Dedifferentiated chondrosarcoma of the thumb: a case report

Dedifferentiated chondrosarcoma of the middle finger arising from a solitary enchondroma: A case report

BACKGROUND

Dedifferentiated chondrosarcoma (DDCS) accounts for 10% of all chondrosarcomas and has the poorest outcome, with a 5-year survival rate of 7%-25%. DDCS commonly occurs in the femur and pelvis, whereas DDCS of the finger is extremely rare. Furthermore, the histological findings of preexisting solitary enchondroma samples are important and valuable for diagnosing malignant transformations.

CASE SUMMARY

We report our experience with DDCS in the proximal phalanx of the left middle finger of an 87-year-old woman. She had undergone surgery for enchondroma, with curettage and artificial bone grafting, 11 years ago, in the same location. Several years after the primary surgery, the left middle finger gradually started to enlarge, and the growth speed increased in the past year. Plain radiographs showed an expansive osteolytic lesion with calcifications and residual grafting material. Owing to the suspicion of malignancy, we performed ray amputation. Histological findings revealed an abrupt transition between the low-grade chondrosarcoma and dedifferentiated sarcoma components. The dedifferentiated components showed the features of a high-grade undifferentiated pleomorphic sarcoma. The patient was diagnosed with DDCS arising from a preexisting enchondroma. She had no local recurrence or distant metastasis and died of pneumonia 6 years and 10 months after the second surgery.

CONCLUSION

The histological findings of a precursor lesion showed a typical enchondroma, suggesting that DDCS can arise from enchondroma.

Acral Dedifferentiated Chondrosarcoma: Report of a Case Arising in the Proximal Phalanx of the Fourth Finger

Dedifferentiated chondrosarcoma is a well-recognized entity, but its occurrence in the distal extremities is exceedingly rare. We present the case of a 49-year-old woman who experienced local recurrence of an "enchondroma" of the proximal phalanx of the fourth finger of the left hand, which had been initially treated with intralesional curettage at another hospital 4 years before, and 1 year before for a local recurrence. The imaging findings indicated an aggressive behavior, and an incisional biopsy showed a highly cellular proliferation of spindle and pleomorphic elements without evidence of matrix production intermixed with few fragments of a well-differentiated cartilaginous neoplasm with bland cellular atypia, focal nuclear hyperchromatism, and binucleation. An isocitrate dehydrogenase 2 R172S mutation was detected. The final diagnosis was dedifferentiated chondrosarcoma. Despite amputation of the fourth finger, the patient developed lung metastases and further local relapse. Recurrent cartilaginous tumors of the extremities should not be underestimated and should be followed in view of the possible acquisition of aggressive clinical behavior.

A case of dedifferentiated chondrosarcoma arising in the cricoid cartilage that mimicked an aneurysmal bone cyst

Dedifferentiated chondrosarcoma of the larynx is a rare and highly malignant tumor. We present the report of a 59-year-old man with dedifferentiated laryngeal chondrosarcoma, which was difficult to diagnose even under microscopic examination. The original diagnosis was an aneurysmal bone cyst, and the final diagnosis was established only after careful consideration of the imaging, surgical, and microscopic findings. In clinical practice, there are many similarities between dedifferentiated chondrosarcoma and aneurysmal bone cysts. Furthermore, it is difficult to identify dedifferentiated laryngeal chondrosarcoma with a giant-cell malignant mesenchymal component. This report describes our experience and discusses this phenomenon.

Dedifferentiated chondrosarcoma of the cervical spine: a case report

Dedifferentiated chondrosarcoma (DDCS) is a rare and aggressive bone tumor with poor prognosis. Primary DDCS of the mobile spine is extremely rare, particularly in the cervical spine. We herein describe a first case of cervical DDCS in an 81-year-old male presenting with a slowly growing mass. Radiographs showed an expansion of the cortical contour of the C2 lamina and a soft tissue mass with punctate calcification. Magnetic resonance imaging demonstrated a lobulated lesion expanding over the entire lamina and pedicles of C2 with the tumor protuberant to the adjacent soft tissue. A complete tumor resection was performed. Histologically, the majority of the tumor was a low-grade chondrosarcoma component. However, atypical spindle cells that had proliferated in a fascicular pattern with a collagenous stroma, mimicking fibrosarcoma, were focally observed without a transitional zone, and these features confirmed that the tumor was DDCS.

FREE FIBULAR GRAFT RECONSTRUCTION FOLLOWING RESECTION OF CHONDROSARCOMA IN THE FIRST METACARPAL

Chondrosarcoma is most frequently present in the pelvis and long bones and rarely seen in the bones of the hand. Traditionally the treatment of choice for involvment of the hand is ray amputation, however this causes significant functional deficit if there is thumb involvement. There are limited cases in literature of resection of thumb chondrosarcoma with restoration of function. We present a case of high grade chondrosarcoma of the first metacarpal treated with resection and free fibular graft reconstruction. We report excellent functional outcome with this procedure.

Tumours of the hand: a review on histology of bone malignancies

Malignant bone tumours of the hands are uncommon. Although almost all lesions that occur in other parts of the skeleton can also affect the hands, their frequency, distribution and clinical characteristics differ. This review focusses on the histology of these tumours and gives an overview of the main differential diagnoses. Close correlation to radiologic and clinical features usually leads to the correct diagnosis.

Malignant Natural-Killer cell neoplasm presenting as a mucous cyst on the distal interphalangeal joint of the finger

This case report describes a very rare and highly malignant type of lymphoma, which presents as a mucous cyst on the finger. The cyst was excised and the specimen pathohistologically analyzed. The analysis revealed the presence of a Natural-Killer cell neoplasm. This case illustrates and stresses the importance of a pathohistological examination when doubts arise about the initial diagnosis of a benign tumorous lesion.