Purpose: We identified a subset of patients with renal cell carcinoma (RCC) who have a high likelihood of presenting with bone metastasis and would most benefit from a preoperative bone scan.
Materials and methods: A database of 1,357 patients undergoing nephrectomy and/or immunotherapy for RCC at our institution was queried. Patients presenting with metastasis to the bones were identified and stratified according to T stage, Eastern Cooperative Oncology Group (ECOG) score, musculoskeletal symptoms and alkaline phosphatase.
Results: Of the patients 37% presented with metastasis. Bone metastasis was identified in 14% of patients. The incidence of bone metastasis was 5.4%, 13.8%, 15.4% and 28.2% in patients with T1 to T4 lesions, and 1.4%, 19% and 41% in those with an ECOG score of 0 to 2 and greater, respectively. T stage and ECOG score were then integrated. Bone metastasis was confirmed in 0.046%, 3.8%, 1.4% and 0% of patients with T1 to T4/ECOG 0 disease, and in 13.4%, 20%, 21.5% and 31% of those with T1 to T4/ECOG greater than 0 disease, respectively (p < 0.0001). Only 1.4% of patients with an ECOG score of 0 harbored bone metastasis, of whom 71% complained of musculoskeletal pain, 100% manifested extraosseous metastases and 25% had increased alkaline phosphatase at presentation.
Conclusions: Performance status is an important predictor of bone metastasis in patients presenting with presumed RCC lesions. Bone scan should be performed in patients with an ECOG score of greater than 0 regardless of T stage but is unnecessary in those presenting with an ECOG score of 0, particularly when lacking symptoms and extraosseous metastasis.