An 11-year-old neutered male Golden Retriever presented with lameness of the left forelimb, anorexia, and lethargy. Computed tomography revealed a left humeral mass displaying an aggressive bony lesion with sclerotic changes, raising suspicion of a malignant bone tumor. A hemogram showed marked mature lymphocytosis and moderate nonregenerative anemia. Additional diagnostic methods, including bone marrow aspiration and flow cytometry, definitively diagnosed T-cell chronic lymphocytic leukemia (CLL). Left forelimb amputation was performed, and osteosarcoma was diagnosed based on histopathological examination. Chemotherapy with chlorambucil and prednisolone was initiated for the CLL. Three weeks after treatment, the patient’s clinical signs of anorexia and lethargy resolved, with improvement in lymphocytosis and resolution of anemia. To the best of our knowledge, synchronous osteosarcoma and chronic lymphocytic leukemia have not been reported in veterinary medicine. The concurrent occurrence of osteosarcoma and leukemia has seldom been reported in human medicine, and genetic predisposition is proposed to be a potential risk factor. This is the first documented case report of concurrent osteosarcoma and chronic lymphocytic leukemia detailing its clinical features and diagnostic processes.

Background and Objectives: In patients with perioperative cardiac troponin (cTn) I below the 99th-percentile upper range of limit (URL), mortality according to cTn I level has not been fully evaluated. This study evaluated the association between postoperative cTn I level above the lowest limit of detection but within the 99th-percentile URL and 30-day mortality after noncardiac surgery. Methods: Patients with cTn I values below the 99th-percentile URL during the perioperative period were divided into a no-elevation group with cTn I at the lowest limit of detection (6 ng/L) and a minor elevation group with cTn I elevation below the 99th percentile URL (6 ng/L < cTn I < 40 ng/L). The primary outcome was 30-day mortality. Results: Of the 5,312 study participants, 2,582 (48.6%) were included in the no-elevation group and 2,730 (51.4%) were included in the minor elevation group. After propensity scorematching, the minor elevation group showed significantly increased 30-day mortality (0.5% vs. 2.3%; hazard ratio, 4.30; 95% confidence interval, 2.23–8.29; p<0.001). The estimated cutoff value of cTn I to predict 30-day mortality was 6 ng/L with the area under the receiver operating characteristic curve 0.657. Conclusions A mild elevation of cTn I within the 99th-percentile URL after noncardiac surgery was significantly associated with increased 30-day mortality as compared with the lowest limit of detection.