A comparison of clinical, magnetic resonance imaging and pathological findings in dogs with gliomatosis cerebri, focusing on cases with minimal magnetic resonance imaging changes^‡

Abstract

The primary study objective was to determine whether clinical examination and magnetic resonance imaging (MRI) can underestimate canine gliomatosis cerebri (GC); we also investigated immunohistochemical features. Seven dogs with GC were studied; four recruited specifically because of minimal MRI changes. Neuroanatomic localization and the distribution of MRI, gross and sub-gross lesions were compared with the actual histological distribution of neoplastic cells. In six cases, clinical examination predicted focal disease and MRI demonstrated a single lesion or appeared normal. Neoplastic cells infiltrated many regions deemed normal by clinical examination and MRI, and were Olig2-positive and glial fibrillary acid protein-negative. Four dogs had concurrent gliomas. GC is a differential diagnosis for dogs with focal neurological deficits and a normal MRI or a focal MRI lesion. Canine GC is probably mainly oligodendrocytic. Type II GC, a solid glioma accompanying diffuse central nervous system neoplastic infiltration, occurs in dogs as in people.

Magnetic resonance imaging features of canine gliomatosis cerebri

“…In comparison to dogs with other brain tumors, the mean age of 14 dogs included in the present study was lower (mean 6 years) compared to dogs with other types of brain tumor (mean and median reported around 9 years) . However, the ages of our cohort are comparable to those of cases of canine gliomatosis cerebri reported in the literature . In humans, gliomatosis cerebri may affect all age groups, but a peak incidence is reported in the second and fifth decades of life, and particularly this first peak might correspond to dogs less than 6 years of age .…”

“…11,12 In dogs with gliomatosis cerebri, variable MRI findings have been reported, ranging from no morphological changes to the presence of diffuse and solid mass lesions. 1,[13][14][15][16][17][18] Although the most recent publication focused on cases without or only minimal signal changes on MRI, 18 we observed in our clinical cases severe changes with a widespread growth pattern. The purpose of this retrospective study was to describe MRI characteristics of gliomatosis cerebri in a series of dogs with histopathological confirmation.…”

“…On MRI of humans, affected brain parenchyma usually shows hyperintense signals on T2‐weighted and FLAIR images . In dogs with gliomatosis cerebri, variable MRI findings have been reported, ranging from no morphological changes to the presence of diffuse and solid mass lesions . Although the most recent publication focused on cases without or only minimal signal changes on MRI, we observed in our clinical cases severe changes with a widespread growth pattern.…”

“…5,8 In veterinary medicine, the term gliomatosis cerebri has been used more broadly, even in cases with diffuse glial cell infiltration involving only the spinal cord or brain stem and exhibiting a lack of forebrain lesions. 17,18,22 In all dogs examined in this study population, MRI clearly showed that the lesions extended through at least three contiguous cerebral lobes, with involvement of white and gray matter. Furthermore, we frequently observed concurrent changes within the forebrain and the caudal cranial fossa.…”

Serological prevalence of toxoplasmosis and neosporosis in dogs diagnosed with suspected meningoencephalitis in the UK

“…). Differential diagnoses for multi‐focal intracranial lesions would include inflammatory meningoencephalitis, neoplasia (lymphoma, gliomatosis cerebri, metastatic disease), metabolic, degenerative and cerebrovascular disorders (Cherubini et al ., , Wolff et al ., ; Bentley et al ., ). A normal MRI examination does not rule out CNS inflammatory disease (Lamb et al .…”