Osteofibrous Dysplasia with Rhabdoid Elements in a 38-Year-Old Man with Spontaneous Regression Over Five Years: A Case Report.

CASE: A 38-year-old man presented with multifocal, partially confluent osteolytic lesions in the proximal dia-meta-epiphyseal region of the proximal aspect of the left tibia, which had been found incidentally when a radiograph was made after a rotational knee injury. When the results of a percutaneous core needle biopsy proved inconclusive, an open biopsy was performed. Osteofibrous dysplasia (OFD) with scattered groups of plump cells with a rhabdoid phenotype, shown to express both vimentin and pan-cytokeratin, was found. Because the lesion was an incidental finding, we decided to proceed with observation. Three months after the open biopsy, imaging showed marked regression of the lesion; there was nearly complete normalization 5 years later. CONCLUSION: To our knowledge, there has been only 1 prior reported case with these pathologic features, and there have been no reports of complete spontaneous regression in an adult patient with OFD. Treatment recommendations for OFD and for OFD-like adamantinoma range from observation to aggressive resection.

FDG uptake in a rheumatoid nodule with imaging appearance similar to a malignant soft tissue tumor.

Partial-body F-18 FDG PET/CT was performed in a 40-year-old woman with a soft tissue tumor at the left elbow. She had rheumatoid arthritis for several years. PET/CT showed moderate FDG uptake (SUV max. 4.2) in the known soft tissue lesion. The tumor was resected and histology revealed rheumatoid granulomas with bursitis.

Recurrent aggressive chondrosarcoma of the middle phalanx of the index finger: excision and reconstruction with an osteocartilaginous allograft.

INTRODUCTION: Chondrosarcomas are malignant tumours and need to be treated aggressively including ablative surgery. Bovée et al. and Mankin have recently drawn attention to a less aggressive behaviour of chondrosarcomas of the phalanges compared with those of other localizations including the metacarpals. MATERIALS AND METHODS: An 12 year follow-up of a patient with a chondrosarcoma of the middle phalanx of the index finger is presented. The lesion was curetted initially, and a repeat curettage was performed 4 years later. Finally, 8 years later the phalanx was excised and reconstructed with an osteocartilaginous allograft. Histologically, the lesion changed from a chondrosarcoma grade I to grade II. RESULT: The patient continues to be free of recurrence and metastases 4 years after the final resection. CONCLUSION: The potential for systemic disease of chondrosarcomas of the phalanges is probably much lower than in chondrosarcomas of other localizations, and therefore digit-sparing techniques may be considered rather than ablative procedures.

Osteosarcoma of the pelvis: experience of the Cooperative Osteosarcoma Study Group.

PURPOSE: To define patients and tumor characteristics as well as therapy results, patients with pelvic osteosarcoma who were registered in the Cooperative Osteosarcoma Study Group (COSS) were analyzed. PATIENTS AND METHODS: Sixty-seven patients with a high-grade pelvic osteosarcoma were eligible for this analysis. Fifteen patients had primary metastases. All patients received chemotherapy according to COSS protocols. Thirty-eight patients underwent limb-sparing surgery, 12 patients underwent hemipelvectomy, and 17 patients did not undergo definitive surgery. Eleven patients received irradiation to the primary tumor site: four postoperatively and seven as the only form of local therapy. RESULTS: Local failure occurred in 47 of all 67 patients (70%) and in 31 of 50 patients (62%) who underwent definitive surgery. Five-year overall survival (OS) and progression-free survival rates were 27% and 19%, respectively. Large tumor size (P =.0137), primary metastases (P =.0001), and no or intralesional surgery (P <.0001) were poor prognostic factors. In 30 patients with no or intralesional surgery, 11 patients with radiotherapy had better OS than 19 patients without radiotherapy (P =.0033). Among the variables, primary metastasis, large tumor, no or intralesional surgery, no radiotherapy, existence of primary metastasis (relative risk [RR] = 3.456; P =.0009), surgical margin (intralesional or no surgical excision; RR = 5.619; P <.0001), and no radiotherapy (RR = 4.196; P =.0059) were independent poor prognostic factors. CONCLUSION: An operative approach with wide or marginal margins improves local control and OS. If the surgical margin is intralesional or excision is impossible, additional radiotherapy has a positive influence on prognosis.