Routine chest radiograph of an asymptomatic 50- year-old man. The same study five years earlier had shown no abnormality.
The radiograph shows a solitary “white” fourth rib on the left side. Such a finding in a middle-aged or older man should always suggest osteoblastic metastasis, particularly from carcinoma of the prostate. In this patient, biopsies of the prostate and affected rib disclosed adenocarcinoma.