Canine ocular neoplasia: a review

Clinical descriptive and long-term outcome of melanocytic uveal lesions in young dogs: 40 cases (45 eyes) including 13 cases of sector iridectomy

PURPOSE

To describe the clinical features surgical technique, early and long-term outcome with or without surgery, and histopathological findings of melanocytic anterior uveal lesions in young dogs.

METHODS

Medical records of dogs at a guide dog facility removed from training due to a pigmented iris lesion were reviewed from 2014 to 2021. Selected dogs had surgical iridectomies performed.

RESULTS

Iridal melanocytic lesions were characterized as well-delineated, pigmented, and flat (nevus) or raised (mass) lesions of the iris. Forty dogs (18 Labrador retrievers, 18 German shepherd dogs, 1 Golden retriever, 3 Labrador/Golden mixes) ranging from 0.5 to 3.1 years of age were affected unilaterally (n = 35) or bilaterally (n = 5). Sector iridectomy was performed in 13 dogs with prominent and well-isolated mass lesion and enucleation was carried out in 2 dogs with extensive lesions, while all other cases were monitored without surgical intervention. Postoperative complications included dyscoria (13/13), focal posterior synechia (9/13) and focal nonprogressive cataract (8/13). All eyes remained visual and comfortable up to 6.2 years post-iridectomy with no clinically identifiable local recurrence. Histopathology was consistent with uveal melanocytoma in all samples obtained surgically. All cases that did not undergo surgery remained free of complications up to 4.5 year post diagnosis.

CONCLUSION

Melanocytic anterior uveal lesions may be overrepresented in certain lineages of breeds and be present at a young age. While none of the eyes developed complications when monitored without surgery, early surgical excision of the mass by sector iridectomy yields noteworthy functional outcome and retention of a comfortable globe.

Challenges in diagnosing canine spindle cell tumours using immunohistochemistry, illustrated by three nonpigmented malignant cases from the nictitating membrane

BACKGROUND

Nonpigmented malignant spindle cell tumours of the membrana nictitans are rare in dogs. In twenty-three years only three cases have been diagnosed in Scandinavia. This study describes the three cases of malignant tumours of the membrana nictitans recorded by the Eye Pathology Section, University of Copenhagen, Denmark, with reference to the clinical appearance and work-up, the treatment and prognosis, and the histopathological description including immunohistochemistry. The three cases are compared to previous publications on canine tumours of the nictitating membrane. We emphasize the importance of using protocols that are adapted to the specific species such as dogs. Opposite the human tissue responses, we even need more than one marker when diagnosing melanomas in dogs.

RESULTS

The dogs presented were an 8-year-old Dachshund, a 12-year-old Akita and a 14-year-old Shetland Sheepdog. All three dogs were entire females. All three nictitating membrane tumours developed on the right nictitating membrane as firm or multilobulated hyperaemic masses. Two of the tumours were macroscopically nonpigmented, the third being partly pigmented on the surface and ulcerated. According to the histopathology and for two of the cases immunohistochemistry with dog-adapted protocols the diagnoses included one hemangiosarcoma and two amelanotic melanomas. Tumour regrowth developed in all three cases and repeated resections were completed 1, 2 and 3 times, respectively, with recurrence experienced within 1.5 months - 3 years.

CONCLUSIONS

Nonpigmented malignant spindle cell tumours of the canine membrana nictitans are rare. Treatment of choice should be complete excision with a minimal histologic tumour-free distance and in case of a recurrence a full resection of the nictitating membrane. We strongly recommend a dog-adapted protocol for immunohistochemistry.

Outcomes of Treatment of Eyelids and Third Eyelid Tumours in Dogs Using High-Frequency Radiowave Surgery

In human ophthalmology, the benefits of using high-frequency radiowave (HFR) electrocautery for surgical procedures were demonstrated and include effective haemostasis, shorter surgery times, and rapid recovery. In canine eyelid surgery, intraoperative bleeding is a common feature that may obscure the surgical field view and lead to the increased swelling of adjacent tissues, bruising, and pain. To evaluate the efficacy and benefits of HFR electrocautery in canine eyelid and third eyelid surgery, the medical records of 48 surgical excisions of eyelid tumours (involving up to one-third of the eyelid length) and 4 third eyelid excisions were reviewed. The information was collected including the breed, age, clinical signs, HFR power setting and mode of the surgical unit, electrode used for the surgery, intraoperative complications, histopathological diagnosis, and postoperative outcomes. Surgical techniques were performed using the Surgitron Dual 3.8 MHz Frequency RF device (Ellman International, Oceanside, NY, USA). Intraoperative bleeding was recorded as absent or very mild, and the surgical procedures were very fast. No complications occurred during the procedures. Healing within 10 days was observed in all the dogs. No tumour recurrences were recorded at the 12-month follow-up. HFR electrosurgery proved to be a safe, effective, and easy-to-perform technique for the removal of eyelid and third eyelid tumours in dogs.

Upregulated MYC expression and p53 mutations may contribute to the oncogenesis of canine Meibomian gland carcinomas

Sebaceous carcinomas of the human ocular adnexa commonly exhibit pagetoid spread, mutations in tumor-suppressor genes, and protooncogene copy number gain. Sebaceous carcinomas are rarely reported in other species, and while the Meibomian gland (MG) represents the most common ocular adnexal structure of the canine eyelid to develop neoplasia, most are clinically and histologically benign. The objective of this study was to compare molecular features of canine MG carcinomas and adenomas. Two retrospectively identified MG carcinomas were subject to immunohistochemistry and qPCR. When compared with normal glands, MYC was upregulated in benign and malignant MG neoplasms. Aberrant p53 expression was restricted to the nuclei of intraepithelial neoplastic cells in MG carcinomas. Adipophilin expression was diminished in MG neoplasms compared with the normal MG. Our findings, if confirmed in a larger cohort of cases, could suggest that MG oncogenesis in a dog may exhibit similar molecular features as their human counterparts.

Hereditary Eye Diseases in German Shepherd Dog

Hereditary eye diseases occur to varying degrees in all dog breeds. Individual purebred breeds have specific predispositions to various eye disorders. The German Shepherd is diagnosed mainly with chronic superficial keratitis/pannus, but also with: distichiasis, plasmoma/atypical pannus, corneal dystrophy, persistent pupillary membranes, cataract, cone degeneration, retinal dysplasia, optic nerve hypoplasia/micropapilla, and limbal melanoma. Individual ocular abnormalities are manifested by characteristic clinical manifestations and ophthalmological findings. Some eye diseases can lead to blindness, others affect the comfort of life or work use of the dog to varying degrees. A thorough knowledge of individual ocular pathologies in a particular breed leads not only to the identification of the diagnosis but also to the correct assessment of the dog’s breeding usability.

Bulbus Destruction by Choroidal Melanocytoma in a Dog: A 3-Year History

A 3-year-old male Slovak Hound with retinal detachment was presented. The causative intraocular mass was detected by ultrasonography, and the course of the disease was monitored over a 3-year period. Enucleation was performed due to secondary glaucoma. A benign choroidal melanocytoma was diagnosed by histopathology. To our knowledge, this is the first report that describes the disease over such a long period of time. The mild course of the disease questions enucleation of eyes with no or minor symptoms. Conventional treatment may be a suitable alternative to surgery for dogs with high anesthesia risks.

Retrospective evaluation of canine primary, multicentric, and metastatic intraocular neoplasia

OBJECTIVE

To provide an updated characterization of the prevalence of primary, multicentric, and metastatic intraocular tumors in the canine patient.

PROCEDURES

Medical records databases from 4 veterinary referral hospitals were reviewed from 1999 to present to identify dogs with a diagnosis of intraocular neoplasia histopathologically confirmed following enucleation or necropsy.

RESULTS

One hundred seventy-two dogs with 173 intraocular neoplasms met the inclusion criteria. Primary intraocular neoplasms were the most common tumors in the study (128); the two most common types were melanocytic neoplasia (90), followed by iridociliary neoplasia (33). There were 28 cases of intraocular involvement secondary to round cell neoplasia, with 18 cases of lymphoma, seven histiocytic sarcomas, and three undifferentiated round cell neoplasms. There were 17 cases of metastatic intraocular neoplasia, with hemangiosarcoma being the most common (9).

CONCLUSIONS

The majority of intraocular tumors in dogs arise from the ocular tissues. However, the eye may also be involved in patients with multicentric neoplasia, and, less commonly, as a site for metastatic disease. Ocular screening for patients with multicentric neoplasia should be considered during staging, and ocular signs should be viewed with suspicion in dogs with neoplasia in other sites.

Canine Intrapelvic Hemangiosarcoma in 12 Dogs (2000–2019): a Retrospective Case Series

Intrapelvic hemangiosarcoma (IP HSA) is an uncommon primary location of canine HSA, and its presentation appears to be different than that of other intra-abdominal HSA locations. The objectives of this study were to report on the clinical presentation, diagnostic options, and clinical outcomes of dogs with IP HSA. Medical records from two veterinary teaching hospitals between 2000 and 2019 were reviewed for dogs diagnosed with IP HSA. Inclusion criteria consisted of a cytologic or histopathologic diagnosis of HSA from a mass arising from the muscles of the pelvic canal. Exclusion criteria included masses arising from organs within the pelvic canal, including the urethra, prostate, and urinary bladder. Twelve dogs were ultimately included in the study. Clinical presentation of IP HSA was varied, with clinical signs including hindlimb lameness, urethral obstruction, and evidence of hemoperitoneum. The median progression free survival was 92 days (range: 1–1057 days). The overall survival time was 165 days (range: 1–1170 days). IP HSA is an underreported location of canine HSA with similar biologic behavior and outcome compared with visceral HSA. It serves as an important differential in patients presenting with new-onset lameness and urethral obstruction.

Current Therapeutics and Future Perspectives to Ocular Melanocytic Neoplasms in Dogs and Cats

Neoplasms of melanocytic origin are diseases relevant to dogs and cats' ophthalmic oncology due to their incidence, potential visual loss, and consequent decrease in life quality and expectancy. Despite its non-specific clinical presentation, melanocytic neoplasms can be histologically distinguished in melanocytomas, which present benign characteristics, and malignant melanomas. The diagnosis often occurs in advanced cases, limiting the therapeutic options. Surgery, cryotherapy, radiotherapy, photodynamic therapy (PDT), and laser are currently available therapeutic strategies. As no clinical guidelines are available, the treatment choice is primarily based on the clinician's preference, proficiency, and the owner's financial constraints. While surgery is curative in benign lesions, ocular melanomas present a variable response to treatments, besides the potential of tumour recurrences or metastatic disease. This review presents the currently available therapies for ocular melanocytic neoplasms in dogs and cats, describing the therapeutic, indications, and limitations. Additionally, new therapeutics being developed are presented and discussed, as they can improve the current treatment options.

Clinical, advanced imaging data and outcome of inflammatory and neoplastic orbital disease in 81 dogs and 16 cats in Australia (2010-2019)

OBJECTIVE

To characterize the clinical presentation, advanced imaging features, and outcome of orbital disease in a referral population of dogs and cats that underwent computed tomography (CT) or magnetic resonance imaging (MRI).

ANIMALS STUDIED

Client-owned animals.

PROCEDURES

Animals referred for orbital disease undergoing ophthalmic examination and either head MRI or CT were included. Demographic and imaging features were compared between animals diagnosed with inflammatory disease and neoplastic disease using Mann-Whitney U and Fischer's exact tests.

RESULTS

Ninety-seven animals (81 dogs and 16 cats) were included. Eighty-four and 13 patients underwent CT and MRI scanning, respectively. Inflammatory orbital disease was more frequently detected than neoplasia in dogs (59% vs. 41%) and cats (62% vs. 39%). Orbital cellulitis was the most common diagnosis in dogs (36/81, 44.4%) and cats (8/16, 80%). A foreign body was suspected in 36.1% of dogs with orbital cellulitis but only 3 were retrieved during orbitotomy. Multi-drug resistant bacteria were identified in 3 samples and influenced treatment plans. The most common neoplasms were sarcoma (10/30) and carcinoma (7/30) in dogs and lymphoma in cats (3/6). Imaging findings of osteolysis (p = 0.0002) and intracranial extension (p = 0.0001) were significantly associated with neoplasia in dogs. In contrast, osteolysis extension was present in cats with both inflammatory (7/10) and neoplastic (6/6) orbital disease.

CONCLUSIONS

Inflammatory disease, particularly orbital cellulitis, was more common than neoplasia in dogs and cats with orbital disease in our population. We recommend including bacterial culture and susceptibility as part of the diagnostic work up when orbital cellulitis is suspected.

Evaluation of eye melanoma treatments in rabbits: A systematic review

Melanomas are the most common cancer of the eye in canines, felines and humans. The treatment approaches vary, since no gold standard exists. Therefore, this systematic review aimed to compare the treatment modalities in ocular melanoma in rabbits. Medline/PubMed, Cochrane Library, Web of Science and Embase were searched for articles published until 21 April 2021 in English, Portuguese or Spanish, reporting animal studies evaluating photodynamic therapy (PDT), laser, radiotherapy or surgical excision. Twenty-seven articles were included for the qualitative synthesis, with publication dates from 1970 to 2018. Of the selected studies, 19 used PDT, six used radiotherapy and two used laser as treatment. No studies regarding surgical therapy that met the inclusion criteria were obtained. The tumour therapy results were evaluated in a heterogeneous manner for different periods and various methods, including microscopy, angiographic, histological examination, fundoscopy, ultrasound exam and electroretinogram. The treatment modalities analysed successfully treated the ocular melanoma, with tumour necrosis being commonly observed. Despite the therapeutic efficacy shown, side effects have been reported for all the therapies. The studies showed high heterogeneity, and therefore, in the future, new studies should be carried out to increase knowledge about ocular melanoma treatment. The analysed therapies can be used successfully in the treatment of ocular melanoma, with more conservative options such as PDT presenting great potential.

Choroidal neuroendocrine neoplasia in a dog

OBJECTIVE

To report onset and progression of clinical signs of a neuroendocrine neoplasm (NEN) presumed metastatic to the choroid in a dog.

ANIMALS STUDIED

A 7.5-year-old female spayed German shepherd dog mix referred for advanced imaging and evaluation of a subretinal mass in the right eye.

PROCEDURES

Procedures performed included general physical and ophthalmic examinations; ocular, orbital, and abdominal ultrasonography; thoracic radiographs; cranial magnetic resonance imaging; serologic testing for infectious agents; analysis of hematologic as well as serum and urine biochemical parameters; echocardiography; electrocardiography; cytologic assessment of lymph nodes; and histopathology and immunohistochemistry of the enucleated globe.

RESULTS

Examination and imaging identified a pigmented mass within and expanding the superior choroid. Following enucleation, a choroidal NEN with tumor emboli in scleral blood vessels was diagnosed by histopathologic assessment and confirmed by immunohistochemical labelling. Despite extensive and repeated diagnostic testing over many months, a putative primary site was not identified until 19 months after the initial ocular signs were noted. At that time, a heart-base mass and congestive heart failure were highly suggestive of a chemodectoma.

CONCLUSION

This comprehensive report of a NEN presumed metastatic to the choroid in a dog suggests that ocular disease can be a very early and solitary sign of NEN in the dog.

Canine Primary Corneal Fibrosarcoma - Case Report

This is the first report of a primary corneal fibrosarcoma in a canine. A 4-year-old male dog, Blue Heeler, owas examined because of a reddish nodular mass in the right eye. A complete ophthalmic exam was conducted, including slit-lamp biomicroscopy, applanation tonometry, fundoscopy, ocular and abdominal ultrasound, hemogram, serum biochemistry profile, and a thoracic X-ray. After the ophthalmic evaluation of the right eye, conjunctival hyperemia and the presence of a .5 cm diameter mass was found in the cornea. The diagnosis of fibrosarcoma was confirmed by histopathological analysis. The keratectomy showed satisfactory results in the removal of the corneal fibrosarcoma. The patient was followed up on for 18 months after the surgical procedure, and there were not any signs of local recurrence or metastasis.

Choroidal melanocytic tumors in dogs: A retrospective study

OBJECTIVE

To describe clinical features of dogs diagnosed with choroidal melanocytic tumors at a veterinary teaching hospital.

ANIMALS STUDIED

Retrospective case series of 13 dogs (14 melanocytic tumors) with choroidal melanocytic tumors.

PROCEDURES

Medical records of dogs evaluated by the Cornell University ophthalmology service with a clinical diagnosis of a choroidal melanocytic tumor between 2008 and 2020 were reviewed. A choroidal melanocytic tumor was clinically defined as any well-demarcated, raised pigmented choroidal lesion underlying the retina. Histopathology results were consulted when available. Signalment and clinical features were recorded, including fundoscopic location, histopathologic findings, treatment, and outcome.

RESULTS

Choroidal melanocytic tumors were identified in 14 eyes of 13 dogs. The mean (±standard deviation) of dogs was 8.6 (±3.5) years. Seven different breeds were represented, with Labrador/Labrador mix being the most common. Ten of the 14 melanocytic tumors were diagnosed incidentally. Four dogs presented for vision loss and ocular discomfort, and diagnosis was made on histopathology examination following enucleation. Pulmonary metastasis was suspected in one dog with an incidentally found choroidal melanocytic tumor OD. Fundoscopic location was available for 8 melanocytic tumors, with 6 (75%) located in the tapetal fundus. Histopathologic diagnosis was melanocytoma for 3 and malignant melanoma in 1 globe, with optic nerve head invasion in 50%. Local recurrence was not seen in any orbit following enucleation.

CONCLUSION

Choroidal melanocytic tumors are uncommon in dogs. Metastasis appears to be rare and was only suspected in one dog, but intraocular tumor growth can lead to retinal detachment, glaucoma, and necessitate enucleation.

Ophthalmopathologic characterization of multicentric or metastatic neoplasms with an extraocular origin in dogs and cats

OBJECTIVE

To characterize the frequency and distribution of secondary ocular neoplasms in dogs and cats identified during necropsy.

METHODS

A retrospective analysis of necropsy records of dogs and cats was conducted, and cases with metastatic/multicentric neoplasms with an extraocular origin, involving the eyes, were selected.

RESULTS

From January 2015 to January 2019, we identified a total of 233 dogs and 100 cats with metastatic disease. Of these, 11.6% (27/233) of the dogs and 13% (13/100) of the cats had ocular metastases. Lymphoma was the most common multicentric neoplasm involving the eyes of both species. In dogs, these neoplasms occurred bilaterally, predominantly in the anterior uvea, and were diffuse large B-cell, T-lymphoblastic, peripheral T-cell not otherwise specified, and lymphocytic B-cell lymphomas. In cats, feline leukemia virus (FeLV)-associated T-cell lymphoma was the most common. Mammary carcinoma was the second most common ocular metastatic neoplasm in bitches, with a predominantly unilateral involvement of the uveal tract. In cats, following lymphoma, pulmonary and squamous cell carcinomas were the most common multicentric/metastatic neoplasms of the eyes. Individual cases of cholangiocarcinoma, hemangiosarcoma, and chemodectoma in dogs, as well as mammary gland cribriform carcinoma, salivary gland carcinoma, and histiocytic sarcoma in cats were detected.

CONCLUSIONS

The eyes of dogs were mostly affected by lymphoma or mammary gland carcinoma, while those of cats mostly had lymphoma, pulmonary carcinoma, or squamous cell carcinoma as the main metastatic/multicentric neoplasm. To the best of our knowledge, this is the first study to identify intraocular metastatic cholangiocarcinoma and chemodectoma in dogs, aside from identifying salivary gland carcinoma in cats.

The investigation of histopathology and locations of excised eyelid masses in dogs

Background

Eyelid masses are the most common ocular diseases in dogs. However, there are no studies specifically investigating the location of eyelid masses.

Methods

118 dogs with 119 eyelid masses were included. Medical records and pathology reports were retrospectively reviewed at National Taiwan University veterinary hospital and Vision Eyecare Centre for Animals between 2012 and 2017.

Results

Mean age of dogs was 9.4±2.5 years. Female spayed dogs had significantly higher prevalence of eyelid mass than female intact dogs (p<0.01). Prevalence of upper eyelid mass was significantly higher than lower eyelid mass (p<0.01). The upper lateral eyelid was the significantly more common location compared with the upper medial eyelid. Mean mass volume was 258.2±661.0 mm³. The most common eyelid mass type was meibomian epithelioma (34.5%), followed by meibomian adenoma (29.4%) and meibomian hyperplasia (18.5%). Non-tumours comprised 25.2%, benign tumours comprised 67.2% and malignant tumours comprised 7.6% of all eyelid masses. Malignant tumours were significantly larger than benign lesions (p<0.01). All dogs underwent surgical excision without any complications.

Conclusion

The majority of eyelid masses were benign. Surgical intervention can prevent further ocular irritation and provide good prognosis.

Post-traumatic Intraocular Leiomyosarcoma in a Domestic Bovine Calf (Bos primigenius taurus)

The present report describes a case of a post-traumatic ocular leiomyosarcoma in a calf (Bos primigenius taurus) including clinical, histopathological and immunohistochemical features. Following a traumatic episode, the animal developed opacification of the lens and shrinkage of the eye. Subsequently, the ocular lesion increased in size over a period of 6 weeks and reached up to 16 cm in diameter with infiltration into the cranium. At necropsy examination, the kidneys, liver and spleen exhibited multiple firm white metastases up to 2 cm in diameter. The mass was composed of closely-packed streams and bundles of neoplastic cells, which immunohistochemically expressed vimentin and alpha smooth muscle actin. Based on the anamnestic data, morphological appearance, distribution and immunohistochemical results, a diagnosis of a post-traumatic intraocular leiomyosarcoma was made. The tumour may have originated from cells lining the pectinate ligament of the ciliary body.

Highly invasive and poorly differentiated corneal squamous cell carcinoma in a dog

BACKGROUND

Primary corneal tumors are unusual in dogs although there has been a rise in the prevalence of canine corneal squamous cell carcinoma in the past decades due to different factors. Exposure to ultraviolet radiation, presence of chronic keratitis or history of superficial trauma are some of them. We report for the first time a highly infiltrative corneal neoplasia with both exophytic and deep stromal growth, which presented atypical histologic features of a squamous cell carcinoma.

CASE PRESENTATION

An adult male French bulldog was referred with an exophytic, pink to white gelatinous mass occupying approximately 70% of the central cornea on the right eye. Histological findings from the excisional biopsy were consistent with corneal carcinoma and transconjunctival enucleation was performed at the request of the owner. A final diagnosis of primary corneal squamous cell carcinoma was done based on the squamous differentiation observed in the neoplastic cells of the superficial layers. However, cells in deeper layers were less differentiated, showed pseudoacinar formations and did not expressed marker for stratified squamous epithelium (i.e., cytokeratin 5/6). The dramatic thickening of the cornea and the fact of observing neoplastic cells almost at the level of the Descemet's membrane make this case very unusual as the squamous cell carcinoma in dogs tends to involve the superficial stroma or colonize the corneal surface as an exophytic lesion.

CONCLUSIONS

Based on the histological findings, a high infiltrative and poorly differentiated corneal squamous cell carcinoma was diagnosed. In terms of clinical relevance, our results suggest that corneal lesions compatible with neoplasia need an early diagnosis in order to prevent the aggressive growth of the tumor and the enucleation of the eye.

Retrospective evaluation of canine palpebral masses treated with debulking and cryotherapy: 46 cases

PURPOSE

To evaluate the recurrence frequency and the time to recurrence of canine palpebral masses treated with debulking and cryotherapy.

METHODS

Medical records of dogs that underwent debulking and cryotherapy for palpebral masses from December 2010 to November 2015 at the University of Minnesota's Veterinary Medical Center were reviewed. A telephone survey with owners was used to determine recurrence and time to recurrence.

RESULTS

Forty-six masses (31 dogs) were included in this retrospective study. Included palpebral masses were as follows: adenomas 17/46 (37%), epitheliomas 8/46 (17.4%), papillomas 6/46 (13%), inflammatory masses 6/46 (13%), mixed adenoma-papillomas 6/46 (13%), mixed epithelioma-papillomas 2/46 (4.4%), and a melanocytoma 1/46 (2.2%). Of the seven masses that were noted to recur (7/46, 15.2%), three were mixed adenoma-papillomas (three of six adenoma-papillomas, 50%), two were epitheliomas (two of eight epitheliomas, 25%), one was a papilloma (one of six papillomas, 16.7%), and one was a melanocytoma (one of one melanocytoma, 100%). Average recurrence time was 367.9 days [range: 30-904 days]. A significant association between tumor type and tumor recurrence was found (P = .009). Adenomas were significantly less likely to recur (P = .017), and mixed adenoma-papillomas were significantly more likely to recur (P = .001).

CONCLUSIONS

Debulking and cryotherapy is an effective method of treatment for eyelid masses in dogs with a low study recurrence rate of 15.2% and average recurrence time of 367.9 days. Results also suggest that mixed adenoma-papilloma masses have a significantly higher recurrence rate than other eyelid masses, whereas adenomas had no recurrence in our study population.

Caracterização clínica e histopatológica de bulbos oculares de cães e gatos (2005-2015)

RESUMO: Objetivou-se realizar a caracterização clínica e histopatológica de bulbos oculares de cães e gatos, removidos cirurgicamente por indicação clínica, no período entre 2005-2015. Foram realizados 101 procedimentos de remoção do bulbo ocular, 93 enucleações (92%) e 8 exenterações (8%). Os procedimentos foram realizados em 80 cães, (79% dos casos) e em 21 gatos (21% dos casos). Os cães submetidos à intervenção cirúrgica apresentavam perfurações oculares (n=31, 39%), glaucoma (n=19, 24%), protrusão ocular (n=13, 16%), diagnósticos sugestivos de neoplasia (n=10, 12,5%) e outros (n=3, 2,97%). Dentre os gatos os diagnósticos clínicos compreenderam perfuração ocular (n=9, 49%), glaucoma (n=3, 14,2%), microftalmia (n=3, 14,2%), sugestivo de neoplasia (n=2, 9,5%), protrusão ocular (n=2, 9,5%) e outros (n=2, 9,5%). Vinte e sete amostras de bulbos oculares foram submetidas para avaliação histopatológica, sendo 23 provenientes de cães e quatro de gatos. Dentre as amostras de origem canina, sete exibiram achados histopatológicos compatíveis com glaucoma, sete perfurações oculares, seis neoplasias intraoculares, duas panoftalmites e um quadro de Phthisis bulbi. Nos bulbos oculares de gatos foram diagnosticadas duas neoplasias intraoculares, uma microftalmia e uma perfuração ocular. Constatou-se que o glaucoma secundário, as neoplasias e as perfurações oculares estão entre as principais causas de enucleação em cães, e associadas a alterações primárias como a ceratoconjuntivite seca e as uveítes. Estas afecções, diferentemente das neoplasias, podem ter êxito terapêutico mediante diagnóstico e tratamento precoces, prevenindo a cegueira e a remoção do bulbo ocular.

Angioceratoma conjuntival canino: relato de caso

RESUMO O angioceratoma é um tumor de origem vascular, semelhante ao hemangioma, que se diferencia deste por alterações histológicas epiteliais. A apresentação ocular do angioceratoma é pouco frequente em cães, sendo mais comum a ocorrência de hemangioma e hemangiossarcoma. Neste relato, é descrito o caso de um cão, macho, da raça Border Collie, que apresentava uma massa localizada, hiperêmica, bem vascularizada e protrusa, na região temporal da conjuntiva bulbar do olho direito (OD). Foi realizado exame oftalmológico completo e ultrassonografia ocular, tendo sido possível observar que a massa não envolvia outras estruturas oculares além da conjuntiva. Dessa forma, foi realizada a conjuntivectomia parcial, e o material foi encaminhado para análise histológica. O exame histopatológico foi conclusivo para um angioceratoma e mostrou que as margens da amostra estavam livres. O procedimento cirúrgico com margem de segurança foi eficiente no tratamento da neoplasia, sem recorrência até o momento do presente relato.

Recurrence after exenteration for canine orbital malignant schwannoma

A 14-year-old Maltese dog presented with progressive exophthalmos and external deviation of the right eye. Ultrasonography revealed the presence of a retrobulbar mass and fine-needle aspiration cytology was performed, which detected a malignant mass. There was no evidence of metastasis on thoracic and abdominal radiography. Computed tomography showed no invasion into the bony orbit and no metastasis to the lung or lymph nodes. Exenteration was performed to remove the mass completely. Malignant peripheral nerve sheath tumor was confirmed by histopathological examination.

Optic nerve astrocytoma in a dog

Intracranial astrocytomas are relatively uncommon in dogs and optic nerve astrocytomas even more so. This neoplasm should be considered as differential in canine patients with vision loss, retinal detachment, ocular mass, and histopathologic findings of infiltrative fusiform to polygonal glial cells possibly associated with glomeruloid vascular proliferation.

Histiocytic chorioretinitis in a dog

A 3-year-old castrated male mixed-breed dog presented with an acute bullous retinal detachment and thickened choroid of the right eye. Subretinal cytology revealed an atypical cell proliferation suggestive of neoplasia. The eye was enucleated, and the original diagnosis was a histologically benign choroidal melanocytic tumor. Further diagnostics revealed no other systemic abnormalities other than a nonhealing shoulder wound. Six months later, the left eye developed a bullous retinal detachment. This eye responded well to systemic steroids and the dog regained vision within a few weeks of initiating therapy. Results of immunohistochemistry with Melan-A and CD204 of the previously enucleated right eye caused a revision of the histologic diagnosis from melanocytic tumor to histiocytic chorioretinitis. This case highlights the subtle and sometimes confusing distinction between neoplastic and inflammatory processes on both cytology and histopathology.

Melanocytic Ophthalmic Neoplasms of the Domestic Veterinary Species: A Review

Melanocytic neoplasms in veterinary species occur in various ophthalmic locations including the eyelid, conjunctiva, cornea, sclera, anterior and posterior uvea, and orbit. Histology usually provides the definitive diagnosis for melanocytic ocular neoplasias. The degree of tissue invasiveness and anaplastic cellular characteristics are more reliable indicators of biological behavior than is mitotic index in most ophthalmic melanocytic tumors. Melanocytic neoplasias of the eyelid are predominantly benign in canines and equines, though in felines, there is the potential for metastasis, especially if the conjunctiva is involved. Limbal melanocytic tumors are predominantly benign in all the studied species, though there is a bimodal occurrence with this tumor type in canines, where those that appear in dogs younger than 4 years tended toward active growth, whereas those that appear in dogs older than 8 years tended to progress more slowly, and may not require therapy. The most common location for melanocytic ocular neoplasias in both canines and felines is the anterior uvea. Feline diffuse iris melanoma in particular has a higher incidence of metastasis than does canine nodular anterior uveal melanocytoma. In contrast, posterior uveal melanocytic tumors are rare in both canine and feline species and are considered benign. Orbital melanoma is rare in both canine and feline species; however, it generally carries a grave prognosis owing to its malignant nature. Knowledge of the general biological behavior and its variability among locations within the eye and between species is essential in therapeutic planning.

Malignant peripheral nerve sheath tumor of the third eyelid in a 3-year-old Rhodesian Ridgeback

A 3-year-old Rhodesian Ridgeback was presented with conjunctivitis, enlargement of the third eyelid and a dorsotemporal deviation of the right eye. A mass within the third eyelid was detected and excised. The histopathologic examination showed a malignant peripheral nerve sheath tumor, which most likely is a neurofibrosarcoma based on immunohistochemistry.

A case of primary choroidal malignant melanoma in a cat

This report describes the clinical presentation, diagnosis, histological lesions, and prognosis of a primary choroidal malignant melanoma in a 15-year-old cat. The animal was presented for unilateral blindness. On ocular examination, a raised pigmented mass protruding from the posterior pole into the vitreous body was observed by diffuse transillumination and indirect ophthalmoscopy. Ocular ultrasound and computer tomography (CT) scan confirmed localization of the tumor to the posterior segment. The diagnosis of primary choroidal melanoma was confirmed by histopathology after enucleation. To our knowledge, this is the first reported case of a feline malignant melanoma with a primary choroidal localization without iris involvement.