Clinical-epidemiological, anatomic-pathological, histochemical and immunohistochemical characterization of renal cystadenocarcinoma-nodular dermatofibrosis syndrome in 11 German Shepherd dogs

Abstract

Eleven cases of renal cystadenoma/cystadenocarcinoma-nodular dermatofibrosis syndrome (RCND) are described in German Shepherd dogs diagnosed from January 1994 to January 2018 at the Veterinary Pathology Laboratory of the “Universidade Federal de Santa Maria” (LPV-UFSM). The study sample was composed of eight male and three female dogs at a ratio of 2.67:1. Age ranged from six to 12 years (mean=8.7 years). The main clinical signs reported in descending order of frequency were multiple cutaneous nodules (nodular dermatofibrosis), dyspnea, anorexia, weight loss, recurrent hematuria, vomiting, and polydipsia. Results demonstrated that it is not always easy to clinically recognize this syndrome, but its peculiar anatomical-pathological characteristics allow safe diagnosis. Histologically, it was possible to detect all phases (cysts, papillary intratubular hyperplasia, and cystadenomas or cystadenocarcinomas) of a possible pathological continuum of the renal lesions. Uterine leiomyomas were observed in only one of the cases. Through histochemical techniques, it was possible to identify the presence of type I collagen in both cutaneous and renal lesions and consider its possible involvement in the pathogenesis of renal cystadenocarcinoma. Immunohistochemistry (IHC) showed partially satisfactory results in the staining of epithelial cells of renal cysts and neoplasms for pan-cytokeratin.

Immunohistochemistry of nodular dermatofibrosis in a German Shepherd – a case report

“…If we take into account the first diagnosis of collagen proliferation recorded in our patient five years previously, the survival time of the dog was longer than in dogs with renal adenocarcinoma. Collagen lesions in the skin, kidneys, and the formation of fibrous nodules in the lungs, myocardium, intestinal wall, and on the epiglottis are typical of dermatofibrosis in dogs (Meuten and Meuten 2017;Thompson et al 2019). Collagen is most often produced by fibroblasts, which are specialized cells with this function.…”

“…Clinical signs vary greatly among dogs depending on age and stage of disease at the time of examination (Moe and Lium 1997;Thompson et al 2019). Lesions generally include numerous cutaneous and subcutaneous nodules, distension of the abdomen, anorexia, fatigue, progressive weight loss, polydipsia, vomiting, and obstipation or diarrhoea (Lium and Moe 1985;Thompson et al 2019).…”

“…Lesions found during necropsy demonstrate firm, well-defined cutaneous and subcutaneous nodules, which may extend throughout the body with predisposition to the limbs, head and back (Suter et al 1983). Lesions in the kidney are bilateral, multiple, and cystic (Meuten and Meuten 2017;Thompson et al 2019). Histologically, skin lesions show dermatofibrosis and cystadenocarcinoma in kidneys (Lium and Moe 1985;Souza and Borges 2018).…”