Chromatophoromas are neoplasms that develop from the dermal pigment-bearing and light-reflecting cells (chromatophores) in the skin of reptiles, fish, and amphibians. Seventeen cutaneous chromatophoromas were identified from 851 bearded dragon submissions (2%) to a private diagnostic laboratory in a 15-y period. No sex predilection was found. Ages ranged from 9 mo to 11 y. Chromatophoromas most commonly were single, raised, variably pigmented masses or pigmented scales on the trunk, and less commonly the extremities or head. Microscopically, iridophoromas, melanophoromas, mixed chromatophoromas, and nonpigmented chromatophoromas were identified. Neoplasms were often ulcerated and invaded deep into the subcutis and muscle. Most commonly, nuclear atypia was mild-to-moderate, and mitotic count was low. Six neoplasms had abundant, periodic acid-Schiff–positive, mucinous stroma. Histologic examination was often adequate to diagnose chromatophoromas in bearded dragons given that 11 of 17 had some degree of pigmentation, although it was often scant. IHC for S100 and PNL2 could be helpful to diagnose poorly pigmented neoplasms. No lymphatic invasion or metastases at the time of excision were noted in any of the cases. Follow-up data were available for 6 cases, with no reports of recurrence or neoplasia-related death. Two cases had elevated mitotic counts and nuclear pleomorphism, which has been associated with metastasis in other reports of bearded dragon chromatophoromas. In general, it appears that aggressive surgical excision is often curative, but monitoring may be warranted for cases in which tumors had high mitotic count and nuclear pleomorphism.

Background Primary hyperaldosteronism caused by adrenal neoplasia has been well described in cats. Multiple corticosteroid abnormalities occur in a subset of affected cats, but characterizations of this syndrome are limited to several case reports. Objectives To describe a series of cats with adrenal tumors secreting aldosterone and additional corticosteroids. Animals Ten cats with multiple corticosteroid secreting adrenocortical tumors. Methods Retrospective case series. Medical records of cats with adrenal tumors secreting both aldosterone and progesterone were identified. Data concerning historical findings, clinicopathologic features, treatments, and outcomes were retrieved from medical records. Results All 10 cats had diabetes mellitus in addition to biochemical features of hyperaldosteronism such as hypokalemia. High corticosterone concentrations were observed in all 3 cats in which this corticosteroid was measured. Ultrasound examinations revealed unilateral adrenal tumors in all 10 cases, and the contralateral adrenal gland was either atrophied or not identified in 5 cats. Three of 4 cats developed hypoadrenocorticism after surgical adrenalectomy. Three cats achieved diabetic remission after adrenalectomy. Two cats treated with adrenalectomy survived >1 year, 1 cat survived 6.5 months, and 1 cat was alive 5.5 months after diagnosis. Survival >1 year occurred in 2 of 4 cats treated with medical management alone. Two cats were not treated. Conclusions and Clinical Importance The presence of multiple corticosteroid abnormalities should be considered in cats with aldosterone secreting adrenal tumors, especially those with concurrent diabetes mellitus. Both surgical and medical management can result in long‐term survival, although diabetic remission was documented only in cats undergoing adrenalectomy.

Background Open angle glaucoma is the only type of primary glaucoma reported in Beagles. This case report describes a primary angle-closure glaucoma in a Beagle and its diagnostic and prognostic relevance. Case presentation A 12-year-old, neutered male Beagle presented to the Michigan State University (MSU) Comparative Ophthalmology Service for evaluation of suspected visual impairment. Complete ophthalmic examination of the left eye (OS) revealed: blepharospasm, absent menace response, moderate episcleral congestion, mild diffuse corneal edema, mydriasis, asteroid hyalosis, decreased myelination and cupping of the optic nerve head, and mild retinal vascular attenuation. Examinations of the right eye (OD) were within normal limits. Intraocular Pressure (IOP) were 24 mmHg OD and 49 mmHg OS. Gonioscopy OD revealed a narrow iridocorneal angle with moderate pectinate ligament dysplasia characterized by broad-based pectinate ligament strands (fibrae latae) and solid sheets (laminae) throughout all 4 quadrants. DNA testing revealed that the dog did not carry the Gly661Arg ADAMTS10 mutation responsible for primary open angle glaucoma (POAG) in Beagles. The OS was medically managed with latanoprost 0.005% and dorzolamide HCl 2% /timolol malate 0.5% ophthalmic solutions for 7 months and then enucleated due to uncontrolled IOP. Histopathologic evaluation was consistent with goniodysgenesis with a broad, non-perforate, sheet-like band of uveal stroma bridging from the base of the iris to the terminal arborization of Descemet’s membrane. Approximately 14 months from the initial diagnosis of glaucoma OS, OD also developed glaucoma and was enucleated. Histopathologic findings were consistent with goniodysgenesis OD. Conclusions To our knowledge, this is the first reported case of PACG with goniodysgenesis in a Beagle supported by clinical, genetic, and histopathologic data. It highlights the importance of gonioscopy in Beagles with glaucoma. Further studies with a larger number of dogs are warranted to characterize clinical manifestations and inheritance of PACG in this breed.

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A renal tubular cystadenoma was diagnosed in a 14-yr-old male African lion (Panthera leo). During a routine health evaluation, a left renal mass was identified via physical examination, radiographs, and abdominal ultrasonography. The mass was 30 × 15 cm in size and had a thin capsule with central hypoechoic fluid, suggestive of a perirenal cyst. An exploratory celiotomy with partial nephrectomy was performed without complications. Histologically, the tumor was characterized by a thick fibrous capsule surrounding multiple, variable-sized cysts that markedly compressed the adjacent fibrotic and atrophied renal cortex. Immunohistochemical labeling for Aquaporin-1 and Tamm-Horsfall protein was consistent with a renal tubular cystadenoma of proximal tubule origin. Renal cystadenomas are an uncommon benign epithelial neoplasm. There are only two documented case reports in domestic cats. This report represents the first documentation, to the authors' knowledge, of a renal cystadenoma in a lion.

Chromatophoromas are neoplasms that arise from pigment cells of reptiles, amphibians, and fish. They include melanophoromas (melanomas), iridophoromas, and xanthophoromas. Most chromatophoromas develop spontaneously, but genetic and environmental factors may also play a role in their oncogenesis. The diagnosis is typically through histologic examination. Immunohistochemistry and electron microscopy can be helpful for diagnosing poorly differentiated and/or poorly pigmented neoplasms. Aggressive surgical excision is the current treatment of choice. This review describes the clinical presentation, gross appearance, diagnostic applications, clinical behavior, and treatment of chromatophoromas in reptiles.

A 5-month-old castrated male Smooth Fox Terrier presented for a 1-month history of right thoracic limb lameness. Physical examination revealed right elbow pain on extension and mild soft tissue swelling of the distal antebrachium. Radiographs and computed tomography showed elongated focal radiolucent regions in the distal radial metaphysis. There was incongruity of the right elbow with a short radius.Bone biopsy and histopathology of the regions confirmed a retained cartilaginous core characterised by bony trabeculae with frequently retained central cartilaginous cores. A dynamic proximal ulnar ostectomy was performed to improve elbow congruity. The owner was instructed to restrict activity to short leash walks for 8 weeks followed by a gradual activity increase. On follow-up examination 16 weeks after operatively, the lameness and elbow pain were resolved. Radiographs at that time showed a healed ulnar ostectomy, proper elbow congruity, and resolved retained cartilaginous core.

We diagnosed epitheliotropic T-cell lymphoma of the forestomachs in 2 aged, half-sibling, zoo-managed bontebok ( Damaliscus pygargus pygargus). One bontebok also had mesenteric lymph node and cutaneous involvement. Both animals had a history of chronic abdominal distension and diminished body condition that resulted in euthanasia. At autopsy, both animals had marked ruminal distension with diffusely blunted ruminal papillae and reticular crests. In case 1, there was an increased amount and particle length of the ruminoreticular fibrous material with scant fluid, and a 2-cm diameter focus of cutaneous crusting adjacent to a mammary teat. In case 2, the rumen and reticulum were fluid-distended with decreased fibrous material. Histologically in case 1, the rumen, reticulum, omasum, and skin had intraepithelial nests and sheets of neoplastic small lymphocytes; in case 2, the rumen and reticulum had a similar neoplastic cell population. Immunohistochemically, neoplastic lymphocytes were immunoreactive for CD3 and negative for CD20, confirming the diagnosis of epitheliotropic T-cell lymphoma.