Chondroblastoma of the temporal bone: a clinicopathologic study of five cases. (1/41)

Chondroblastoma is a rare benign bone tumor. It commonly affects the epiphysis of long bones during the second and third decades of life. Chondroblastoma of the temporal bone is extremely rare. We reviewed five cases of chondroblastoma arising in the temporal bone. Four cases were female and one was male. The ages ranged from 41 to 60 years (mean, 53.6 years). All cases involved the temporal bone. Three involved the left side and two the right. Chief complaints were long-standing localized pain and hearing difficulty. A sharply demarcated lobulated mass was the main radiological finding. Microscopic findings were those of chondroblastoma of usual locations. Two cases showed aneurysmal bone cyst-like areas. Immunohistochemical studies for CD34, CD99, S-100 protein and cytokeratin were performed. Tumor cells were diffusely positive for S-100 protein in three cases and weakly positive for cytokeratin in one case. CD34 and CD99 were negative in all cases. In summary, chondroblastoma of the temporal bone is rare and occurs in older age group than reported cases of chondroblastoma of the usual location in the literature.  (+info)

Extendible replacements of the proximal tibia for bone tumours. (2/41)

Limb salvage is now customary in the treatment of primary bone tumours. The proximal tibia is a frequent site for these neoplasms but reconstruction, especially in children, is a formidable challenge. We reviewed 20 children with extendible replacements of the proximal tibia, all with a minimum follow-up of five years. Five died from their disease and, of the remaining 15, four had above-knee amputations for complications. Infection occurred in seven patients; in five it was related to the lengthening procedure. Aseptic loosening is inevitable in the younger children and only two have avoided a revision, amputation or other major complication; both were aged 12 years at the time of the initial surgery. Despite this, 11 children are alive with a functioning leg and a mean Musculoskeletal Tumour Society functional score of 83%. The lengthening mechanisms used in our series required extensive open operations. We are now using a simpler, minimally invasive, technique which we hope will decrease the incidence of complications. At present, the use of extendible prostheses of the proximal tibia remains an experimental procedure.  (+info)

h-Caldesmon as a specific marker for smooth muscle tumors. Comparison with other smooth muscle markers in bone tumors. (3/41)

Caldesmon is a protein widely distributed in smooth and non-smooth muscle cells and is thought to regulate cellular contraction. Its isoform, high-molecular-weight caldesmon (h-CD), was demonstrated to be specific for smooth muscle cells and smooth muscle tumors of the soft tissue and to never be expressed in myofibroblasts. We performed an immunohistochemical study to examine h-CD expression in the following bone tumors: conventional and non-conventional osteosarcoma, 13; malignant fibrous histiocytoma of bone, 5; giant cell tumors of bone, 5; chondroblastoma, 3; metastatic leiomyosarcoma, 2; and rhabdomyosarcoma, 1. Frequent immunoreactivity for muscle actin (alpha-smooth muscle actin or muscle-specific actin) was seen in 11 of 13 osteosarcomas and all other tumors, whereas h-CD was expressed intensely only in 2 leiomyosarcomas. h-CD is considered a specific and useful marker to distinguish smooth muscle tumor from bone tumors with myoid differentiation.  (+info)

Benign chondroblastoma of bone. Report of a case. (4/41)

A benign chondroblastoma of bone is reported. It was unusual because it occurred in an old lady, in a toe, and it was not painful and radiologically resembled a chondroma. The coarsely lobulated tumour showed a varied microscopic appearance, but it consisted chiefly of closely packed sheets of small, round polygonal or fusiform cells. There was some calcification present. The literature is reviewed.  (+info)

Chondroblastoma of a metacarpal bone mimicking an aneurysmal bone cyst: a case report and a review of the literature. (5/41)

Chondroblastoma of the metacarpal bone has been extremely rare and only seven cases have been reported in the English literature. Here we reported the eighth case of a chondroblastoma that developed on the first metacarpal bone of the right hand of a 21-year-old man. Radiographs showed an expansile osteolytic lesion with a multilocular appearance. In MR images, the lesion showed low intensity in T1 and high intensity in T2-weighted images with multiple fluid-fluid levels, which are findings resembling those of an aneurysmal bone cyst. From the pathological findings, however, it was recognized as a chondroblastoma with aneurysmal bone cyst-like change. Good clinical results was obtained by the subtotal resection of the metacarpal bone with a columnar-shaped iliac bone graft.  (+info)

Coexisting chondroblastoma and osteochondroma: a case report. (6/41)

The coexistence of two different types of benign cartilaginous tumours of bone in the same patient has not been reported in literature. We report a case in which a sixteen-year-old male had a benign chondroblastoma of the proximal left humerus and an osteochondroma of the distal left femur. Both originated at the same time and had a progressive increase in size with growth.  (+info)

Chondroblastoma of the temporal base with high mitotic activity. (7/41)

A 24-year-old man presented with a rare chondroblastoma of the temporal base manifesting as local pain accompanied by difficulty in opening the mouth. Gross total removal was achieved at initial surgery, but the tumor demonstrated rapid and destructive regrowth from a very small residual volume without definite histological malignant transformation. Growth activity estimated by MIB-1 staining increased spontaneously from 2.5% at the initial operation to 18.7% at recurrence. Further extensive radical tumor removal by surgeons from multiple disciplines was performed. The patient has been free of recurrence for 3 years without radiotherapy. Chondroblastoma of the temporal bone is widely accepted as a benign tumor and regrowth after gross total removal is very rare. However, some cases of chondroblastoma have potentially high mitotic activity.  (+info)

Skull base chondroblastoma: a case report. (8/41)

Chondroblastoma is a rare tumor of the skull. Temporal bone is the commonest site of involvement in the skull. We present a thirty one year old man who presented with painless swelling over the left temporal bone, which was near totally excised after preoperative embolization. Management of this unusual tumor and its complications are discussed.  (+info)