Canine multiple primary tumours: Mammary tubular carcinoma, uterine leiomyosarcoma, and facial sebaceous epithelioma.

Multiple primary malignant tumours (MPMTs) are multiple neoplasms with independent pathogenetic origins, placing great importance on the tumorigenesis and clinical treatment. However, due to the rare occurrence and diagnostic confusion, MPMTs have rarely been investigated in veterinary medicine. In this report, a 10-year-old intact female Maltese dog had MPMTs, consisting of two malignant tumours and one benign tumour each derived from a topographically different site: tubular carcinoma in the mammary glands, leiomyosarcoma in the uterus and sebaceous epithelioma in the cheek. The unique combination of MPMTs would be the first case in veterinary research to give insight into the diagnosis, disease characteristics, and surgical treatment.

Dermoscopic features of benign sebaceous proliferations in dogs: Description, assessment and inter-observer agreement.

BACKGROUND: Dermoscopy is a useful, noninvasive technique also used to assess sebaceous lesions in humans. Sebaceous hyperplasia, sebaceous adenoma and sebaceous epithelioma are common cutaneous lesions in dogs; however, their dermoscopic features have not been investigated. HYPOTHESIS/OBJECTIVES: The objectives of this study are to describe the dermoscopic features of canine sebaceous lesions and to assess the interobserver agreement on dermoscopic parameters. ANIMALS: Thirty-four lesions excised from 17 client-owned dogs, histologically confirmed as sebaceous proliferations, were included in this study. MATERIALS AND METHODS: Sebaceous lesions were evaluated in vivo at ×10 magnification with a handheld dermoscope. Each dermoscopic image was assessed independently by two ECVD board-certified veterinary referral clinicians and an ECVD resident. RESULTS: Thirty sebaceous hyperplasias, two sebaceous adenomas and two sebaceous epitheliomas were included. Dermoscopically, most lesions (91%) had single or multiple, well-defined, white-yellowish structures composed of grouped ovoid areas (clods). Irregular linear and, less commonly, arborising vessels were detected at the periphery of the yellow lobular-like structures in 93% of sebaceous hyperplasias and in 50% of neoplastic lesions. Erosions were seen in 6% of sebaceous hyperplasias and 50% of neoplastic lesions. Good interobserver agreement was found for white/yellowish clods (k = 0.75), yellow scales (k = 0.83), brown/grey dots (k = 0.80), erosions (k = 0.82) and red/brownish scales/crusts (k = 0.75). There was moderate agreement for fissures (k = 0.48) and vascular pattern (k = 0.51-0.53). CONCLUSIONS AND CLINICAL RELEVANCE: Dermoscopy represents a useful technique to assess sebaceous gland proliferations in dogs, as it is in humans.

Muir-Torre syndrome (MTS): An update and approach to diagnosis and management.

Muir-Torre syndrome (MTS) is a rare genetic condition that predisposes individuals to skin tumors and visceral malignancies. Because of the potentially aggressive nature of internal malignancies and sebaceous carcinoma, and the tendency to have multiple low-grade visceral cancers, close cancer surveillance is required in individuals and their families with this usually autosomal dominant disorder. Although the majority of MTS is caused by mutations in DNA mismatch repair genes resulting in microsatellite instability, a newly described subtype of MTS does not demonstrate microsatellite instability and may be inherited in an autosomal recessive pattern. In addition, MTS may be unmasked in transplant recipients taking specific immunosuppressant drugs or other immunosuppressed patients. Neoplasms may be subject to immunohistochemistry or both immunohistochemistry and genetic testing to confirm the diagnosis of MTS. Here, we offer an update and an approach to the diagnosis and management of MTS with a particular emphasis on the role of immunohistochemistry and genetic testing.

RETROSPECTIVE EVALUATION OF CASES OF NEOPLASIA IN A CAPTIVE POPULATION OF EGYPTIAN FRUIT BATS (ROUSETTUS AEGYPTIACUS).

Reports of neoplasia in Chiroptera species are rare. (6, 10) This retrospective study describes five types of neoplasia identified within a captive population of male Egyptian fruit bats (Rousettus aegyptiacus) housed in a zoo from 2004 through November of 2014. Tumor types identified include fibrosarcoma, cutaneous lymphoma, benign focal bronchioloalveolar neoplasm, anaplastic sarcoma, and sebaceous epithelioma. To the author's knowledge, aside from a recent report of focal brochioloalveolar adenoma, (8) these tumor types have not previously been described in the Rousettus species, nor in chiropterans in general. Based upon these findings and other recent publications regarding R. aegyptiacus, neoplasia does appear to be a significant cause of morbidity and mortality in captive members of this megachiropterid species.

Aquaporin 3 is expressed in the basaloid cells of canine sebaceous glands.

The role of aquaporin proteins (AQPs) in tumor biology has attracted attention over the past 20 years. However, the expression profiles of AQPs in canine sebaceous gland tumors remain obscure. This study was performed to clarify the expression of AQP1, 3, 5, the most studied AQPs in tumor biology, in sebaceous adenoma and sebaceous epithelioma. Among these AQPs, only AQP3 was expressed in normal tissue and both tumor types and located to only undifferentiated sebocytes (basaloid cells). A cellular proliferation marker, Ki-67, was detected only in the area including basaloid cells in both tumor types. These findings suggest that AQP3 is useful for clarifying the origin of sebaceous gland tumors, and that AQP3 may be related to sebaceous gland development.

Intraductal sebaceous papilloma of a meibomian gland: a new entity possibly associated with the MSH6 subtype of the Muir-Torre syndrome.

Over several months, a painless, multinodular, non-erythematous swelling of the deep tissues of his left upper eyelid developed in a 63-year-old man. An excisional biopsy with histopathologic evaluation disclosed a unique sebaceous papilloma within a cyst lined by non-keratinizing squamous epithelium that focally displayed a variably thick, superficial, eosinophilic cuticular layer. Immunohistochemical staining demonstrated that the tumor and its epithelial cystic lining had a profile consistent with Meibomian gland duct epithelium. Adipophilin highlighted cytoplasmic vacuolar lipid positivity. The encapsulation of the lesion, absence of nuclear atypia, and Ki-67 nuclear positivity restricted to the basilar cells established its intrinsically benign nature. The patient's clinical history was remarkable for pulmonary and colonic carcinomas resected, respectively, 20 years and 8 years earlier. DNA mismatch repair protein expression studies disclosed loss of nuclear immunostaining of MSH6 protein, pointing to the possibility of an underlying rare MSH6 variant of the Muir-Torre syndrome, not yet described in the ophthalmic literature. p16 nuclear positivity was also found in the tumor cells, indicating the possible role of high-risk human papillomavirus as an additional factor in the genesis of the tumor. Genetic evaluation of normal and tumoral tissues in future similar cases will detect if there is an underlying germline mutation versus a somatic mutation limited to the tumor. This will be required to fully establish a predictable linkage with this new subtype of the Muir-Torre syndrome.

Benign Sebaceous Epithelioma with Carcinoid-like Trabecular Cell Arrangement.

A case of 75-year-old woman with sebaceous epithelioma was reported. The histological features were distinct in that it had a sinusoidal and carcinoid-like growth pattern, which has been reported in its malignant counterpart. Immunostaining for adipophilin was positive in the area with lipid-laden vacuolated cells, but the rest of tumor, which had cord-like nests, was negative. MIB index was 2%. CK5/6 and p40 were positive in the cord-like nesting areas. CK7, CK20, alpha SMA, and epithelial membrane antigen were negative in both the cord-like nesting areas and the adipose-like areas. The tumor was diagnosed as sebaceous epithelioma with a trabecular pattern. Dermatopathologists should be aware of this atypical histological pattern of benign sebaceous epithelioma.

Intra-oral Sebaceous Gland Tumours in Two Dogs.

A 12-year-old female miniature schnauzer and a 12-year-old neutered female cocker spaniel each had a grey-yellow nodular lesion arising from the gingiva. Microscopical examination showed that both nodules were composed of varied proportions of sebocytes and basal-type reserve cells with few ducts lined by stratified squamous epithelium. Based on the histopathological findings, the cases were diagnosed as sebaceous adenoma and sebaceous epithelioma, respectively. In man, the occurrence of sebaceous neoplasms in the oral cavity has been reported to some extent, but these lesions are very rare in animals. To the best of our knowledge, this is the first report of intra-oral sebaceous neoplasms in dogs. Intra-oral sebaceous epithelioma has never been reported in animals.

Immunohistochemical characterization of sebaceous epithelioma in two dogs.

This report describes two cases of sebaceous epithelioma and its immunohistochemical characterization with CK 14, CK18, p63, Ki67 and Bcl-2 immunostaining. Case 1 was a 12-year-old, intact English Cocker spaniel female presenting with multiple skin nodules over one year. Case 2 was a 7-year-old, spayed poodle female with a five-month history of solitary mass. Hematoxylin and eosin (H&E) staining showed that the nodules in both cases were irregular lobules comprised of epithelial cells around well-differentiated sebocytes. Neoplastic cells were positive for CK14 and p63 but were negative for CK18 cell marker. In addition, immunostaining for Ki67 proliferation marker showed 13.1% and 12.4% positive cells in the two cases, respectively. Furthermore, Bcl-2, which is highly expressed in human benign sebaceous tumors, was seen in basaloid cell nuclei and cytoplasm. CK14, CK18, p63, Ki67, and Bcl-2 antibody application provided further information for diagnosing sebaceous epithelioma and for prognosis in these two cases.

Histopathological findings and proliferative activity of canine sebaceous gland tumours with a predominant reserve cell population.

Sebaceous gland tumours represent the third most common skin tumours in dogs, but diagnostic criteria for tumours with basal differentiation (i.e. sebaceous epithelioma) are poorly defined and there is lack of correlation with biological behaviour. The aim of this study was to identify the main histological criteria associated with malignancy in 30 canine sebaceous gland tumours with a predominant reserve cell population. For each case, tumour proliferative activity was assessed by determining mitotic index and the Ki67/MIB-1 index. Additional histological features included endophytic or exophytic growth, proportion of reserve/intermediate/mature cells, connection to the epidermis, nuclear characteristics, peripheral invasion, neoplastic emboli and necrosis. Mitotic and Ki67 indexes were variable, but correlated (R = 0.66; P < 0.001), and both were significantly higher in infiltrative tumours (P = 0.018 and P < 0.001, respectively). No significant difference in histological features was observed between tumours comprised of more or less than 90% reserve cells, nor among tumours showing proliferative activity in sebocytes. This study suggests that high proliferative activity and peripheral invasion should be considered the most significant parameters for the differentiation between benign and malignant sebaceous gland tumours. Furthermore, the incidence of circumanal gland and testicular tumours in these dogs was significantly higher compared with an age-matched control population, suggesting a potential androgen-related pathway for the tumourigenesis of canine sebaceous gland neoplasms.

Sebaceomas: a propósito de dos casos / Sebaceomas: report of two cases

Los sebaceomas son tumores infrecuentes que se originan en los anexos sebáceos. Suelen desarrollarse en adultos mayores, más frecuentemente en cabeza y cuello. Su denominación es controversial, presentando características histopatológicas y clínicas similares a otras entidades, que presentan diferenciación sebácea. El pronóstico de esta entidad es bueno, siendo su tratamiento la extirpación quirúrgica. Sin embargo, su relevancia clínica se establece por su asociación frecuente con el síndrome de Muir-Torre, por lo que ante la presencia de esta neoplasia, es necesario descartar neoplasias viscerales ocultas. Presentamos el caso de dos pacientes con sebaceomas en diferentes localizaciones, que hasta el momento de esta publicación no presentaron síndrome de Muir-Torre asociado y realizamos una revisión de la literatura.

Sebaceomas are infrequent tumors originated from the sebaceous annexes. They usually develop in the third decade, more frequently in the head and neck. Its denomination is controversial, presenting both histopathological and clinical characteristics similar to other entities, with sebaceous differentiation. The prognosis of the condition is good, being its treatment the surgical removal. Though, its clinical relevance is established by its frequent association with the Muir-Torre syndrome, so that, in the presence of this neoplasm, it is necessary to rule out occult visceral neoplasms. We present two cases of sebaceomas in different locations that until this moment did not present associated neoplasm.

A Case of Eyelid Sebaceoma Mimicking Chalazion

PURPOSE: To report a rare case of sebaceoma misdiagnosed as chalazion. CASE SUMMARY: A 42-year-old female presented with a visible mass in her right lower eyelid. An elevated, hard mass was located at the margin of the right lower eyelid, and she had a history of incision and curettage under the clinical impression of chalazion. On eversion of the lower eyelid, the tarsal portion of the mass was visible as a white-yellowish lesion. The mass was excised under local anesthesia. A sebaceoma was diagnosed based on histopathological examinations. Immunohistochemical studies showed positive staining results for mutator L homologue 1 (MLH1), mutator S homologue 2 (MSH2), and mutator S homologue 6 (MSH6), and she had no past medical history or family history of internal malignancy, suggesting a low possibility of Muir-Torre syndrome. CONCLUSIONS: Eyelid sebaceoma should be considered as a differential diagnosis for refractory chalazion.

A Case of Sebaceoma on the Right Earlobe / 대한피부과학회지

Sebaceoma, also known as sebaceous epithelioma, is a rare, benign, adnexal tumor with sebaceous differentiation. It usually appears as a yellowish papule, nodule, or plaque on the scalp and face, on which there are abundant sebaceous glands. Histologically, it is a well-circumscribed lesion composed of undifferentiated basaloid cells and mature sebaceous cells in relatively preserved lobulated architectures. A 31-year-old woman presented with a 1.3-cm ×1.1-cm nodule on the right earlobe. Mohs micrographic surgery was performed to completely remove it. Histopathological examination revealed that mature sebaceous cells with scalloped nuclei and focal cystic change were present in the lobule.

A Giant Sebaceous Epithelioma on the Scalp: A Case Report

PURPOSE: Sebaceous epithelioma (sebaceoma) is a benign tumor with sebaceous differentiation. It presents primarily as a yellowish papule or nodule on the face and scalp. It must be differentiated from basal cell carcinoma and other appendageal tumors. We report a giant sebaceous epithelioma on the scalp and describe the immunohistochemical character of the cells in sebaceous epithelioma to epithelial membrane antigen (EMA). METHODS: A 55-year-old-man who presented with 5-cm-diameter 2-cm-height, round shape exophytic ulcerated tumor on his head presented for treatment. The patient had noticed the lesion 40 years prior as a small yellowish plaque and 18 months ago, the plaque started to grow progressively larger. We excised the lesion with 1 cm resection margin, considering the possibility of malignancy because this lesion grossly resembled basal cell carcinoma (BCC). The defect was repaired with the use of a split-thickness skin graft. RESULTS: When we excised the lesion, the margin was clear. Histology showed nodules that consisted of an admixture of basaloid cells and mature adipocytes lacking an organized lobular architecture. Strong expression of EMA on mature adipose cells confirmed the differential diagnosis from BCC with sebaceous differentiation because of the absence of a nuclear palisade pattern and cleft-like spaces on the hematoxylin and eosin (H&E) section. CONCLUSION: We treated the giant sebaceous epithelioma on the scalp with surgical excision and a split-thickness skin graft. It is important to know that the diagnosis of sebaceous epithelioma should be made based on the histologic pattern of the H&E section. Immunohistochemistry with EMA can help to confirm the differential diagnosis between sebaceous epithelioma and BCC.

A Giant Sebaceous Epithelioma on the Scalp: A Case Report

PURPOSE: Sebaceous epithelioma (sebaceoma) is a benign tumor with sebaceous differentiation. It presents primarily as a yellowish papule or nodule on the face and scalp. It must be differentiated from basal cell carcinoma and other appendageal tumors. We report a giant sebaceous epithelioma on the scalp and describe the immunohistochemical character of the cells in sebaceous epithelioma to epithelial membrane antigen (EMA). METHODS: A 55-year-old-man who presented with 5-cm-diameter 2-cm-height, round shape exophytic ulcerated tumor on his head presented for treatment. The patient had noticed the lesion 40 years prior as a small yellowish plaque and 18 months ago, the plaque started to grow progressively larger. We excised the lesion with 1 cm resection margin, considering the possibility of malignancy because this lesion grossly resembled basal cell carcinoma (BCC). The defect was repaired with the use of a split-thickness skin graft. RESULTS: When we excised the lesion, the margin was clear. Histology showed nodules that consisted of an admixture of basaloid cells and mature adipocytes lacking an organized lobular architecture. Strong expression of EMA on mature adipose cells confirmed the differential diagnosis from BCC with sebaceous differentiation because of the absence of a nuclear palisade pattern and cleft-like spaces on the hematoxylin and eosin (H&E) section. CONCLUSION: We treated the giant sebaceous epithelioma on the scalp with surgical excision and a split-thickness skin graft. It is important to know that the diagnosis of sebaceous epithelioma should be made based on the histologic pattern of the H&E section. Immunohistochemistry with EMA can help to confirm the differential diagnosis between sebaceous epithelioma and BCC.

Muire-Torre syndrome: A case of sebaceous epithelioma with thyroid cancer / 대한내과학회지

Muir-Torre syndrome (MTS) is an autosomal dominant genodermatosis characterized by at least one rare sebaceous neoplasm occurring in association with at least one internal malignancy. The visceral neoplasms most frequently associated with MTS are colorectal and genitourinary cancer, accounting for approximately 50 and 25% of cases, respectively. MTS rarely occurs in association with head and neck cancers. We report a rare case of MTS involving follicular thyroid carcinoma in an 84-year-old female.

Muire-Torre syndrome: A case of sebaceous epithelioma with thyroid cancer / 대한내과학회지

Muir-Torre syndrome (MTS) is an autosomal dominant genodermatosis characterized by at least one rare sebaceous neoplasm occurring in association with at least one internal malignancy. The visceral neoplasms most frequently associated with MTS are colorectal and genitourinary cancer, accounting for approximately 50 and 25% of cases, respectively. MTS rarely occurs in association with head and neck cancers. We report a rare case of MTS involving follicular thyroid carcinoma in an 84-year-old female.

A Case of Nevus Sebaceus, Accompanied by Syringocystadenoma Papilliferum, a Basal Cell Carcinoma-like Tumor, Sebaceous Epithelioma, Apocrine Adenoma and Tumor of Follicular Infundibulum, with Repair by Subgaleal-periosteal Fixation / 대한피부과학회지

Nevus sebaceus is well-known for its potential to develop both benign and malignant neoplasms of epidermal and adnexal origin. We found 5 tumors including syringocystadenoma papilliferum, a basal cell carcinoma-like tumor, sebaceous epithelioma, a tumor of follicular infundibulum and apocrine adenoma within a single nevus sebaceus lesion in a 37-year-old man. This is a rarely reported case of a nevus sebaceus lesion containing a basal carcinoma-like, trichoblastoma-like skin tumor and tumors of follicular infundibulum. The lesion was treated by wide excision and repaired with subgaleal-periosteal fixation which resulted in good wound healing.

A Case of Sebaceous Epithelioma / 대한피부과학회지

Sebaceous epithelioma is a rare skin appendage tumor with sebaceous differentiation and appears as yellow papules, nodules, or plaques, most commonly in areas with large numbers of sebaceous glands, such as the face. Histopathologically, sebaceous epitheliomas are composed of circumscribed nodules consisting predominantly of basaloid cells and foci of sebaceous differentiation. We report a case of sebaceous epithelioma which appeared as a yellowish to erythematous patch on the forehead in a 55-year-old woman.