Malignant transformation of a high-grade osteoblastoma of the petrous apex with subcutaneous metastasis.
We describe the clinical presentation, management, and pathologic findings in a case of osteosarcoma of the petrous apex with an atypical metastasis to the lower abdominal wall. We retrospectively reviewed the record of a 49-year-old man who was diagnosed with a right petrous apex lesion, which biopsy identified as a high-grade osteoblastoma. After two attempts at en bloc resection were not curative, radiation and chemotherapy were recommended. The patient subsequently developed a cutaneous lower abdominal mass that was diagnosed as an osteosarcoma. Meanwhile, the petrous apex tumor continued to grow despite treatment until the patient died from the burden of disease. Temporal bone osteoblastomas and osteosarcomas are both extremely rare, and they can be difficult to differentiate histologically. Our case illustrates this difficulty and demonstrates the possibility of a high-grade osteoblastoma's malignant conversion to an osteosarcoma.
Department of Otolaryngology-Head and Neck Surgery, University of Michigan Health System, 1904 Taubman Center, 1500 E. Medical Center Dr., SPC 5312, Ann Arbor, MI 48109-5312, USA.
Casey T
CT
Kraft
Robert J
RJ
Morrison
H Alexander
HA
Arts
D034861:Abdominal Wall / Q000473:pathology*; D001706:Biopsy; D002471:Cell Transformation, Neoplastic; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018215:Osteoblastoma / Q000000981:diagnostic imaging* / Q000473:pathology; D012516:Osteosarcoma / Q000473:pathology* / Q000556:secondary; D010579:Petrous Bone / Q000000981:diagnostic imaging* / Q000473:pathology; D012888:Skull Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D012983:Soft Tissue Neoplasms / Q000473:pathology* / Q000556:secondary