Investigation of extragonadal teratomas in two Poecilia wingei.

Teratoma is a rare tumour in fish consisting of tissues from more than one germ layer, that may be located in either the gonads or extragonadal sites. Teratomas in many fish species remain poorly understood. In this work, we performed the first histological examinations of extragonadal teratomas in Poecilia wingei and also examined the influence of a large teratoma on male sexual activity. The studied teratomas shared general organizational features, but they also had variations in both external and internal features. In teratomas, the most common and highly differentiated tissues were striated muscle and nervous tissue. Despite the tumour, the male P. wingei exhibited normal mating behaviour and retained the ability for successful copulation. The structural features of extragonadal teratomas in guppy fish indicate a possible connection between these tumours and a failure of conserved processes operating in the embryonic germline.

Computed tomographic findings in a canine ovarian teratoma.

A 2-year-old, intact female, Labrador Retriever was referred for progressive abdominal distension, assessed by emergency clinicians as being extrauterine in origin on AFAST. Abdominal radiographs and ultrasound identified a large, lobulated, partially mineralized, soft tissue, mid-abdominal mass and gravid uterus. Contrast-enhanced CT identified a mixed fat to soft tissue attenuating mass with a complex internal mineralized matrix, heterogeneous contrast enhancement, receiving blood from the left ovarian artery. Histology confirmed a left ovarian teratoma, diffuse endometrial hyperplasia, and fetal implantation. The patient had a good post-operative outcome for 2 years, but was later diagnosed with primary cranial mediastinal neuroendocrine carcinoma.

A spontaneous ovarian teratoma in an FVB/n female mouse: Case report and literature review.

Background: Teratomas are rare types of germ cell neoplasms composed of various differentiated or undifferentiated tissues. Case Description: A 25-week-old female control FVB /n mouse in a 4-week toxicity study presented abdominal distension and poor body condition. It was euthanized, and the necropsy examination revealed a large mass connected to the tip of the right uterine horn, occupying the entire abdominal cavity. Microscopically, this mass showed areas of epidermal differentiation, with laminated keratin and sebaceous glands, differentiation into respiratory and digestive epithelium, cartilage, bone, and extensive areas of differentiation into the nervous tissue, being classified as an ovarian teratoma. Conclusion: As far as authors know, the occurrence of ovarian teratomas in the FVB/n mouse strain has never been previously described.

Clinical and ultrasonographic findings of ovarian tumours in bitches: A retrospective study.

A retrospective study was carried out to investigate incidence, clinical signs and ultrasonographic findings of ovarian tumours in a population of dogs referred to the Veterinary Teaching Hospital of the University of Perugia (Italy) and Anicura Tyrus Veterinary Clinic (Terni, Italy). The period of study ranged from January 2005 to December 2021. A total of 1910 dogs were affected by neoplasia but only 35 of them (1.8%), of different breeds and ages, were found to have ovarian tumours. Ultrasound of the ovaries was performed based on clinical signs; the diagnosis was achieved after ultrasound findings prompted ovariohysterectomy and ovarian pathologic evaluation In our study, the age of bitches affected by ovarian neoplasia ranged from 3 to 20 years (mean 9.6 ± 3.8). The histopathological findings of ovarian masses identified 16 granulosa cell tumours (GCT) (46%), 7 adenomas (20%), 5 adenocarcinomas (14%), 2 teratomas (6%), 1 leiomyoma (3%), 1 luteoma (3%), 1 tecoma (3%), 1 dysgerminoma (3%), and 1 haemangiosarcoma (3%). In particular, with respect to clinical signs, 69% of bitches showed abnormalities of estrus cycle (short interestral interval, persistent estrus, prolonged interestral interval). The other main clinical signs included abdominal distention, palpable abdominal mass, vulvovaginal discharge, polyuria/polydipsia, mammary masses. When present, the laboratory abnormalities were slight anemia and leucocytosis with neutrophilia. The tumours were ultrasonographically classified as mainly solid: 12/35 (34%) (1 adenoma, 4 adenocarcinomas, 1 dysgerminoma, 1 haemangiosarcoma, 1 leyomioma, 1 luteoma, 1 GCT, 1 tecoma, 1 teratoma); solid with cystic component 13/35 (37%) (9 GCT, 2 Adenomas, 1 adenocarcinoma, 1 teratoma); and mainly cystic 10/35 (29%) (6 GCTs, 4 adenomas). In our study, the ultrasound examination allowed us to suspect ovarian neoplasia in asymptomatic subjects referred for breeding management or for preventive health check. On the basis of our data, we proposed to perform a complete periodic examination of the reproductive system once a year from 6 years. Nevertheless, the presence of ovarian neoplasms found in young subjects, during breeding management, suggest including routine ultrasound examination of the reproductive tract.

A case of immature teratoma with nephroblastic components in the oral cavity of a cat.

A 2-month-old female mixed cat was emaciated due to dysphagia, and inspection of the mouth revealed a 2 cm pedunculated mass elongated from the palate, which occupied the oral cavity. The mass was surgically removed, and histopathological examination revealed that the tumor was composed of three germ cell layers: ectodermal (skin and skin appendages), mesodermal (cartilaginous and osseous structures), and endodermal (glandular and respiratory mucosa) tissues. An immature teratoma was diagnosed because of the presence of immature neuroectodermal tissues, and the presence of nephroblastic components was a characteristic finding in this case. This is the first report of an oropharyngeal teratoma in cats and the first case of an immature teratoma with nephroblastic components in a domestic species.

Clinical, sonographic and anatomopathological aspects of ovarian teratoma in a heifer / Aspectos clínicos, ultrassonográficos e anatomopatológicos do teratoma ovariano em uma novilha

Teratomas rarely occur in domestic species, especially in cattle. These tumors originate in fetal life and are characterized by rapid growth, which justifies their frequent detection in young animals. This study reported a case of ovarian teratoma in a heifer. On physical examination, the main signs identified were apathy, abdominal distention and tension, empty rumen, and mushy diarrhea. During rectal palpation, a mass was identified in the pelvic region, which was suggestive of cysts on ultrasound examination. The animal underwent laparotomy, followed by euthanasia due to a poor prognosis. At necropsy, a 54 x 43 x 52 cm (length x width x thickness) tumor was observed in the right ovary with multiple cystic areas, in addition to masses associated with multiple adhesions of the intestinal loops and peritonitis. On histopathology, muscle, cartilage, bone, nervous and epithelial tissue, glands, hair with follicles, were identified in the affected ovary. There was mixed inflammation and foci of necrosis observed with a complete absence of ovarian architecture in both the ovaries. Infiltrations were identified in the lymph nodes and mesenteric vessels. Glandular ducts were seen from the serosa to the intestinal mucosa. A locally infiltrative and expansile ovarian teratoma was diagnosed accordingly. It is considered that this kind of tumor can induce abdominal distension and absence of estrus in previously healthy, non-pregnant heifers.

Os teratomas são tumores raros nas espécies domésticas, sobretudo em bovinos. Esses tumores são caracterizados por crescimento rápido e origem durante a vida fetal, o que justifica seu diagnóstico frequente em animais jovens. O presente trabalho relata um caso de teratoma ovariano em uma novilha. No exame físico, os principais sinais identificados foram apatia, distensão e tensão abdominal, rúmen vazio e diarreia pastosa. Durante a palpação retal, uma massa foi identificada na região pélvica. Ao exame ultrassonográfico, a massa era sugestiva de cistos. O animal foi submetido a laparotomia, seguido de eutanásia devido ao mau prognóstico. Na necropsia foi observado um tumor de 54 x 43 x 52 cm (comprimento x largura x espessura) no ovário direito com múltiplas áreas císticas, além de massas associadas à múltiplas aderências das alças intestinais e peritonite. Na histopatologia foram identificados no ovário acometido a presença de tecidos muscular, cartilaginoso, ósseo, nervoso e epitelial, com glândulas, pelos e folículos. Havia inflamação mista e focos de necrose com ausência completa de arquitetura ovariana em ambos os ovários. Infiltrações foram identificadas em linfonodos e vasos mesentéricos. Ductos glandulares foram vistos desde a serosa até mucosa intestinal. Diagnosticou-se um teratoma ovariano localmente infiltrativo e expansivo. Considera-se que este tumor pode induzir distensão abdominal e ausência de estro em novilhas previamente sadias e não gestantes.

Successful surgical management of massive ovarian teratoma in a rhesus macaque (Macaca mulatta).

A 5 years-old Rhesus macaque was presented with abdominal enlargement. The clinical, radiographic and ultrasonographic findings suggested that a massive mass occupying the whole of the abdomen. The mass was surgically removed, and histopathology confirmed ovarian teratoma. The macaque recovered uneventfully; however, the management to avoid self-mutilation of skin sutures was challenging.

Intracoelomic Teratoma in an Eclectus Parrot (Eclectus roratus).

A 26-year-old, male eclectus parrot (Eclectus roratus) was presented to its primary care veterinarian for a 10-day history of increased respiratory effort, lethargy, and a single episode of regurgitation. Hepatomegaly, proventricular enlargement, cranial displacement of the ventriculus, and coelomic effusion were suspected based on a 1-view radiographic image, and the patient was referred for further evaluation. On presentation to the referral veterinary hospital, a distended coelom and dyspnea with abnormal respiratory sounds were abnormalities noted upon physical examination of the patient. The bird was hospitalized for supportive care, and diagnostic tests were performed. Initial radiographic images at the referral hospital revealed a large intracoelomic mass. A computed tomographic scan was performed; however, the origin of the mass could not be determined. A fine-needle aspirate and cytologic evaluation of the intracoelomic mass revealed a neoplastic process but no specific tissue type. Two days after presentation to the referral hospital, an exploratory coeliotomy to surgically resect the mass was attempted. The mass occupied most of the coelomic cavity, with multiple adhesions to internal organs. The mass was successfully resected; however, the patient destabilized and died despite resuscitation efforts. Histopathologic examination of submitted tissue from the mass with immunohistochemistry revealed mixed populations of neoplastic cells differentiated from 3 primordial germinal layers, confirming the diagnosis of teratoma. Teratomas appear to be a rare tumor in avian species but should be included in a list of differential disease diagnoses for abnormal tissue masses of unknown origin. Only 2 cases of teratomas have, to our knowledge, been reported in psittacine species.

Squamous metaplasia of the rete ovarii do not suppress ovarian cyclicity and pregnancy in cattle: case report / [Metaplasia escamosa da rete ovarii não interrompe a ciclicidade ovariana e a gestação em bovinos: relato de caso]

Squamous metaplasia of the rete ovarii is an ovarian pathologic change characterized by replacement of the normal single layered cuboidal epithelium of the rete ovarii by a stratified squamous keratinized epithelium. Uterus and ovaries from a local slaughterhouse pregnant crossbreed cow were evaluated through ultrasound, macroscopically and histologically. Grossly, there were multiple cysts in both ovaries, which were histologically characterized as rete ovarii cysts with squamous metaplasia and intraluminal accumulation of keratinized material. Squamous metaplasia of the rete ovarii has been previously reported in cows, however this is the first report of this condition in a pregnant animal, demonstrating that this ovarian change is compatible with pregnancy.(AU)

A metaplasia escamosa da rete ovarii é uma patologia ovariana caracterizada pela substituição do epitélio simples cuboidal normal da rete ovarii por um epitélio estratificado escamoso queratinizado. Útero e ovários de uma vaca mestiça gestante, proveniente de abatedouro, foram avaliados por ultrassonografia, macroscopia e histologia. Verificaram-se vários cistos em ambos os ovários, histologicamente caracterizados como cistos de rete ovarii com metaplasia escamosa, com acúmulo intraluminal de material queratinizado. Metaplasia escamosa da rete ovarii foi relatada anteriormente em vacas, porém este é o primeiro relato em que essa alteração ovariana é compatível com manutenção da ciclicidde ovariana e gestação na vaca.(AU)

Ovarian mixed germ-cell tumor comprising mature teratoma and embryonal carcinoma in a four-toed hedgehog (Atelerix albiventris).

This report describes the clinical and histopathological characteristics of a rare mixed germ-cell tumor comprising teratoma and embryonal carcinoma in the left ovary of a 10-month-old four-toed hedgehog, with chief complaints of loss of appetite and lethargy. Laparotomy revealed a swollen left ovary with small disseminated peritoneal nodules, and bilateral ovariohysterectomy was performed. The left ovary had a mature teratoma with well-differentiated fat, bone, cartilage, salivary gland, trachea, keratin cyst, and nervous tissues, and an embryonal carcinoma consisting of poorly-differentiated epithelial cells arranged in tubular, alveolar, or solid patterns. Immunohistochemically, the embryonal carcinoma cells were positive for placental alkaline phosphatase and c-KIT. This is the first case of mature teratoma with embryonal carcinoma in the ovary of a hedgehog.

Brain teratoma in a free-ranging mallard (Anas platyrhynchos) - case report / [Teratoma cerebral em um pato-real (Anas platyrhynchos) de vida livre - relato de caso]

Teratoma is a rare neoplasia with differentiation in two or three germ cell lines. Intracranial teratoma in birds has rarely been reported, especially affecting the brain. This is the first report of a brain teratoma in a mallard with neurological clinical signs. The neoplasm was characterized as a mature brain teratoma, extending from the cerebellum to the brainstem, and with one nodule in the cortex.(AU)

O teratoma é uma neoplasia rara, com diferenciação em duas ou três linhagens de células germinativas. Teratomas intracranianos, em aves, são raramente relatados, principalmente, com localização cerebral. Este é o primeiro relato de teratoma cerebral em um pato-real com sinais clínicos neurológicos. A neoplasia foi caracterizada como um teratoma cerebral maduro, estendendo do cerebelo ao tronco encefálico e com um nódulo no córtex.(AU)

Testicular Teratocarcinoma in a Ferret (Mustela putorius furo).

A 7-month-old male domestic ferret (Mustela putorius furo) was presented for evaluation of unilateral testicular enlargement. Microscopic examination of the left testicle revealed a neoplasm with differentiation along multiple cell lines (ectoderm, endoderm, mesoderm) including respiratory epithelium, bone and haired skin. A poorly differentiated epithelial component was dispersed throughout the neoplasm with invasion of testicular lymphatics. The animal developed progressive dysuria and was euthanized. At necropsy, metastasis of the poorly differentiated epithelial component was present in the urinary bladder, ureters, prostate gland, pelvic fat, abdominal and thoracic lymph nodes, kidney and lung. This is the first report of a malignant testicular teratoma with widespread metastasis in this species.

Metastatic Ovarian Teratocarcinoma in a Horse.

A 3-year-old Quarter Horse mare presented with an approximate 1-month history of progressive weight loss, anorexia and lethargy that abruptly worsened 48 h before death. Post-mortem examination revealed free flocculent fluid and a large mass within the ventral abdomen that dorsally displaced the caecum and large intestine. An ovarian teratocarcinoma with metastasis to regional lymph nodes was diagnosed histologically. Although benign teratomas are the second most common ovarian neoplasm in equids, reports of malignant teratomas in horses are rare. This report documents an unusual presentation of a rarely reported malignant neoplasm of the reproductive tract in horses.

Ovarian teratoma in a woodchuck (Marmota monax) with hepatocellular carcinoma: radiologic and pathologic features.

BACKGROUND: Teratomas are germ cell neoplasms composed of a wide variety of tissues. In the woodchuck, only one testicular teratoma has been described in the literature. The objective of this report was to describe the radiologic and pathologic findings in a female woodchuck (Marmota monax) with an ovarian teratoma consisting of mature tissues originating from all three germ layers. CASE PRESENTATION: A 2-year-old female woodchuck that had been infected at birth with woodchuck hepatitis virus and subsequently developed hepatocellular carcinoma was incidentally discovered to have a mobile 6.6 × 4.8 × 4.7 cm abdominal mass on computed tomography (CT) imaging. The tumor was predominantly solid and heterogenous on CT with soft tissue, fat, and areas of dense calcification. The teratoma did not enhance with intravenous contrast administration. On ultrasound, the tumor was solid with heterogeneous echogenicity, reflecting the fat content and areas of calcification. Sonolucent areas were present that may have represented cysts. There was heterogeneously increased signal on T1-weighted magnetic resonance imaging (MRI) and heterogeneous hyperintensity in T2-weighted imaging. Fat was evident within the tumor. At necropsy, the tumor was attached to the distal end of the right uterine horn. Histopathology showed mature tissue types representing all three germ layers. CONCLUSIONS: Ovarian teratoma should be considered in the differential diagnosis of ovarian or abdominal masses in woodchucks. The tumor displayed mature tissue derived from all three germ layers. CT, ultrasound, and MRI findings were presented in detail and matched the typical imaging appearance of teratomas.

Teratoma Associated With Testicular Tissue in a Female-Like Horse With 64,XY (SRY-Positive) Disorder of Sex Development.

A four-year-old female-like Quarter Horse was admitted for clinical evaluation because of masculinized-aggressive behavior and lack of estrous signs. On external inspection, a hypertrophied clitoris and prominent muscles were observed. On gynecological examination, apparently normal mammary glands, vulva, vagina, and cervix were noted. On the other hand, the uterus had no tone and was smaller than normal. The left gonad was very soft on palpation and the right gonad was mostly firm, irregular, and wider than the left gonad. On ultrasound examination, there were no signs of regular ovarian structure or follicular activity. Because of the different shapes and consistencies of the gonads and a suspicion of increased testosterone production, a bilateral gonadectomy was recommended. Blood was collected for testosterone levels quantification and for cytogenetic and molecular investigations. After removal, gonads were analyzed macroscopically and sections were sent for histopathological examination. A final diagnosis of benign adult teratoma associated with seminiferous tubules and Leydig cells was made. On cytogenetic and molecular analyses, a normal diploid number of 64 chromosomes and the presence of the XY sex chromosomes were seen in all cells, as well as the SRY gene. Testosterone levels were higher than normal before surgery and were reduced after gonads removal. In conclusion, the masculinized behavior was probably caused by increased testosterone levels produced by testicular tissue, in a female-like horse with 64,XY SRY-positive disorder of sex development, which was associated with a teratoma.

Extragonadal malignant teratoma in a dog - case report / Teratoma extragonodal maligno em cão - relato de caso

Teratomas are neoplasms thought to arise from germ cells which usually occur within gonads and are rarely described on extragonadal sites. The present study reports a case of a 15 year old female mongrel dog with a lumbosacral tumor. The tumor was microscopically composed of embryonic tissues with areas containing atypical undifferentiated cells, leading to the diagnosis of a malignant teratoma. Malignant teratomas are uncommon tumors in domestic animals.(AU)

Os teratomas são neoplasias originárias das células germinativas que têm como sítio principal as gônadas; raramente ocorrem em sítios extragonodais. O presente estudo relata um caso de uma cadela de 15 anos de idade, sem raça definida, apresentando aumento de volume na região lombossacral que ao exame microscópico revelou neoformação composta por tecidos de origem embrionária, com áreas indiferenciadas exibindo atipia celular, características compatíveis com teratoma maligno. Teratomas malignos são incomuns em animais domésticos.(AU)

Recurrent Subcutaneous Teratoma in an Adult Red-crowned Amazon Parrot (Amazona viridigenalis).

An approximately 42-year-old, wild-caught, red-crowned Amazon parrot (Amazona viridigenalis) was evaluated for a subcutaneous mass to the right of the keel. Cytologic examination of a fine needle aspirate of the mass were suggestive of granulomatous inflammation. The mass was surgically excised, and the parrot was treated with oral nonsteroidal anti-inflammatory drugs. Histologically, the mass was diagnosed as a teratoma with stratified squamous epithelial and neuroectodermal components. Tumor cells extended to surgical margins. Two years later, the neoplasm recurred, with regrowth of only the neuroectodermal component. The neoplasm was again removed surgically, but it recurred again 14 months later, necessitating a third surgery. Histopathologic examination confirmed recurrence of the original neoplasm in both instances, with incomplete margins on both excisions.

Mixed germ cell tumor composed of a tridermic testicular teratoma and seminoma in a rooster.

A 5-y-old backyard Araucana-Americana rooster was presented to the regional diagnostic laboratory with a history of progressive lethargy and respiratory signs. Autopsy revealed a single large mass of testicular origin in the coelomic cavity, causing compression of other organs. Histologically, the mass was 1 neoplasm with mixed components of 2 different germ cell tumors, namely a teratoma composed of elements of all 3 primordial germ cell lines (ectoderm, mesoderm, and endoderm), and a seminoma consisting of round or polygonal cells arranged in sheets supported by a scant fibrovascular stroma. Teratomas and seminomas are both considered to be uncommon neoplasms in poultry medicine. A testicular teratoma is composed of mature embryonic tissue derived from at least 2 of the 3 germinal layers. Seminomas and teratomas both arise from the germinal epithelium of seminiferous tubules and are classified as germ cell tumors. This neoplastic mass thus is a rare case of a mixed germ cell tumor.

Co-existing monophasic teratoma and uterine adenocarcinoma in a female dog.

Ovarian teratomas are occasionally reported in dogs; the rarest type is the monophasic teratoma, composed of tissues originating from only one germ layer. Canine endometrial adenocarcinomas are also rare in dogs and mainly affect geriatric females. This report describes the case of co-existing ovarian teratoma and uterine adenocarcinoma in a 10-year-old nulliparous female Boxer presented with lethargy, anorexia and purulent vaginal discharge. Abdominal ultrasonography evidenced pyometra and a mass in the left ovary. This was composed of a uniform whitish tissue with multiple cystic structures. The histology revealed an atrophy of the ovarian parenchyma, compressed by a proliferation of well-differentiated nervous tissue staining positively to vimentin, S100 and neuronal specific enolase (NSE), and negatively to keratin and inhibin. The left uterine horn, whose diameter was markedly increased, showed foci of endometrial cellular atypia, evident nucleoli and mitoses, at light microscopy. To our best knowledge, this is the first report of a co-existing ovarian monophasic teratoma and endometrial adenocarcinoma, two rare reproductive neoplasia in dogs.

Bladder teratoma in a maned wolf (Chrysocyon brachyurus).

Background: Teratomas are germ cell tumors, comprised of a mixture of tissue types and with tissue foreign to their site of origin. Case Description: A 5.5-year-old intact female maned wolf (Chrysocyon brachyurus) was treated for recurrent stranguria and suspected cystitis. Due to lack of resolution, the wolf was anesthetized for further evaluation. The urinary bladder was firm on palpation, with a markedly thickened wall and no observable lumen on ultrasound. Neoplastic infiltration was suspected on double contrast cystogram and confirmed via surgical exploration. The lesion was inoperable and the wolf was euthanized. Gross necropsy revealed two poorly distinguished masses infiltrating the urinary bladder dorsally and caudoventrally, with minimal remaining lumen. Histopathologic examination of the bladder and associated masses revealed a neoplasm comprised of multiple tissue types. Vascular invasion was noted. Conclusion: The neoplasm was diagnosed as an extragonadal teratoma. Few extragonadal teratomas have been described and this is the first report of a teratoma originating in the urinary bladder of a non-human species.