Clinical Utility of Cytology from Preoperative Percutaneous Fine Needle Aspirates of Solitary Liver Masses in 220 Dogs: A Retrospective Study (2009-2019).

When a solitary liver mass is identified in a dog, a fine-needle aspirate (FNA) is commonly employed to attempt to obtain a diagnosis. Little information is provided in the literature evaluating the sensitivity/specificity of FNA cytology for solitary liver masses. We hypothesized that liver lesion size nor the presence of cavitation would impact the success of cytological diagnosis. Medical records were obtained for 220 client-owned dogs. Inclusion criteria included preoperative abdominal imaging, percutaneous FNA of a solitary hepatic mass with cytologic interpretation by a board-certified pathologist, and a surgical biopsy or mass excision yielding a histopathological diagnosis. Six dogs (2.7%) experienced a complication after FNA, none considered severe. The agreement rate for correct cytologic diagnosis was 22.9% (49/220). Of the neoplastic masses 18.9% (35/185) were correctly diagnosed via cytology. The overall sensitivity was 60%, and the specificity was 68.6%. Neither institution (P = 0.16), lesion size (P = 0.88), cavitation (P = 0.34), or needle gauge (P = 0.20) had an association with correct diagnosis. This study demonstrates that, although there is a low risk of complications following FNA of a hepatic mass, overall success rate for correct cytologic diagnosis based on FNA was low compared to histopathologic diagnosis.

Potential Seeding From Fine-Needle Aspiration of an Axial Osteosarcoma: A Case Report.

This report describes the first potential case of seeding after fine-needle aspiration (FNA) of a rib osteosarcoma in a dog. An 8-year-old, 28-kg female spayed Golden Retriever was presented to her primary veterinarian with a 3-week history of a 3-cm firm, unpainful, immobile mass arising from the 9th rib. The mass was aspirated and submitted for cytological examination. A subcutaneous nodule developed several days after the FNA was performed in a location immediately overlying but distinct from the primary rib tumor on palpation. Both the primary mass and the newly diagnosed subcutaneous nodule were biopsied and were consistent with an osteosarcoma. Although it cannot be ruled out that the subcutaneous lesion was metastatic, seeding was a reasonable explanation based on where the new mass was located and how quickly it appeared after the FNA was performed. The aim of this case report was to describe the possibility of tumor seeding during FNA for osteosarcoma. It is the authors' opinion that utility of cytological diagnosis of bone tumors outweighs the risk of possible seeding and should continue to be used as a routine diagnostic test for the diagnosis of aggressive bone lesions.

Effect of an intraoperative infusion of amino acids on body temperature, serum biochemistry, serum insulin and recovery variables in healthy dogs undergoing ovariohysterectomy.

Change in body temperature (BT), serum biochemistry and recovery variables were compared after infusion of amino acids (AA) or lactated Ringer's solution (LRS) in dogs undergoing ovariohysterectomy. Dogs received eight parts 10 per cent AA and two parts LRS (AA, n=10) or only LRS (CG, n=10) at 10 ml/kg/hour during 90 minutes of anaesthesia. BT was measured during anaesthesia and 60 minutes of recovery. Extubation time and shivering were noted. Serum samples were obtained before anaesthesia (T0), end of anaesthesia (T90) and 18 hours after (T18h). Friedman, Mann-Whitney, Kruskal-Wallis or Fisher's exact tests were used for analysis. A decrease in BT of -2.16 (-1.59 to -3.24)°C for group AA and -2.79 (-1.98 to -4.52)°C for group CG was different (P=0.02). Time to extubation was 5 (3-9) minutes for group AA and 9 (5-15) minutes for group CG and was different (P=0.01). Only 30 per cent of dogs in group AA and 100 per cent of dogs in group CG shivered during recovery (P=0.003). Glucose, insulin and blood urea nitrogen at T90 were higher than T0 and T18h for group AA. Dogs receiving intraoperative infusion of AA had a higher BT, extubated sooner and shivered less than control dogs at recovery from anaesthesia.

Use of PET/CT and Stereotactic Radiation Therapy for the Diagnosis and Treatment of Osteosarcoma Metastases.

This case report describes the use of two new concepts in the diagnosis and treatment of metastatic osteosarcoma (OSA) in one dog. The dog was initially presented for positron emission tomography and computed tomography (PET/CT) as full-body staging following amputation and adjuvant chemotherapy for treatment of OSA of the proximal tibia. The initial PET/CT did not show evidence of metastatic disease. Six mo after OSA, diagnosis pulmonary metastatic nodules were identified and oral toceranib phosphate was initiated. Twelve mo postdiagnosis the dog developed neck pain and non-ambulatory tetraparesis and was diagnosed with a C7 vertebral metastatic lesion based on magnetic resonance imaging. A second PET/CT was performed to screen for further metastatic lesions, and a nodule within the right ischium was identified. The C7 and ischial lesions were treated with stereotactic radiation therapy (SRT). Sixteen mo postdiagnosis, a third PET/CT was performed due to increasing size of the pulmonary nodules and a right-sided liver metastasis was detected. The liver mass was treated with SRT. The PET/CT scans facilitated identification of gross metastatic lesions that were subsequently treated with SRT, which resulted in clinical improvement of the dog's neurological signs.