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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., (© 2020 American College of Veterinary Ophthalmologists.)

Background: Hyperadrenocorticism (HAC), is considered a set of symptoms due to excessive exposure to cortisol. Naturally occurring HAC is most often related to pituitary tumors (pituitary-dependent HAC - PDH). Occult HAC, is referred as a clinical picture highly consistent with HAC; however, routine screening tests are negative. In addition, one or more steroids are elevated following administration of adrenocorticotrophic hormone (ACTH). Ovarian granulosa cell tumors, can produce steroids leading to paraneoplastic syndromes. The objective of this study was to report an unpublished case of ovarian granulosa cell tumor associated with occult hyperadrenocorticism in a Yorkshire Terrier. Case: A 13-year-old intact female dog, Yorkshire Terrier, was brought for consultation with slight weight loss, polyuria, polydipsia, irregular estrous cycles, increased abdominal volume and thin coat. On physical examination the animal was gasping and presented severe periodontal disease, bulging abdomen, alopecia and skin hyperpigmentation. Complete blood count presented no changes; however, serum biochemistry evaluation highlighted hyperalbuminemia, hypertriglyceridemia, alkaline phosphatase increased activity, and urinary specific gravity and creatinine below reference values. On abdominal ultrasonography left adrenal gland measured 2.08 cm x 1.08 cm and the right adrenal gland measured 2.11 cm x 0.84 cm, indicating bilateral adrenomegaly compatible with PDH. In the hypogastric abdomen, a large heterogeneous hypoechogenic mass was also observed, with areas of cystic cavities, measuring 5.80 cm x 7.30 cm. A low dose dexamethasone suppression test (LDDST) was performed, due to PDH suspicion. The test did not confirm HAC, suspecting, then, to be a case of occult/atypical HAC. Due to the strong clinical suspicion, and owner financial problems for further investigated occult HAC, trilostane treatment was initiated. Approximately one month after starting treatment, an ACTH stimulation test (AST) for cortisol and 17-hydroxyprogesterone (17-OHP) determination was performed, revealing high values for both hormones. Exploratory laparotomy was indicated due to the tumor image on hypogastric region visualized on abdominal ultrasonography. A cranial pole mass of the left ovary measuring 8.5 x 7.0 x 4.5 cm, of friable consistency and brownish color, was removed through ovariohysterectomy. A granulosa cell tumor on left ovary, as well as leiomyoma and cystic endometrial hyperplasia in the uterus, became clear through histopathological examination. Trilostane treatment was sustained after surgery. Few weeks later, the patient presented a clinical picture suggestive of hypoadrenocorticism, associated with a low sodium:potassium ratio (25:1), and AST results (basal and post-ACTH cortisol) below reference range, confirming Addisonian' crises. The patient deceives within two days. Discussion: Granulosa cell tumors can produce estrogen and progesterone, as well as other steroids, leading to paraneoplastic syndromes with peculiar clinical presentations. Steroids transport in plasma occurs via specific carrier proteins. Increased production of other steroid hormones may result in higher concentration of free cortisol, thus leading to clinical manifestations of hypercortisolism. As 17-OHP is one of the precursors in cortisol synthesis and has been shown elevated on AST, it can be assumed that altered steroid hormone levels due to the granulosa cell tumor interfered on cortisol biodisponibility, leading to HAC signs. Dexamethasone suppression test results indicated that pituitary-adrenal axis was responsive to negative feedback. The Addisonian crises after tumor removal indicate that the main source for systemic excessive cortisol effects was the eminent steroid secretion by the granulosa cell tumor. [ABSTRACT FROM AUTHOR]

A carcinoid is a rare neoplasm derived from neuroendocrine cells that may arise in the hepatobiliary system. This report described two cases of carcinoid of the gallbladder in dogs, with emphasis on the clinical, pathological and immunohistochemical aspects. Case 1 was a 10-year-old female Shih Tzu, with a history of prostration and occasional episodes of diarrhea and vomiting. Case 2 was a 10-year-old male Cocker Spaniel, with a history of diarrhea and abdominal pain. Abdominal ultrasonography suggested a neoplasm of the gallbladder in both cases. The dogs underwent cholecystectomy, and 10% formalin-fixed samples were sent for pathological examination. Histologically, a neoplastic proliferation of neuroendocrine cells was observed in the gallbladder submucosa of both cases. Immunohistochemical labeling for neuroendocrine antibodies, such as synaptophysin, neuron-specific enolase and chromogranin A, confirmed the diagnoses. Carcinoid of the gallbladder is a rare neoplasm in dogs, without specific clinical signs, but should be included in the differential diagnosis of lesions that affect this organ. [ABSTRACT FROM AUTHOR]

Scirrhous eosinophilic gastritis (SEG) is characterized by diffuse infiltration of eosinophils and concomitant fibrovascular tissue proliferation in the stomach wall. The condition is a rare occurrence with an unknown cause. Two dogs were examined with a history of progressive weight loss, emesis, melena and anorexia. Complete blood cell counts of both cases revealed anemia and eosinophilia, while ultrasonography examination revealed thickening of the stomach wall. Due to suspected gastric neoplasia and a poor clinical prognosis, the dogs were euthanized. At necropsy, both had markedly distended stomachs with a diffusely thickened and firm wall. The spleens of both dogs were enlarged with a nodular surface. Histological evaluation revealed diffuse infiltrate of eosinophils, fibrovascular tissue proliferation and fibrinoid degeneration in blood vessel walls of stomach and spleen. SEG is a rare pathological condition that must be considered as a possible diagnosis in dogs presenting gastrointestinal signs and eosinophilia. [ABSTRACT FROM AUTHOR]