Lisa A. Mestrinho

Efficacy of systemic adjuvant therapies administered to dogs after excision of oral malignant melanomas: 151 cases (2001-2012)

OBJECTIVE To determine prognostic factors for and compare outcome among dogs with oral malignant melanoma following excision with or without various systemic adjuvant therapies. DESIGN Retrospective case series. ANIMALS 151 dogs with naturally occurring oral malignant melanomas treated by excision with or without adjuvant therapies from 2001 to 2012. PROCEDURES Case accrual was solicited from Veterinary Society of Surgical Oncology members via an email list service. Information collected from case records included signalment, tumor staging, tumor characteristics, type of surgical excision, histologic diagnosis, adjuvant therapy, and survival time. RESULTS The overall median survival time was 346 days. Results of multivariate analysis indicated that tumor size, patient age, and intralesional excision (vs marginal, wide, or radical excision) were considered poor prognostic indicators. All other demographic and clinical variables were not significantly associated with survival time after adjusting for the aforementioned 3 variables. A clear survival benefit was not evident with any systemic adjuvant therapy, including vaccination against melanoma or chemotherapy; however, the number of dogs in each treatment group was small. Ninety-eight dogs received no postoperative adjuvant therapy, and there was no difference in survival time between dogs that did (335 days) and did not (352 days) receive systemic adjuvant therapy. CONCLUSIONS AND CLINICAL RELEVANCE For dogs with oral malignant melanoma, increasing tumor size and age were negative prognostic factors. Complete excision of all macroscopic tumor burden improved survival time. Long-term survival was possible following surgery alone. Although systemic adjuvant therapy was not found to improve survival time, this could have been due to type II error.

p63 and E-cadherin Expression in Canine Oral Squamous Cell Carcinoma:

The expression of p63 and E-cadherin was studied in 22 oral squamous cell carcinomas in the dog according to immunohistochemical techniques. The association between these markers and clinicopathologic parameters was assessed. All tumor cells studied showed enhanced p63 expression. Regarding E-cadherin expression, 17 of 22 cases (77.3%) showed decreased immunoreactivity, and in 13 of 22 cases (59.1%), its expression was cytoplasmic. Neither p63 nor E-cadherin expression patterns were associated with tumor size, bone invasion, or lymph node metastasis. p63 score was related to proliferating cell nuclear antigen proliferative index (P = .020). A statistically significant correlation between the expression patterns of these 2 markers was noted (P = .026). Furthermore, they were related with tumor grade. An atypical p63 labeling and a cytoplasmic E-cadherin staining were statistically related with a higher tumor grade (P = .022 and P = .017, respectively). These findings suggest that changes in p63 and E-cadherin expression are frequent events in oral squamous cell carcinoma in dogs.

Open surgical correction combined with an external splint for correction of a non-compliant pectus excavatum in a cat:

A 4-month-old domestic shorthair female cat weighing 1.3 kg was presented for evaluation of respiratory distress. The animal showed evident dyspnoea with exercise intolerance and a marked concave deformation of the sternum. After measurements of the fronto-sagittal and vertebral indexes, the pectus was classified as moderate and surgery was elected. Surgical correction was performed using an open approach to the sternum with osteotomy of the last sternebra and costochondral junctions of the eighth and ninth ribs bilaterally. A silicone based, U-shape external splint was manufactured and used to stabilise the sternum. Immediate and 5-week postsurgical radiographs revealed a decreased concavity of the sternum and an increase thoracic height at the level of the last sternebra. Postoperative results suggest that this technique could be an effective and economical option for cats with pectus excavatum with a non-compliant sternum.

PCNA and grade in 13 canine oral squamous cell carcinomas: association with prognosis.

This study evaluated the prognosis factors of age, tumour size, anatomic location, histological grade and proliferating cell nuclear antigen (PCNA) expression in 13 dogs with oral squamous cell carcinoma (OSCC) with bone invasion and without signs of lymph node or distant metastasis. All animals were treated with radical excision performed with at least 1 cm margin, based on computed tomography images. In the 2-year follow-up, median disease-free survival was 138 days for dogs with grade 3 tumours and was not reached for those with grade 2 tumours. Grade 3 tumours and PCNA labelling index ≥65% were related with a shorter disease-free survival time and consequently poor prognosis (p = 0.003 and p = 0.034, respectively). Mean PCNA labelling index was significantly higher in recurrent cases (p = 0.011). Histological grade and PCNA expression may be important prognosis factors in canine OSCC.

Risk Assessment of Feline Tooth Resorption: A Portuguese Clinical Case Control Study

Tooth resorption (TR) is one of the most common dental diseases in cats. Determination of risk factors has not yet been fully assessed and, to the best knowledge of the authors, this disease has never been studied in Portuguese cats. The objective of this case-control study was to determine type and distribution of TR lesions, evaluate risk factors, and establish relationships between variables in this disease. The study included data from 71 cats admitted for general anesthesia for various reasons. The cats were randomly selected. The inclusion criteria were availability of clinical history and owner permission. Cats with known oral disease were not excluded from the study. All cats received ultrasonic scaling and polishing of the teeth, a thorough oral examination, and full-mouth radiographs. A strong statistical relation was found between age and TR. The age group of 10 to 15-years showed an increased risk of 6.56 times for TR occurrence compared with the group 0 to 4-years of age. Presence of gingivitis in all index levels was related to an increased risk for TR. No relation was found between age or gingivitis index and lesion type. Mandibular third premolar and molar teeth were most commonly affected by TR, especially for type 1 lesions. Canine teeth were statistically more likely to have type 2 lesions. The trend for the canine teeth to be more affected with type 2 lesions needs further verification.

Xanthine urolithiasis causing bilateral ureteral obstruction in a 10-month-old cat

Xanthine urolithiasis was diagnosed in a 10-month-old intact female domestic shorthair cat presented with acute renal failure due to bilateral ureteral obstruction. Ultrasonography revealed the presence of multiple uroliths in both kidneys and ureters that were not detectable on previous survey radiographs. Medical management failed and ureteral obstruction persisted with no evidence of stone migration into the bladder. Bilateral ureterotomy with urolith removal was performed in order to relieve the obstruction. The cat recovered from surgery, and blood urea nitrogen and creatinine values decreased within normal limits 6 days postoperatively. Urolith analysis by infrared spectrometry determined xanthine composition, and a higher blood and urine concentration of hypoxanthine and xanthine was also found. At 1-year follow-up, the cat was free of clinical signs. However, ultrasonography of the abdomen revealed small-size calculi in both kidneys, despite the low protein diet intake. The very young age of the animal suggests a possible congenital xanthinuria.

Comparison of Histological and Proliferation Features of Canine Oral Squamous Cell Carcinoma Based on Intraoral Location: 36 Cases

Grade and labeling indices for immunohistochemical tumor proliferation markers Ki-67 and proliferating cell nuclear antigen (PCNA) were evaluated in 36 cases of canine oral squamous cell carcinoma (OSCC) based upon intraoral location. Grade was significantly associated with location (P = .035). Grade II tumors were most frequently diagnosed. Grade I tumors were identified in the gingiva and the buccal mucosa, and grade III tumors were seen in the gingiva and the tonsillar region. Animals with tumors arising from the tonsils and of the tongue tended to be older (P = .007), and those in the former group were more likely to have metastatic disease at the time of diagnosis (P = .001). Mean expression of PCNA and Ki-67 proliferation index (PI) for all tumors were 62.54% and 50.70%, respectively, and there was a statistical significant association between the 2 variables (R = .70; P < .001). Proliferation index was not associated with any of the intraoral locations evaluated, but higher PCNA PI was significantly associated with grade (P = .031). Ki-67 PI was significantly associated with lymph node metastasis at the time of diagnosis, especially for OSCC of gingival location (P = .028). The results obtained in this study are preliminary but clinically relevant, since they provide information that can explain differences in biologic behavior among intraoral locations and contribute to more accurate tumor staging to support the choice for different treatment strategies available for OSCC.

Oral and dental anomalies in purebred, brachycephalic Persian and Exotic cats

OBJECTIVE To determine the prevalence of dental anomalies in brachycephalic cats from various geographic regions and analyze potential relationships with oral disease. DESIGN Prospective multicenter cross-sectional study. ANIMALS 50 purebred Persian (n = 42) and Exotic (8) cats. PROCEDURES Cats were anesthetized, and a complete dental examination, dental charting, 3-view oral photography, and full-mouth dental radiography were performed. RESULTS Malocclusions were observed in 36 (72%) cats. Crowding of the teeth was evident in 28 (56%) cats, with the incisors being most commonly affected. Malpositioned teeth were noted in 32 (64%) cats, with abnormal orientation being the most common anomaly followed by rotation and impaction. Numerical abnormalities were present in 38 (76%) cats, including 6 (12%) with hyperdontia and 32 (64%) with hypodontia. Periodontal disease was reported in 44 (88%) cats, and cats with periodontal disease were older than cats without. Tooth resorption was evident in 35 (70%) cats. Overall, 123 of 1,349 (8.7%) teeth had external inflammatory resorption and 82 (6.1%) had external replacement resorption. The premolar teeth were the teeth most commonly affected with inflammatory resorption, whereas the canine teeth were the teeth most commonly affected with replacement resorption. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that because of their brachycephaly, Persian and Exotic cats have unique oral and dental features that may predispose them to dental disease (eg, tooth resorption and periodontal disease). Knowledge of the particular dental anomalies common in brachycephalic cats could aid in early detection and mitigation of dental disease in these breeds.

Superficial temporal myofascial flap application in temporomandibular joint arthroplasty in a cat

Case summary A 2-year-old, intact female domestic longhair cat was referred for surgical treatment after diagnosis of closed jaw locking secondarily to right temporomandibular joint ankylosis and left pseudoankylosis. The animal underwent successful surgical management with bilateral excision arthroplasty followed by interposition of a temporal superficial myofascial flap. Immediately after surgery, the full range of lower jaw movement was achieved and normal occlusion was maintained. Ankylosis did not recur in the 1 year postoperative follow-up period. Relevance and novel information A temporal myofascial flap could be considered as interposition material after temporomandibular joint arthroplasty to avoid postoperative re-ankylosis and mandibular drift. The main advantages of this flap are its autogenous origin, and the ability to maintain separation between the two bones, preserve mobility and disrupt new bone formation.

Parotid Salivary Duct Stenosis following Caudal Maxillectomy

Parotid salivary duct dilation was diagnosed in a 9-year-old male dog. The dog had undergone caudal maxillectomy on the ipsilateral side 2-years prior to presentation. Treatment consisted of parotid salivary duct excision and superficial parotidectomy that lead to the resolution of clinical signs. Transient facial neuropraxia was observed immediately after surgery and resolved spontaneously after 2-weeks. Parotid salivary duct dilation should be considered as a chronic postoperative complication following caudal maxillectomy.