Dexamethasone, melphalan, actinomycin D, cytosine arabinoside (DMAC) protocol for dogs with relapsed lymphoma.
BACKGROUND
In general, treatment of relapsed lymphoma is associated with a lower probability of response and shorter duration of remission. The purpose of this study was to evaluate the efficacy of the combination chemotherapy protocol DMAC (dexamethasone, melphalan, actinomycin D, and cytosine arabinoside) for reinduction of remission in dogs with relapsed lymphoma.


OBJECTIVE
That DMAC would be an effective reinduction protocol for dogs with relapsed lymphoma.


METHODS
Fifty-four dogs.


RESULTS
Seventy-two percent of the dogs achieved remission (44% complete remission [CR] and 28% partial remission [PR]), 11% had stable disease (SD), and 17% had progressive disease (PD). The median remission duration was 61 days (range, 2-467+ days). The median remission durations for dogs with CR, PR, and SD were 112, 44, and 27 days, respectively. Factors that affected the response rate were previous treatment with doxorubicin and an inability to achieve remission with the previous protocol. Thrombocytopenia occurred in 56% of the dogs (grade 1 in 3 dogs, grade 2 in 6 dogs, grade 3 in 7 dogs, and grade 4 in 7 dogs) and neutropenia in 17% of the dogs (grade 2 in 1 dog, grade 3 in 2 dogs, and grade 4 in 4 dogs). Gastrointestinal toxicosis occurred in 22% of the dogs (grades 1 in 5 dogs, grade 2 in 3 dogs, and grade 3 in 1 dog).


CONCLUSIONS
The DMAC protocol is an effective rescue protocol for dogs with relapsed multicentric lymphoma. Although thrombocytopenia is a common manifestation of toxicity, in general, the protocol is well tolerated.
Alvarez
Francisco J
FJ
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, USA. faberger@yahoo.com
Kisseberth
William C
WC
Gallant
Stacey L
SL
Couto
C Guillermo
CG
D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D003561:Cytarabine / Q000008:administration & dosage / Q000009:adverse effects; D003609:Dactinomycin / Q000008:administration & dosage / Q000009:adverse effects; D003907:Dexamethasone / Q000008:administration & dosage / Q000009:adverse effects; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D005260:Female; D008223:Lymphoma / Q000188:drug therapy* / Q000473:pathology / Q000662:veterinary*; D008297:Male; D008558:Melphalan / Q000008:administration & dosage / Q000009:adverse effects; D009503:Neutropenia / Q000139:chemically induced / Q000662:veterinary; D012074:Remission Induction; D012189:Retrospective Studies; D013921:Thrombocytopenia / Q000139:chemically induced / Q000662:veterinary
D003561:Cytarabine; D003609:Dactinomycin; D003907:Dexamethasone; D008558:Melphalan