Clinicopathological characteristics of histiocytic sarcoma affecting the central nervous system in dogs

Abstract

Background Histiocytic sarcoma affecting the central nervous system (CNS HS) in dogs may present as primary or disseminated disease, often characterized by inflammation. Prognosis is poor, and imaging differentiation from other CNS tumors can be problematic. Objective To characterize the clinicopathological inflammatory features, breed predisposition, and survival in dogs with CNS HS. Animals One hundred two dogs with HS, 62 dogs with meningioma. Methods Retrospective case series. Records were reviewed for results of cerebrospinal fluid (CSF) analysis, CBC, treatment, and outcome data. Results Predisposition for CNS HS was seen in Bernese Mountain Dogs, Golden Retrievers, Rottweilers, Corgis, and Shetland Sheepdogs (P ≤ .001). Corgis and Shetland Sheepdogs had predominantly primary tumors; Rottweilers had exclusively disseminated tumors. Marked CSF inflammation was characteristic of primary rather than disseminated HS, and neoplastic cells were detected in CSF of 52% of affected dogs. Increased neutrophil to lymphocyte ratios were seen in all groups relative to controls (P <.008) but not among tumor subtypes. Definitive versus palliative treatment resulted in improved survival times (P < .001), but overall prognosis was poor. Conclusions and Clinical Importance Clinicopathological differences between primary and disseminated HS suggest that tumor biological behavior and origin may be different. Corgis and Shetland Sheepdogs are predisposed to primary CNS HS, characterized by inflammatory CSF. High total nucleated cell count and the presence of neoplastic cells support the use of CSF analysis as a valuable diagnostic test. Prognosis for CNS HS is poor, but further evaluation of inflammatory mechanisms may provide novel therapeutic opportunities.

Clinical features, diagnosis, and survival analysis of dogs with glioma

“…Treatment groups were defined as definitive if specific treatment modalities including surgical resection, radiotherapy, or chemotherapy were used in any combination, and palliative if corticosteroid, antiepileptic, or analgesic medications were the only therapeutic interventions. 33 Survival was defined for all cases from time of MRI diagnosis, and only for cases with survival times >1 day to exclude animals euthanized at the time of diagnosis. 33 …”

“… 33. Survival was defined for all cases from time of MRI diagnosis, and only for cases with survival times >1 day to exclude animals euthanized at the time of diagnosis 33. 2.6 | Statistical analyses…”

Prolonged survival of a 7‐year‐old vizsla with histiocytic sarcoma affecting the spinal cord and protein‐losing nephropathy after lomustine treatment

“…The CNS may be infiltrated by HS as a primary location or as a consequence of metastatic spread of disseminated HS. [1][2][3] Occurrence of the primary HS in the spinal cord is uncommon. [1][2][3] In the study by Toyoda and others, 3 from 108 dogs diagnosed with HS affecting the CNS in 8 dogs, HS was localised to the spinal cord only.…”

“…[1][2][3] Occurrence of the primary HS in the spinal cord is uncommon. [1][2][3] In the study by Toyoda and others, 3 from 108 dogs diagnosed with HS affecting the CNS in 8 dogs, HS was localised to the spinal cord only. Extracranial metastasis of primary CNS HS is considered very unlikely and has not yet been formally reported in the veterinary literature.…”

“…Kidneys are affected mainly in cases of disseminated HS. 4 6 7 Published studies of HS affecting CNS in dogs 2 3 described the survival rate from 1 to 217 3 days. The survival time of 881 days of the dog presented in this case report markedly exceeded this so far reported survival time.…”