title: A spindle cell tumor of unknown origin and diffuse bone marrow involvement in a patient with hypercalcemia.
abstract: BACKGROUND
  Metastasis of unknown origin in bone marrow is infrequent, although, when it occurs, adenocarcinoma is the most common histologic type. Involvement of bone marrow by a spindle cell tumor and presentation with hypercalcemia are very rare.
  
  
  METHODS
  This report describes a 21-year-old man with diffuse bone marrow involvement from a spindle cell tumor.
  
  
  RESULTS
  The patient presented with low back pain, anemia, thrombocytopenia, azotemia, and hypercalcemia. Bone marrow biopsy revealed a spindle cell tumor that was positive for vimentin staining but whose primary site could not be identified. A bone marrow scan revealed absence of uptake, which suggested systemic disease. We treated this case as a type of sarcoma by giving combined chemotherapy consisting of vincristine, actinomycin-D and cyclophosphamide. The patient showed a clinical response for seven months, but the disease progressed despite chemotherapy and he died one year after diagnosis.
  
  
  CONCLUSIONS
  We have documented a rare case of spindle cell tumor involving bone marrow without evidence of the tumor's primary site.
authors.affiliation: Department of Internal Medicine and Cancer Research Center, Seoul National University College of Medicine, Korea.
authors.forename: J J
authors.initials: JJ
authors.lastname: Yim
authors.forename: G H
authors.initials: GH
authors.lastname: Kang
authors.forename: D S
authors.initials: DS
authors.lastname: Heo
authors.forename: N K
authors.initials: NK
authors.lastname: Kim
mesh_terms: D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D019046:Bone Marrow Neoplasms / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology / Q000556:secondary*; D002277:Carcinoma / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology / Q000556:secondary*; D003520:Cyclophosphamide / Q000008:administration & dosage; D003609:Dactinomycin / Q000008:administration & dosage; D017809:Fatal Outcome; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology*; D008297:Male; D009382:Neoplasms, Unknown Primary; D011877:Radionuclide Imaging; D013669:Technetium Tc 99m Medronate; D014750:Vincristine / Q000008:administration & dosage
chemical_list: D003609:Dactinomycin; D014750:Vincristine; C023568:technetium Tc 99m (Sn)methylenediphosphonate; D003520:Cyclophosphamide; D013669:Technetium Tc 99m Medronate