Simonetta Citi

COX-2 expression in canine and feline invasive mammary carcinomas: correlation with clinicopathological features and prognostic for molecular markers.

SummaryCyclooxygenase (COX)-2 is an inducible enzyme linked to tumor growth and angiogenesis. Its expression occurs in a wide range of preneoplastic and neoplastic conditions in humans, including colon and breast carcinomas. We evaluated the role of COX-2 as a mediator of angiogenesis in feline and canine invasive carcinomas (IMCs) and its role as a prognostic indicator. COX-2 expression was assessed in neoplastic samples and healthy mammary glands by immunohistochemistry, and related to the following clinicopathological parameters: age, tumor size, histologic type, tumor grading, vessel invasion, estrogen (ER) and progesterone receptor (PR) status, Ki-67, HER-2 overexpression, microvessel density (MVD), VEGF expression and overall survival (OS). In both species, COX-2 immunoreactivity was not observed in healthy tissues, whereas 96% of feline and 100% of canine invasive carcinomas scored positive. In queens, COX-2 overexpression was significantly correlated to ER-negative status (p=0.04) and to increased PR (p=0.038) expression, and angiogenesis assessed by VEGF expression (p=0.002). In bitches an increased COX-2 expression was significantly correlated to HER-2 overexpression (p=0.013) and to tumor dedifferentiation (p=0.03). In both species increased levels of COX-2 were correlated to poorer prognosis (p=0.03 in dogs and p=0.002 in cats). COX-2 is expressed in mammary tissues during tumorigenesis and its expression is associated with a poorer prognosis in bitches and queens. The correlation of COX-2 expression and angiogenesis provides support for a potential role of COX-2 inhibitors for the prevention and the treatment of feline IMCs via their anti-angiogenic properties. In the canine species, moreover, COX-2 may be important for mediating HER-2 induced mammary tumors.

Overexpression of HER-2 in Feline Invasive Mammary Carcinomas: An Immunohistochemical Survey and Evaluation of Its Prognostic Potential

The role of c-erbB-2 protooncogene status in feline invasive mammary carcinomas (FMCs) was assessed through the HER-2 receptor immunohistochemical expression. The HER-2 overexpression was then correlated with some relevant histologic parameters and with the clinical course of the disease during a 2-year follow-up. Forty-seven FMCs from surgically treated queens were considered. Tumors were classified according to the WHO criteria and stromal or lymphatic invasion (or both) and histologic grading were recorded. The immunohistochemical staining was performed on paraffin sections and a well-defined scoring system based upon numbers of HER-2 receptors expressed on the cell surface was applied according to standard guidelines. Overall survival (OS) distributions were generated with the Kaplan-Meier method. HER-2 overexpression was detected in 28 of the 47 carcinomas (59.6%). This parameter was demonstrated to be significantly correlated with the shorter OS (P = 0.02). However, the HER-2 overexpression did not show significant correlation with histologic type, tumor grading, or presence of lymphatic invasion. Furthermore, the HER-2 overexpression appeared with a higher percentage in FMCs than what is reported in canine or human mammary carcinomas. The significant correlation with a shorter OS suggests a possible role of HER-2 as an additional marker of malignancy in FMCs and as a reliable prognostic indicator As in the human oncology practice, the identification of the FMCs that overexpress HER-2 may also promote new therapeutic strategies.

Expression of Vascular Endothelial Growth Factor in Canine Inflammatory and Non-inflammatory Mammary Carcinoma

Inflammatory mammary carcinoma (IMC) is the most aggressive type of mammary tumour in the dog and has been proposed as a model for human inflammatory breast cancer. The aim of this study was to investigate angiogenesis in canine IMC by immunohistochemical assessment of the expression of vascular endothelial growth factor (VEGF). Tissues from 19 cases of IMC were compared with tissues from 27 cases of invasive mammary carcinoma without inflammation (non-IMC). Immunohistochemical expression of oestrogen receptor (ER), progesterone receptor (PR) and HER-2 receptor was also assessed. VEGF was strongly expressed in all IMCs and the percentage of VEGF-immunoreactive tumour cells was significantly higher in IMC than in non-IMC (P=0.02). There was no difference in HER-2 receptor expression between IMC and non-IMC, and no IMC expressed ER or PR. These results suggest that VEGF may contribute to the high angiogenic phenotype of canine IMC and that this expression may underlie the tendency towards local and systemic metastasis of these tumours.

First-line metronomic chemotherapy in a metastatic model of spontaneous canine tumours: a pilot study

Metronomic chemotherapy—the low-dose, long term and frequently administered chemotherapy—has revealed in these years an important impact on the stabilization of cancer disease for its known antiangiogenic effects, prolonged clinical benefits and the improved quality of life of several cancer patients, without any high grade toxicity [1–3]. Both the low cost and the oral administration of the drugs are key characteristics of this schedule and may offer important social advantages [4]. Anecdotical case reports [5–7] and experiences in small subsets of patients enrolled in retrospective clinical studies [8–10] on metastatic cancers have been recently published about the use of metronomic therapy as a first-line treatment. These point out the possible importance of metronomic chemotherapy as an alternative approach to first-line therapy in frail patients requiring palliation or patients refusing the standard chemotherapy for its impact on the quality of life. However, no data of prospective clinical trials on first line metronomic chemotherapy are currently available in metastatic cancer human patients. The veterinary medical oncology has advanced dramatically over the past few decades, because of the successful application of a number of conventional chemotherapeutic drugs to the cancer conditions diagnosed in veterinary patients [11]. Veterinary oncology cases often present a unique opportunity to investigate novel drugs and treatment schedules providing many in vivo information to the larger medical community and giving new effective options for dogs themselves [12]. As well recently pointed out by Paoloni and Khanna [13], these studies may also have a great translational relevance, predicting new therapies and related surrogate markers in human beings because pet dogs with cancers might assist the transition between mouse models and human patients. Moreover, in the clinical practice, veterinarians and their clients are generally less willing to accept a high degree of side effects, which most often results in lower drug doses than the ones that are used in human oncology. The aim of the present pilot study was to test a first-line metronomic oral combination of cyclophosphamide (CTX) and celecoxib (CXB) in canine metastatic spontaneous tumours, characterizing possible biomarkers to translate in human clinical research.

COX-2, mPGES-1 and EP2 receptor immunohistochemical expression in canine and feline malignant mammary tumours

Prostaglandin (PG) signalling is involved in human and animal cancer development. PG E2 (PGE2 ) tumour-promoting activity has been confirmed and its production is controlled by Cyclooxygenase-2 (COX-2) and microsomal PGE synthase-1 (mPGES-1). Evidence suggests that mPGES-1 and COX-2 contribute to carcinogenesis through the EP2 receptor. The aim of our study was to detect by immunohistochemistry COX-2, mPGES-1 and EP2 receptor expression in canine (n = 46) and feline (n = 50) mammary tumours and in mammary non-neoplastic tissues. COX-2 positivity was observed in 83% canine and 81% feline mammary carcinomas, mPGES-1 in 75% canine and 66% feline mammary carcinomas and the EP2 receptor expression was observed in 89% canine and 54% feline carcinomas. The frequency of COX-2, EP2 receptor and mPGES-1 expression was significantly higher in carcinomas than in non-neoplastic tissues and adenomas. COX-2, mPGES-1 and EP2 receptor expression was strongly associated. These findings support a role of the COX-2/PGE2 pathway in the pathogenesis of these tumours.

Peripheral nerve stimulation under ultrasonographic control to determine the needle-to-nerve relationship

OBJECTIVE To determine the needle-to-nerve distances during electrical nerve location in dogs at different currents and pulse duration using a peripheral nerve stimulator (PNS) under ultrasound control (US), and the minimal electrical thresholds (MET) necessary to obtain a motor response (MR) after achieving needle-to-nerve contact. STUDY DESIGN Prospective in vivo experimental trial in a clinical setting ANIMALS Thirty dogs, scheduled for locoregional anaesthesia of the sciatic nerve. METHODS Needle-to-nerve distance was measured ultrasonographically after obtaining the MR of sciatic nerve with 2, 1 and 0.5 mA and pulse duration 0.1 ms (NS0.1). Thereafter the needle was placed in contact with the nerve and MET was determined. The procedure was repeated with 0.3 ms (NS0.3). Finally the needle was reintroduced to contact the sciatic nerve guided only by US, thus MET-US was determined. Data were analysed using Kruskal-Wallis or Mann-Whitney tests. RESULTS Needle-to-nerve distances were greater when MR was obtained with 2 mA than with 1 and 0.5 mA at 0.1 and 0.3 ms. No significant differences were observed between the needle-to-nerve distances using 0.1 or 0.3 ms. The MET [median (range)] was 0.4 (0.18-1.3) mA in NS0.1, 0.32 (0.12-0.8) mA in NS0.3; while MET-US was 0.7 (0.32-1.5) mA. When the needle contacted the nerve, the MR achieved with currents below 0.3 mA was obtained in 17.2, 40 and 0% of cases using NS0.1, NS0.3 and US respectively. CONCLUSIONS AND CLINICAL RELEVANCE The electrical current necessary to obtain a MR decreased as the needle moved towards the nerve. However when the needle tip contacted the nerve, an MR with low current intensity could not be obtained. Thus the absence of motor response at currents below 0.3 mA cannot rule out needle-epineurium contact. When ultrasound is combined with PNS, it is more important to assess the correct needle position than searching for an MR at low currents.

Spectral waveform analysis of intranodal arterial blood flow in abnormally large superficial lymph nodes in dogs

OBJECTIVE To evaluate pulsed-wave Doppler spectral parameters as a method for distinguishing between neoplastic and inflammatory peripheral lymphadenopathy in dogs. SAMPLE POPULATION 40 superficial lymph nodes from 33 dogs with peripheral lymphadenopathy. PROCEDURES 3 Doppler spectral tracings were recorded from each node. Spectral Doppler analysis including assessment of the resistive index, peak systolic velocity-to-end diastolic velocity (S:D) ratio, diastolic notch velocity-to-peak systolic velocity (N:S) ratio, and end diastolic velocity-to-diastolic notch velocity ratio was performed for each tracing. Several calculation methods were used to determine the Doppler indices for each lymph node. After the ultrasonographic examination, fine needle aspirates or excisional biopsy specimens of the examined lymph nodes were obtained, and lymphadenopathy was classified as either inflammatory or neoplastic (lymphomatous or metastatic) via cytologic or histologic examination. Results of Doppler analysis were compared with cytologic or histopathologic findings. RESULTS The Doppler index with the highest diagnostic accuracy was the S:D ratio calculated from the first recorded tracing; a cutoff value of 3.22 yielded sensitivity of 91%, specificity of 100%, and negative predictive value of 89% for detection of neoplasia. Overall diagnostic accuracy was 95%. At a sensitivity of 100%, the most accurate index was the N:S ratio calculated from the first recorded tracing; a cutoff value of 0.45 yielded specificity of 67%, positive predictive value of 81%, and overall diagnostic accuracy of 86.5%. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that noninvasive Doppler spectral analysis may be useful in the diagnosis of neoplastic versus inflammatory peripheral lymphadenopathy in dogs.

MICRONODULAR ULTRASOUND LESIONS IN THE COLONIC SUBMUCOSA OF 42 DOGS AND 14 CATS

Micronodular ultrasound lesions have been detected in the colonic submucosa of dogs and cats at our hospital. The lesions had rounded/oval shapes, measured 1-3 mm in size, and exhibited a hypo/anechoic ultrasonographic pattern. To our knowledge, these lesions have not been previously reported in human or veterinary patients. The purpose of this retrospective study was to determine whether micronodular lesions were associated with other abdominal ultrasound abnormalities or clinical findings. Medical records of dogs and cats with sonographic reports describing micronodular lesions within the colonic submucosa were reviewed. Concurrent ultrasonographic abnormalities were recorded and compared with clinical sidgns and follow-up data. A total of 42 dogs and 14 cats met inclusion criteria. Concurrent sonographic abnormalities included the following: increased colon wall thickness (12.5%); small bowel wall thickening, altered layering, and/or hyperechoic mucosa (45%); abdominal effusion (29%); caudal mesenteric lymphadenopathy (46%); mesenteric lymphadenopathy (27%); and pericolic peritoneal fat reactivity (9%). Fifty of 56 animals presented with diarrhea. Twenty-seven cases had clinical signs of colitis and ultrasonographic lesions were limited to the colonic submucosa. In nine cases, follow-up examination at 6-8 weeks showed resolution of clinical and ultrasonographic signs. Ultrasonographic and clinical examinations in 17 patients at 12-18 months and in 20 patients at 18-30 months from initial diagnosis showed resolution of submucosal lesions and clinical signs of enteropathy. The authors propose that micronodular submucosal ultrasound lesions may represent reactive intraparietal lymphoid follicles and may be indicators of colonic inflammatory diseases in dogs and cats.

Ultrasonography Appearance of the Equine Proximal Palmar Metacarpal Region After Local Anesthetic Infiltration

Abstract Suspensory ligament (SL) disease is a common source of lameness in the horse. Once injury of the proximal SL is suspected, based on the clinical examination and response to analgesia, diagnostic imaging of the region is often performed. The aim was to describe the presence of ultrasonographic artifacts in the palmar metacarpal area after 20 minutes and at 24 hours after infiltration of local anesthetic solution using the lateral approach. In the present study, SL and other proximal palmar metacarpal structures were ultrasonographically evaluated before and after perineural injection of mepivacaine 2% in eight forelimbs of four horses. The limbs were divided into two groups: group 1: needle not filled with anesthetic (right forelimbs); group 2: needle filled with anesthetic (left forelimbs). The ultrasonographic examination of the palmar metacarpal structures was performed after 20 minutes and at 24 hours after injection to evaluate qualitative postinjection changes and to perform measures. In the present study, there were no significant differences in the SL and other palmar metacarpal structures between baseline measurement and pattern and postinjection measurements. No changes in echogenicity or fiber pattern of the tendons and ligaments were found. Alterations consistent with gas echoes were detected in one limb in group 1 at 20 minutes after injection, whereas no gas patterns were visualized at 24 hours. Gas or fluid artifacts, due to local anesthetic infiltration, may be present. This suggests that diagnostic ultrasonography of the origin of the SL should be interpreted with caution if performed within 24 hours after diagnostic analgesia. HighlightsNo differences in measures related to time were found in both groups.No changes in echogenicity or fiber pattern of the tendons and ligaments were seen.Gas echoes were seen in one limb injected with an empty needle.

Renal Measures in Healthy Italian Trotter Foals and Correlation Between Renal and Biometric Measures: Preliminary Study

Abstract The aim of this study was to evaluate ultrasonographic renal measures in healthy foals aged 1–6 weeks and to verify the correlation between biometric measures to ultrasonographic renal ones. A total of nine Italian trotter foals born in the same stud farm and underwent similar management conditions were enrolled. Inclusion criteria were normal gestation time, unassisted delivery, and normal physical examination at all evaluation times. Length and height of both kidneys were measured by ultrasound weekly from 1 to 6 weeks of life, along with the thoracic and the middle third of the metacarpal area circumferences. Data were expressed as mean and standard deviation, and distribution was evaluated. One‐way analysis of variance (ANOVA) was applied to verify differences related to time. The Pearson correlation test was carried out to evaluate the linearity between time versus all the parameters measured. Students t test was used to verify differences in ultrasound measures between right and left kidney at all recorded times. The Pearson test was applied to a mean‐variance matrix to verify the correlation between each biometrical versus all renal measures. Significance level was set at P < .05. One‐way ANOVA showed differences in biometric and renal measures related to time. Correlation test revealed a linear growth. Differences in ultrasound renal measures between right and left kidney were obtained. Correlation was found between biometrical parameters versus kidney measures. Renal measures and differences between left and right kidneys were in line with literature. Correlation test revealed a linear growth. Renal growth is correlated with age and biometric measures.