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Brain: Hamartoma in the callosal sulcus. This rare lesion consists of choroid plexus components that are epithelia, fatty tissues, abundant collagen fibers and small vessels. It is considered that the lesion is possibly an ectopic tissue.
Source publication
The purpose of our publication is to widely communicate the pictures of spontaneous findings occurring in beagles. Spontaneous arteritis occurs commonly in beagles. Frequent sites of arteritis are the heart, spleen, pancreas, epididymis and spinal cord. Morphological similarities between spontaneous and drug-induced arterial lesions may cause confu...
Citations
... Distal and collecting tubules are also included if the toxicants or toxic metabolites remain in the urine. [47] Fortunately, the injured renal tubules in this study showed reversal from the damage characterized by basophilic cytoplasm and karyomegaly of regenerated epithelial cells, and thickened basement membranes, which showed the same characteristics described by Sato et al. [54] from chemicalinduced chronic injury. This evidence also appeared mostly in the recovery group of female rats. ...
... Similar LUFs have been described as a background finding in beagle dogs. 133 Hormonal manipulation can induce LUFs in rats and monkeys. 134 ...
The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions) Project ( www.toxpath.org/inhand.asp ) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in most tissues and organs from the minipig used in nonclinical safety studies. Some of the lesions are illustrated by color photomicrographs. The standardized nomenclature presented in this document is also available electronically on the internet ( http://www.goreni.org/ ). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous lesions as well as lesions induced by exposure to test materials. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature for lesions in laboratory animals will provide a common language among regulatory and scientific research organizations in different countries and increase and enrich international exchanges of information among toxicologists and pathologists.
... For detailed general considerations on the integument, please refer to the INHAND publication on rodent integument, 85 and, for a detailed description of the anatomy and physiology of canine skin, refer to Muller and Kirk's Small Animal Dermatology. 86 Surveys of skin lesions in beagle dogs are included in the publications of Sato et al 49 and Scudamore. 60 Parasitic diseases in the dog include flea infestations (Ctenocephalides canis and others), sarcoptic mange (Sarcoptes scabiei), and demodectic mange (Demodex canis). ...
... 144,145 Immature prostatic acini have narrow, undeveloped lumina lined by basophilic epithelium that is cuboidal to flattened with a high nuclear to cytoplasmic ratio. 49,143 The amount of connective tissue is relatively higher in the immature prostate than the mature prostate. 143 Maturing prostate can have a patchy distribution of immature small acini with wide interstitium and mature glands with scant stroma. ...
... The lobular distribution is considered evidence that the affected tubular profiles belong to a single, convoluted, seminiferous tubule. 144 Descriptive terminology such as "Sertoli cell-only tubules" have been used or suggested by some authors, 49,151 and the finding can be confused with focal tubular atrophy. However, the high prevalence of this finding in dogs less than 1 year of age suggests "tubule hypoplasia" is an appropriate term. ...
The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions) Project ( www.toxpath.org/inhand.asp ) is a joint initiative of the societies of toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying lesions observed in most tissues and organs from the dog used in nonclinical safety studies. Some of the lesions are illustrated by color photomicrographs. The standardized nomenclature presented in this document is also available electronically on the internet ( http://www.goreni.org/ ). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous lesions, lesions induced by exposure to test materials, and relevant infectious and parasitic lesions. A widely accepted and utilized international harmonization of nomenclature for lesions in laboratory animals will provide a common language among regulatory and scientific research organizations in different countries and increase and enrich international exchanges of information among toxicologists and pathologists.
... The findings in testis (mature), pituitary gland, parathyroid gland, and thymus are consistent with common background lesions described in dogs. 10,11 However, the other common findings (kidney mineralization, thymus atrophy, testis hypoplasia/hypo spermatogenesis, lung infiltrate, and epididymis cell debris) are sometimes attributed to compound administration. Severity, dose dependency, and occurrence of the finding in control animals are all important considerations when determining the significance of a microscopic observation. ...
Implementation of the Clinical Data Interchange Standards Consortium (CDISC)’s Standard for Exchange of Nonclinical Data (SEND) by the United States Food and Drug Administration Center for Drug Evaluation and Research (US FDA CDER) has created large quantities of SEND data sets and a tremendous opportunity to apply large-scale data analytic approaches. To fully realize this opportunity, differences in SEND implementation that impair the ability to conduct cross-study analysis must be addressed. In this manuscript, a prototypical question regarding historical control data (see Table of Contents graphic) was used to identify areas for SEND harmonization and to develop algorithmic strategies for nonclinical cross-study analysis within a variety of databases. FDA CDER’s repository of >1800 sponsor-submitted studies in SEND format was queried using the statistical programming language R to gain insight into how the CDISC SEND Implementation Guides are being applied across the industry. For each component needed to answer the question (defined as “query block”), the frequency of data population was determined and ranged from 6 to 99%. For fields populated <90% and/or that did not have Controlled Terminology, data extraction methods such as data transformation and script development were evaluated. Data extraction was successful for fields such as phase of study, negative controls, and histopathology using scripts. Calculations to assess accuracy of data extraction indicated a high confidence in most query block searches. Some fields such as vehicle name, animal supplier name, and test facility name are not amenable to accurate data extraction through script development alone and require additional harmonization to confidently extract data. Harmonization proposals are discussed in this manuscript. Implementation of these proposals will allow stakeholders to capitalize on the opportunity presented by SEND data sets to increase the efficiency and productivity of nonclinical drug development, allowing the most promising drug candidates to proceed through development.
... Incidental retinal rosettes have been described previously in rabbits, rodents, and dogs, but not in pigs. 51,66,74 Furthermore, the retina of both pig breeds at various ages presented displaced photoreceptors nuclei within the photoreceptor layer, which has also been reported as an incidental finding in normal rodents, nonhuman primate and human. 66,73 A peculiar background change was observed in 2 Göttingen minipigs (3 months and 6 months old), and not in F2 domestic pigs: the optic nerve, near the optic disc, contained a poorly defined and nonencapsulated nodule, which appeared to be composed of dysplastic and ectopic/displaced retinal neurons, as highlighted with immunohistochemistry markers. ...
Pigs are considered one of the relevant animal models for ocular research as they share several histological and anatomical similarities with the human eye. With the increasing interest in juvenile animal models, this study aimed to describe the postnatal development of ocular structures in 16 Göttingen minipigs and 25 F2 domestic pigs, between birth and 6 months of age, using histopathology and immunohistochemistry against Ki-67, caspase-3, calbindin, glial fibrillary acidic protein, rhodopsin, and synaptophysin. All ocular structures in both pig breeds were incompletely developed at birth and for variable periods postnatally. Noteworthy histological features of immaturity included vascularization in the corneal stroma in neonatal Göttingen minipigs, increased cellularity in different substructures, remnants of the hyaloid vasculature, short and poorly ramified ciliary body processes, and a poorly developed cone inner segment. Increased cellular proliferation, highlighted by abundant Ki-67 immunolabeling, was observed in almost all developing structures of the pig eye for variable periods postnatally. Apoptosis, highlighted with caspase-3 immunolabeling, was observed in the retinal inner nuclear layer at birth and in the regressing hyaloid vasculature remnants. Immunohistochemistry against rhodopsin, synaptophysin, and calbindin demonstrated the short size of the developing photoreceptors and the immature cone inner segment morphology. Calbindin labeling revealed significant differences in the amount of positively labeled cone nuclei between the retinal area centralis and the non-area centralis regions. The elongation of Müller cell processes in the developing retina was shown with glial fibrillary acidic protein. In both pig breeds, the eyes reached histomorphological and immunohistochemical maturity at 6 months of age.
... Similar lesions have been recognized as an incidental finding in dogs, and in mice with sternal dislocations. 1,2,5,6,9 Initial reports in dogs were as an incidental microscopic finding in experimental Beagles; however, more recently, grossly discernible epicardial proliferations have been identified in dogs with cardiac abnormalities. 2,5,6,9 These lesions are thought to occur in response to friction between the epicardial surface of the heart and the overlying pericardium. ...
... 1,2,5,6,9 Initial reports in dogs were as an incidental microscopic finding in experimental Beagles; however, more recently, grossly discernible epicardial proliferations have been identified in dogs with cardiac abnormalities. 2,5,6,9 These lesions are thought to occur in response to friction between the epicardial surface of the heart and the overlying pericardium. 1,5,8 A morphologically similar epicardial proliferation has been reported in cattle in association with cardiac lymphoma. ...
Cardiac mesothelial hyperplasia forming pale plaque lesions on the epicardial surface is a common incidental finding in the hearts of aged humans. A similar phenomenon with a more papillary appearance has also been reported as an incidental finding in dogs and mice. These lesions are believed to occur in response to friction between the epicardium and overlying pericardium. We investigated this lesion in adult cattle, a phenomenon that has been associated with bovine leukemia virus infection and epicardial lymphoma. We examined 73 hearts from adult cattle, predominantly of dairy breeds: 53 from a rendering facility and 20 from a state diagnostic laboratory. Cardiac mesothelial hyperplasia was much more prevalent in cattle than in other reported species (97% of examined hearts). The most common distribution was overlying the great vessels in a dark red papillary pattern. Cardiac mesothelial hyperplasia was also variably observed on all 4 cardiac chambers and the pericardium. Occasionally these lesions took on a smooth plaque-like appearance resembling those observed in humans. The lesions varied from 0.25 cm2 to covering 90% of the epicardial surface. No association was observed between cardiac mesothelial hyperplasia and bovine leukemia virus infection or cardiac lymphoma. Cardiac mesothelial hyperplasia was a common incidental finding in bovine hearts that must be distinguished from neoplasia and acute or chronic inflammation.
... Sato et al also list POFs among the spontaneous findings seen in beagles. 50 Age-related differences in POFs are also known for pigs. 51 Polyovular follicles occur with a low frequency in mice and rats, though there may be some slight differences among the various strains. ...
The 2019 annual National Toxicology Program Satellite Symposium, entitled “Pathology Potpourri,” was held in Raleigh, North Carolina, at the Society of Toxicologic Pathology’s 38th annual meeting. The goal of this symposium was to present and discuss challenging diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers’ talks along with select images that were used by the audience for voting and discussion. Various lesions and topics covered during the symposium included aging mouse lesions from various strains, as well as the following lesions from various rat strains: rete testis sperm granuloma/fibrosis, ovarian cystadenocarcinoma, retro-orbital schwannoma, periductal cholangiofibrosis of the liver and pancreas, pars distalis hypertrophy, chronic progressive nephropathy, and renal tubule regeneration. Other cases included polyovular follicles in young beagle dogs and a fungal blood smear contaminant. One series of cases challenged the audience to consider how immunohistochemistry may improve the diagnosis of some tumors. Interesting retinal lesions from a rhesus macaque emphasized the difficulty in determining the etiology of any particular retinal lesion due to the retina’s similar response to vascular injury. Finally, a series of lesions from the International Harmonization of Nomenclature and Diagnostic Criteria Non-Rodent Fish Working Group were presented.
... Several "lookalikes" of this lesion have been identified in people including foam cells seen with lipid storage, ischemic damage, potassium depletion, ethylene glycol intoxication, diabetic hyperglycemia, and renal clear-cell carcinoma.1 Furthermore, unlike what has been demonstrated in people, cytoplasmic vacuolization can be observed in the tubules of the medullary rays (predominately in the straight portion of the proximal tubule) in healthy dogs, which could confound assessment for ON.37,44 Consequently, the RTV appreciated in this study could represent one of the above changes and not be ON. Special stains (such as periodic acid-Shiff staining of granules in the collecting ducts suggestive , the term ON specifically refers to vacuolization and swelling of the straight part of the proximal tubule while the distal tubules and collecting ducts typically remain unchanged.1 ...
Objective
To describe the frequency of renal tubular vacuolization (RTV) as a surrogate of osmotic nephrosis and assess hyperosmolar agents as predictors of RTV severity.
Design
Retrospective study (February 2004–October 2014).
Setting
Veterinary teaching hospital.
Animals
Fifty‐three client‐owned, critically ill dogs that had a postmortem examination.
Interventions
None.
Measurements and Main Results
The frequency, severity, and location of RTV were determined in small group of critically ill dogs postmortem. Logistic regression was performed to assess cumulative 6% HES (670/0.75) and mannitol dose as predictors for RTV severity with presenting serum creatinine concentration, cumulative furosemide dose, and duration of hospitalization as covariates. RTV was noted in 45 (85%) of 53 critically ill dogs and was most commonly located to the medullary rays (68%). Cumulative 6% HES (670/0.75) dose (P = 0.009) and presenting serum creatinine concentration (P = 0.027) were significant predictors of RTV severity. For every 1 mL/kg increase in 6% HES (670/0.75) dose that a dog received, there was 1.6% increased chance of having more severe RTV (OR 1.016; 95% CI 1.004–1.029). In addition, for every 88.4 μmol/L (1 mg/dL) increase in presenting serum creatinine, there was a 22.7% increased chance of having more severe RTV (OR 1.227; 95% CI 1.023–1.472). Cumulative mannitol (P = 0.548) and furosemide (P = 0.136) doses were not significant predictors of RTV severity.
Conclusion
In a small group of critically ill dogs, there was a high frequency of RTV identified on postmortem examination. Administration of 6% HES (670/0.75) and presenting serum creatinine concentration were significant predictors of RTV severity. Larger prospective studies are needed to determine the etiology and significance of RTV in dogs.
... Cystic mucinous hyperplasia is observed in dogs, especially small breeds, including the beagle dog and is characterized by increased numbers of hypertrophic cells with pale cytoplasm and abundant PAS-positive mucus production with areas of chronic inflammatory response and intraluminal debris. This lesion has to be distinguished from hyperplasia of the mucosal epithelium, which is a rare finding with neither copious mucin production nor cystic change (Sato et al. 2012). A case of cystic mucinous hyperplasia of similar appearance has also been described in a ferret, which is a mustelid species like the otter (Reindel and Evans 1987). ...
The 2018 annual National Toxicology Program Satellite Symposium, entitled “Pathology Potpourri,” was held in Indianapolis, Indiana, at the Society of Toxicologic Pathology’s 37th annual meeting. The goal of this symposium was to present and discuss challenging diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers’ talks along with select images that were used by the audience for voting and discussion. Various lesions and other topics covered during the symposium included seminiferous tubule dysgenesis in rats, ameloblast and odontoblast degeneration/necrosis in a Sprague Dawley rat, intestinal leiomyositis in a beagle dog, gallbladder mucinous hyperplasia, focus of hepatocellular alteration and bile duct alteration in otters, renal tubule cytoplasmic vacuolation with basophilic granules in mice treated swith antisense oligonucleotide therapy, a uterine choriocarcinoma in a rhesus macaque, and rete ovarii proliferative ovarian lesions in various aged rat strains. One particularly provocative lesion was a malignant neoplastic proliferation in the renal pelvic region of a cynomolgus macaque from a 21-day study. Additional challenging lesions included thyroid proliferative lesions in zebra fish and gross findings in fish larvae during routine chemical screening. The Rabbit and Minipig International Harmonization of Nomenclature and Diagnostic Criteria Organ Working Groups also presented a series of challenging lesions.
... To the authors' knowledge, ectopic choroid plexus has not been reported in Beagle dogs, although it has been rarely reported in humans (Ha et al. 2014) and horses (Baker and Ellis 1981). Sato et al. (2012) reported a similar lesion in the brain of Beagle dogs and called it "hamartoma in the callosal sulcus." They characterized this finding as a rare lesion that consisted of choroid plexus components (epithelia, fatty tissue, abundant collagen fibers, and small vessels), although they considered the finding to be ectopic tissue. ...
Microscopic examination of the brain of adult Beagle dogs from four different general toxicity studies revealed the presence of ectopic choroid plexus tissue in six individual dogs (4 females and 2 males) with ages ranging from 12 to 18 months. In each dog, this finding was characterized by a well-circumscribed mass localized to a region above and along the corpus callosum without any apparent compression of adjacent brain tissue. Each mass was composed of columnar ependymal cells forming tubular structures surrounded by variable amounts of fibrovascular connective tissue and had the appearance of small rests of ependymal cells that had been penetrated by the leptomeninges during neural development. There were no associated clinical signs or macroscopic correlates. Based on morphologic appearance, a diagnosis of spontaneous ectopic choroid plexus with secondary sclerosis was made. To the authors’ knowledge, ectopic choroid plexus has not been reported in Beagle dogs and is rare in humans and horses.
