Osteosarcoma metastatic to the kidney and iatrogenic hemorrhage.

A 16-year old female presented painful masses in the lumbar region 5 years after the initial diagnosis of a localized osteosarcoma of the tibia. Abdominal X-ray revealed calcified masses. A bone scan confirmed an increased uptake in the renal areas. An ultrasound-guided fine needle biopsy confirmed the diagnosis of metastases. The procedure was complicated by subcapsular hemorrhage and gross hematuria. Renal metastases from osteosarcoma are usually asymptomatic and invisible on abdominal X-rays. The diagnosis is generally established by radionuclide bone scan or abdominal CT-scan. Our observation suggests that histological documentation of these unusual clinical presentations should be carefully weighed against the risk of the procedure. (c) 2007 Wiley-Liss, Inc.