The combination of lomustine and corticosteroids is a valid chemotherapeutic option in cats with presumptive central nervous system lymphoma

Objective
To describe the clinical outcomes of 10 cats diagnosed with CNS lymphoma treated with lomustine and corticosteroids.
Animals
Clinical records of privately owned cats diagnosed with CNS lymphoma and presented to a neurological veterinary
center were reviewed. Inclusion criteria were MRI, CSF analysis, treatment with corticosteroids and lomustine, and
availability of detailed follow-up data. Cats with incomplete data, alternative diagnoses, or concomitant intracranial
conditions as well as those improving after corticosteroid treatment before the diagnosis were excluded. Ten cats
met the inclusion criteria.
Clinical Presentation
The median duration of clinical signs was 7 days. All patients presented with locomotor deficits; 90% exhibited
ataxia. Paresis was observed in 60%, and spinal pain on palpation was also described in 60% of the cats. Cranial nerve
abnormalities were identified in 30% and epileptic seizures were reported in 20% of the cats.
Results
MRI revealed intracranial lymphoma in 40% and spinal lymphoma in 60% of the cases and contrast-enhancing lesions
with meningeal involvement in most of the cases. One cat had elevated CSF cell counts; the others showed normal
cell counts but atypical lymphocytes. Seven cats (70%) were still alive at the 3-month follow-up, with 3 (30%) main-
taining improvement at 6 and 12 months. The treatment did not result in any significant adverse effect.
Clinical Relevance
The combination of lomustine and corticosteroids is a valid chemotherapeutic option in cats with CNS lymphoma. Larger
prospective studies are warranted to compare efficacy of this treatment with that of other chemotherapeutic protocols.