Page 1308 - Clinical Small Animal Internal Medicine

1246 Section 11 Oncologic Disease

excellent prognosis. In some cases, RT has been used for for survival. Fernandez showed that renal disease and a
VetBooks.ir nonresectable or recurrent EMPs as well as melphalan high blood neutrophil to lymphocyte ratio around the
time of diagnosis also negatively impacts survival. Ionized
and prednisone alone, or combined with RT. In cases
with SOP, surgical excision when possible or RT is the
evaluated were not prognostic.
treatment of choice. Fracture repair, or spinal cord hypercalcemia and osteolytic lesions among other factors
decompression and vertebral stabilization, followed by In cats, data are based on small numbers. Overall
RT could be considered when appropriate. Chemotherapy remission rate is lower and survival times shorter com­
may be used when RT is not available. Both modalities pared to dogs. A MST of 9.5 months was reported in one
have resulted in prolonged local control that is not nec­ study and no cat lived more than six months in another.
essarily accompanied with bone remodeling. The prognosis for solitary cutaneous and mucocuta­
neous EMPs in dogs is generally good. Surgical excision
is curative in most cases. Local recurrence rate is
Prognosis reported to be approximately 5% (higher for oral tumors),
nodal or systemic disease develops in 2% and new cuta­
Two larger case series of dogs with MM, treated with neous EMPs occur in less than 2% of dogs. Cell type, pro­
melphalan and prednisone, have been published to date, liferation rate, presence of amyloid, and cyclin D1
32 years apart. One compared continuous and pulse pro­ reactivity have no prognostic significance in dogs. Dogs
tocols and found no statistically significant difference in with multiple cutaneous EMPs in the absence of MM
any of the outcome variables, although a small cohort size have been assigned a diagnosis of cutaneous plasmacyto­
and high numbers of censored dogs could have impacted sis (CP) based on the rare syndrome in humans, that usu­
the results. In both studies, some dogs received an initial ally follows an indolent course. In the first reported
dose of cyclophosphamide as well. In the first study series, 21 dogs with CP were treated with chemotherapy,
(Matus et al), a complete response (undetectable serum most with melphalan and prednisone. The overall
monoclonal Ig) was observed in 43% of dogs, partial response rate was 74%, complete response was 37%,
response (≥ 50% decrease in Ig) in 49% and no response in median progression free survival was 143 days, but
only 8%. The median survival time (MST) of all 37 dogs median overall survival was longer at 542 days. None of
was 540 days and the addition of cyclophosphamide did the dogs progressed to develop MM. In cats, EMP behav­
not affect survival. In the second study (Fernandez et al), ior is less predictable. Some remain localized and surgi­
overall response rate was similar (86%), but most were cal excision can lead to long‐term control while others
defined as having a complete response. Median survival progress rapidly to MM.
time for all 38 dogs was 930 days, almost double the time As in humans, veterinary patients with successfully
in the first study. Additionally, twelve dogs in the first treated SOP eventually develop local failure, new lesions
study were treated with prednisone alone and their MST or MM but they can enjoy long disease‐free periods until
was 220 days. Matus reported that a response to treat­ progression. It is important to thoroughly stage them at
ment with chemotherapy was positively associated with initial diagnosis and to monitor routinely for local and
survival. Hypercalcemia, Bence Jones proteinuria and systemic relapse with serum globulin levels, careful atten­
extensive bone lesions were negative prognostic indicators tion to bone pain, and additional diagnostics if indicated.

Further Reading

Fernandez R, Chon E. Comparison of two melphalan neoplasms in contrast to myeloma in human patients: 24
protocols and evaluation ofoutcome and prognostic cases with clinical follow‐up. J Vet Intern Med 2006;
factors in multiple myeloma in dogs. J Vet Inern Med 20(6): 1376–83.
2018; 32: 1060–1069. Patel RT, Caceres A, French AF, et al. Multiple myeloma in
Kupanoff PA, Popovitch CA, Goldschmidt MH. Colorectal 16 cats: a retrospective study. Vet Clin Pathol 2005; 34:
plasmacytomas: a retrospective study of nine dogs. J Am 341–52.
Anim Hosp Assoc 2006; 42: 37–43. Terpos E, Roodman DG, Dimopoulos MA. Optimal use of
Matus RE, Leifer CE, MacEwen GE, et al. Prognostic bisphosphonates in patients with multiple myeloma.
factors for multiple myeloma in the dog. J Am Vet Med Blood 2013; 121: 3325–8.
Assoc 1986; 188(11): 1288–92.
Mellor PJ, Haugland S, Murphy S, et al. Myeloma‐related
disorders in cats commonly present as extramedullary