The Experts below are selected from a list of 3954 Experts worldwide ranked by ideXlab platform
Michele A. Keyerleber - One of the best experts on this subject based on the ideXlab platform.
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utility of computed tomography versus abdominal ultrasound examination to identify iliosacral lymphadenomegaly in dogs with Apocrine Gland adenocarcinoma of the anal sac
Journal of Veterinary Internal Medicine, 2016Co-Authors: S Palladino, Michele A. Keyerleber, Ryan King, K E BurgessAbstract:Background Apocrine Gland adenocarcinoma of the anal sac (AGAAS) is associated with high rates of iliosacral lymph node metastasis, which may influence treatment and prognosis. Magnetic resonance imaging (MRI) recently has been shown to be more sensitive than abdominal ultrasound examination (AUS) in affected patients. Objective To compare the rate of detection of iliosacral lymphadenomegaly between AUS and computed tomography (CT) in dogs with AGAAS. Animals Cohort A: A total of 30 presumed normal dogs. Cohort B: A total of 20 dogs with AGAAS that underwent AUS and CT. Methods Using cohort A, mean normalized lymph node : aorta (LN : AO) ratios were established for medial iliac, internal iliac, and sacral lymph nodes. The CT images in cohort B then were reviewed retrospectively and considered enlarged if their LN : AO ratio measured 2 standard deviations above the mean normalized ratio for that particular node in cohort A. Classification and visibility of lymph nodes identified on AUS were compared to corresponding measurements obtained on CT. Results Computed tomography identified lymphadenomegaly in 13 of 20 AGAAS dogs. Of these 13 dogs, AUS correctly identified and detected all enlarged nodes in only 30.8%, and either misidentified or failed to detect additional enlarged nodes in the remaining dogs. Despite limitations in identifying enlargement in all affected lymph nodes, AUS identified at least 1 enlarged node in 100% of affected dogs. Conclusion and Clinical Importance Abdominal ultrasound examination is an effective screening test for lymphadenomegaly in dogs with AGAAS, but CT should be considered in any patient in which an additional metastatic site would impact therapeutic planning.
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Three-dimensional conformal versus non-graphic radiation treatment planning for Apocrine Gland adenocarcinoma of the anal sac in 18 dogs (2002-2007).
Veterinary and comparative oncology, 2011Co-Authors: Michele A. Keyerleber, Tracy L. Gieger, Hollis N. Erb, M. S. Thompson, Margaret C. McenteeAbstract:Differences in dose homogeneity and irradiated volumes of target and surrounding normal tissues between 3D conformal radiation treatment planning and simulated non-graphic manual treatment planning were evaluated in 18 dogs with Apocrine Gland adenocarcinoma of the anal sac. Overall, 3D conformal treatment planning resulted in more homogenous dose distribution to target tissues with lower hot spots and dose ranges. Dose homogeneity and guarantee of not under-dosing target tissues with 3D conformal planning came at the cost, however, of delivering greater mean doses of radiation and of irradiating greater volumes of surrounding normal tissue structures.
Timothy J. Stein - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of adjuvant carboplatin chemotherapy in the management of surgically excised anal sac Apocrine Gland adenocarcinoma in dogs
Veterinary and comparative oncology, 2013Co-Authors: Raelene M. Wouda, Juan Borrego, Nicholas S. Keuler, Timothy J. SteinAbstract:There is no widely accepted standard of care for canine anal sac Apocrine Gland adenocarcinoma (ASAGAC). Surgery alone is inadequate in many cases, but the benefit of adjuvant chemotherapy is not well established. The primary objective of this retrospective study was to evaluate the role of carboplatin chemotherapy in the post-operative management of ASAGAC. Seventy-four dogs with naturally occurring ASAGAC underwent surgery. Forty-four dogs received adjuvant carboplatin and 30 did not. Median overall survival (OS) was 703 days. Median time to progression (TTP) was 384 days. Only primary tumour size and lymph node metastasis at diagnosis significantly impacted the outcome. Differences in OS and TTP, between the dogs that received adjuvant carboplatin and those that did not, failed to reach statistical significance. Treatment of progressive disease, whilst not limited to chemotherapy, significantly prolonged the survival. This study shows that adjuvant carboplatin chemotherapy is well tolerated and may have a role in the management of dogs with ASAGAC.
Amy K. Leblanc - One of the best experts on this subject based on the ideXlab platform.
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Expression of PDGFR-β and Kit in canine anal sac Apocrine Gland adenocarcinoma using tissue immunohistochemistry
Veterinary and comparative oncology, 2011Co-Authors: R. J. Brown, Shelley J. Newman, D. C. Durtschi, Amy K. LeblancAbstract:Canine anal sac Apocrine Gland adenocarcinoma (ASAGAC) is an uncommon but highly invasive and metastatic malignancy. Toceranib phosphate (Palladia) is a receptor tyrosine kinase (RTK) inhibitor that targets several members of the split kinase RTK family. These membrane receptors are important for cell cycling, apoptosis and angiogenesis, all of which can contribute to carcinogenesis. The objective of this study was to evaluate archived, paraffin-embedded canine ASAGAC and normal canine anal sacs for immunohistochemical detection of Kit and platelet-derived growth factor receptor beta (PDGFR-β). Two of 77 neoplasms (2.6%) expressed Kit. Fifteen of the neoplasms (19.5%) were positive for PDGFR-β expression. None of the normal canine anal sac epithelium expressed Kit or PDGFR-β. Because of these results, further investigation should be considered to determine the role of RTKs in the clinical course and treatment of canine ASAGAC.
Janean Fidel - One of the best experts on this subject based on the ideXlab platform.
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Comparison of abdominal ultrasound and magnetic resonance imaging for detection of abdominal lymphadenopathy in dogs with metastatic Apocrine Gland adenocarcinoma of the anal sac
Veterinary and comparative oncology, 2013Co-Authors: C. L. Anderson, C. S. Mackay, G. D. Roberts, Janean FidelAbstract:Imaging studies in humans with anal and rectal cancer indicate that magnetic resonance imaging (MRI) is a more sensitive technique than abdominal ultrasound (AUS) for the detection of abdominal lymphadenopathy. The purpose of this retrospective study was to directly compare the efficacy of these two techniques in detecting abdominal lymphadenopathy in dogs with Apocrine Gland adenocarcinoma of the anal sac (AGAAS). Six dogs with histologically confirmed AGAAS and histopathologic confirmation of metastasis to abdominal lymph nodes (LNs) had AUS and abdominal MRI. AUS identified lymphadenopathy in two of six dogs, whereas MRI identified lymphadenopathy in all the six dogs. Lymphadenopathy was predominantly sacral in location, with involvement of the medial iliac and hypogastric LNs in only two cases. These data suggest that MRI is more sensitive than AUS for detecting sacral abdominal lymphadenopathy in dogs with AGAAS. As such, MRI could be considered in any patient with AGAAS for initial staging of this disease.
K E Burgess - One of the best experts on this subject based on the ideXlab platform.
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utility of computed tomography versus abdominal ultrasound examination to identify iliosacral lymphadenomegaly in dogs with Apocrine Gland adenocarcinoma of the anal sac
Journal of Veterinary Internal Medicine, 2016Co-Authors: S Palladino, Michele A. Keyerleber, Ryan King, K E BurgessAbstract:Background Apocrine Gland adenocarcinoma of the anal sac (AGAAS) is associated with high rates of iliosacral lymph node metastasis, which may influence treatment and prognosis. Magnetic resonance imaging (MRI) recently has been shown to be more sensitive than abdominal ultrasound examination (AUS) in affected patients. Objective To compare the rate of detection of iliosacral lymphadenomegaly between AUS and computed tomography (CT) in dogs with AGAAS. Animals Cohort A: A total of 30 presumed normal dogs. Cohort B: A total of 20 dogs with AGAAS that underwent AUS and CT. Methods Using cohort A, mean normalized lymph node : aorta (LN : AO) ratios were established for medial iliac, internal iliac, and sacral lymph nodes. The CT images in cohort B then were reviewed retrospectively and considered enlarged if their LN : AO ratio measured 2 standard deviations above the mean normalized ratio for that particular node in cohort A. Classification and visibility of lymph nodes identified on AUS were compared to corresponding measurements obtained on CT. Results Computed tomography identified lymphadenomegaly in 13 of 20 AGAAS dogs. Of these 13 dogs, AUS correctly identified and detected all enlarged nodes in only 30.8%, and either misidentified or failed to detect additional enlarged nodes in the remaining dogs. Despite limitations in identifying enlargement in all affected lymph nodes, AUS identified at least 1 enlarged node in 100% of affected dogs. Conclusion and Clinical Importance Abdominal ultrasound examination is an effective screening test for lymphadenomegaly in dogs with AGAAS, but CT should be considered in any patient in which an additional metastatic site would impact therapeutic planning.
