Benign extraosseous cartilage tumours of the hand and wrist.

Benign extraosseous cartilage tumours of the hand and wrist comprise soft tissue chondromas, synovial chondromatosis and tenosynovial chrondromatosis. These tumours can significantly affect patients as they are often painful, functionally limiting and cosmetically displeasing. Although each tumour is generally considered to be a distinct entity, they share radiological and histopathological similarities. Occasionally, all three tumours may be seen in the same patient. This is an important consideration because of the risk of recurrence that may not necessarily occur at the same anatomical site but instead extend to different sites, such as a tendon sheath and/or joint.

Bifocal sclerosing osteosarcoma: unusual presentation and course.

Multifocal osteosarcoma is uncommon. Long-term survival of an incompletely treated case is exceptional. We report an unusual case of bifocal sclerosing osteosarcoma in a 38-year-old women that involved the left ilium and right proximal femur. The femoral lesion was resected. The tumor in the left ilium was not treated. She did not receive chemotherapy and has been free of metastases for 7 years. Recently, growth of the pelvic osteosarcoma has resulted in vascular compression and edema of the lower extremity. The patient's alkaline phosphatase has been elevated throughout. The tumor was HMB-45 positive, which has not been previously reported in osteosarcoma. The pathogenesis of multifocal osteosarcoma is discussed.

Myxoid chondrosarcoma of soft tissue and bone: a retrospective study of 11 cases.

This article describes 11 cases of myxoid chondrosarcoma (MCS), with 10 arising in soft tissues and one developing in bone. Most of the tumors (six) were located in the lower extremities. Two lesions developed in the fingers, a previously unreported location for MCS. Four cases showed secondary bone destruction, which is a rare feature of this tumor. S100 protein was expressed by tumor cells in all the specimens. Four out of eight tumors studied by electron microscopy contained intracisternal microtubular structures. Two tumors showed areas of spindle cell proliferation that merged with the areas of typical myxoid pattern. The cells in these areas had fibroblastic/myofibroblastic features by electron microscopy and were found to express cytokeratin by immunohistochemistry. The concomitant expression of cytokeratin and S100 protein in the spindle cells suggests that they represent a less differentiated cartilaginous component with unusual features. The clinical significance of the presence of such spindle cell areas presently remains unknown. Although myxoid chondrosarcoma is a slow-growing tumor, it has a high potential for metastases. Four of 11 patients in this series developed metastases.