Introduction

Canine multiple myeloma (MM) is typically treated with melphalan chemotherapy. A protocol with repeated cycles of melphalan dosed “10 days on 10 days off” (10/10) has been used anecdotally at our institution but has not been described in the literature. Our objectives are to use a retrospective case series to describe the outcome and adverse events of the 10/10 protocol and to compare our findings to other protocols reported in the literature. We hypothesize that the 10/10 protocol will have similar outcomes compared to other published protocols.

Methods

Dogs diagnosed with MM that received melphalan treatment at Cornell University Hospital for Animals were identified via a database search. Case records were retrospectively reviewed. Data extracted included signalment, clinical signs prior to diagnosis, staging tests, chemotherapy treatments, response to treatment, duration of treatment, length of follow up, adverse events, and outcome.

Results

Seventeen dogs (4 females, 13 males) met the inclusion criteria. Median age was 10 years old and median body weight was 32 kg. The most common presenting clinical sign was lethargy/weakness. Bone marrow aspiration and analysis occurred in 16/17 dogs. Complete remission was defined by a normalized globulin concentrated and was achieved in 10/17 dogs (59%) with a median time to remission of 39 days. Median progression free survival was 651 days.

Conclusion

Outcome with the 10/10 protocol is similar to that reported for daily melphalan dosing, but lower compared to pulse dosing. Data on prognostic factors and adverse events are still being analyzed for significance and will be presented.

Funding Information

No funding was used for this project.