title: Cutaneous metastasis of primary appendicular osteosarcoma in a dog.
abstract: A 6-year-old, neutered male Rottweiler was presented to the University of Illinois Veterinary Teaching Hospital because of a lytic bone lesion involving the distal portion of the right radius and possible pulmonary metastases on thoracic radiographs. Results of serum biochemical analysis were unremarkable. Aspiration and cytologic examination of the bone lesion indicated likely sarcoma with reactive bone. Cutaneous masses were found on the left thigh, interscapular region, and dorsal lumbar region, 4 weeks after initial presentation. Neoplastic spindle cells were found in aspirates from 2 of the masses. The neoplastic cells stained positive for alkaline phosphatase activity using cytochemistry. Re-evaluation of serum biochemical values at this time revealed a marked increase in alkaline phosphatase activity (413 U/L, reference interval 12-110 U/L) compared with the initial value (26 U/L). Due to progressive disease, the dog was euthanized and a necropsy was performed. Histologic findings included primary osteosarcoma of the distal portion of the right radius, with metastases in the lungs, spleen, left fourth and fifth ribs, soft tissue of the right medial thigh, and T1-T3/interscapular region. Cutaneous metastasis of primary appendicular osteosarcoma has been reported rarely in animals and humans. Increased serum alkaline phosphatase activity may be a potential indicator of poor prognosis for this neoplasm.
authors.affiliation: Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA. megorman@uiuc.edu
authors.forename: Elena
authors.initials: E
authors.lastname: Gorman
authors.forename: Anne M
authors.initials: AM
authors.lastname: Barger
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Wypij
authors.forename: Marie E
authors.initials: ME
authors.lastname: Pinkerton
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001859:Bone Neoplasms / Q000201:enzymology / Q000473:pathology / Q000662:veterinary*; D004283:Dog Diseases / Q000201:enzymology / Q000473:pathology*; D004285:Dogs; D017809:Fatal Outcome; D008175:Lung Neoplasms / Q000556:secondary / Q000662:veterinary; D008297:Male; D009362:Neoplasm Metastasis / Q000473:pathology; D012516:Osteosarcoma / Q000201:enzymology / Q000473:pathology / Q000662:veterinary*; D013160:Splenic Neoplasms / Q000556:secondary / Q000662:veterinary
chemical_list: D000469:Alkaline Phosphatase