Mammary gland tumors are the most common canine neoplasms. They account for 25–50% of all tumors diagnosed in bitches. Metastases and recurrences develop in about 35–70% of bitches following excision. The presence of regional lymph node metastases is a relevant factor affecting prognosis and treatment in cases of mammary gland tumors. The sentinel lymph node (SLN) is the first lymph node (or nodes) in the regional lymphatic basin that receives lymphatic flow from the primary neoplasm. The aim of this study is to investigate the SLN with indirect lymphography for a mammary tumor in dogs. The knowledge of the precise drainage pattern and SLN of the neoplastic mammary glands would provide clinically relevant information to the surgeon and to the oncologist, and it would be of high importance for the surgeon not only for performing the most adequate surgical excision but also for determining an accurate post-surgical prognosis.

Achilles tendon rupture in the dog is a common traumatic lesion. An accurate evaluation of etiology, grade of the lesion with or without loss of tendon substance, and time elapsed from the trauma can guide the surgeon in choosing the best surgical technique. Moreover, the healing process after a tendon injury is usually difficult and uncertain because the prognosis is influenced by extent of trauma, time elapsed between the trauma and its treatment and low tendon vascularization. However, the rapid development of tissue engineering and regenerative medicine could soon result in the development of scaffolds with bioactive proteins that can direct the healing process toward complete tendon regeneration without fibrotic tissue development.

Gastrointestinal tract tumours in dogs and cats are characterized by non-specific clinical presentation and laboratory abnormalities, but require fast identification, characterization and staging. Imaging techniques play a key role in the diagnostic process of these diseases in routine veterinary practice. Survey and contrast radiography may indicate primary or secondary signs of gastric or intestinal neoplasia such as a wall mass, functional alterations and stenosis points, but they have low sensibility and limited diagnostic value. Ultrasound allows to perform a detailed study of gastrointestinal wall's layers and thickness and adjacent organs but requires adequate acoustic windows and expert operators. Computed tomography is a reference technique both in human and veterinary oncology for the identification of primary neoplasms and for metastases searching thanks to the possibility to scan the whole body and the use of intravenous iodinated contrast medium for vascular assessment. Specific intraluminal distension techniques such as Helical-Hydro Computed Tomography and Computed Tomography Colonography can improve respectively stomach and colon associated masses. To date, Endoscopic Ultrasonography and Magnetic Resonance, despite their proven value in human medicine, lack of literatures that support their usefulness in the diagnosis and staging of gastrointestinal neoplasms in veterinary medicine and are not widely used in these pathologies. The purpose of this work is to review the literature on imaging modalities applied in gastrointestinal tumours diagnosis in dogs and cats, highlighting advantages and limitations of each technique in order to choose the proper imaging procedure in everyday clinical practice.

Mast cell tumour (MCT) is a common cutaneous and subcutaneous neoplasia in dogs. It can metastasise to lymph nodes (LNs), and this adversely affects the prognosis and treatment. The study aims to evaluate the SLN mapping of MCTs with radiographic indirect lymphography. Dogs that underwent clinical staging were prospectively enrolled. Lipiodol was injected around the MCT or the surgical scar. After 24 h, LNs that picked up contrast were radiographically assessed. Twenty-six dogs with 29 MCTs were included. MCTs were confirmed histologically, while SLNs were evaluated either by cytology and/or histology. SLNs were detectable in 23 dogs with 26 MCTs. Lymphatic vessels were visible in 19 MCTs. In nine MCTs, at least two SLNs picked up contrast. In particular, seven MCTs involved two SLNs, and two MCTs involved three different SLNs. In nine MCTs, at least a SLN was metastatic. This study indicates that the lymph drainage pattern of the MCTs may be different for each MCT, and more than one SLN can be involved. Indirect lymphangiography with Lipiodol allowed the detection of the SLN in 90% of MCTs. This provided clinically relevant information to remove the LN and stage the patient.

Alimentary lymphoma (AL) is the most common malignancy of the feline gastrointestinal tract and may cause variable mild to severe alteration of the gastric wall on ultrasonography (US) that can be very similar to those caused by inflammation (INF). The aim of this prospective study is to establish the value of B-mode and contrast-enhanced US (CEUS) in describing specific features of normal, inflammatory, and neoplastic gastric diseases in feline species. B-mode US and CEUS of the stomach were performed in anesthetized cats with or without gastric disorders. Gastric wall qualitative and quantitative parameters were evaluated on B-mode US and CEUS examination. A total of 29 cats were included: six healthy (HEA) cats as the control group; nine INF; three low-grade lymphoma (LGAL); 10 high-grade lymphoma (HGAL). On B-mode US, there were significant differences in thickness, the wall’s layer definition and echogenicity between HGAL and all the other groups (<0.001). For CEUS, statistical differences between groups were found in the following: HGAL vs. HEA, HGAL vs. INF; HGAL vs. LGAL; INF vs. HEA. Diagnostic accuracy (AUC) and cut-off value were calculated and found to be significant for thickness (3.8 mm) for INF vs. LGAL (AUC > 0.70) and “benign” vs. “malignant” (AUC > 0.90) as well as peak enhancement (34.87 dB) for “benign” vs. “malignant” (AUC > 0.70). INF and LGAL showed an overlap of qualitative and quantitative parameters both on B-mode and CEUS, while HGAL usually appears as a severe wall thickening with absent layer definition, high-contrast uptake, a specific enhancement pattern, regional lymphadenopathy and local steatitis. Thickness and peak enhancement can be useful parameters in the characterization of gastric infiltrates in cats.