Basal cell enumeration does not predict malignancy in canine perianal gland tumor cytology.

BACKGROUND: Perianal (hepatoid) gland tumors are common in dogs, and the distinction between the benign and malignant forms is clinically important. Cytology of these tumors typically contains many large hepatoid cells and fewer small basal cells. OBJECTIVES: The objective of this study was to determine whether the proportion of the smaller basaloid reserve cells in cytologic samples from perianal tumors correlates with malignancy. METHODS: Eighty-three cases of cytologically diagnosed perianal gland tumors with corresponding histopathologic sections were identified from two separate institutions and included six (7.2%) malignant tumors and 77 (92.8%) benign tumors. The proportion of basal cells from each sample was evaluated. RESULTS: No difference between these groups was found, although the study was sufficiently powered to detect an approximately 1.5-fold change in basal cell proportion. CONCLUSIONS: This report found no evidence that the proportion of basal cells in canine perianal tumor cytology is an indication of the potential for malignancy. We, therefore, do not recommend citing this feature in cytologic reports or when communicating with clinicians.

Pruebas epicutáneas en pacientes con eczema perianal / Patch Testing in Patients With Perianal Eczema

INTRODUCCIÓN Y OBJETIVOS: La prevalencia de parches positivos en los pacientes afectados por una dermatitis anogenital oscila según las series entre un 25-78%, justificándose por tanto la realización de pruebas epicutáneas ante eczemas de esta localización. Los objetivos del presente estudio son por un lado determinar los alérgenos más frecuentes en los pacientes con eczema perianal y, por otro, establecer las baterías de alérgenos más útiles para el estudio con pruebas epicutáneas de esta afección. MATERIAL Y MÉTODOS: Se han revisado retrospectivamente (años 2001-2012) los resultados obtenidos al estudiar con pruebas epicutáneas a aquellos pacientes que presentaban exclusivamente un eczema perianal. RESULTADOS: De los 37 pacientes con esta clínica en 16 se observó alguna reacción positiva, siendo el metilcloroisotiazolinona/metilisotiazolinona el principal alérgeno implicado. Excepto un caso con sensibilización a gentamicina, todas las positividades con relevancia presente correspondieron a alérgenos de la batería estándar del Grupo Español de Investigación en Dermatitis de Contacto y Alergia Cutánea (GEIDAC) o a productos propios del paciente. CONCLUSIONES: En nuestra experiencia la metilcloroisotiazolinona/metilisotiazolinona es el principal alérgeno implicado en los eczemas perianales, procediendo esta sensibilización frecuentemente del uso de toallitas higiénicas. El estudio epicutáneo de un eczema perianal deberá realizarse básicamente con la batería estándar y los productos propios

INTRODUCTION AND OBJECTIVES: Reports show that between 25% and 78% of patients with anogenital dermatitis have positive patch test results. Consequently, patch testing would appear to be warranted in patients presenting with eczema in the anogenital region. The objectives of the present study were to identify the most common allergens in patients with perianal eczema and to determine which allergen series are most useful for patch testing in patients with this condition. MATERIAL AND METHODS: We performed a retrospective review of patch test results in patients with only perianal eczema between 2001 and 2012. RESULTS: Of the 37 patients with perianal eczema, 16 had a positive reaction; methylchloroisothiazolinone/methylisothiazolinone was the main allergen involved. With the exception of 1 case of sensitization to gentamicin, all the positive results with present relevance were to allergens from the standard series of the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC) or to the patient's own products. CONCLUSIONS: In our experience, methylchloroisothiazolinone/methylisothiazolinone is the main allergen involved in perianal eczema, and sensitization often results from using wet wipes. Patch testing in perianal eczema should be based on the GEIDAC standard series and the patient's own products

Retrospective--systematic study and quantitative analysis of cellular proliferation and apoptosis in normal, hyperplastic and neoplastic perianal glands in dogs.

Neoplasms in the perianal region are frequently diagnosed in dogs. The aetiology is unknown, and most of them are benign. In this study, 240 neoplasms of the perianal glands of dogs were retrieved from the Department of Pathology archives of the Faculty of Veterinary Medicine and Zootechny of University of São Paulo (FMVZ/USP), from 1984 to 2004. All 240 cases were re-examined by two pathologists. Nine cases (4%) were diagnosed as hyperplasia, 49 (20%) as group I adenoma, 81 (34%) were classified as moderately differentiated adenomas of the group II, 46 (19%) were poorly differentiated adenomas of group II, 48 (20%) were carcinoma of the group III according to the classification proposed by Berrocal, and 7 (13%) were other kind of tumours. Males over 8 years of age were predominantly affected. Cell proliferation was quantified by counting proliferating cell nuclear antigen (PCNA) positive nuclei, and apoptosis was quantified by counting fluorescent eosin-stained apoptotic corpuscles (AC) in normal tissue, hyperplasia and in different histologic types of neoplasia of these glands. A parallel pattern of increase in both parameters (cell proliferation and apoptosis) was obtained. The net growth index (NGI), represents how much a cell population is proliferating or dying and was achieved by dividing the mean PCNA count in 1000 cells by the mean AC stain count in 1000 cells. NGI was different between hyperplasia and neoplasia; group I adenomas have a much higher potential of growth, and NGI decreases from benign towards malignant lesions. These results show up the importance of studying cell proliferation and apoptosis to understand the carcinogenesis of dog perianal gland.

Cytology of subcutaneous glandular tissues.

This article deals with the cytologic appearance of various glandular tissues located in the subcutaneous tissues. Normal cytologic features are described. In addition, inflammatory, infectious, neoplastic, and hyperplastic changes are discussed. Most of these features are depicted in the 60+ photomicrographs that are distributed throughout the article. Many of the changes are similar in the glands, and it is usually possible to differentiate the gland of origin based on cytologic appearances. Subcutaneous neoplasms that are not associated with a subcutaneous gland, and lymph node cytology are not covered in this article but are addressed elsewhere.

[Contradictions in modern data on the structure and function of dog hepatoid circumanal glands]. / Protivorechiia sovremennykh dannykh otnositel'no stroeniia i funktsii gepatoidnykh tsirkumanal'nykh zhelez sobaki.

Since the 1950s, an erroneous viewpoint has gained a foothold in the special and reference literature that dog hepatoid circumanal glands have an abortive nature, lack efferent ducts, and show no signs of secretory activity. Nevertheless, most modern researchers indicate that these glands are actively functioning structures differentiated to exercise some function according to their histological pattern; however, no one has managed to define this function. The latest international publication (Atoji et al., 1998) considers dog circumanal hepatoid glands as a "circumanal body" similar to epidermis rather than glands. We discuss strong and weak points of the data on dogs hepatoid circumanal glands published in 1950s-1990s in comparison with those obtained in our purposeful long-term investigation of various hepatoid glands. We strongly disagree with the viewpoint of Atoji et al. (1998); hepatoid circumanal glands of dog and other canids should be considered as odor glands, their abundant protein secretion covers the skin surface in the circumanal region, it is preserved on fecal marks, and its smell is perceived during mutual nosing of the anal region.

[Once more about hepatoid circumanal glands of dogs. History of their discovery and reasons for revision the structural and functional data]. / Eshche raz o gepatoidnykh tsirkumanal'nykh zhelezakh sobaki. Istoriia ikh otkrytiia i prichiny peresmotra svedenii ob ikh stroenii i funktsii.

In the skin surrounding the anus in dogs and other Canidae, there is a glandular sheet consisting of strongly developed hepatoid glands, as well as single apocrine glands and a certain number of sebaceous glands, which are much smaller and occur less frequently than the hepatoid glands. All three circumanal glands have excretory ducts connecting with the hair bags (hair funnels). The hepatoid glands of some Canidae and Bovidae were extensively studied in the 1920s-1930s, but from the beginning of the 1950s until the present, as a result of the often repeated mistake passing from one book to another, old information about the hepatoid glands was fully lost, while the new information does not answer the question about the function of this complex and well developed structure. We were successful in repeating the data of the discoverers of the hepatoid glands and proved that these glands are exocrine and that their cells excrete protein to intercellular channels and then to ducts and hair funnels. According to the published data, the odor of the secretory substance of the circumanal hepatoid glands is essential for communication in wolves and dogs.

Apocrine sweat glands in the circumanal glands of the dog.

Apocrine sweat glands in the circumanal glands of the dog are not connected morphologically with the lobules of the circumanal glands. However, an apparent functional association has been demonstrated and it is possible that the apocrine sweat glands might serve as excretory ducts for degenerated polyhedral cells of the circumanal glands. In this study, we examined the ultrastructure of the apocrine sweat glands in the circumanal glands of the dog in an effort to define more precisely the relationship between the apocrine sweat glands and the circumanal glands. Paraffin sections stained with azan and sections after immunohistochemical staining with antibodies against actin were examined by light microscopy. Samples fixed by aldehyde perfusion were examined with the electron microscope. Diameters of apocrine sweat glands and height of cells in the secretory epithelium varied considerably. Immunohistochemical staining for actin was weakly positive in the supranuclear regions of secretory cells and very intense in myoepithelial cells. In secretory cells, the endoplasmic reticulum was well-developed. Multivesicular bodies were abundant and were discharged into lumens. Apocrine secretion and exocytosis were observed at luminal surfaces of secretory cells. There were three types of large granule in the cytoplasm: giant mitochondria without cristae; membrane-enclosed globules with or without myelin-like contents; and electron-dense, homogeneous, globular structures. Luminal surfaces were always covered with microvilli, and extensive folding of the cell membrane was found in basal regions. Bundles of actin filaments were dispersed throughout the cytoplasm. In the lumens of apocrine tubules, we observed shed secretory cells with well-preserved normal fine structures. We also noted the differentiation of secretory cells that was due to cell renewal. Apocrine sweat glands in the circumanal glands of the dog appear to be more active than those on the general body surface in terms of apocrine secretion, exocytosis, and the release of multivesicular bodies. Shed secretory cells containing large granules, as well as degenerated polyhedral cells from the circumanal glands, might contribute, to some extent, to the subtle composition of sweat from these apocrine sweat glands.

Circumanal glands of the dog: a new classification and cell degeneration.

BACKGROUND: The circumanal glands of the dog are thought to be a glandular tissue, but there is some controversy as to whether they should be classified as exocrine or endocrine. In this study, we examined the nature of the circumanal glands to determine whether they should be described as exocrine, endocrine, or something else altogether. In addition, we investigated the cell degeneration in lobules of the circumanal glands in relation to the apocrine glands. METHODS: Light microscopic observations were made of paraffin sections stained with hematoxylin and eosin, and after immunohistochemical staining with antibodies against alpha-smooth muscle actin, keratin, filaggrin, and 3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD). Samples were also examined by electron microscopy after fixation by aldehyde perfusion. RESULTS: The lobules of circumanal glands could be divided into two types on the basis of the presence or absence of cysts. Four layers (I-IV) were detected in the lobules with cysts. The outermost layer (layer I or the basal layer) consisted of flattened cells that contained bundles of tonofilaments and were stained immunohistochemically with the antibody against keratin. Layer II (the polyhedral or "spinous" layer) consisted of polyhedral cells that contained bundles of tonofilaments. These cells were connected to adjacent cells by desmosomes, interdigitations, and gap junctions, and they were immunopositive for keratin. A small number of polyhedral cells were immunopositive for 3beta-HSD. Layer III (the granular layer) was composed of flattened cells that contained hematoxylin-stainable granules and were moderately immunopositive for filaggrin. The innermost layer (layer IV or the horny layer) consisted of keratin. Lobules without cysts consisted only of layer I (the basal layer) and layer II (the polyhedral layer). Lobules of the circumanal glands were not directly connected to apocrine glands. Polyhedral cells degenerated and were phagocytosed by basal cells at a periphery of lobules. Then, basal cells phagocytosing degenerated polyhedral cells escaped from lobules, moved into the walls of apocrine glands, and, finally, dropped into the lumen of apocrine glands. CONCLUSIONS: Lobules of the circumanal glands have many characteristics of epidermis (a basal layer, a polyhedral or "spinous layer," a granular layer, and a horny layer) and they should not be classified as glandular tissue. The cysts in lobules can be interpreted as "closed hair canals." We suggest that steroid metabolism might occur in the polyhedral cells of the lobules.

Histological and structural observations on pre-anal glands of the gekkonid lizard, Hemidactylus flaviviridis.

This paper describes a structural and histological study of the pre-anal glands of Hemidactylus flaviviridis. Only males possess these glands, which have a tubulo-acinar structure. They are holocrine in nature and become hyperactive during the breeding period. Thus they may be involved in the production of pheromones for socio-sexual communication.

The microscopic anatomy of epidermal glands in two species of gekkonine lizards, with some observations on testicular activity.

The gross and microscopic anatomy of epidermal glands has been studied in laboratory maintained tokays (Gekko gecko), and house geckos (Hemidactylus bowringii) captured from the wild throughout the year. Annual testicular activity in the house gecko has also been studied. While no significant differences in glandular development at various times have been observed in G. gecko, there are clear-cut annual cycles in H. bowringii. The evolution of epidermal glands in gekkonid lizards is reviewed; the cellular dynamics of beta-glands are compared with those of unspecialized epidermis; the possibility that gekkonine epidermal glands respond to quantitative variation in circulating testosterone titers is discussed.