Metastatic Tumors to the Adrenal Glands in Domestic Animals

Abstract

Abstract. Although metastases to the adrenals are common in humans, they have not been thoroughly studied in animals. The purpose of this retrospective study was to document the types of malignant tumors that metastasize to canine, feline, equine, and bovine adrenals, and the rate at which they do so. The average rate of adrenal involvement in metastatic cancer was 112/534 (21.0%) in dogs, 12/81 (14.8%) in cats, 18/67 (26.9%) in horses, and 5/16 (31.3%) in cattle. In dogs, 26 different tumor types metastasized to the adrenals. Pulmonary, mammary, prostatic, gastric, and pancreatic carcinomas, and melanoma had the highest rates of metastasis to the adrenal glands in dogs. Hemangiosarcoma and melanoma had high rates of adrenal involvement in horses. In cats and cattle, relevant data were only available for lymphoma. Adrenal metastases usually occurred in the late stages of the disease. One dog had developed Addison's disease (hypoadrenocorticism) secondary to lymphoma. Metastatic lesions represented 126/472 (26.7%) of canine, 12/20 (60.0%) of feline, 21/80 (26.3%) of equine, and 5/9 (55.5%) of bovine adrenal neoplasms. This study shows that adrenal glands should be thoroughly examined during both clinical work-up and postmortems when disseminated neoplasia is suspected.Key words: Adrenal glands; cats; cattle; dogs; endocrine diseases; horses; neoplasm metastasis; neoplasms.Metastatic tumor is the most common neoplastic lesion in the adrenal glands of humans and is especially common with lung, breast, and gastric carcinomas, and melanoma. 1,[13][14][15]24,34,36 They are the fourth most common site of metastasis after lung, liver, and bone. 15 The common occurrence of metastases to the adrenals is thought to be related to the rich sinusoidal blood supply. 13,16 Adrenal metastases only infrequently cause hypoadrenocorticism, possibly because an estimated 90% of the adrenal cortex must be compromised before abnormal gland function is detectable and hyperplasia of the remaining adrenal may compensate for the loss of tissue. 4,13,16 When hypoadrenocorticism does occur, the resulting clinical signs may be overlooked and wrongly attributed to nonspecific effects of widespread neoplastic disease. 13,16,25,30,36 Also, the use of treatment protocols that include steroids may mask symptoms and complicate the diagnosis of hypoadrenocorticism. 25,30,36 In domestic animals, metastases to the adrenal glands have only been occasionally described, mostly as single cases. 2,3,[5][6][7][8]10,[19][20][21][22][23][26][27][28][29][31][32][33]35,[37][38][39] To the authors' knowledge, there are no published reports on the rate of adrenal involvement in metastatic disease for specific tumor types in domestic animals. Hypoadrenocorticism due to tumor spread has been reported in two cats but has not been reported in other animals. 29 In this study, we describe the rate and features of metastatic lesions to the adrenal glands of domestic animals. Materials and MethodsThe records of canine, feline, equine, and bovine patients admitted to the ...

Addisonian Crisis due to Metastatic Adenocarcinoma in a Pygmy Goat

“…Common tumor types that metastasize to the adrenal gland include carcinoma, adenocarcinoma, and lymphoma. Only one dog was reported to have developed Addison's disease secondary to the metastatic neoplasia [12]. Necropsy findings in this doe revealed that the metastatic adenocarcinoma originated from the uterus and infiltrated multiple abdominal organs.…”

“…Histological examination of the adrenal glands after euthanasia revealed highly anaplastic bilateral adrenal neoplasia. According to a recent retrospective study, the average rate of metastatic involvement of the adrenal glands is 21% in dogs, 26.9% in horses, and 31.3% in cattle [12]. No goat necropsies were involved in that study.…”

Lesões de adrenais em 300 cães

“…Tumores primários foram mais prevalentes (75,7% dos casos de neoplasma). As adrenais foram sítios de metástase em nove cães (24,3% dos casos de neoplasma), incidência semelhante ao que é reportado na literatura (Labelle & De Cock 2005).…”

“…Os demais tumores metastáticos foram: osteossarcoma, melanoma, linfoma, colangiocarcinoma, sarcoma histiocítico e adenocarcinoma pulmonar. Foi reportado que em 40,2% dos casos as metástases são encontradas na avaliação macroscópica das adrenais de cães, o restante é detectado apenas durante a avaliação histológica (Labelle & De Cock 2005). Neste estudo, em 77,8% dos cães com metástases, essas só foram visualizadas histologicamente.…”

Primary Hypoadrenocorticism in a Dog

“…Main findings in affected dogs were severe lymphoplasmacytic inflammation and atrophy of all layers of the adrenal cortex (FRANK et al, 2013). Other rare causes included granulomatosis destruction, amyloidosis, hemorrhage, metastatic neoplasm (LABELLE; DE COCK, 2005;RO-CKWELL et al, 2005;REUSCH et al, 2007;FRANK et al, 2013) and the use of drugs as mitotane and trilostane which induce the adrenal glands necrosis (REUSCH et al, 2007).…”