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Background: Thyroid tumor is a common endocrine tumor that accounts for up to 3.8% of all tumors in dogs. Most of them are malignant and usually nonfunctional in dogs. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is an imaging modality that detects intracellular accumulation of radioactive deoxyglucose administered in the body and is used in combination with computed tomography to provide functional information with exact anatomical localization. It is used in human medicine to detect residual or recurrent head and neck neoplasm after treatments, such as surgical resection. This report describes the first case of diagnosing recurrent thyroid carcinoma (TC) through FDG-PET in a dog. Case: A 9-year-old castrated male Maltese dog presented with a palpable mobile mass in the right ventral cervical region. Radiography and ultrasonography (US) showed a radiopaque mass adjacent to the trachea, and the right thyroid gland was enlarged on computed tomography. The surgically excised mass was encapsulated and measured to be 2.3 × 1.0 × 3.4 cm (width x length x height) in size. Histopathologically, the mass was diagnosed as differentiated follicular TC, and gross and vascular invasions were observed. To prevent recurrence, postoperative carboplatin chemotherapy was performed for 5 months. Two months after completion of chemotherapy, a nodule of approximately 7 mm in diameter was detected in the thyroidectomy bed by US. FDG-PET scanning was performed as an effective means of evaluating the malignancy, local recurrence, and metastasis of differentiated follicular TC. The nodule had the dimensions of 2.8 × 5.9 × 8.6 mm, a maximum standardized uptake value (SUV) of 8.49, and a mean SUV of 5.6. The results of FDG-PET suggested the recurrence of TC; therefore, the second chemotherapy protocol using toceranib was applied for 16 months. After initiation of the 2nd chemotherapy, follow-up examinations were conducted approximately every 4 months. On the 134th day, although the nodule was not palpated, its size was observed to have increased to 5.0 × 3.8 × 13.6 mm on cervical US on the 232nd day, showing heterogeneous and hypoechoic parenchyma. On the 405th day, the tumor was enlarged to a size of 13.4 × 12.9 × 22 mm and identified as a lobular, amorphous shape, and its heterogeneity was increased. Moreover, 2 pulmonary nodules with well-defined margins were found on radiography in the left caudal lung lobe (9 × 10 mm and 12 × 12 mm [width × length]); thus, lung metastasis was suspected. On the 536th day, anorexia and lethargy occurred, and the dog was lost to follow-up. Discussion: In the present case, local recurrence of TC was suspected based on cervical US. Although US was useful as a screening tool, additional examinations were necessary for evaluating local invasiveness, malignancy, and nodal/distant metastasis. FDG-PET can detect recurrence at an early stage because it can sense increased tumor metabolism through physiologic absorption of FDG, even before the beginning of anatomic change in the lesion. Therefore, FDG-PET can assist in treatment planning and provide better prognosis. In humans, focal FDG uptake and a high maximum SUV in the thyroid gland on FDG-PET were associated with a higher risk of cancer. Because there was no evidence of neoplasia except the thyroid lesion during the FDG-PET examination, the tumor showed an increasingly malignant pattern of the thyroid gland on US during the follow-up period, and the metastatic pulmonary nodules were identified on the 650th day after the thyroidectomy, the present case was diagnosed as recurrent TC. This report describes the use of FDG-PET for diagnosing local recurrence of TC, pointing to FDG-PET as a potential strategy to evaluate loco-regional recurrence and distant metastasis of TC.

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Mammary neoplasia represents the most frequently diagnosed type of neoplasia in bitches. Although surgical removal is the procedure of choice for therapeutic management, chemotherapy protocols appear as important allies and adjuvants. Despite the great advances that have occurred in the field of cancer therapy, the systemic repercussions of these drugs still impose important limitations on their use. In this sense, the development of increasingly targeted therapeutic protocols and preventive monitoring of patients represent important strategies to avoid possible complications - among them, Acute Kidney Injury (AKI). Routinely, ultrasound evaluation is used to identify morphological or metastatic variations in abdominal cavity organs. Acting complementary to the B-mode evaluation, Doppler mapping proves to be efficient in recognizing alterations in vascular hemodynamics. Therefore, the objective of the present study was to evaluate the use of B-mode and Doppler ultrasound to identify renal morphological and hemodynamic alterations in bitches with mammary neoplasia submitted to adjuvant chemotherapy protocols that associate gemcitabine with carboplatin. Thirteen bitches were included, without distinction of breed and between seven and 13 years of age. The animals were evaluated ultrasonographically at two different times during three consecutive chemotherapy cycles: before (T0) and one and a half hours after each cycle (T1), for 42 days. No morphological changes were observed in B-mode throughout the chemotherapy protocol. However, the Doppler velocimetry indices demonstrated statistical differences before (T0) and after (T1) the administration of the drugs. It was concluded that Doppler ultrasound could be used as a complementary method for monitoring the renal response of patients exposed to nephrotoxic drugs and potentially causing renal injury.

As neoplasias mamárias representam o tipo de neoplasma mais frequentemente diagnosticado em fêmeas da espécie canina. Embora a remoção cirúrgica seja o procedimento de eleição para a conduta terapêutica, os protocolos quimioterápicos aparecem como importantes aliados e adjuvantes. Apesar dos grandes avanços ocorridos na área da terapia oncológica, as repercussões sistêmicas destes fármacos ainda impõem importantes limitações ao seu uso. Neste sentido, o desenvolvimento de protocolos terapêuticos cada vez mais direcionados e o monitoramento preventivo dos pacientes representam estratégias importantes para evitar possíveis complicações - dentre elas, a injúria renal aguda (IRA). Rotineiramente, a avaliação ultrassonográfica é utilizada para identificação de variações morfológicas ou metastáticas em órgãos da cavidade abdominal. Atuando de forma complementar à avaliação em modo-B, o mapeamento Doppler mostra-se eficiente no reconhecimento de alterações na hemodinâmica vascular. Portanto, o objetivo do presente estudo foi avaliar a utilização da ultrassonografia modo-B e Doppler como método para identificação de alterações morfológicas e hemodinâmicas renais em cadelas com neoplasias mamárias submetidas a protocolos quimioterápicos adjuvantes que associam a gencitabina à carboplatina. Foram incluídas 13 fêmeas caninas, sem distinção quanto a raça e com idades entre sete e 13 anos. Os animais foram avaliados ultrassonograficamente em dois momentos distintos durante três ciclos quimioterápicos consecutivos: antes (T0) e uma hora e meia após a realização de cada ciclo (T1), totalizando 42 dias. Não foram observadas alterações morfológicas em modo-B ao longo do protocolo quimioterápico. Entretanto, os índices dopplervelocimétricos demonstraram diferenças estatísticas antes (T0) e após (T1) a administração dos fármacos. Concluiu-se que a ultrassonografia Doppler pode ser utilizada como método complementar para o monitoramento da resposta renal de pacientes expostos a fármacos nefrotóxicos e potencialmente causadores de injúrias renais.

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Background: Melanocytic neoplasm can arise from melanocytes in any location of the body. Malignant melanoma (MM)has a poor prognosis in dogs and presence of lymphvascular invasion, distant metastasis, or mitotic activity present prognostic value. Primary melanoma affecting the gastrointestinal tract has been rarely reported in veterinary literature, thusthe prognosis affecting gastrointestinal tract is unknown. Electrochemotherapy (ECT) is an effective local treatment whichcombines chemotherapeutic drugs mainly bleomycin or cisplatin followed by the delivery of permeabilizing electricalpulses However, other hydrophilic drugs seem to present an increase cytotoxic effect such as carboplatin.Case: A 9-year-old mixed-breed neutered dog was referred to a private clinic with a mass in the perianal region diagnosedas perianal melanoma. No metastasis was observed on abdominal ultrasound nor chest x-ray (3 views). Clinical signs notedwere tenesmus, hemorrhagic discharge, weight loss and hyporexia. Considering the tumor volume (16.0 x 10.0 cm), a neoadjuvant ECT session was proposed. The authors opted for carboplatin (300 mg/m2, intravenously), administered over 20min and cisplatin intratumorally (1 mg/cm3, equivalent to 1 mL/1cm3 total volume 20 mL) administered in the upper partsof the mass that could be reached while avoiding drug leakage. After administration, sequences of eight biphasic pulses,(100 microseconds), with a voltage ranging from 650-1,000V/cm (pulse generator Onkodisruptor®) using a hexagonal/single pair and plate electrode were delivered. At day 30th, a partial response was observed accordingly to RECIST system,with tumor size of 5.0 x 5.0 cm (65.4 cm3). A second ECT session was performed with the same previous protocol, butwith a decreased dosage of carboplatin (240 mg/m2 consistent with 20% reduction) due to adverse effects in the first session, resulting in stable disease at day 60th (30 days after second ECT). Then...

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Background: Urethral tumors are uncommon in canines, represented predominantly by transitional cell carcinoma, marked by aggressive behavior associated with short life expectancy. Definitive diagnosis is achieved by histopathological analysis. Surgery associated with chemotherapy is the main therapeutic alternative. The aim of this paper is to report a case of primary transitional cell carcinoma of the urethra in a bitch, submitted to surgical treatment associated with conventional adjuvant chemotherapy and metronomic chemotherapy, achieving survival of 21 months, to date. Case: A 12-year-old bitch mixed breed was admitted at the Veterinary Hospital of Federal Rural University of Rio de Janeiro (UFRRJ), manifesting hematuria and urinary incontinence for one month. Physical examination indicated that vital parameters were within normal limits. Laboratory tests of blood count and serum biochemistry, urinalysis, culture, urinary antibiogram, and abdominal ultrasound were performed. The ultrasound image suggested a neoplastic urethral process. Because of the suspicion of neoplasm, a thoracic X-ray was performed, showing no evidence of metastasis. Computed tomography (CT) of the abdominal region was performed, revealing an expansive lesion in the urethra with loss of definition of the walls and urethral lumen extending to the level of the pelvic floor, measuring about 2.9 x 1.4 x 1.2 cm. After preanesthetic exams, the animal underwent resection and surgical anastomosis of the affected urethral region. The sectioned tissue was sent for histopathological analysis, with diagnosis of transitional cell carcinoma. Adjuvant chemotherapy was performed using carboplatin at a dose of 250 mg/m², intravenously, every 21 days for 6 sessions. After completing the protocol, abdominal ultrasonography was performed again, which showed a cicatricial process in the urethral region of the surgical excision, with no sign of tumor recurrence. A metronomic chemotherapy protocol was then started with cyclophosphamide at a dose of 15 mg/m², daily for 6 months, with periodic oncological follow-up. At the end of the period, the animal remained under periodic follow-up with ultrasound exams performed at 2-month intervals, and has been free from recurrence for 21 months until now. Discussion: Urethral neoplasms account for 0.5 - 2% of all canine tumors, and are represented mostly by transitional cell carcinomas. Clinical signs of urinary obstruction and hematuria are the most common, as reported in the patient in question. The definitive diagnosis is by histopathological examination. However, imaging tests such as computed tomography are important in the initial investigation and surgical planning. The indicated treatment is surgical resection of the mass with subsequent adjuvant chemotherapy or radiotherapy. The chemotherapy protocol associating cisplatin and piroxicam can achieve remission rates of 70%, but this association has a high nephrotoxic effect. In the present case, cisplatin was replaced by carboplatin in order to reduce the nephrotoxic effects of chemotherapy. The metronomic protocol using cyclophosphamide was used as maintenance therapy, at the end of the conventional chemotherapy protocol. Survival achieved was longer than that described in the literature in cases of transitional cell carcinomas in the urethral region. Therefore, multimodal therapy using surgery associated with conventional and metronomic chemotherapy, is an option in canines with urethral carcinoma.

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In breast cancer treatment, chemotherapy resistance is a major problem where many receptive tumors rebound and develop resistance. When provided in combination, cancer drugs are most successful, thus reducing the risk of developing resistant cancer cells. However, the evaluation of combination therapies has increased rapidly in recent years. Consequently, by repurposing old treatments, the discovery of additional medicines that may interact synergistically with chemotherapy is considered a current medical aim through discovering a new cancer medication or therapeutic strategy. The purpose of this research is to increase the anti-cancer activity of carboplatin (CP) by increasing the apoptotic effect of breast cancer cells (MCF-7) during in vitro experiments in combination with oxytetracycline. Our results showed a high synergistic effect between oxytetracycline and carboplatin, MCF-7 representative cell treated with carboplatin with/without different concentrations of oxytetracycline (5% and 10% of IC50). Oxytetracycline, which potentiated the action of carboplatin and/or had notable activity was reported as a single agent. This research demonstrated the synergistic relationship between oxytetracycline and carboplatin in viability assays. Surprisingly, our findings suggest that inhibiting treatment strategies can extend carboplatin's therapeutic window, potentially allowing for cancer therapy.(AU)

No tratamento do câncer de pulmão a resistência à quimioterapia é o maior problema no qual muitos tumores receptivos apresentam um rebote e desenvolvem a resistência. Quando oferecidas em combinações, as drogas anticancerígenas apresentam maior taxa de sucesso, reduzindo assim o risco de desenvolvimento de células cancerígenas resistentes. Contudo, a avaliação das terapias de combinação tem crescido muito rapidamente. Consequentemente, por reaproveitamento de tratamentos antigos, a descoberta de novos medicamentos adicionais que podem interagir sinergicamente com a quimioterapia que é considerada como auxílio médico na corrente busca à descoberta de novas medicações anticancerígenas ou estratégias terapêuticas. O propósito da presente pesquisa é aumentar a atividade anticancerígena da Carboplatina (CP) pelo incremento do efeito apoptótico de células de câncer pulmonar (MCF-7) em experimentos in vitro pela combinação com oxitetraciclina. Os resultados obtidos confirmaram elevado efeito sinérgico entre oxitetraciclina e Carboplatina em células MCF-7 representativas tratadas com Carboplatina, com e sem diferentes concentrações de oxitetraciclina (5% e 10% de IC50). A oxitetracilina que potencializou a ação da Carboplatina e/ou teve uma notável atividade relatada como um agente isolado. A pesquisa demonstrou a relação sinérgica entre oxitetraxiclina e Carboplatina nos ensaios de viabilidade. Surpreendentemente, os resultados obtidos sugeriram que as estratégias de tratamento inibidor podem aplicar um janela terapêutica da Carboplatina com potencial para a terapia do câncer.(AU)

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Feline Injection Site-Associated Sarcoma (FISS) is a neoplasm that implies in reduction of quality of life and overall survival in feline patients. A retrospective study of 13 cases of FISS was conducted to evaluate the efficacy of surgical treatment associated to chemotherapy with doxorubicin or carboplatin. Local recurrence occurred in all patients. Patients treated with surgery and chemotherapy presented a longer overall survival and disease-free interval when compared to those that solely received surgical treatment, although no statistical significance was observed (p= 0.3360 and 0.7506, respectively). Surgery remains as the main option for FISS treatment. Further prospective studies with larger samples are warranted to investigate the benefit of chemotherapy for this neoplasm.(AU)

O Sarcoma de Aplicação Felino (SAF) é uma neoplasia associada a redução na qualidade de vida e sobrevida global. O objetivo deste estudo foi avaliar a eficácia da quimioterapia associada à cirurgia no manejo do SAF. Estudo retrospectivo de 13 pacientes com SAF submetidos à cirurgia isolada ou associada a quimioterapia com carboplatina ou doxorrubicina. Recorrência local ocorreu em todos os pacientes. Pacientes tratados com cirurgia e quimioterapia apresentaram maior sobrevida global e intervalo livre de doença quando comparados àqueles que receberam apenas tratamento cirúrgico, mas não foi observada diferença estatística (p=0,3360 e 0,7506, respectivamente). A cirurgia continua sendo a principal opção para o tratamento do SAF. Estudos prospectivos são necessários para investigação do real benefício da quimioterapia para esta neoplasia.(AU)

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A transitional cell carcinoma of the renal pelvis was diagnosed in a 10-year-old, male German shepherd that presented with a 1-month history of hematuria and weight loss. Unilateral nephrectomy and chemotherapy with carboplatin was applied, but the dog was euthanized five months after the surgery due to metastasis.