Katia Barão Corgozinho

Catheter-induced urethral trauma in cats with urethral obstruction

Fifteen cats were evaluated with urethral obstruction. Penile trauma by catheterization was the major indication for perineal urethrostomy. Ten cats had developed a urethral stricture and five had rupture of the urethra following medical management. All cats had abnormalities in penis and/or prepuce and/or scrotal sacs including hyperemia or swelling. Perineal urethrostomy was performed in all cases and they were evaluated for 6 months after surgery. Few complications were noted. Urinary tract infection was the most frequent complication observed. The clients considered their cats to have a good quality of life following surgery.

Management of the traumatic oronasal fistula in the cat with a conical silastic prosthetic device

Management of a traumatic oronasal fistula with a prosthetic device in an 8-year-old male neutered domestic shorthair cat is described. The animal had fallen from a height of three stories at the age of 1 year. The fall had resulted in a fracture of the hard palate and a split in the palatal mucosa. Two surgical attempts to close the defect had been unsuccessful and an autopolymerizable acrylic resin prosthesis had produced unsatisfactory results. The management of the chronic traumatic fistula with a conical prosthetic device was fast, easy and efficient. The device was removed and a second one was put in place after 2 years. This method would appear particularly useful for obturation of large palatal defects that have failed to heal after attempts at surgical closure and is an alternative treatment for debilitated cats which may not be candidates for longer surgical procedures.

Duodenal perforation caused by Rhizomucor species in a cat.

Clinical summary A 7-month-old female Persian cat presented with gastrointestinal (GI) necrosis and perforation caused by Rhizomucor species. Unfortunately, the cat died of bacterial peritonitis and sepsis before a definitive diagnosis, based on histopathology and fungal culture, was achieved. Practical relevance This appears to be the first reported case of GI disease caused by Rhizomucor species in a cat. Mucorales infections typically cause acute and rapidly progressive disease. As illustrated by this case, clinicians should be alert to the potentially fatal consequences of an opportunistic Rhizomucor species infection in their feline patients.

Adjuvant chemotherapy with mitoxantrone for cats with mammary carcinomas treated with radical mastectomy

Objectives The purpose of this study was to investigate the disease-free interval, survival time and adverse events of a combined treatment approach in cats with mammary malignant tumors using radical mastectomy and adjuvant mitoxantrone. Methods All cats underwent surgery to remove the mammary chain containing the tumors. A 3 cm margin was obtained around removed tumors. For staging purposes, regional inguinal lymphadenectomy was performed in all cases. After histopathology, cats were staged according to the World Health Organization’s (WHO) staging system. Chemotherapy with mitoxantrone was started 15–30 days after surgery (6 mg/m2 IV every 21 days for four cycles) with the objective of delaying metastasis. Results Three cats were intact, one cat was early spayed, four cats were late spayed and four cats were spayed at an unknown age. Based on the WHO’s staging system, six cats were classified as stage I and six cats as stage III. The median disease-free interval and survival time were 360 and 480 days, respectively. Four (33%) cats received four doses of mitoxantrone, four (33%) cats received three doses and four (33%) cats received only one dose. The most frequent adverse effects of chemotherapy were azotemia, anorexia, leukopenia and vomiting. Conclusions and relevance Adjuvant mitoxantrone chemotherapy may be an option for feline mammary tumors. Further, sufficiently powered, randomized prospective trials are necessary to determine if mitoxantrone is superior, inferior or equivalent to doxorubicin in the adjuvant setting.

Survival and Disease-free Interval of Cats with Mammary Carcinoma Treated with Chain Mastectomy

Background: Mammary tumors are extremely common in cats and have high metastatic rates with poor prognosis. The main objective of the present study was to evaluate the disease free interval and survival in cats undergoing radical mastectomy as sole therapy. Materials, Methods & Results: Twenty cats with mammary tumors and no evidence of distant metastasis were studied. General health and concomitant diseases were assessed by clinical and hematological examination. Thoracic radiographs and abdominal ultrasonography were performed to evaluate thoracic and abdominal metastases. All cats underwent chain mastectomy, which was unilateral when tumor was present in one mammary chain, and bilateral in steps if tumors were present in both mammary chains. Intact cats were spayed. An elliptical incision was made around the mammary chain with a three centimeter margin around tumor. Regional lymph node was removed. Mean age was ten years, and 14 cats were mixed breed, three were Persian and two were Siamese. Fifteen cats were spayed at tumor diagnosis, but only three had been spayed before one year old. The inguinal mammary glands were the most affected, followed by abdominal and thoracic glands. Histopathology diagnosed well-differentiated adenocarcinoma in eight cases, moderately differentiated adenocarcinoma in nine cases, poorly differentiated adenocarcinoma in two cases and carcinoma in situ in one case. Most tumors were grade II, and regional lymph node metastasis was present in two cases. Disease free interval ranged from 120 to 1800 days, with an average of 678 days. Four cats had tumor local recurrence and six developed lung metastasis. The survival time ranged from seven to 1800 days, with an average of 768 days. Twelve cats are still alive with no tumor recurrence. Discussion: The average age of onset of mammary carcinomas in cats was ten years old, similar to previous studies. Siamese cats have more risk of developing this disease, but mixed breed cats were frequent in this study. Intact or late spayed cats are predisposed to mammary tumors because of hormonal stimulation, the same was observed in this study. Inguinal and abdominal glands were most affected, similar to other reports. The histopathologic diagnosis was adenocarcinoma in most cases of this study, mostly grade II tumors, which was also observed in previous papers. Regional lymph nodes (axillary or inguinal) should always be removed during mastectomy in cats, as regional metastasis at diagnosis is common, even when not clinically palpable, as was observed in two cases. Distant metastasis occurs most often to the lungs, leading to severe dyspnea. In this study, four cats had local tumor recurrence and six developed lung metastasis. Aggressive and early surgical intervention is the treatment of choice for feline mammary tumors. Unlike dogs (where conservative mammary resections are appropriate in some cases), radical chain mastectomy is recommended for feline mammary tumors, as significantly reduces the risk of local recurrence. In this study, all animals underwent radical mastectomy, without previous cytology or biopsy. Survival is variable between studies, ranging from 220 to 1408 days. Several factors may be involved in disease free intervals and survival times, as tumor size, tumor histological grade, presence of metastasis at diagnosis, type of surgery performed, presence of concomitant diseases and adjuvant chemotherapy. In this study, mean survival time was 768 days and 12 cats are still alive and in follow-up, which may increase this number. This study supports that, if treated early and agressively, cats with malignant mammary tumors can have long survival after chain mastectomy.

Tratamento de um mastocitoma de alto grau na língua de um cão por meio de radioterapia e quimioterapia: relato de caso

Um canino da raca Boxer, femea, de oito anos de idade, foi atendido com salivacao, halitose e disfagia. No exame clinico, foi observada uma massa ulcerada no terco medio da lingua medindo 3,5 x 4,0cm. A histopatologia e a imuno-histoquimica levaram ao diagnostico de um mastocitoma de alto grau. O tratamento cirurgico (glossectomia parcial) foi declinado pelo proprietario, sendo a radioterapia indicada em seu lugar. O protocolo radioterapico empregado foi 15 fracoes de 300cGy, realizadas cinco vezes por semana. O equipamento utilizado foi de ortovoltagem. A lesao neoplasica apresentou remissao clinica completa a partir da quarta sessao radioterapica. O unico efeito colateral observado foi mucosite leve na regiao irradiada, que, entretanto, nao levou a sintomas clinicos. A quimioterapia sistemica consistiu de vimblastina e lomustina, alternadas a cada 14 dias, durante quatro meses. Ate o momento (22 meses apos o tratamento), nao ha evidencias de recidiva local ou metastases do mastocitoma. A associacao da radioterapia e da quimioterapia pode ser considerada uma alternativa terapeutica nos casos de mastocitomas irressecaveis, ja que, neste caso, levou a remissao completa e duradoura de um tumor agressivo, com otima tolerância do paciente ao tratamento e posterior qualidade de vida.

Esophageal stricture caused by rib osteoma in a cat: case report

Case summary A 6-year-old male domestic shorthair cat presented with frequent food regurgitation and dysphagia. Plain thoracic radiographs revealed a calcified mass overlying the topography of the mediastinum, as well as dilation of the cervical portion of the esophagus due to an accumulation of food. Endoscopic examination showed a severe extraluminal esophageal stricture at the mediastinum entrance. Surgery and a gastric tube were declined by the cat’s owner, with palliative support preferred. However, 1 year later, the cat presented with severe cachexia, dysphagia, salivation, dehydration and inspiratory dyspnea. Thoracic computed tomography was performed to evaluate the possibility of surgical resection. A mass of bone density originating in the second left rib was observed. The mass did not appear to have invaded adjacent structures but marked compression of the mediastinal structures was observed. Surgical resection was performed and a prosthetic mesh was used to reconstruct the thoracic wall. Transient Horner’s syndrome developed in the left eye postoperatively, and was resolved within 4 weeks. Histopathology revealed a benign osteoma. Thirty-two months after surgery, the cat was well and free of disease. Relevance and novel information Rib tumors should be included in a differential diagnosis in cats with extraluminal esophageal stricture. CT should be performed for treatment planning. Surgical treatment was curative in this case.

Successful subtotal orbitectomy in a cat with osteoma

Case summary A 14-year-old Siamese neutered male cat was evaluated for anorexia and a left periorbital mass. Skull radiographic findings showed a well-defined lesion resembling new compact bone formation without destruction. A subtotal orbitectomy was indicated. The tumor was removed intact with a normal tissue margin of at least 1 cm. There were no postsurgical complications. Histopathologic examination revealed an osteoma. The cat returned to normal appetite and activity 15 days after surgery. Six months after surgery, there were no gross signs of recurrence. Relevance and novel information Periorbital tumors are infrequently diagnosed in companion animals and most are malignant. In this case, the diagnosis was orbital osteoma. The most commonly affected bone for osteoma in cats is the mandibular bone; few cases have been identified in orbital bones. Orbital surgery has the potential to be challenging owing to complex anatomy, difficult exposure and the tendency to bleed. Surgical complications are common. In this case, although the disease was advanced, subtotal orbitectomy was successfully performed.