CCNU for the Treatment of Dogs with Histiocytic Sarcoma

Abstract

Results suggest that CCNU is active against canine histiocytic sarcoma and may be useful in the treatment of dogs without negative prognostic factors.

A Retrospective Study of Multi‐agent Chemotherapy including either Cyclophosphamide or Lomustine as Initial Therapy for Canine High‐grade T‐cell Lymphoma (2011‐2017)

“…One patient presented at day 5 post‐lomustine with febrile grade 4 neutropenia, highlighting that the neutrophil nadir in dogs can be variable and treating veterinarians must warn owners to monitor pets carefully in the first week after lomustine administration. Neutropenia is typically the dose‐limiting toxicity for lomustine and high incidences of neutropenia are well‐reported . This study exemplifies that careful monitoring for high grade haematological toxicities is required when using the drug lomustine in clinical cases and supports the recommendation to perform a haematology 7 days after the first treatment.…”

Clinical prognostic factors in canine histiocytic sarcoma

“…Histiocytic sarcoma (HS) may present as a localized tumour or disseminated disease, but eventually widespread metastasis occurs with a frequently fatal outcome. Three forms of the disease have been recognized based on the cellular origin of the tumour and the clinical manifestation of the disease: disseminated HS (DHS), localized HS (LHS) and hemophagocytic HS (HHS) . The HHS is immunophenotypically distinct and carries a grave prognosis .…”

“…The HHS is immunophenotypically distinct and carries a grave prognosis . Both localized and disseminated cases of canine HS arise from interstitial dendritic antigen presenting cells (DAPCs), but exhibit variable clinical behaviour . Localized and disseminated forms of HS present with identical histopathological features and manifest as poorly demarcated masses composed of pleomorphic, large, individualized round cells, or densely packed bundles of plump spindle cells .…”

“…Despite reported metastatic rates of 70–91%, treatment for dogs with HS consisting of surgery, radiation, chemotherapy or a combination, appears to improve survival outcome . In a study of 59 dogs with DHS, 54% of dogs that lived longer than 7 days following the first treatment with CCNU responded to therapy, and responders had a median survival time of 5.5 months . LHS manifests as a primary tumour that most commonly develops in the skin and subcutis, although it may also be found in periarticular tissues surrounding large appendicular joints, or in the spleen, lymph nodes, lung or bone marrow .…”

“…In a study of 59 dogs with DHS, 54% of dogs that lived longer than 7 days following the first treatment with CCNU responded to therapy, and responders had a median survival time of 5.5 months . LHS manifests as a primary tumour that most commonly develops in the skin and subcutis, although it may also be found in periarticular tissues surrounding large appendicular joints, or in the spleen, lymph nodes, lung or bone marrow . Dogs diagnosed with LHS appear to have a better prognosis when treated compared to dogs diagnosed with DHS, having median survival times of up to 18.9 months …”