title: High resolution ultrasound features of prostatic rib metastasis: a prospective feasibility study with implication in the high-risk prostate cancer patient.
abstract: OBJECTIVE
  In a prior study, high resolution ultrasound (US) was shown to be accurate for evaluating rib metastasis detected on bone scan. However, that study did not address the specific US appearance typical of osteoblastic rib metastasis. Our objective was to determine the specific US imaging appearance of osteoblastic prostate carcinoma rib metastasis using osteolytic renal cell carcinoma rib metastasis as a comparison group.
  
  
  METHODS
  The Institutional Review Board approval and informed consent were obtained for this prospective feasibility study. We performed high resolution US of 16 rib metastases in 4 patients with prostate carcinoma metastases and compared them to 8 rib metastases in 3 male patients with renal cell carcinoma. All patients had rib metastases proven by radiographs and computed tomography (CT). High resolution US scanning was performed by a musculoskeletal radiologist using a 12-5 MHz linear-array transducer. Transverse and longitudinal scans were obtained of each rib metastasis.
  
  
  RESULTS
  All 16 prostate carcinoma metastases demonstrated mild cortical irregularity of the superficial surface of the rib without associated soft tissue mass, cortical disruption, or bone destruction. 7 of 8 (88%) renal cell carcinoma rib metastases demonstrated cortical disruption or extensive bone destruction without soft tissue mass. One of 8 (12%) renal cell carcinoma rib metastases demonstrated only minimal superficial cortical irregularity at the site of a healed metastasis.
  
  
  CONCLUSIONS
  Osteoblastic prostate carcinoma rib metastases have a distinctive appearance on US. Our success in visualizing these lesions suggests that US may be a useful tool to characterize isolated rib abnormalities seen on a bone scan in high-risk prostate cancer patients who are being evaluated for curative surgery or radiation treatment.
authors.affiliation: University of Wisconsin School of Medicine and Public Health, Department of Radiology, 600 Highland Avenue CSC E3/311, Madison, WI 53792-3252. Electronic address: klee2@uwhealth.org.
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Lee
authors.affiliation: University of Wisconsin School of Medicine and Public Health, Department of Radiology, 600 Highland Avenue CSC E3/311, Madison, WI 53792-3252.
authors.forename: Arthur A
authors.initials: AA
authors.lastname: De Smet
authors.affiliation: University of Wisconsin Carbone Cancer Center, Division of Hematology/Oncology.
authors.forename: Glenn
authors.initials: G
authors.lastname: Liu
authors.affiliation: University of Wisconsin Carbone Cancer Center, Division of Hematology/Oncology.
authors.forename: Mary Jane
authors.initials: MJ
authors.lastname: Staab
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary*; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D005240:Feasibility Studies; D050723:Fractures, Bone; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D012272:Ribs / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography / Q000379:methods
keywords: Fracture; Musculoskeletal ultrasound; Osteoblastic; Osteolytic; Rib metastasis