unencapsulated, nodular or multinodular masses (8 of 11) and fewer were poorly demarcated plaques (3 of 11). Neoplastic cells were often well-differentiated with pale amphophilic-to-eosinophilic faintly granular cytoplasm, occasional binucleation, rare multinucleation, and a low mitotic count (<7 per 10 hpf; 10 of 11). Eosinophils were present in tumors in all cases. Cytoplasmic granules stained most consistently with high-pH (2.5-3) toluidine blue (9 of 10) compared to low-pH (0.5-1) toluidine blue (6 of 9) or Giemsa (7 of 10). KIT immunoreactivity patterns were strong perimembranous (4 of 8), focal perinuclear and stippled cytoplasmic (1 of 8), and diffuse cytoplasmic (3 of 8), and included 1 case that was negative for histochemical stains; hence, KIT is a promising diagnostic marker for MCTs in miniature pigs.


Assuntos
Mastocitoma Cutâneo , Neoplasias Cutâneas , Doenças dos Suínos , Animais , Mastócitos , Mastocitoma Cutâneo/patologia , Mastocitoma Cutâneo/veterinária , Proteínas Proto-Oncogênicas c-kit , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/veterinária , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/patologia , Porco Miniatura , Cloreto de Tolônio
11.
J Am Vet Med Assoc ; 260(7): 741-746, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35092664

RESUMO

OBJECTIVE: To compare wound healing following planned marginal excision of cutaneous mast cell tumors (MCTs) with that of soft tissue sarcomas (STSs) and to identify risk factors for wound healing complications and delay in healing. ANIMALS: 126 dogs that underwent intentional marginal excision of cutaneous MCTs (n = 77) or subcutaneous STSs (49). PROCEDURES: Medical records of included dogs were reviewed and signalment, tumor size, tumor location, skin closure type, time to healing, reported complications, histopathological grade, and surgical margins were recorded. These variables and outcomes (complication rate and time to complete healing) were compared between dogs in the MCT and STS groups. Potential risk factors for complications and delayed healing were analyzed. RESULTS: No significant difference between the groups was found in any of the variables. Wound healing complication rates were 29% (22/77) for the MCT group and 31% (15/49) for the STS group. The mean ± SD time to complete healing was 16.5 ± 7.5 days for the MCT group and 17.7 ± 9.3 days for the STS group. These outcomes did not differ significantly between groups. For both groups, the use of subdermal plexus flap reconstruction was associated with the development of complications and increased time to complete healing. CLINICAL RELEVANCE: Marginal excision of cutaneous MCTs was not associated with a higher rate of complication or prolonged wound healing, compared with marginal excision of STSs. The use of flap reconstruction in skin closure may delay healing and planned adjuvant therapy. Owners should be counseled regarding these risks and where appropriate and feasible, surgery without reconstruction should be considered.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Sarcoma , Neoplasias de Tecidos Moles , Animais , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Mastócitos , Mastocitoma Cutâneo/veterinária , Recidiva Local de Neoplasia/veterinária , Estudos Retrospectivos , Sarcoma/cirurgia , Sarcoma/veterinária , Neoplasias de Tecidos Moles/veterinária , Resultado do Tratamento , Cicatrização
12.
J Vet Diagn Invest ; 34(2): 263-267, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34763591

RESUMO

Quantitative morphologic parameters assessed in cytologic samples of canine cutaneous mast cell tumors (ccMCTs) may assist with surgical planning and prognostication. Robust cutoffs can be defined, with high reproducibility, for parameters such as the nuclear area (NA). The NA may be determined by morphometry (image analysis, NAI) or by stereology, such as the 2D-nucleator method (NAN); stereologic techniques have not been applied to cytologic specimens of ccMCT, to our knowledge. We retrospectively selected routine cytology smears from 51 ccMCT cases and screened them to determine the percentage of neoplastic mast cells with indistinct nuclear borders; this was repeated after the slides were restained with H&E. The NAI and the NAN were estimated in 100 mast cells per animal in H&E-stained slides. All nuclei were visible in H&E smears, and unbiased quantification was feasible. The NAN was similar to NAI, but less time-consuming. Both the NAN and NAI determined by cytology differed in histologic low- and high-grade ccMCTs, and in histologic grade I plus II versus grade III ccMCTs. Stereologic parameters such as the NAN could be considered as complementary techniques for the cytologic evaluation of ccMCTs.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Animais , Citodiagnóstico/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Mastocitoma Cutâneo/patologia , Mastocitoma Cutâneo/veterinária , Reprodutibilidade dos Testes , Estudos Retrospectivos
13.
Vet Comp Oncol ; 19(3): 529-540, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33724647

RESUMO

Histological grading systems remain cornerstones in the prognosis of canine cutaneous mast cell tumours (MCTs), but the distinct biological behaviour of each tumour often necessitates the use of complementary markers. Although a plethora of immunohistochemical markers have been proposed as prognostic factors, few are presently applied in routine diagnosis. This systematic review and meta-analysis was designed to establish which immunohistochemical markers have verifiable prognostic value for cutaneous MCTs in dogs. A Boolean search of five databases identified 200 articles for screening, of which 73 were selected for full-text assessment and 24 ultimately included in the systematic review. Odds Ratio (OR) was adopted as the summary measure for subsequent meta-analysis but only 15 articles, relating to the immunomarkers Ki-67 (9), KIT (5), and BAX (2), provided either a value for OR or sufficient data to calculate this statistic. Meta-analysis verified that canine cutaneous MCTs with elevated expression of Ki-67 or BAX, as well aberrant immuno-expression of KIT, showed an increased odds of death, with respective OR values of 11.2 (95% CI 6.3-20.0; p < .01), 9.9 (95% CI 1.3-73.6; p = .03), and 4.1 (95% CI 1.1-15.3; p = .03). Despite KIT, Ki67, and BAX arise as suitable prognostic factor for canine MCTs, this study highlighted the lack of important clinical and statistical data in many published articles, rendering it impossible to complete the meta-analysis of several potentially valuable immunohistochemical markers.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Mastocitose Cutânea , Neoplasias Cutâneas , Animais , Doenças do Cão/diagnóstico , Cães , Imuno-Histoquímica , Antígeno Ki-67 , Mastócitos , Mastocitoma Cutâneo/diagnóstico , Mastocitoma Cutâneo/veterinária , Mastocitose Cutânea/diagnóstico , Mastocitose Cutânea/veterinária , Prognóstico , Proteínas Proto-Oncogênicas c-kit , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/veterinária , Proteína X Associada a bcl-2
14.
Vet Comp Oncol ; 19(4): 604-615, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32558125

RESUMO

Canine cutaneous mast cell tumours (MCTs) represent a common neoplasm in veterinary practice. Several reported techniques are available to guide surgical excision. Our study examined one hundred cutaneous MCTs that were excised surgically using a modified proportional margin approach. A 2 cm lateral margin upper limit was applied for any tumour diameter that exceeded this size with a deep surgical margin of one fascial plane applied. A retrospective, cross-sectional study with follow-up was used to determine the clinical utility of this excision technique. Associations between explanatory variables of tumour size and grade were compared with outcomes of complete excision and size of histologic tumour-free margins (HTFM) using the appropriate Pearson's χ2 and Fisher's exact tests. Follow-up data evaluated tumour recurrence and patient survival. Ninety-five percent of MCTs (95/100) were completely excised. No significant association in the achievement of complete excision between low- and high-grade MCTs (P = .48) was noted. Tumour size was not associated with the rate of complete excision (P = .06). Tumour grade and size did not influence the size of the HTFM (P = .94 and P = .14, respectively). Overall, a recurrence rate of 3% (3/100 tumours) and de novo MCT development rate of 7.7% (5/65 dogs) was noted, with median follow-up period of 593 days (range 180-1460 days). Post-operative metastases were seen in 4.6% of dogs (3/65). Therefore, a modified proportional margin approach with 2 cm lateral margin upper limit is a suitable technique to guide surgical excision of canine cutaneous MCTs.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Neoplasias Cutâneas , Animais , Estudos Transversais , Doenças do Cão/cirurgia , Cães , Margens de Excisão , Mastocitoma Cutâneo/cirurgia , Mastocitoma Cutâneo/veterinária , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/veterinária , Estudos Retrospectivos , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/veterinária
15.
J Comp Pathol ; 180: 29-34, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33222871

RESUMO

An 8-year-old neutered male French Bulldog was presented with a 2-day history of intermittent vomiting, reduced appetite and recent rapid development of multiple cutaneous masses over the head and neck regions. On presentation, the patient had a moderate volume of pericardial and bilateral pleural effusion. Echocardiography demonstrated irregular, heterogeneous thickening of the walls of the right ventricle and right atrium, consistent with infiltrative intramyocardial disease. Cytological examination of fine needle aspirates from one of the cutaneous masses confirmed a mast cell tumour. Pericardial fluid analysis revealed a haemorrhagic neoplastic effusion due to mast cell neoplasia. Histopathological and immunohistochemical examination of tissues obtained post mortem confirmed a high-grade cutaneous mast cell tumour with metastasis to the heart, pericardium, mediastinum and spleen. No metastatic disease was present in the submandibular lymph nodes or liver. Immunohistochemistry demonstrated KIT staining pattern 2. There was strong nuclear Ki67 labelling in an average of 65.0 cells per grid and an average of three positive AgNORs per nucleus in neoplastic cells. Polymerase chain reaction for the activating duplication mutation in exons 8 and 11 of c-Kit were negative. To the authors' knowledge, this is the first report of a canine cutaneous mast cell tumour associated with neoplastic pericardial effusion and widespread intrathoracic metastasis.


Assuntos
Doenças do Cão , Mastocitoma Cutâneo , Derrame Pericárdico , Animais , Doenças do Cão/diagnóstico , Cães , Masculino , Mastócitos , Mastocitoma Cutâneo/patologia , Mastocitoma Cutâneo/veterinária , Metástase Neoplásica , Derrame Pericárdico/veterinária , Proteínas Proto-Oncogênicas c-kit
16.
J Equine Vet Sci ; 87: 102921, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32172911

RESUMO

Mast cell tumor (MCT) has long been considered as an uncommon neoplasm in horses. Cytological and behavioral evidence of its malignancy is usually lacking, and only a few reports have described MCT displaying malignant behavior. An 18-year-old Friesian stallion presented with a one-year history of intermittent and progressive skin lesions on the left forelimb associated with intense, generalized pruritus and apathy temporarily responsive to glucocorticoids and antibiotics. The horse was alert and responsive with poor body condition and marked generalized pruritus. The left forelimb was markedly enlarged and surrounded by numerous firm 2- to 20-cm masses that were ulcerated and focally necrotic. A 7-cm round firm mass was observed on the left dorsal neck. Dermatological examination revealed generalized moth-eaten alopecia and scaling with erosions and ulcers secondary to pruritus. A direct skin smear from the affected leg showed severe eosinophilic inflammation and neutrophilic inflammation with pleomorphic bacteria. Histopathology of the skin and biopsies of the underlying tissues revealed an abundant population of atypical mast cells consistent with a malignant MCT. The horse was euthanized and necropsy revealed a marked fibrous reaction on longitudinal sections of the affected limb, and the tumor could be detected on only a few histological slides. Diagnosis of equine MCT can be challenging because of the massive accompanying fibrous reaction. Mast cell tumor should be suspected in the presence of eosinophilic infiltration of the affected tissue and in cases of generalized pruritus not attributable to other causes.


Assuntos
Doenças dos Cavalos , Mastocitoma Cutâneo , Neoplasias , Animais , Fibrose , Doenças dos Cavalos/diagnóstico , Cavalos , Masculino , Mastócitos , Mastocitoma Cutâneo/veterinária , Neoplasias/veterinária , Prurido/etiologia , Prurido/veterinária
17.
Rev. bras. ciênc. vet ; 26(3): 64-68, jul./set. 2019. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1491641

RESUMO

Uma égua puro sangue árabe, com 3 anos de idade, pertencente ao rebanho experimental da FMVZ-USP apresentou lesões tumorais cutâneas nos membros pélvicos direito e esquerdo com aproximadamente um ano de evolução. Notou-se nova formação cutânea com crescimento rápido na região do pescoço, e desde então, as lesões dos membros ganharam características inflamatórias. Foi realizada punção aspirativa da lesão do pescoço para análise citológica, em que se identificou infiltrado eosinofílico. Optou-se pelo início de tratamento conservativo com três infiltrações intralesionais consecutivas com corticoesteroide. A partir da falta de sucesso das infiltrações foram realizadas as excisões cirúrgicas totais dos nódulos do pescoço, membro pélvico direito e esquerdo. Todos os materiais obtidos dos procedimentos cirúrgicos foram enviados para avaliação histopatológica e imuno-histoquímica, nas quais se confirmou o diagnóstico de mastocitoma cutâneo. O animal recebeu alta após a cicatrização das feridas cirúrgicas e remissão dos sinais, e não demonstrou recidivas ou outras complicações advindas das lesões tumorais. Algumas neoplasias cutâneas são bem descritas e de comum ocorrência na espécie equina, como o sarcoide, melanoma, papiloma e tumor de células escamosas. Já o mastocitoma cutâneo consiste em neoplasia cutânea rara nessa espécie. Segundo a literatura, não parece existir uma predileção racial para o aparecimento deste tumor, entretanto, alguns autores citam o acometimento maior nos animais Puro Sangue Árabe. Para o estabelecimento do diagnóstico definitivo é importante a associação dos exames físico, histopatológico e imuno-histoquímico e, apesar desta neoplasia ser de raro aparecimento nos equinos, deve ser sempre considerada como diagnóstico diferencial.


A 3 year-old mare, Arab, that belongs to the experimental herd of FMVZ-USP presented cutaneous tumor lesions on right and left posterior limb with approximately one year of evolution. A new formation with rapid growth was observed on the neck region, and since then, the limbs lesion gained inflammatory characteristics. Aspirative punction was performed on the neck formation in order to submit the sample to cytological analyses, in which eosinophilic infiltrate was identified. At this point, a conservative approach was chosen with three consecutive corticoid infiltrations. With lack of success of infiltrative therapy, neck, right and left posterior limbs lesions were surgically removed. The materials obtained from surgical procedures were sent to histophatological and immunohistrochemical evaluation that confirmed cutaneous mastocytoma diagnosis. The mare was discharged after all surgical wound were healed and after full remission of clinical signs, and did not show relapses or any other complication from tumor lesions. Some cutaneous tumors are well described and commonly occur in horses, such as sarcoids, melanoma, papilloma and squamous cell carcinoma. Cutaneous mastocytoma is considered a rare cutaneous tumor in this species. According to literature, equine mastocytoma do not have breed predilection, however, some authors mention a greater involvement in Purebreed Arabian horses. In order to establish a definitive diagnosis, it is important to associate physical exams to histophatological an immunohistochemical evaluation and, even though rare in horses, this neoplasm must be considered as a differential diagnosis.


Assuntos
Feminino , Animais , Cavalos , Mastocitoma Cutâneo/patologia , Mastocitoma Cutâneo/veterinária , Mastocitose/veterinária , Imuno-Histoquímica/veterinária , Neoplasias Cutâneas/veterinária
18.
Rev. bras. ciênc. vet ; 26(3): 64-68, jul./set. 2019. il.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1390821

RESUMO

A 3 year-old mare, Arab, that belongs to the experimental herd of FMVZ-USP presented cutaneous tumor lesions on right and left posterior limb with approximately one year of evolution. A new formation with rapid growth was observed on the neck region, and since then, the limbs lesion gained inflammatory characteristics. Aspirative punction was performed on the neck formation in order to submit the sample to cytological analyses, in which eosinophilic infiltrate was identified. At this point, a conservative approach was chosen with three consecutive corticoid infiltrations. With lack of success of infiltrative therapy, neck, right and left posterior limbs lesions were surgically removed. The material obtained from surgical procedures were sent to histophatological and immunohistrochemical evaluation, that confirmed cutaneous mastocytoma diagnosis. The mare was discharged after all surgical wound were healed and after full remission of clinical signs, and did not show relapses or any other complication from tumor lesions. Some cutaneous tumors are well described and commonly occur in horses, such as sarcoids, melanoma, papilloma and squamous cell carcinoma. Cutaneous mastocytoma is considered a rare cutaneous tumor in this species. According to literature, equine mastocytoma do not have breed predilection, however, some authors mention a greater involvement in Purebreed Arabian horses. In order to establish a definitive diagnosis, it is important to associate physical exams to histophatological an immunohistochemical evaluation and, even though rare in horses, this neoplasm must be considered as a differential diagnosis.


Uma égua puro sangue árabe, com 3 anos de idade, pertencente ao rebanho experimental da FMVZ-USP apresentou lesões tumorais cutâneas nos membros pélvicos direito e esquerdo com aproximadamente um ano de evolução. Notou-se nova formação cutânea com crescimento rápido na região do pescoço, e desde então, as lesões dos membros ganharam características inflamatórias. Foi realizada punção aspirativa da lesão do pescoço para análise citológica, em que se identificou infiltrado eosinofílico. Optou-se pelo início de tratamento conservativo com três infiltrações intralesionais consecutivas com corticoesteroide. A partir da falta de sucesso das infiltrações foram realizadas as excisões cirúrgicas totais dos nódulos do pescoço, membro pélvico direito e esquerdo. Todos os materiais obtidos dos procedimentos cirúrgicos foram enviados para avaliação histopatológica e imuno-histoquímica, nas quais se confirmou o diagnóstico de mastocitoma cutâneo. O animal recebeu alta após a cicatrização das feridas cirúrgicas e remissão dos sinais, e não demonstrou recidivas ou outras complicações advindas das lesões tumorais. Algumas neoplasias cutâneas são bem descritas e de comum ocorrência na espécie equina, como o sarcoide, melanoma, papiloma e tumor de células escamosas. Já o mastocitoma cutâneo consiste em neoplasia cutânea rara nessa espécie. Segundo a literatura, não parece existir uma predileção racial para o aparecimento deste tumor, entretanto, alguns autores citam o acometimento maior nos animais Puro Sangue Árabe. Para o estabelecimento do diagnóstico definitivo é importante a associação dos exames físico, histopatológico e imuno-histoquímico e, apesar desta neoplasia ser de raro aparecimento nos equinos, deve ser sempre considerada como diagnóstico diferencial.


Assuntos
Animais , Neoplasias Cutâneas/veterinária , Imuno-Histoquímica/veterinária , Técnicas de Laboratório Clínico/veterinária , Mastocitose Cutânea/veterinária , Mastocitoma Cutâneo/veterinária , Cavalos/cirurgia
19.
PLoS Genet ; 15(3): e1007967, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30901340

RESUMO

Mast cell tumours are the most common type of skin cancer in dogs, representing a significant concern in canine health. The molecular pathogenesis is largely unknown, but breed-predisposition for mast cell tumour development suggests the involvement of inherited genetic risk factors in some breeds. In this study, we aimed to identify germline risk factors associated with the development of mast cell tumours in Labrador Retrievers, a breed with an elevated risk of mast cell tumour development. Using a methodological approach that combined a genome-wide association study, targeted next generation sequencing, and TaqMan genotyping, we identified a synonymous variant in the DSCAM gene on canine chromosome 31 that is associated with mast cell tumours in Labrador Retrievers. DSCAM encodes a cell-adhesion molecule. We showed that the variant has no effect on the DSCAM mRNA level but is associated with a significant reduction in the level of the DSCAM protein, suggesting that the variant affects the dynamics of DSCAM mRNA translation. Furthermore, we showed that the variant is also associated with mast cell tumours in Golden Retrievers, a breed that is closely related to Labrador Retrievers and that also has a predilection for mast cell tumour development. The variant is common in both Labradors and Golden Retrievers and consequently is likely to be a significant genetic contributor to the increased susceptibility of both breeds to develop mast cell tumours. The results presented here not only represent an important contribution to the understanding of mast cell tumour development in dogs, as they highlight the role of cell adhesion in mast cell tumour tumourigenesis, but they also emphasise the potential importance of the effects of synonymous variants in complex diseases such as cancer.


Assuntos
Moléculas de Adesão Celular/genética , Mastocitoma Cutâneo/genética , Mastocitoma Cutâneo/veterinária , Animais , Adesão Celular/genética , Doenças do Cão/genética , Cães , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Células Germinativas , Mutação em Linhagem Germinativa/genética , Mastócitos/metabolismo , Mastócitos/fisiologia , Mastocitoma Cutâneo/metabolismo , Mastocitose Cutânea/genética , Fatores de Risco , Mutação Silenciosa/genética , Neoplasias Cutâneas/genética
20.
Pesqui. vet. bras ; 39(1): 52-60, Jan. 2019. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-990230

RESUMO

Due to the high prevalence of mast cell tumors (MCTs) in the diagnostic routine, several factors, especially prognostic, have been sought to determine the biological behavior of these neoplasms. Immunohistochemistry (IHC) is one of the main tools utilized to biologically differentiate more aggressive tumors from less aggressive ones. However, some immunostainings are influenced by formalin fixation, interfering with the results. This is both a retrospective and prospective study of MCTs diagnosed in laboratory routine. A total of 25 samples, without knowledge about fixation time, were analyzed in the retrospective study, whereas 12 samples, with known fixation times, were assessed in the prospective study. Two histologic grading systems (Patnaik and Kiupel), special staining of toluidine blue, and IHC for KIT and Ki67 proteins were applied in both studies. Additionally, two amplification systems (biotinylated and non-biotinylated) for Ki67 protein and counting of the argyrophilic nucleolar organizing regions (AgNOR method) were tested in the prospective study. In the retrospective study, greater agreement between the evaluating pathologists was observed when the Kiupel system was used. IHC staining for KIT protein was effective in both studies, regardless of fixation time. IHC staining for Ki67 protein was highly sensitive to formaldehyde, and staining failure was observed in 56% of the cases in the retrospective study. In the prospective study, samples fixed for longer than 24 hours showed a reduction in the number of stained cells (altering the determination of the cell growth fraction) or showed absence of IHC staining in both amplification systems. The use of the AgNOR method to evaluate the rate of cell proliferation may be an alternative when the fixation time of the neoplasm is unknown or longer than 24 hours.(AU)


Devido a alta prevalência dos mastocitomas cutâneos caninos (MCCs) na rotina diagnóstica, vários fatores, especialmente fatores prognósticos, têm sido buscados para auxiliar na determinação do comportamento biológico desse neoplasma. A imuno-histoquímica é uma das principais ferramentas empregadas para diferenciar tumores biologicamente mais agressivos de tumores menos agressivos. Entretanto, algumas imunomarcações sofrem influência pela fixação em formol, interferindo nos resultados. Este estudo compreendeu avaliar através de uma etapa retrospectiva e uma etapa prospectiva casos de MCCs diagnosticados na rotina laboratorial. Um total de 25 amostras, sem conhecimento do tempo de fixação, foi analisado no estudo retrospectivo e 12 amostras, com tempos de fixação conhecidos, no estudo prospectivo. Foram aplicados nos dois estudos, dois sistemas de graduação histológica (Patnaik e Kiupel), a coloração especial de azul de toluidina e a imuno-histoquímica para as proteínas KIT e Ki67. Adicionalmente, no estudo prospectivo, foram testados dois sistemas de amplificação (biotinilado e não biotinilado) para a proteína Ki67 e a técnica de AgNOR (contagem das regiões organizadoras nucleolares argirofílicas). Na etapa retrospectiva, observou-se uma maior concordância entre os patologistas avaliadores quando o sistema Kiupel foi utilizado. A imunomarcação para KIT se manteve eficaz em ambos os estudos, independentemente do tempo de fixação. A imunomarcação para o Ki67 mostrou-se altamente sensível ao tempo de fixação em formol, sendo observada falha na imunomarcação em 56% dos casos do estudo retrospectivo. No estudo prospectivo, constatou-se que amostras fixadas por mais de 24 horas em formol apresentaram redução na quantidade de células imunomarcadas (alterando a determinação da fração de crescimento celular) ou apresentaram ausência de imunomarcação em ambos os sistemas de amplificação. A utilização do método AgNOR, para avaliar a taxa de proliferação celular, pode ser uma alternativa quando o tempo de fixação do neoplasma for desconhecido ou superior a 24 horas.(AU)


Assuntos
Animais , Cães , Cães , Mastocitoma Cutâneo/diagnóstico , Mastocitoma Cutâneo/imunologia , Mastocitoma Cutâneo/ultraestrutura , Mastocitoma Cutâneo/veterinária , Proteínas Proto-Oncogênicas c-kit
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