Combination chemotherapy with L-asparaginase, lomustine, and prednisone for relapsed or refractory canine lymphoma

J Vet Intern Med. Jan-Feb 2007;21(1):127-32. doi: 10.1892/0891-6640(2007)21[127:ccwlla];2.


Background: Canine lymphoma (LSA) is responsive to initial treatment, however, it then becomes resistant to drugs in the initial protocol. New rescue protocols are needed.

Hypothesis: A combination of L-asparaginase, lomustine, and prednisone will be well tolerated and efficacious as a rescue therapy for dogs with LSA.

Animals: Thirty-one client owned dogs with cytologically confirmed multicentric LSA who were refractory or whose disease had relapsed after a CHOP (cyclophosphamide/doxorubicin/vincristine/prednisone)-based chemotherapy protocol.

Methods: Prospective clinical trial. Lomustine (target dose, 70 mg/m2) was administered orally at 3-week intervals for a total of 5 doses or until disease progression. L-asparaginase (400 U/kg) was administered subcutaneously concurrently with the first 2 lomustine treatments. Prednisone was administered at a tapering dose for the duration of the protocol.

Results: Overall response rate for dogs treated with this protocol was 87% (27/31), with 52% (16/31) of dogs achieving a complete response. Median time to response was 21 days. Median time to progression was 63 days (111 days for dogs achieving a complete response and 42 days for dogs achieving a partial response). There were no significant differences in response rates and times to progression between dogs who had received L-asparaginase before beginning this rescue protocol and those who had not. Toxicoses were mild and self-limiting in 29 of 31 cases.

Conclusions and clinical importance: This is a well-tolerated rescue therapy for relapsing LSA in dogs. Response rates and remission durations compare favorably to other rescue protocols. Therefore, this protocol is a viable rescue option.

Publication types

  • Clinical Trial
  • Multicenter Study

MeSH terms

  • Animals
  • Antineoplastic Combined Chemotherapy Protocols*
  • Asparaginase / therapeutic use*
  • Dog Diseases / drug therapy*
  • Dogs
  • Drug Resistance, Neoplasm
  • Female
  • Lomustine / therapeutic use*
  • Lymphoma / drug therapy
  • Lymphoma / veterinary*
  • Male
  • Prednisone / therapeutic use*
  • Recurrence
  • Time Factors


  • Lomustine
  • Asparaginase
  • Prednisone