Radiologic case study. Clear-cell chondrosarcoma

Clear cell chondrosarcoma of bone: long time follow-up of 18 cases

INTRODUCTION

Clear cell chondrosarcoma is a variant of conventional chondrosarcoma behaving as low grade malignant bone tumor. We reviewed our cases of clear cell chondrosarcoma with the aim to assess the best diagnostic and curative approach to this rare tumor.

MATERIALS AND METHODS

We report 18 cases of clear cell chondrosarcoma treated at the authors' institution. Pertinent clinical information, pre and postoperative serum alkaline phosphatase (SAP) level were obtained from the patients charts. Available imaging studies including plain roentgenograms, computed tomography (CT) images (in 6 patients) and magnetic resonance imaging (MRI) images (in 2 patients).

RESULTS

Eight cases were firstly treated in other institutions, seven with one or more curettage, while one, presented with pathologic fracture, was treated with repeated osteosynthesis. Of the seven patients treated with curettage, five were referred with local recurrence, the mean time between surgical treatment and local recurrence was 52.2 months (from 12 to 132). The other two patients were curetted out 4 and 1 month before, respectively, and were then referred to us to decide about further treatment after incidental diagnosis. Of these cases, three (37.5%) recurred again after our treatment and two of them presented with late bone metastases. Eight patients were originally treated with wide (six) or marginal (two) surgical margins by us. Among them only one proximal humerus (wide margins) had local recurrence 26 months from the first operation. Two patients underwent curettage in our institution, and one of them had a local recurrence. Pre-operative SAP level were obtained in 17 patients. Among them, 11 patients had high pre-operative SAP level (64.7%) and 6 cases were normal. Post-operative SAP levels were obtained in nine patients. After removal of the tumors; SAP levels decreased to normality in seven of the nine patients with high pre-operative SAP. In the other two patients, although the SAP levels were normal, post-operative SAP levels were decreased.

CONCLUSION

Serum alkaline phosphatase can be used as a good tumor marker in diagnosis and follow-up. Due to the occurrence of local recurrences and distant metastasis after curettage, we suggest surgical treatment with "en bloc" resection from the first presentation.

Unresolving hip tendonitis leads to discovery of malignant tumor

OBJECTIVE

To discuss a case of malignant bone tumor in the left hip of a patient who sought treatment following a tennis injury.

CLINICAL FEATURES

A 27-year-old male patient visited a chiropractic clinic 6 months after a twisting injury to his left hip which occurred while playing tennis. His pain had remained moderate in intensity and intermittent to frequent in frequency since it originated but became more intense the week prior to his visit.

INTERVENTION AND OUTCOME

The patient was diagnosed with a tendonitis/bursitis and received 3 weeks of treatment. Care consisted of various forms of passive modalities to reduce pain and inflammation, as well as hip mobilization and tissue stretching. Plain film examination was then performed, due to lack of progress, and revealed a possible chondroblastoma of the femoral head. The patient was referred to his primary care physician (PCP) for follow-up imaging. Surgical resection of the lesion occurred approximately 2 months later. Biopsy of the resected cells confirmed a new diagnosis of clear cell chondrosarcoma. A computed tomography (CT) scan of the chest was performed to rule out metastasis to the lungs. Regular follow-up care and imaging continued and revealed, 9 months following, that the femoral head lesion had returned and hip replacement surgery would be needed.

CONCLUSION

Tendonitis, bursitis, and sprains commonly occur following sports-related trauma to the appendicular skeleton. A conservative trial of care should be performed on suspected soft tissue injuries. However, when lack of improvement occurs within the first month, further examination, special studies, or referral are warranted to ensure a proper diagnosis and to rule out a pathological condition.