Bone: Chondroma

2003-05-01   Roberta Vanni 

1.Dip. Scienze e Tecnologie Biomediche, Sezione di Biologia e Genetica, Università di Cagliari, Cittadella Universitaria, 09142 Monserrato (CA), Italy

Summary

Note

Chondroma is an uncommon benign tumour which characteristically forms mature cartilage. It is found mostly in the small bones of the hand and/or feet, although it can also occur in long, tubular bones, primarily the humerus, femur and ribs. Occasionally, focal areas of mixoid degeneration may result in a mistaken diagnosis of chondrosarcoma.

Classification

Classification

Chondromas are classified according to their location:
  • enchondroma: within the bone (within the medullary cavity),
  • periosteal chondroma: on the surface of the bone,
  • soft tissue chondroma in the soft tissue.
  • Clinics and Pathology

    Note

    Fig: Enchondroma in the distal portion of the femur shaft. (courtesy of Dr Henry DeGroot at http://www.drdegroot.com)

  • a) Fig: Ankle periosteal chondroma; {courtesy of Dr Nick Ordall http://www.xray2000.f9.co.uk/)
  • b) Fig: Chondroma of the right femur (courtesy of Dr Henry DeGroot at http://www.drdegroot.com/)
    Periosteal chondroma is a painful cartilaginous lesion that arises from surface of cortex deep to the periosteum, producing broad based cartilaginous mass that may extend into soft tissues; often develops after adolescence. It does not infiltrate the adjacent soft tissue but may increase in size. It is similar in appearance and location to periosteal osteosarcoma. The potential for confusion with periosteal and parosteal osteosarcoma mandates a thorough investigation and biopsy of this lesion. The most common location is adjacent to the metaphysis. The cortex may be involved to a variable degree, but the lesions do not involve the medullary space.
  • Pathology

    Microscopically, enchondroma is hypocellular with few double-nucleated cells without cytologic atypia, but cellularity may vary. There is no permeation of morrow. The matrix does not show any myxoid change. Calcification and ossification are common. Histologic appearance of enchondroma may recall that of a grade-1 chondrosarcoma. The permeation through the cortex into soft tissue must be identified before a diagnosis of chondrosarcoma is made.
    The chondromas in Ollier disease and Maffucci syndrome may demonstrate a greater degree of cellularity and cytologic atypia, and may be difficult to distinguish from chondrosarcoma.

    Treatment

    No treatment is required for asymptomatic lesions. If fracture occurs it is usually treated with curretage and bone grafting.

    Evolution

    A small percentage of enchondromas will undergo malignant transformation, usually throught a slow process, occurring over decades. It is more common in long bones than short.

    Prognosis

    Prognosis for benign enchondroma is excellent. Solitary lesion in the hand rarely undergoes transformation. It has been suggested that Maffucci¹s syndrome is associated with a very high incidence of malignancy, either in the skeleton or in visceral organs.

    Pathology

    It persists as mass of mature cartilage. Low power microscopy shows well circumscribed lobulated hyaline masses. Cellularity can vary, from hypo- to hyper-cellularity. The cartilage looks more active than enchondroma and the lesion may be confused with chondrosarcoma.
    Fig: Bone tumor images (courtesy of Dr Henry DeGroot at http://www.drdegroot.com)

    Treatment

    Periosteal chondromas are treated with conservative excision.

    Prognosis

    Risk of recurrence after bloc marginal excision is less than 10%.

    Note

    Soft-tissue chondroma is a benign cartilage-forming tumor,usually arising from tenosynovial sheaths or the soft tissue adjacent to tendons in the hands and feet, usually without any connection to the underlying bone. Predominantly sited in the fingers, it is usually solitary, develops in adults, and may causes pain. It is composed entirely of mature hyaline cartilage. Infrequently, the tumor undergoes secondary changes and may exhibit morphologic features that result in diagnostic difficulty.

    Pathology

    Microscopically, soft-tissue chondromas vary considerably in appearence. Most consist of hyaline cartilage arranged in lobular pattern, and may show focal fibrosis, ossification, or myxoid change. Diffuse calcification may occur, completely obscuring the cartilagineous nature of the lesion. In some variants, the cartilage matrix becomes extensively mineralized, often associated with necrosis of chondrocytes, causing the tumor to resemble tumoral calcinosis. Hyaline cartilage may also undergo enchondral ossification, mimicking an osteogenic neoplasm or a reactive lesion. Myxoid degeneration may create confusion with extraskeletal myxoid chondrosarcoma.

    Treatment

    Local surgery is the treatment of choice.

    Genetics

    Note

    Cytogenetic studies of chondromas are scarse. A total of 16 cases with abnormal karyotypes have been reported: 6 enchondromas, 4 periosteal chondromas, and 6 soft part chondromas. No consistent abnormality has been detected, although chromosome or chromosomal region 4, 5, 6, 7 and 12q13-15 seems to be nonrandomly involved in changes.

    Bibliography

    Pubmed IDLast YearTitleAuthors
    84025631993Biologic and clinical significance of cytogenetic and molecular cytogenetic abnormalities in benign and malignant cartilaginous lesions.Bridge JA et al
    14585121992Clonal karyotypic aberrations in enchondromas.Bridge JA et al
    126061372003Cytogenetic findings in benign cartilaginous neoplasms.Buddingh EP et al
    90783051997Involvement of chromosomes 6 and 11 in a soft tissue chondroma.Dal Cin P et al
    96668121998Solitary enchondroma with clonal chromosomal abnormalities.Gunawan B et al
    76808881993Rearrangement of band q13 on both chromosomes 12 in a periosteal chondroma.Mandahl N et al
    116680062001Maffucci's syndrome: clinical and radiological features of a rare condition.McDermott AL et al
    127421532003Updates on the cytogenetics and molecular genetics of bone and soft tissue tumors: chondrosarcoma and other cartilaginous neoplasms.Sandberg AA et al
    107482952000Supernumerary ring chromosomes derived from the long arm of chromosome 12 as the primary cytogenetic anomaly in a rare soft tissue chondroma.Shadan FF et al
    117933712002Correlation between clinicopathological features and karyotype in 100 cartilaginous and chordoid tumours. A report from the Chromosomes and Morphology (CHAMP) Collaborative Study Group.Tallini G et al

    Citation

    Roberta Vanni

    Bone: Chondroma

    Atlas Genet Cytogenet Oncol Haematol. 2003-05-01

    Online version: http://atlasgeneticsoncology.org/solid-tumor/5147/bone-chondroma