Evaluation of lung lobectomy and adjuvant treatment for primary pulmonary carcinoma in dogs: 89 cases (2005-2022)

OBJECTIVES

Primary lung cancer is relatively common in dogs. Despite the existing literature on long-term follow-up and outcome, further clinical studies focusing on a single histotype are needed, specifically about epithelial tumours since they are the ones most frequently detected.

MATERIALS AND METHODS

The medical records of four European institutions were reviewed to identify dogs undergoing lung lobectomy for a primary lung carcinoma between 2005 and 2022.

RESULTS

A total of 89 dogs were included. Median age was 11 years (range 5 to 17 years) and median body weight was 23 kg (range 2.5 to 47 kg). Overall median survival time was 252 days (range 6 to 1558 days) and overall progression-free interval was 140 days (range 7 to 684 days). The 1-, 2- and 3-year survival rates were 61%, 47% and 30%, respectively. Presence of clinical signs at presentation, pleural effusion, completeness of surgical margins, histopathological features and use of adjuvant chemotherapy did not influence survival. Patients with maximum tumour diameter ≥ 5 cm had a reduced survival compared to patients with smaller tumours (median survival time 284 days vs. 717 days, 95% CI 8 to 719), and dogs with histologically confirmed lymph node metastasis had a reduced survival compared to patients with no evidence of local metastasis (median survival time 162 days vs. 614 days, 95% CI 39 to 760). None of the other assessed variables influenced progression-free interval.

CLINICAL SIGNIFICANCE

Dogs with primary pulmonary carcinoma with no lymph node involvement and with a maximum tumour diameter of < 5 cm may have a better prognosis and prolonged survival. Further studies are needed to elucidate the role of adjuvant chemotherapy in case of clinically aggressive lung cancer.

Acute and chronic systemic inflammation associated with canine nodular splenic lesions composed of heterogeneous cell components: four cases (2020-2024)

OBJECTIVES

To describe the clinical presentation and clinicopathological findings of dogs with nodular splenic lesions composed of heterogeneous cell components associated with systemic inflammation and to provide information on the outcome after surgical resection.

MATERIALS AND METHODS

Medical records were searched for dogs with histologically and immunohistochemically characterised nodular splenic lesions with mixed stromal, histiocytic and lymphoid cells and the presence of systemic inflammatory markers at the time of diagnosis.

RESULTS

Four dogs were included, of which three had an undifferentiated splenic stromal sarcoma and one had a splenic leiomyosarcoma. Fever and abdominal pain were reported in three and four cases, respectively. All dogs showed hyperglobulinaemia and marked changes in the serum protein electrophoresis profile. C-reactive protein and fibrinogen concentrations were both increased in three cases. These abnormalities completely resolved after splenectomy. Moreover, two dogs had concomitant glomerular disease and one dog had liver amyloidosis. Three dogs were still alive and asymptomatic 1, 6 and 9 months after surgery. One dog died 16 months after the initial presentation due to complications related to progressive renal failure.

CLINICAL SIGNIFICANCE

Based on this report, nodular splenic lesions with heterogeneous cell components may directly be associated with a pro-inflammatory state and should be considered as part of the differential diagnosis of fever and hyperglobulinaemia in dogs. Furthermore, early recognition and treatment of these lesions could reduce the risk of systemic complications potentially associated with amyloid deposit and organ failure.

Canine lung carcinoma-A descriptive review

Primary lung cancer is a relatively uncommon tumor in dogs, accounting for about 1% of all canine malignancies. Clinical signs in affected dogs can range from being asymptomatic to exhibiting chronic cough, and in rare cases, dyspnoea. Surgical excision of the primary tumor, along with resection of the affected locoregional lymph nodes is the preferred treatment option for most cases. Although chemotherapy, targeted therapy and radiation therapy have been employed, their effectiveness remain controversial. Dogs with stage T1 tumors can experience extended survival times of up to 2 years. However, the prognosis for dogs with advanced metastatic tumors is generally very poor. This review article discusses the etiology, clinical signs, diagnosis, staging, treatment options, and prognosis of primary lung carcinoma in dogs.

Computed tomography scan accuracy for the prediction of lobe and division of liver tumors by four board-certified radiologists

OBJECTIVE

(1) Evaluate the accuracy of computed tomography (CT) scans for localization of liver masses. (2) Assess the agreement between radiologists on localization. (3) Determine if location influences the accuracy of localization and histopathologic diagnosis. (4) Determine what lobar vasculature radiologists found most useful for localization.

STUDY DESIGN

Retrospective.

ANIMALS

A total of 67 client-owned dogs with a total of 75 hepatic masses.

METHODS

Records were reviewed for relevant data. Localization for each hepatic mass was performed by four radiologists (JH, EH, ML, JF) independently.

RESULTS

Overall accuracy of mass localization was 217/292 (74.3%) by lobe and 264/300 (88%) by division. Accuracy for the quadrate lobe (11/27, 40.7%) was lower (p < .05) than for the caudate process of the caudate lobe (19/24, 79.2%), left medial lobe (47/64, 73.4%) and left lateral lobe (95/101, 89.6%). Accuracy for the right lateral lobe (17/35, 48.6%) was lower (p < .05) lower than for the left lateral lobe (95/101, 89.6%). Accuracy of localization was 173/192 (90.1%) for masses located in the left division, 37/48 (77.1%) in the central division, and 53/60 (88.3%) for the right division. The agreement (kappa) between radiologists was good (0.61-0.8) to excellent (0.81-1) for division and moderate (0.41-0.6) to good for lobe localization.

CONCLUSION

CT localization was more accurate for division than lobe localization of canine hepatic masses. Similarly, radiologists had a better agreement for division than lobe localization.

CLINICAL SIGNIFICANCE

This study supports CT as a useful modality for liver mass localization based on division. CT localization to specific lobes should be interpreted with some caution.

An Abscopal Effect on Lung Metastases in Canine Mammary Cancer Patients Induced by Neoadjuvant Intratumoral Immunotherapy with Cowpea Mosaic Virus Nanoparticles and Anti-Canine PD-1

Neoadjuvant intratumoral (IT) therapy could amplify the weak responses to checkpoint blockade therapy observed in breast cancer (BC). In this study, we administered neoadjuvant IT anti-canine PD-1 therapy (IT acPD-1) alone or combined with IT cowpea mosaic virus therapy (IT CPMV/acPD-1) to companion dogs diagnosed with canine mammary cancer (CMC), a spontaneous tumor resembling human BC. CMC patients treated weekly with acPD-1 (n = 3) or CPMV/acPD-1 (n = 3) for four weeks or with CPMV/acPD-1 (n = 3 patients not candidates for surgery) for up to 11 weeks did not experience immune-related adverse events. We found that acPD-1 and CPMV/acPD-1 injections resulted in tumor control and a reduction in injected tumors in all patients and in noninjected tumors located in the ipsilateral and contralateral mammary chains of treated dogs. In two metastatic CMC patients, CPMV/acPD-1 treatments resulted in the control and reduction of established lung metastases. CPMV/acPD-1 treatments were associated with altered gene expression related to TLR1-4 signaling and complement pathways. These novel therapies could be effective for CMC patients. Owing to the extensive similarities between CMC and human BC, IT CPMV combined with approved anti-PD-1 therapies could be a novel and effective immunotherapy to treat local BC and suppress metastatic BC.

Rhabdomyosarcoma in a Rabbit

A geriatric Holland Lop rabbit presented for acute lameness. A pathologic fracture of the right distal femur associated with a pleomorphic rhabdomyosarcoma was diagnosed, and staging radiographs showed no overt metastasis upon initial presentation. The limb was amputated and submitted for microscopic examination. Immunohistochemical evaluation revealed the neoplastic cells were positive for desmin and MyoD1, and negative for cytokeratin AE1/AE3, CD204, IBA-1, and SMA. Gross, histologic, and immunohistochemical evaluation confirmed a diagnosis of pleomorphic rhabdomyosarcoma. The patient died 396 days after amputation, and a post-mortem examination showed metastatic sarcoma to multiple organs.

Characterization of alkaline phosphatase cytochemistry in canine neoplastic and non-neoplastic pulmonary mass aspirates

BACKGROUND

Distinguishing primary and secondary pulmonary neoplasms can be challenging via cytology, and a rapid, inexpensive diagnostic tool to differentiate these neoplasms is unavailable. Alkaline phosphatase cytochemistry (ALP-CC) has been used to identify primary pulmonary carcinomas in human patients, and we hypothesized it could be applied to canine lung aspirates.

OBJECTIVE

We aimed to characterize ALP-CC expression in fine-needle aspirate (FNA) samples of canine pulmonary neoplastic and non-neoplastic tumors.

METHODS

A retrospective case search was conducted to identify cases with contemporaneous cytology and histopathology reports from pulmonary lesions, including neoplastic and non-neoplastic etiologies. Slides prepared from pulmonary aspirates were stained for ALP-CC activity, and the percentage of ALP-CC-positive primary pulmonary epithelial tumors was determined. To characterize the ALP-CC expression in non-neoplastic cellular constituents of pulmonary FNA samples, mesothelial cells were also evaluated.

RESULTS

Forty-eight canine cases met the inclusion criteria. ALP-CC-positive cells were seen in both neoplastic and non-neoplastic lesions. In non-neoplastic lesions, pulmonary epithelial cells were ALP-CC positive. Eighty-nine percent of primary pulmonary epithelial neoplasms were ALP-CC positive, and no ALP-CC positivity was noted in mesothelial cells. ALP-CC-positive neoplastic cells were seen in a metastatic amelanotic melanoma.

CONCLUSIONS

Primary pulmonary epithelial neoplasms are frequently ALP-CC positive, but such positivity is not restricted to this tumor type. Non-neoplastic pulmonary epithelial cells can be ALP-CC positive, whereas mesothelial cells are negative.

Thoracic Tumor Associated with a Unilateral Empyema in a Beef Cow: A Case Report

Tumors in cows are not frequently reported in the literature. They often represent unusual findings in live animals and are incidental at slaughter with rare positive therapeutic outcomes for farmers. A 9-year-old beef cow was referred to the hospital of ruminants of the National Veterinary School of Toulouse, France. The cow started to become sick 10 days prior, and major symptoms were anorexia, arched back, tachycardia, and tachypnea associated with significantly attenuated cardiac and pulmonary sounds upon right-sided auscultation. After specific investigations, a thoracic sarcoma associated with unilateral empyema was diagnosed. The empyema was treated, and supportive treatment was only performed for the tumor. Although the sarcoma remained, clinical improvement was significant, and the cow went back to her farm of origin. After the end of the withdrawal period, the cow recovered clinically but was culled by the owners for economic reasons. The present case report offers a continuum from the initial clinical signs motivating specific investigations to interesting laboratory findings, which were confirmed post-mortem.

Echocardiographic, thoracic ultrasonographic, and CTA diagnosis of pericardial neoplasia in a dog

A 12-year-old male neutered Yorkshire Terrier presented for coughing and respiratory distress. Transthoracic echocardiography initially misdiagnosed the patient with pericardial effusion; repeat echocardiography increased suspicion for neoplasia. A definitive diagnosis was not apparent. Findings on thoracic computed tomography and thoracic ultrasound were consistent with a diffusely thickened, heterogenous, hypoechoic soft tissue structure surrounding the heart. Fine needle aspirates were obtained using ultrasound guidance and routine cytology of the intrapericardial mass was consistent with neoplasia, with pericardial mesothelioma most likely. These novel findings highlight the importance of thoracic ultrasound and potential limitations of echocardiography in diagnosis of pericardial neoplasia.

Prevalence of lung atelectasis in sedated dogs examined with computed tomography

Background

Computed tomography (CT) scanning of the lung is known to be a valuable tool when investigating lung pathology of the dog. During CT-scan the dog needs to be immobilized and general anesthesia has historically been considered as gold standard although being a more expensive and time-consuming alternative to sedation. Today, modern high speed multidetector CT-scanners offer new possibilities for sedation as an alternative. Both anesthesia and sedation can cause lung atelectasis, and this can be problematic when reading the CT-images since it potentially can masque or mimic lung pathology leading to misdiagnosis. The objective of this prospective analytic study was to investigate the prevalence of lung atelectasis and changes in lung attenuation over time in dogs that receive intravenous sedation and positioned in sternal recumbency.

Results

20 dogs without known lung pathology underwent three consecutive CT-scans of the lung; the first scan was initiated as soon as the dog was sufficiently sedated, the second scan approximately 5 min after the first one and the last scan after the dog’s orthopaedic scan was completed. The dogs received intravenous sedation in a combination of dexmedetomidine and butorphanol and were kept positioned in a strict sternal recumbency during sedation and exam. Each lung lobe was individually examined in an axial plane and measurements of dorsal, ventral, and mean lung attenuation were made. Atelectasis or areas with poorly aerated lung tissue were not detected as all parts of the lobes were normally aerated at all three scans. A statistically significant increase in lung attenuation between the first and the second scan (P = 0.03) and between the first and the third scan (P = 0.0004) was seen in the ventral part of the lobes.

Conclusions

This study indicates that CT-examination of the lungs can be performed on sedated dogs that are kept in a sternal recumbency without development of atelectasis. It also suggests that there is an early correlation between time and increase in lung attenuation.

Imaging and endoscopic diagnosis of lung diseases in small animals. A review

Diagnostic imaging plays a fundamental role in the diagnosis of pulmonary diseases. Radiography, ultrasound, computed tomography, and endoscopy are important tools for achieving a diagnosis. The choice of diagnostic procedure varies according to the patient, the suspected diagnosis and the risk/benefit ratio. Culture, cytology and histology are nearly always necessary to obtain a definitive diagnosis. Several biopsy sampling techniques are described. Surgical biopsies are the gold standard for the diagnosis of bronchiolitis or interstitial lung diseases but often not performed due to the high risk. In humans, the introduction of transbronchial cryobiopsies has led to excellent results in the study of interstitial lung diseases.

Proteomic Assessment of Extracellular Vesicles from Canine Tissue Explants as a Pipeline to Identify Molecular Targets in Osteosarcoma: PSMD14/Rpn11 as a Proof of Principle

Osteosarcoma (OS) is a highly malignant bone tumour that has seen little improvement in treatment modalities in the past 30 years. Understanding what molecules contribute to OS biology could aid in the discovery of novel therapies. Extracellular vesicles (EVs) serve as a mode of cell-to-cell communication and have the potential to uncover novel protein signatures. In our research, we developed a novel pipeline to isolate, characterize, and profile EVs from normal bone and osteosarcoma tissue explants from canine OS patients. Proteomic analysis of vesicle preparations revealed a protein signature related to protein metabolism. One molecule of interest, PSMD14/Rpn11, was explored further given its prognostic potential in human and canine OS, and its targetability with the drug capzimin. In vitro experiments demonstrated that capzimin induces apoptosis and reduces clonogenic survival, proliferation, and migration in two metastatic canine OS cell lines. Capzimin also reduces the viability of metastatic human OS cells cultured under 3D conditions that mimic the growth of OS cells at secondary sites. This unique pipeline can improve our understanding of OS biology and identify new prognostic markers and molecular targets for both canine and human OS patients.

Suspected Primary Spontaneous Asymptomatic Pneumothorax in a Cat

Spontaneous pneumothorax (SPT) is a documented emergency of the respiratory tract condition classified as either primary or secondary based on the presence of underlying pulmonary conditions. All reported SPT in the feline literature are evaluated for respiratory clinical signs. Primary SPT without underlying pathology or without clinical signs is not reported in cats. This case report describes a 10-year-old domestic longhair cat that was referred for evaluation of chronic lethargy with severe azotemia and placement of a subcutaneous ureteral bypass (SUB) system. Prior to presentation, the cat was diagnosed with renal insufficiency and treated medically with no resolution. Clinical examination under sedation revealed right-sided renomegaly. Thoracic radiographs revealed gas in the caudodorsal pleural space and concurrent pulmonary atelectasis. No respiratory clinical signs were present. Thoracic CT showed two pulmonary bullae, one located in the right caudal lung lobe and one in the cranial segment of the left cranial lung lobe. Abdominal ultrasound showed a right-sided ureteral obstruction. Medical management was elected for the spontaneous pneumothorax. A SUB was placed to address the ureteral obstruction; no complications were noted during recovery. The cat was free of clinical signs of respiratory disease after a follow-up time of nine months. This is the first reported case of a cat diagnosed with a nonclinical suspected primary spontaneous pneumothorax with no concurrent predisposing pulmonary pathology.

Oral and Maxillofacial Tumor Management - From Biopsy to Surgical Removal

The main objective of oral and maxillofacial (OMF) tumor resection is to get local control of the disease. Many OMF tumors can be cured with wide or radical surgery, whereas others might only achieve temporary local control of the disease by removing infection and the source of pain, thereby improving the quality of life of the patient while keeping masticatory function. The standard of care on managing OMF tumors includes the diagnosis and identification of the local and distant extension of the disease to establish an appropriate treatment plan tailored for each patient. In this article, we provide a practical review of the current information related to staging, biopsy, and main surgical techniques for OMF tumor removal.

Outcomes and Blood Product Use in 89 Surgically Managed and 79 Medically Managed Cases of Acute Spontaneous Hemoperitoneum in the Dog

Objective: To describe a population of dogs with acute spontaneous hemoperitoneum (ASH) that were treated with either surgical or medical management in the first 12 h after presentation, and to perform a preliminary investigation into whether there were differences in achieving cardiovascular stabilization or patterns of red blood cell (RBC) transfusion between patients treated with early (<12 h) surgery vs.medical management. Design: A retrospective multicenter preliminary study performed on 168 dogs presenting with ASH between January 2015 and May 2019. Patients were excluded if they were euthanized or discharged from hospital within the first 12 h, or if clinical records were incomplete. All patients received appropriate medical stabilization efforts. Statistical analysis was performed comparing patients that underwent early (<12 h) surgery and those that did not. Results: Eighty-nine patients were in the early surgical group and 79 patients in the medical group. A significantly higher proportion of medical cases were euthanized (p < 0.001). A significantly higher proportion of early surgical cases were discharged from hospital (p = 0.005). There was no statistically significant difference between groups in achieving cardiovascular stabilization (OR 1.07 p = 0.82). A higher proportion of patients with body-weight over 20 kg achieved stabilization within 12 h than those with body-weight of 20 kg or less (62.7 vs. 41.4%, p < 0.01). A higher proportion of patients with splenic conditions achieved stabilization than patients with non-splenic conditions (56.5 vs. 28.6%, p = 0.05). The odds of receiving an RBC transfusion were higher in the early surgical group than the medical group [OR 3.81 (p < 0.001)]. Conclusions: This preliminary study did not identify a significant difference in the ability to achieve cardiovascular stabilization in the first 12 h in dogs with ASH that underwent early surgical intervention vs. those managed medically. Patients in the early surgical group were more likely to receive a RBC transfusion than those in the medical group. At this time the decision on whether to pursue medical or early surgical management should be made on a case by case basis.

Tolerability and outcome of palliative treatment for metastatic pulmonary carcinoma in cats

OBJECTIVES

Pulmonary carcinoma is uncommon in cats and reporting of outcomes following medical treatment is limited, especially in presence of metastases. The aim of this study was to describe the outcome of cats affected by metastatic primary pulmonary carcinoma and to evaluate the tolerability of palliative treatment in this patient population.

MATERIALS AND METHODS

Medical records were searched for cats with a cytological or histopathological diagnosis of primary pulmonary carcinoma and evidence of metastatic disease. Cats were treated with antineoplastic agents, corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs) or received no systemic treatment. Cases in which thoracic CT was not performed, and those lacking definitive diagnosis by cytology or histopathology or receiving curative-intent surgery were excluded.

RESULTS

Thirty-four cats were identified: 18 were treated with antineoplastic agents and 16 received corticosteroids, NSAIDs or no treatment. Presenting clinical signs included coughing (53%), tachypnoea (26%), gastrointestinal signs (35%) and lethargy (18%). CT scan identified metastases to the lung parenchyma in all cases and additional metastatic lesions in 10 of 34 (59%) cases; pleural effusion was detected in 11 cases (32%). The overall median survival time for all cats was 64 days [range 1-1352 days; 95% confidence interval (CI) 48-164]. Presence of respiratory signs at presentation was the only factor influencing survival in the multivariable analysis.

CLINICAL SIGNIFICANCE

Medical treatment was well tolerated and appeared to palliate clinical signs in cats with metastatic pulmonary carcinoma, albeit with a modest duration and short overall survival. The role and benefit of chemotherapy/antineoplastic agents versus conventional palliative drugs in this setting remains unclear.

Lung ultrasound nodule sign for detection of pulmonary nodule lesions in dogs: Comparison to thoracic radiography using computed tomography as the criterion standard

Thoracic radiography (TR), the most common screening test for pulmonary metastases in dogs, can fail to detect small lesions <3 mm. Lung ultrasonography (LUS) is a widely available imaging modality capable of detecting peripheral nodules but is underutilized for this purpose. Thoracic computed tomography (CT) is the criterion standard for diagnosis of lung metastases and nodular disease but is less practical for a variety of reasons. We hypothesized that LUS would be more sensitive but less specific at detecting nodules consistent with metastatic pulmonary disease in dogs compared to TR, using CT as the criterion standard. This was a masked, single-center prospective study of 62 client-owned dogs evaluated for respiratory signs or pulmonary metastatic neoplasia screening using TR, LUS and CT. Dogs were included if metastatic pulmonary disease was a differential. All imaging modalities were scored as having nodules (yes/no) and other types of pathologic lesions were recorded. Sensitivity (Se), specificity (Sp) and positive (LR+) and negative likelihood ratios (LR-) were determined for TR and LUS. For TR, Se and Sp were 64% and 73%, and LR+ and LR- were 2.37 and 0.49, respectively. For LUS, Se and Sp were 60% and 65% and LR+ and LR- were 1.71 and 0.62, respectively. The results of the study indicate that LUS had a similar Se to TR, with both modalities missing nodules when used for screening. The low Sp and LR- suggests caution should be used when assuming TR and LUS rule out the presence of nodules.

Do All Roads Lead to Rome? The Potential of Different Approaches to Diagnose Aelurostrongylus abstrusus Infection in Cats

An infection with the cat lungworm, Aelurostrongylus abstrusus, can be subclinical, but it can also cause severe respiratory clinical signs. Larvae excretion, antibody levels, clinical assessment findings of the respiratory system and diagnostic imaging findings were recorded and compared for six cats with experimental aelurostrongylosis. In five cats, patency started 33-47 days post infection (pi), but two cats excreted larvae only in long intervals and low numbers. Positive ELISA results were observed in four cats with patent aelurostrongylosis, starting between five days before and 85 days after onset of patency. One seropositive cat remained copromicroscopically negative. Mild respiratory signs were observed in all cats examined. A computed tomographic (CT) examination of the lungs displayed distinct alterations, even in absence of evident clinical signs or when larvae excretion was low or negative. The thoracic radiograph evaluation correlated with the CT results, but CT was more distinctive. After anthelmintic treatment in the 25th week post infection, pulmonary imaging findings improved back to normal within 6-24 weeks. This study shows that a multifaceted approach, including diagnostic imaging, can provide a clearer diagnosis and monitoring of disease progression. Furthermore, a CT examination provides an alternative to post mortem examination and worm counts in anthelmintic efficacy studies.

[Intrapelvic leiomyoma causing concurrent colonic and urethral obstruction in a dog]

An 8-year-old female spayed dog was presented due to simultaneous inability to defecate and urinate. During digital rectal examination a smooth, rounded, firm-elastic mass was detected. Laboratory results showed a 6-fold elevation of serum lactate dehydrogenase activity. Ultrasonographic, radiographic and computed tomography findings raised the suspicion of a leiomyoma. An ultrasound-guided fine needle aspiration biopsy was performed under mild sedation but cytologic evaluation was inconclusive. During laparotomy the mass was located at the colorectal transition. It was completely removed while keeping the intestinal wall intact. The results of the histopathological examination and immunohistochemistry confirmed the initial tentative diagnosis of a leiomyoma. Postoperatively the patient was able to pass urine and feces spontaneously. Six months later the dog presented clinically unremarkable. Abdominal ultrasound and rectal examination exhibited no signs of recurrence. Lactate dehydrogenase activity was only marginally increased.

Prevalence of pulmonary nodules suggestive of metastasis at presentation in dogs with cutaneous or subcutaneous soft tissue sarcoma

OBJECTIVE

To investigate the prevalence of pulmonary nodules suggestive of metastasis at the time of initial presentation in dogs with cutaneous or subcutaneous soft tissue sarcomas (STSs) and no previous related thoracic diagnostic imaging.

ANIMALS

146 client-owned dogs with a cutaneous or subcutaneous STS.

PROCEDURES

Medical records were retrospectively searched to identify dogs with STSs that underwent initial thoracic diagnostic imaging when presented for referral examination between September 2014 and March 2018. Data collected included patient and tumor characteristics. Results were evaluated for dogs grouped on the basis of variables of interest (eg, STS grade, duration, or history).

RESULTS

Initial thoracic imaging was performed with CT (131/146 [89.7%]) or radiography (15 [10.3%]). Although the presence or absence of pulmonary nodules suggestive of metastasis on thoracic imaging was uncertain in 9 dogs, it was certain in the remaining 137 dogs, with nodules present in 16 (11.7%) dogs (5/77 [6%] with grade 1 STSs, 2/36 [6%] with grade 2 STSs, and 9/24 [38%] with grade 3 STSs). The odds of such pulmonary nodules being present on initial examination were higher (OR, 10.8 and 3.14, respectively) for dogs with grade 3 STSs (vs grade 1 or 2 STSs) and for dogs with an STS duration > 3 months (versus ≤ 3 months).

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that pulmonary staging was a low-yield diagnostic procedure for dogs with grade 1 or 2 cutaneous or subcutaneous STSs, especially when tumors had been present for ≤ 3 months.

A Holistic Approach to Bone Tumors in Dogs and Cats: Radiographic and Histologic Correlation

The skeletal system is a common site for neoplasia in dogs and cats, and primary bone tumors may develop from any of the mesenchymal tissues present in bone. Imaging and histopathology are routinely used in the diagnosis of bone tumors, and the 2 techniques are highly complementary. While imaging may be highly suggestive of a specific diagnosis and treatment may be instituted based on this, definitive diagnosis requires histopathology of either incisional or excisional biopsies or an amputation specimen. However, there are a number of diagnostic dilemmas when the pathologist interprets bone biopsy samples, such as distinguishing reactive bone and tumor bone, fracture callus and tumor bone, different benign fibro-osseous lesions, and different types of bone sarcoma. This review outlines the characteristic radiographic and histologic changes associated with these diagnostic problems to aid in resolving them. When a holistic approach is taken to evaluation of the signalment, history, and clinical, radiologic, and microscopic features, a diagnosis may be possible. The pathologist is greatly assisted in the interpretation of bone samples by having access to imaging and should routinely request either the images or the imaging reports if they are not received from submitting veterinarians.

Canine thyroid carcinoma prognosis following the utilisation of computed tomography assisted staging

BACKGROUND

Metastatic disease is frequently present at the time of diagnosis of canine thyroid carcinoma; however, utilisation of computed tomography (CT) alone for staging pre-treatment has been rarely reported in the veterinary literature.

METHODS

The aims of this retrospective study were to stage affected dogs using CT findings of the cervical and thoracic regions, combined with histopathology/cytology results, in order to assess whether metastatic disease/WHO staging was of prognostic significance.

RESULTS

Fifty-eight dogs were included in the study. Classification of cases into WHO stages I, II, III and IV were 10%, 50%, 9% and 31%, respectively. No statistically significant effect of WHO stage classification on overall survival/follow-up time was found (P = .576). Surgery resulted in a statistically significant increase in overall survival/follow-up time (P < .01). There was no statistically significant effect on overall survival/follow-up time in dogs that received medical therapy, either as sole therapy or as an adjunctive post-surgery (P = .198).

CONCLUSION

In summary, this study documents the metastatic rate of canine thyroid carcinoma using CT for staging pre-treatment. Staging utilising CT revealed a higher distant metastatic rate in dogs with thyroid carcinoma when compared to historical studies using different imaging techniques. As long-term outcomes are possible for cases with advanced disease, surgical intervention could still be considered.

Renal adenocarcinoma associated with hypertrophic osteopathy in a cat

Case summary

A 10-year-old neutered male domestic shorthair cat was diagnosed with renal adenocarcinoma associated with hypertrophic osteopathy. The cat was referred for chronic ambulation difficulties. The physical examination showed a painful thickening of all four limbs, a right cranial abdominal mass and a conjunctival hyperaemia. Radiographic findings were consistent with extensive periosteal new bone formation involving not only the diaphyses of the fore- and hindlimbs, but also of the pelvis, tarsus and carpus. Abdominal ultrasonography and CT revealed a mass within the right kidney and a primary neoplasm was suspected. A ureteronephrectomy of the right kidney was performed and histopathology confirmed the diagnosis of renal adenocarcinoma. Although clinical improvement of the lameness occurred after surgery, no radiographic changes of hypertrophic osteopathy lesions were observed at the 9-month follow-up.

Relevance and novel information

Feline cases of hypertrophic osteopathy are rarely reported in the literature and only a few of them were associated with abdominal neoplastic diseases. To our knowledge, this is the first case of renal adenocarcinoma associated with hypertrophic osteopathy in a cat.

A retrospective analysis on the outcome of 18 dogs with malignant ovarian tumours

Little evidence is available regarding the prognosis of dogs with malignant ovarian tumours. The objective of this retrospective study was to describe the outcomes and determine the prognostic factors for dogs with malignant ovarian tumours following treatment, including surgery with or without adjuvant therapy. Eighteen dogs were studied, their median age was 12 years (range: 7-15 years), and their median body weight was 6.9 kg (range: 2.3-17.8 kg). Following histopathologic diagnoses revealed that granulosa cell tumour was the most common type (n = 9), followed by dysgerminoma (n = 5), and adenocarcinoma (n = 4). Eleven dogs had surgery alone. Seven dogs had surgery with adjuvant therapy, including chemotherapy and/or radiotherapy. The median survival time (ST) was 1009 days when only deaths owing to the ovarian tumours were considered, and predictors of median ST were T-category (≥ T3, 443 days vs ≤ T2, 1474 days; P = .002), presence of metastatic disease (present, 391 days vs absent, 1474 days; P < .001) and lymphovascular space invasion (present, 428 days vs absent, 1474 days; P = .003) in a univariate analysis. Median ST in dogs with granulosa cell tumour seemed longer than in dogs with dysgerminoma and adenocarcinoma, although the difference was statistically insignificant (1474 days vs 458 days, respectively; P = .10). Considering the good prognosis, aggressive treatment can be recommended for dogs with malignant ovarian tumours, especially early-stage cases. Despite metastasis being present at diagnosis, half of the dogs with metastasis survived for more than 1 year.

Lung ultrasonography findings in dogs with various underlying causes of cough

OBJECTIVE

To characterize lung ultrasonography (LUS) findings in dogs with a primary clinical complaint of cough.

ANIMALS

100 client-owned coughing dogs.

PROCEDURES

A standardized LUS examination was performed for all dogs to quantify the number of B lines and identify subpleural abnormalities at 4 sites on each hemithorax. The final clinical diagnosis (reference standard) was determined by medical record review, and sensitivity and specificity of LUS for the diagnosis of selected causes of cough was determined.

RESULTS

Common underlying causes of cough included dynamic airway collapse (n = 37), cardiogenic pulmonary edema (CPE; 12), and bronchitis (10). Compared with dogs with other causes of cough, dogs with bacterial pneumonia (n = 7) were more likely to have subpleural shred signs, whereas dogs with pulmonary neoplasia (4) were more likely to have subpleural nodule signs. Dogs with CPE had higher total B-line scores and higher numbers of LUS sites strongly positive for B lines (> 3 B lines/site) than other dogs. The LUS criteria of total B-line score ≥ 10 and presence of ≥ 2 sites strongly positive for B lines were each 92% sensitive and 94% specific for CPE diagnosis. Notably, 18% (16/88) of dogs with noncardiac causes of cough had been treated previously with diuretics because of prior CPE misdiagnosis.

CONCLUSIONS AND CLINICAL RELEVANCE

LUS profiles in dogs with cough differed by the underlying cause. In dogs with a clinical history of cough, this imaging modality could be diagnostically useful, particularly to help exclude the possibility of underlying CPE.

Outcomes of 43 small breed dogs treated for splenic hemangiosarcoma

OBJECTIVE

To determine outcome and prognostic factors in small breed dogs in which hemangiosarcoma was diagnosed and whether outcomes differed between small and large breed dogs with splenic hemangiosarcoma.

STUDY DESIGN

Bi-institutional retrospective study.

ANIMALS

Forty-three small breed (<20 kg) and 94 large breed client-owned dogs.

METHODS

Medical records were reviewed to identify dogs treated with splenectomy for splenic hemangiosarcoma. Data acquired included signalment, preoperative staging, bloodwork results, surgical findings, histopathologic findings, administration of chemotherapy, presence/absence of metastatic disease, and survival time (ST). Cox proportional hazards regression analysis was performed to assess prognostic factors associated with survival.

RESULTS

The overall median ST was 116 days and 97 days for small and large breed dogs, respectively. The ST for dogs treated with surgery and chemotherapy was 207 and 139 days for small and large breed dogs, respectively. The disease-free interval (DFI) was 446 and 80 days for small and large breed dogs, respectively. Dog size was associated with DFI (P = .02) but not with ST (P = .09). The presence of metastasis at diagnosis was associated with decreased ST in small (P = .03) and large (P = .0009) breed dogs. Administration of chemotherapy (P = .02) was associated with increased ST (P = .02) in small breed dogs.

CONCLUSION

The ST was not different in small and large breed dogs with splenic hemangiosarcoma treated with splenectomy and chemotherapy.

CLINICAL SIGNIFICANCE

Prognosis remains poor despite aggressive therapies in small and large breed dogs.

Coughing in Small Animal Patients

Cough is one of the most common complaints in human medicine. In veterinary medicine cough is equally frequent and plays a significant role in an owner's perception of their pet's quality of life. In human and veterinary medicine, therapy for chronic cough is often ineffective. The complexity of the cough pathway and species differences have made it difficult to develop an effective antitussive agent for veterinary patients. The few effective antitussive agents currently available are associated with significant adverse effects. Fortunately, several promising drugs currently being studied in human clinical trials may offer options for use of novel antitussive therapies in small animal patients. This article reviews current understanding about cough pathophysiology, diagnostic strategies used to uncover underlying etiology of cough, and examines available options for controlling cough, including novel antitussive therapies used in human medicine.

Endogenous lipoid pneumonia associated with pulmonary neoplasia in three dogs

Endogenous lipoid pneumonia is a poorly characterised condition in veterinary medicine, particularly in dogs, but it is well recognised in association with lung neoplasia in humans. This case series describes three unique cases of endogenous lipoid pneumonia associated with lung neoplasia, including clinical, imaging, cytological findings and outcome. Clinical presentation and imaging lesions can appear non-specific and may be obscured by neoplastic infiltrate and so diagnosis requires cytology or histopathology. Awareness of endogenous lipoid pneumonia in dogs with pulmonary neoplasia has an impact on staging and monitoring, treatment of clinical signs and quality of life and also aids appropriate use of antimicrobials.

Significant advances in veterinary oncology - 60 years on

The first edition of the Journal of Small Animal Practice published in February 1960, contained a paper entitled "Recent Treatments of Malignant Neoplasia" by Dr Larry Owen. Now we have reached the 60th anniversary of JSAP, that article provides a baseline from which to review subsequent advances in veterinary oncology, which now includes worldwide networks that have resulted in veterinary oncology becoming the multidisciplinary speciality that it is today. There certainly have been many advances in understanding of the pathology and epidemiology of animal cancers and in methods of diagnosis and treatment. However, the subject has become so large and diverse that not all aspects can be covered in detail here. It should also be acknowledged that there are still many gaps in knowledge in this field and that, because of a lack of randomised clinical trials, the evidence base for what is often regarded as "standard of care" is weak.

Development of a zoomorphic test specimen for constancy testing on digital X-ray systems in veterinary radiology

Background

Technical failures and incorrect usage of digital X-ray systems may lead to a decreasing image quality, artefacts and a higher dose exposure of staff and patients. Although there are no regulations regarding constancy testing in veterinary radiology all operators are required to avoid unnecessary exposure. The aim of this study was to develop a reasonably inexpensive zoomorphic 3D-printed test specimen for constancy testing that allows the detection of changing image quality by visual analysis.

Primarily, a calibration curve of the attenuation factor of the 3D-printing material (ZP150) was determined. MATLAB converted every pixel value of a thorax X-ray image of a Beagle dog into an equivalent thickness of printing material. The thickness distribution was printed using a 3D-printer. This printed test specimen was additionally provided with five thin aluminium discs to simulate lung nodules.

To evaluate the usability for constancy testing 12 X-ray images of the test specimen were made. Two images (reference and control) were taken with the minimum dose in order to obtain images suitable for diagnosis purposes. Eight images were taken with a dose differing 30–140% from the reference dose by varying current–time product (mAs) or tube voltage (kVp). Two images were taken with the same parameters as the reference image but edited with different image processing. Six veterinarians (general practitioners) evaluated ten chosen structures in the X-ray images in a Visual Grading Analysis and scored the image quality of these structures for every image in comparison to the reference image. A Visual Grading Analysis Score was calculated and statistically analysed.

Results

A higher current–time product led to a negligibly better evaluation of the X-ray image. The lower the current–time product the worse the X-ray images were scored. Likewise, both increasing and decreasing of the tube voltage led to lower scores.

Conclusions

A zoomorphic test specimen can be used for constancy testing of digital X-ray systems in veterinary medicine. Especially a lower dose can be recognised due to deviation in the image quality when compared to the reference image. The 3D-printed test specimen is less expensive than test equipment used in human medicine.

Survival analysis in dogs with urinary transitional cell carcinoma that underwent whole-body computed tomography at diagnosis

This retrospective study aimed to evaluate factors associated with survival and to compare characteristics between tumour localizations in dogs with urinary transitional cell carcinoma (TCC) that underwent whole-body computed tomography (CT) at diagnosis. Dogs with histologically confirmed TCC that received medical therapy between 2010 and 2017 were included; dogs that underwent surgery or radiotherapy for the primary tumour were excluded. According to the CT findings, primary tumour localization (classified into the Bladder, Urethra and Bladder and Urethra groups), prostate involvement, iliosacral lymphadenomegaly, sternal lymphadenomegaly and metastasis to the bone and lung were evaluated for survival analysis. CT at diagnosis revealed iliosacral lymphadenomegaly, sternal lymphadenomegaly, bone metastasis and lung metastasis in 47.7%, 18.5%, 24.6% and 35.4% of the 65 included dogs, respectively. The overall median survival time was 196 days. On multivariable analysis, TCC localization (hazard ratio [HR], 1.90; P = .037), bone metastasis (HR, 2.76; P = .013) and sternal lymphadenomegaly (HR, 3.56; P = .004) were significantly associated with survival. Compared to the Bladder group (n = 16), the Urethra group (n = 26) had higher metastasis rates to the bone (6.3% vs 42.3%; P = .045) and lung (6.3% vs 46.2%; P = .022). The survival time was shorter in the Urethra group than in the Bladder group (121.5 vs 420 days; P < .001), and it was similar only in female dogs (247 vs 420 days; P = .031). These findings suggest that whole-body CT could be valuable for predicting the prognosis in urinary TCC.

Histiocytic Sarcoma and Hemangiosarcoma Update

Histiocytic sarcoma (HS) and hemangiosarcoma (HSA) are uncommon and aggressive neoplasms that develop much more frequently in dogs than in cats. Breed-specific predispositions have been identified for both cancers. The development of novel diagnostics is underway and may aid in earlier diagnosis. Therapeutic approaches to HS and HSA depend on the stage of disease and may include surgery, radiation therapy, and chemotherapy. Such interventions improve outcome; however, aside from a small number of clinical circumstances, both diseases are considered largely incurable. Continued efforts toward the identification of driver mutations and subsequent druggable targets may lead to improvements in long-term prognosis.

Imaging in Non-neurologic Oncologic Treatment Planning of the Head and Neck

Imaging is critical for the diagnosis and staging of veterinary oncology patients. Although cytology or biopsy is generally required for diagnosis, imaging characteristics inform the likelihood of a cancer diagnosis, can result in a prioritized list of differentials that guide further staging tests, and assist in the planning of surgery, radiation, and chemotherapy options. Advanced imaging, such as CT and MRI, can better define the extent of disease for surgical and radiation planning for head and neck cancer cases in particular. Additionally, new imaging technologies are continually being translated into veterinary fields, and they may provide more options for cancer patients as they become more widely available.

Prevalence, distribution, and clinical characteristics of hemangiosarcoma-associated skeletal muscle metastases in 61 dogs: A whole body computed tomographic study

BACKGROUND

Skeletal muscle metastases (SMMs) have been described sporadically in canine oncology.

HYPOTHESIS/OBJECTIVES

To determine the prevalence, localization, and clinical signs of SMMs associated with hemangiosarcoma (HSA) in a population of dogs presented for whole body computed tomography (CT).

ANIMALS

Dogs with a histologically confirmed HSA and a tissue core specimen or fine needle aspirate of suspected metastatic lesions were included in the study.

METHODS

Retrospective study. Dogs with a final diagnosis of visceral or muscular HSA that underwent whole body CT scan were enrolled in the study. Final diagnosis of primary tumor and SMMs was reached by histology, cytology, or both. Signalment, clinical signs, localization of the primary lesion, and metastases characteristics were reviewed.

RESULTS

Sixty-one dogs met the inclusion criteria. Skeletal muscle metastases were detected in 15 dogs (24.6%) and all of these dogs had also metastases in ≥1 sites. Presence of SMMs was significantly higher in males but was not significantly related to age, neuter status, breed, localization, and dimensions of the primary tumor. Nine of 15 (60.0%) dogs with SMMs showed lameness or reluctance to move whereas these signs were not recorded in any of the 42 dogs without SMMs (P < .001).

CONCLUSION AND CLINICAL IMPORTANCE

Prevalence of SMMs in our population of dogs with HSA was higher in comparison to previous studies in the human and veterinary medical literature. Whole body CT is recommended for staging of dogs with HSA, because SMMs could be missed by clinical examination and traditional diagnostic imaging modalities.

Outcome following cosmetic rostral nasal reconstruction after planectomy in 26 dogs

OBJECTIVE

To report the outcome and owner satisfaction after planectomy for nasal planum neoplasia with cosmetic reconstruction with bilateral labial mucocutaneous rotation flaps in dogs.

STUDY DESIGN

Multi-institutional, retrospective case series.

ANIMALS

Twenty-six client-owned dogs.

METHODS

Medical records were searched for dogs that had undergone the procedure. Signalment, diagnosis, surgery, complications, requirement for revision surgery, recurrence, and survival information were recorded. Owners were contacted by telephone about their dog's quality of life after the procedure and their satisfaction with their dog's outcome.

RESULTS

Twenty-five dogs underwent radical planectomy, and 1 dog underwent resection of the nasal planum. Twenty-four dogs had a diagnosis of squamous cell carcinoma, 1 had a diagnosis of atypical adenocarcinoma, and 1 had a diagnosis of a mast cell tumor. Complications occurred in 19 (73%) dogs, with 9 dogs requiring revision surgery; 1 dog not surviving to discharge. Median survival time was 1542 days (range, 3-2010). Recurrence of the primary tumor was suspected in 2 (7.7%) dogs, both with narrow or incomplete excision. Among 11 owners interviewed, 10 were satisfied with their dog's appearance, and 8 reported they would consent to the procedure again.

CONCLUSION

Dehiscence was common after this procedure, but local tumor control and survival times were excellent. Owner satisfaction was high, although preoperative client education is vital.

CLINICAL SIGNIFICANCE

This technique should be considered as a viable option for dogs with nasal planum neoplasia given the high rate of recurrence with less aggressive treatment. Complications common following surgery, but do not persist long term and survival times were excellent.

Intraluminal tracheal lipoma as a rare cause of dyspnoea in a dog

Background

Tracheal tumors are rarely diagnosed in veterinary medicine and the majority of tracheal neoplasia reported in adult dogs are malignant. Intratracheal lipoma has not been previously reported in the veterinary literature.

Case presentation

A 7-year-old Briard dog was evaluated for inspiratory dyspnoea and an inspiratory wheeze. Cervical radiographs and tracheoscopic examination revealed an intratracheal mass that was surgically removed. The dog has been asymptomatic after the surgery.

Conclusions

Based on histopathology, the mass was diagnosed as lipoma. To the authors‘ knowledge, this is the first published report of an intratracheal lipoma in the veterinary literature.

Distribution of alveolar-interstitial syndrome in dogs and cats with respiratory distress as assessed by lung ultrasound versus thoracic radiographs

OBJECTIVE

To assess distribution of alveolar-interstitial syndrome (AIS) detected by lung ultrasound (LUS) compared to thoracic radiographs (TXR).

DESIGN

Prospective study.

SETTING

University teaching hospital.

ANIMALS

Seventy-six dogs and 24 cats with acute respiratory distress or tachypnea.

INTERVENTIONS

Patients underwent LUS and TXR within 6 hours. Lung ultrasound images were scored for presence and quantity of B-lines in 4 lung quadrants (right cranial, right caudal, left cranial, left caudal). An individual LUS quadrant was scored positive if > 3 B-lines were observed within a single intercostal space. Dorsoventral TXR were scored for presence of AIS in the same 4 quadrants. An individual TXR quadrant was scored positive if infiltrate was present in ≥ 25% of the quadrant. Medical records were evaluated for final diagnosis.

MEASUREMENTS AND MAIN RESULTS

Quadrant-by-quadrant spatial agreement in assigning AIS using LUS versus TXR was fair (K = 0.24 - 0.56). Lung ultrasound scored a higher number of quadrants positive per patient (2.65 ± 1.59 vs. 2.13 ± 1.48; P = 0.012). Patterns of distribution of AIS differed significantly based on final diagnosis. Patients with left-sided congestive heart failure were more likely to have diffuse AIS on LUS (P < 0.001) or bilateral caudal AIS on TXR (P = 0.04) while patients with noncardiac disease were more likely to have absence of AIS in all quadrants using either modality (P < 0.001). Differences in spatial distribution of AIS were also noted among disease subcategories.

CONCLUSIONS

Lung ultrasound and TXR were both useful to detect and categorize distribution of alveolar or interstitial pulmonary pathology. Spatial agreement between modalities was only fair. Overall, LUS detected a higher incidence of AIS compared to TXR. Both modalities detected differences in distribution of AIS based on final diagnosis, suggesting that a regional pattern-based approach to thoracic imaging may prove diagnostically useful.

Prognosis for dogs with stage III osteosarcoma following treatment with amputation and chemotherapy with and without metastasectomy

OBJECTIVE To determine survival times of selected dogs with metastatic (stage III) osteosarcoma, whether disease-free interval (DFI) was associated with survival time after diagnosis of stage III disease (ie, stage III survival time), and whether a survival benefit of metastasectomy existed. DESIGN Retrospective case series with nested cohort study. ANIMALS 194 client-owned dogs treated for histologically confirmed appendicular osteosarcoma from 1997 through 2009. PROCEDURES Dogs were included if they had stage I or II osteosarcoma at the time of initial evaluation, had amputation of the affected appendage and ≥ 1 dose of chemotherapy afterward, and developed metastasis within the follow-up period or prior to death. Data collected from the medical records included signalment, primary tumor location, clinical and laboratory findings, whether metastasectomy was performed, and outcome. Various factors were examined for associations with outcome. RESULTS Dogs that received no treatment for the metastasis had a median survival time between 49 and 57 days after diagnosis of stage III osteosarcoma. Duration of the preceding DFI had no association with this period. Metastasectomy alone was associated with a longer median stage III survival time (232 days) than no metastasectomy (49 days). Among all dogs identified as qualifying for pulmonary metastasectomy on the basis of < 3 pulmonary nodules visible on thoracic radiographs and a DFI > 275 days (n = 21), a survival advantage was also identified for those that actually received pulmonary metastasectomy (6). CONCLUSIONS AND CLINICAL RELEVANCE Preceding DFI had no influence on survival time of dogs with stage III osteosarcoma. Metastasectomy was associated with an increase in survival time for selected dogs.

Canine cancer immunotherapy studies: linking mouse and human

Despite recent major clinical breakthroughs in human cancer immunotherapy including the use of checkpoint inhibitors and engineered T cells, important challenges remain, including determining the sub-populations of patients who will respond and who will experience at times significant toxicities. Although advances in cancer immunotherapy depend on preclinical testing, the majority of in-vivo testing currently relies on genetically identical inbred mouse models which, while offering critical insights regarding efficacy and mechanism of action, also vastly underrepresent the heterogeneity and complex interplay of human immune cells and cancers. Additionally, laboratory mice uncommonly develop spontaneous tumors, are housed under specific-pathogen free conditions which markedly impacts immune development, and incompletely model key aspects of the tumor/immune microenvironment. The canine model represents a powerful tool in cancer immunotherapy research as an important link between murine models and human clinical studies. Dogs represent an attractive outbred combination of companion animals that experience spontaneous cancer development in the setting of an intact immune system. This allows for study of complex immune interactions during the course of treatment while also directly addressing long-term efficacy and toxicity of cancer immunotherapies. However, immune dissection requires access to robust and validated immune assays and reagents as well as appropriate numbers for statistical evaluation. Canine studies will need further optimization of these important mechanistic tools for this model to fulfill its promise as a model for immunotherapy. This review aims to discuss the canine model in the context of existing preclinical cancer immunotherapy models to evaluate both its advantages and limitations, as well as highlighting its growth as a powerful tool in the burgeoning field of both human and veterinary immunotherapy.

Retrospective Evaluation of Whole Body Computed Tomography for Tumor Staging in Dogs with Primary Appendicular Osteosarcoma

OBJECTIVE

To evaluate whole body computed tomography (CT) for staging canine appendicular osteosarcoma.

STUDY DESIGN

Retrospective case series.

ANIMALS

Client-owned dogs diagnosed with appendicular osteosarcoma (n=39).

METHODS

Medical records for client-owned dogs diagnosed with appendicular osteosarcoma from August 2008 to July 2014 were reviewed. Dogs were included if they had a confirmed diagnosis of appendicular osteosarcoma and were staged using whole body CT. Data collected included signalment, body weight, primary tumor location, serum alkaline phosphatase (ALP) activity, findings on 3-view thoracic radiographs, cytologic or histologic results, and findings on CT.

RESULTS

Thirty-nine dogs (median age 8.5 years; median body weight 37 kg) had osteosarcoma of the distal radius (n=17), proximal humerus (11) and other sites. Serum ALP activity was elevated in 14 dogs. Bone metastasis was not detected in any dog on whole body CT. Pulmonary metastasis was considered definitive on CT based on board certified radiologist assessment in 2/39 dogs (5%). Two additional dogs (2/39, 5%) had soft tissue masses diagnosed on CT, consistent with concurrent, non-metastatic malignancies.

CONCLUSION

Bone metastases were not identified in any dog with whole body CT. Thoracic and abdominal CT detected lung lesions and concurrent neoplasia in dogs with primary appendicular osteosarcoma. Whole body CT may be a useful adjunct to other screening tests for disseminated malignancy.

Use of manual alveolar recruitment maneuvers to eliminate atelectasis artifacts identified during thoracic computed tomography of healthy neonatal foals

OBJECTIVE To evaluate use of single manual alveolar recruitment maneuvers (ARMs) to eliminate atelectasis during CT of anesthetized foals. ANIMALS 6 neonatal Standardbred foals. PROCEDURES Thoracic CT was performed on spontaneously breathing anesthetized foals positioned in sternal (n = 3) or dorsal (3) recumbency when foals were 24 to 36 hours old (time 1), 4 days old (time 2), 7 days old (time 3), and 10 days old (time 4). The CT images were collected without ARMs (all times) and during ARMs with an internal airway pressure of 10, 20, and 30 cm H₂O (times 2 and 3). Quantitative analysis of CT images measured whole lung and regional changes in attenuation or volume with ARMs. RESULTS Increased attenuation and an alveolar pattern were most prominent in the dependent portion of the lungs. Subjectively, ARMs did not eliminate atelectasis; however, they did incrementally reduce attenuation, particularly in the nondependent portion of the lungs. Quantitative differences in lung attenuation attributable to position of foal were not identified. Lung attenuation decreased significantly (times 2 and 3) and lung volume increased significantly (times 2 and 3) after ARMs. Changes in attenuation and volume were most pronounced in the nondependent portion of the lungs and at ARMs of 20 and 30 cm H₂O. CONCLUSIONS AND CLINICAL RELEVANCE Manual ARMs did not eliminate atelectasis but reduced attenuation in nondependent portions of the lungs. Positioning of foals in dorsal recumbency for CT may be appropriate when pathological changes in the ventral portion of the lungs are suspected.