Feline large granular lymphocyte lymphoma: An Italian Society of Veterinary Oncology (SIONCOV) retrospective study.

Feline large granular lymphocyte (LGL) lymphoma is an uncommon subtype of lymphoma characterized by a grave prognosis and scarce response to chemotherapy. There are limited reports on clinico-pathological and prognostic factors. One-hundred and 9 cats with newly diagnosed LGL lymphoma that underwent initial staging (including hematology, serum biochemistry, thoracic radiographs and abdominal ultrasound), and followed-up were retrospectively evaluated. LGL lymphoma was localized within the gastrointestinal tract with or without extra-intestinal involvement in 91.7% of the cases, and at extra-gastrointestinal sites in 8.3%. Symptoms were frequent. Anemia (31.2%) and neutrophilia (26.6%) were commonly observed, and 14 (12.8%) cats had neoplastic circulating cells. Frequent biochemistry abnormalities included elevated ALT (39.4%) and hypoalbuminemia (28.4%). Twenty (54.1%) of 37 cats had elevated serum LDH. Treatment varied among cats, and included surgery (11%), chemotherapy (23%), corticosteroids (38.5%) and no treatment (27.5%). Median time to progression (MTTP) was 5 days, and median survival time (MST) 21 days. MST was significantly shorter in the case of substage b, circulating neoplastic cells, lack of chemotherapy administration, and lack of treatment response. A small subset of cats (7.3%) survived more than 6 months, suggesting that a more favorable clinical course can be found among LGL lymphoma patients.

Clinicopathological features and outcome for dogs with mast cell tumors and bone marrow involvement.

BACKGROUND: Mast cell tumors (MCTs) with bone marrow (BM) involvement are poorly documented in dogs and are associated with a poor prognosis. Successful treatment strategies have not been described. HYPOTHESIS: Clinicopathologic findings of affected dogs are not specific. Administration of lomustine or imatinib is beneficial. ANIMALS: Fourteen dogs with MCT and BM involvement. METHODS: Clinical and laboratory evaluations were performed in each dog on admission and during follow-up. All dogs received prednisone. Additionally, 8 dogs received lomustine and 3 dogs received imatinib. Imatinib was administered if tumor-associated tyrosine kinase KIT was aberrant. RESULTS: On admission, 11 dogs had a single cutaneous nodule and 3 dogs had multiple nodules. Involvement of regional lymph nodes, liver, or spleen was observed in each dog. BM infiltration with mast cells (MCs) was observed in all dogs. On CBC, nonregenerative anemia, leukopenia, or thrombocytopenia was common. Four dogs had circulating MCs. Increased alkaline phosphatase or alanine transferase activity was observed in 12 and 10 dogs, respectively. Treatment with lomustine induced partial remission in 1 of 8 dogs. Median survival time was 43 days (range, 14-57). Dogs on imatinib experienced complete remission. Two dogs survived for 117 and 159 days, and the third was alive after 75 days. Dogs treated symptomatically did not improve and were euthanized after 1, 14, and 32 days. CONCLUSIONS AND CLINICAL IMPORTANCE: A combination of clinical and laboratory evaluation helps in identifying dogs with MCT and BM infiltration. Administration of lomustine is not helpful in affected dogs. The beneficial effect of imatinib warrants further investigation.