Bone
Hematologic neoplasms
Solitary plasmacytoma

Author: Sheren Younes, M.D. (see Authors page)

Revised: 28 October 2016, last major update April 2014

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

PubMed search: solitary plasmacytoma [title] bone

Cite this page: Solitary plasmacytoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/bonesolitaryplasmacytoma.html. Accessed December 6th, 2016.
Definition / General
  • Defined by WHO 2008 as a localized bone tumor consisting of monoclonal plasma cells, with no other bone lesions, no bone marrow involvement and no clinical features of myelomas
Epidemiology
  • Rare; < 5% of myeloma patients
  • Majority are males
  • Median age is 50 - 55 years
Sites
  • Sites of active bone marrow hematopoiesis
  • 40% - 60% in axial spine; also vertebrae, thoracic more than lumbar and cervical
  • Followed by ribs, skull, pelvis, femur, clavicle, scapula
  • Long bone involvement below elbow and knee are rare
  • Rarely involves lymph nodes or peripheral blood
Clinical Features
  • Incidental finding
  • May have bone pain and pathologic fracture
  • May cause soft tissue mass
Diagnosis
  • Diagnostic criteria:
  • Single bony lesion consisting of monoclonal plasma cells; MRI may be needed to exclude involvement of other sites
  • No bone marrow involvement
  • No clinical features of myeloma, such as anemia, hypercalcemia and renal failure
  • Absence or low levels of M protein in urine
  • Normal levels of uninvolved polyclonal immunoglobulins (Br J Haematol 2004;124:717)
Laboratory
  • CBC, renal function tests, serum calcium (to exclude myeloma)
  • Immunofixation studies in serum and urine (M protein detection)
Radiology Description
  • Osteolytic lesions, similar to myeloma
  • May show soft tissue extension
  • Vertebral involvement may be associated with spinal cord or nerve root compression
Radiology Images
Images hosted on PathOut server:

Pelvis xray, by Dr. Mark R. Wick

Skull xray, by Dr. Mark R. Wick



Images hosted on other servers:

Lobulated osteolytic sternal lesion

Prognostic Factors
  • Median survival is 10 years
  • 50% eventually develop myeloma, 1 / 3 remain disease free > 10 years after radiotherapy
  • Poor prognostic factors are large size and M protein persistence after radiotherapy
Case Reports
Treatment
  • Local control by radiotherapy is curative for most cases
Clinical Images
Images hosted on other servers:

Huge, firm, nonpulsatile anterior chest wall mass

Micro Description
  • Similar to myeloma, easily diagnosed unless plasmablastic or anaplastic
  • Cytologic, immunophenotypic and molecular features are similar to myeloma
Micro Images
Images hosted on PathOut server:

With amyloid and Congo red stain, by Dr. Mark R. Wick



Images hosted on other servers:

Various images

H&E, CD45+, CD10+