Efficacy and adverse events of continuous l-asparaginase administration for canine large cell lymphoma of presumed gastrointestinal origin.

Objectives To examine the efficacy and adverse events of continuous L-asparaginase administration in dogs with large cell lymphoma of presumed gastrointestinal origin. Methods We retrospectively reviewed medical records of dogs with large cell lymphoma of presumed gastrointestinal origin treated with continuous L-asparaginase administration from 2009 to 2018. We collected information on the signalment, lesion site, complete blood count, serum biochemical profile, diagnostic imaging findings, cytological and histopathological findings, immunophenotype, L-asparaginase administration frequency, treatment response, adverse events, rescue protocol, and patient outcomes. Clinical outcomes were assessed using medical records or by contacting the owner or referring veterinarian. Results Thirty-two dogs with large cell lymphoma of presumed gastrointestinal origin received weekly L-asparaginase administration. The median number of L-asparaginase injections was seven (range: 1-30). Although two of the 32 dogs had gastrointestinal toxicity of grade 3 or higher, none developed a hypersensitivity reaction. The response rate based on ultrasonographic findings was 18/32 (56%) and that based on clinical signs was 30/32 (94%). The median overall progression-free survival was 50 days (range: 2-214 days), and median overall survival was 147 days (range: 2-482 days). Clinical significance Adverse events associated with continuous L-asparaginase administration were rare. Clinical signs at diagnosis improved in most cases. Based on these results, continuous L-asparaginase administration appears to be a reasonable treatment option for dogs with large cell lymphoma of presumed gastrointestinal origin. This article is protected by copyright. All rights reserved.