Clinical characteristics of doxorubicin-associated alopecia in 28 dogs.

Background: Chemotherapy-induced alopecia (CIA) is common in humans, but there are limited reports describing the clinical features of CIA in dogs.

Objectives: To describe the epidemiological and clinical characteristics of doxorubicin-associated alopecia (DAA) in canine patients at a teaching hospital from 2012 to 2014.

Animals: Signalment, diagnosis, treatment protocols and clinical examination findings were recorded in 150 dogs treated with doxorubicin from 2012 to 2014.

Methods: Medical records were searched retrospectively for the keywords "alopecia" and "hypotrichosis." Dogs were excluded if the causal link of hair loss was unclear.

Results: Doxorubicin-associated alopecia was reported in 28 of 150 dogs (19%). Two parameters were statistically associated with the development of DAA: coat-type and cumulative doxorubicin dose. Dogs with curly or wire-haired coat-type were significantly more likely to develop DAA than dogs with straight-haired coat-type [χ (1, N = 147) = 30, P < 0.0001]. After adjusting for sex, weight and doxorubicin dose, the odds of dogs with curly or wire-haired coat-type developing DAA were 22 times higher than those with straight-haired coat-type (P < 0.0001). Dogs that developed DAA received a significantly higher median cumulative doxorubicin dose (103.0 versus 84.5 mg/m ; P = 0.0039) than those that did not develop DAA.

Conclusions And Clinical Importance: Dogs treated with doxorubicin may be at risk for developing DAA. This risk increases as the cumulative dose of doxorubicin increases, and with a curly or wire-haired coat-type.