Doxorubicin chemotherapy for presumptive cardiac hemangiosarcoma in dogs†.

Sixty-four dogs were treated with single-agent doxorubicin (DOX) for presumptive cardiac hemangiosarcoma (cHSA). The objective response rate (CR + PR) was 41%, and the biologic response rate (CR + PR + SD), or clinical benefit, was 68%. The median progression-free survival (PFS) for treated dogs was 66 days. The median survival time (MST) for this group was 116 days and was significantly improved compared to a MST of 12 days for untreated control dogs (P = 0.0001). Biologic response was significantly associated with improved PFS (P < 0.0001) and OS (P < 0.0001). Univariate analysis identified larger tumour size as a variable negatively associated with PFS. The high rate of clinical benefit and improved MST suggest that DOX has activity in canine cHSA.

Response of canine cutaneous epitheliotropic lymphoma to lomustine (CCNU): a retrospective study of 46 cases (1999-2004).

BACKGROUND: Epitheliotropic lymphoma (ELSA) is an uncommon cutaneous canine malignancy of T lymphocytes. A consensus regarding the therapeutic standard of care is lacking, warranting evaluation of chemotherapeutic agents traditionally employed against canine nodal lymphoma in the treatment of ELSA. HYPOTHESIS: The purpose of this retrospective, multi-institutional study was to evaluate the efficacy of 1-(2-chloroethyl)-3-cyclohexyl-l-nitrosourea (CCNU) in the treatment of ELSA. ANIMALS: Forty-six dogs with adequate follow-up and treatment response information. METHODS: All cases were diagnosed histopathologically. Immunohistochemisty (CD3, CD79a) was performed on 42/46 samples. RESULTS: Presenting skin lesions included generalized scales (25/46), plaques or nodules (22/46), mucocutaneous lesions (14/ 46), and corneal involvement (1/46). Lymph node involvement and Sézary syndrome were documented in 7 and 2 dogs, respectively. The median number of CCNU treatments was 4 (range, 1-11), with a median starting dose of 60 mg/m(2) (range, 30-95). Of the 46 dogs, 15 achieved complete remission, 23 achieved partial remission, 5 had stable disease, and 3 had progressive disease, for an overall response rate of 83%. The median number of treatments to achieve a response was 1 (range, 1-6). The overall median duration of response was 94 days (range, 22-282). Sixteen dose reductions were required because of neutropenia (10/46), thrombocytopenia (1/46), anemia (1/46), increased liver enzyme activity (3/46), or unspecified reasons (1/46). CONCLUSIONS AND CLINICAL IMPLICATIONS: Given the high response rate and well tolerated protocol, prospective studies are warranted to investigate the utility of CCNU alone or in multi-agent protocols for the treatment of ELSA.

Progression of a solitary, malignant cutaneous plasma-cell tumour to multiple myeloma in a cat.

An 11-year-old male domestic shorthair cat was examined because of a soft-tissue mass on the left tarsus previously diagnosed as a malignant extramedullary plasmacytoma. Findings of further diagnostic tests carried out to evaluate the patient for multiple myeloma were negative. Five months later, the cat developed clinical evidence of multiple myeloma based on positive Bence Jones proteinuria, monoclonal gammopathy and circulating atypical plasma cells. This case represents an unusual presentation for this disease and documents progression of an extramedullary plasmacytoma to multiple myeloma in the cat.