Bone
Cartilaginous tumors other than chondrosarcoma
Chondroblastoma

Author: Nat Pernick, M.D. (see Authors page)

Revised: 29 November 2016, last major update August 2013

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

PubMed Search: Chondroblastoma
Cite this page: Chondroblastoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/bonechondroblastoma.html. Accessed December 11th, 2016.
Definition / General
  • Rare (< 1% of primary bone neoplasms), usually teenage males with open growth plate
  • Painful, often causes joint effusions and restricts joint mobility
  • Sites: distal femur, proximal humerus, proximal tibia, pelvis, ribs, feet, scapula; usually epiphysis (open) or apophysis such as iliac crest; may extend into metaphysis; also skull in older patients
  • Course: usually benign, but commonly recurs (often with atypia), rarely invades locally; rarely pulmonary metastases occur after surgical manipulation of primary tumor; patients survive after removal of localized metastases but not if multiple
Radiology Description
  • Extremely well circumscribed tumor of epiphysis with spotty calcifications in patient with open epiphysis
Radiology Images

Images hosted on Pathout server:

Radiograph of tibia

Femur xray - contributed by Dr. Mark R. Wick

Foot talus xray - contributed by Dr. Mark R. Wick

Humerus xray - contributed by Dr. Mark R. Wick

Proximal humerus xray - contributed by Dr. Mark R. Wick

Treatment
  • Excision or curettage with bone grafting
Case Reports
Gross Description
  • Well circumscribed, white - blue - gray, firm
  • Usually 3 - 6 cm
  • Variable calcification, necrosis, cystic areas
Gross Images

Figures 1/2: expansile and lytic lesion of proximal digit and articular surface
3: giant cells
4: chondroid-type matrix with chicken-wire, pericellular calcifications

Micro Description
  • Varies with time - early hypercellularity, followed by necrosis, followed by fibrous or chondroid areas with occasional spindle cells
  • Compact polyhedral chondroblasts with abundant pink cytoplasm and variable pigment, well defined cell borders and hyperlobulated nuclei with grooves in mineralized, chicken wire matrix that surrounds chondroblasts
  • Chondroid differentiation almost always present (pink vs. blue matrix)
  • May have marked cellularity, intracytoplasmic glycogen granules, mitotic figures, necrosis, osteoclast - type giant cells
  • 25% - 50% have secondary aneurysmal bone cyst
  • Hyaline cartilage is rarely seen
  • No significant nuclear atypia
Micro Images

Images hosted on Pathout server:

Nuclei vary in size

Neoplastic cells with ovoid to spindled nuclei

Well-formed chondroid matrix

Foot talus - contributed by Dr. Mark R. Wick

"Chicken-wire" appearance


Contributed by Dr. Mark R. Wick



Images hosted on other servers:

Quiz cases


Figures 1/2: expansile and lytic lesion of proximal digit and articular surface
3: giant cells
4: chondroid-type matrix with chicken-wire, pericellular calcifications

Positive Stains
Electron Microscopy Description
  • Resembles tissue culture epiphyseal cartilage cells with prominent fibrous lamina that causes microscopic well defined cell borders
Differential Diagnosis
  • Chondromyxoid fibroma: metaphyseal, myxoid with pseudolobular pattern with pleomorphic stellate cells
  • Giant cell tumor: metaphyseal or epiphyseal in patients with closed epiphysis, clustered giant cells that are larger and more numerous than chondroblastoma, no chondroid differentiation, no chicken wire matrix
Additional References