Objective-To investigate the histologic characteristics of feline osteosarcoma (OS) and compare the histologic data with phenotypically comparable canine OS. The effects of histologic and clinical variables on survival statistics were evaluated. Study Design-Retrospective study. Animals-Cats (n ¼ 62) and dogs (22). Methods-Medical records of 62 cats with OS were reviewed for clinically relevant data. Clinical outcome was obtained by telephone interview. Histologic characteristics of OS were classified using a standardized grading system. Histologic characteristics in 22 feline skeletal OS were compared with 22 canine skeletal OS of identical location and subtype. Prognostic variables for clinical outcome were determined using multivariate analysis. Results-Feline OS was characterized by moderate to abundant cellular pleomorphism, low mitotic index, small to moderate amounts of matrix, high cellularity, and a moderate amount of necrosis. There was no significant difference between histologic variables in feline and canine OS. Histologic grade, surgery, and mitotic index significantly influenced clinical outcome as determined by multivariate analysis. Tumor invasion into vessels was not identified as a significant prognosticator. Conclusion-Feline and canine skeletal OS have similar histologic but different prognostic characteristics. Clinical Relevance-Prognosis for cats with OS is related to histologic grade and mitotic index of the tumor. r

After completing this course, the reader will be able to:1. Describe the effect of the addition of rituximab to standard CHOP chemotherapy on the outcome of patients with primary mediastinal large B-cell lymphoma.2. Explain potential changes in the use of radiotherapy and aggressive chemotherapy in the rituximab era.This article is available for continuing medical education credit at CME.TheOncologist.com. CME CME

Summary The prognostic value of baseline serum free light chain ratio (sFLCR) was investigated in 94 multiple myeloma (MM) patients. sFLCR was calculated as κ/λ or λ/κ, depending on the patients’ dominating monoclonal light chain. Median baseline sFLCR was 3·57 in κ‐MM patients, 45·09 in λ‐MM. ‘High’ sFLCR (≥ the observed median value for κ‐ and λ‐MM respectively) correlated with elevated serum creatinine and lactate dehydrogenase, extensive marrow infiltration and light chain type MM. The 5‐year disease‐specific survival was 82% and 30% in patients with sFLCR lower than and equal or greater than the median, respectively (P = 0·0001). sFLCR was an independent prognostic factor.