A case of recurrent giant cell tumor of bone with malignant transformation and benign pulmonary metastases

Giant cell tumor (GCT) of bone is a locally destructive tumor that occurs predominantly in long bones of post-pubertal adolescents and young adults, where it occurs in the epiphysis. The majority are treated by aggressive curettage or resection. Vascular invasion outside the boundary of the tumor can be seen. Metastasis, with identical morphology to the primary tumor, occurs in a few percent of cases, usually to the lung. On occasion GCTs of bone undergo frank malignant transformation to undifferentiated sarcomas. Here we report a case of GCT of bone that at the time of recurrence was found to have undergone malignant transformation. Concurrent metastases were found in the lung, but these were non-transformed GCT

Dedifferentiated chondrosarcoma: A report of the clinicopathologic features and outcomes of 16 cases treated at a single institution.

e23500 Background: Dedifferentiated chondrosarcoma (DCS) is a rare and aggressive malignancy with a poor prognosis. The purpose of this investigation was to assess the clinicopathological features and outcomes of DCS patients treated at a single institution. Methods: This study was a retrospective review over a consecutive twenty-year period. Data including treatment details and outcomes were recorded. Results: A total of 16 cases from 2000 to 2018 were reviewed. The median age was 62 years (IQR, 52-69 years) and the majority of DCS arose in the femur (50%, n = 8) and pelvis (25%, n = 4). Fourteen (88%) cases received limb salvage/wide margin resection (n = 13) or intralesional surgery (n = 1). For all DCS, the median estimated overall survival (OS) was 46 months (95% CI, 1-90 months) with both a five and ten-year survival probability of 32%. On Kaplan-Meier analysis there was no difference between operative versus nonoperative management (p = 0.747), surgery alone versus surgery/chemotherapy (p = 0.265), nor surgery alone versus surgery/chemotherapy/radiation (p = 0.698). Conclusions: Our findings confirm the poor prognosis of DCS patients, though with a five-year estimate of 32%, higher than previous literature. Together with existing literature, our data may enable future strategic recommendation of DCS patients. </jats:p

Comparison of clinicopathological features and outcomes in patients with primary leiomyosarcoma of bone and soft tissue.

e23526 Background: Leiomyosarcoma is a rare malignancy that may occur in bone. This investigation described the characteristics and outcomes of primary leiomyosarcoma of bone (PLB) compared to soft tissue leiomyosarcoma (SLMS). Methods: This study was a retrospective review using the Surveillance, Epidemiology, and End Results (SEER) database from 1975 to 2016. Continuous and categorial variables were described, and Cox regression were used to identify factors of prognostic significance. Results: Seven thousand five-hundred two patients met inclusion criteria. Seventy-four (1%) were PLB and 7428 (99%) were SLMS. On multivariable analysis for high-grade SLMS radiation (neoadjuvant: HR, 0.56; 95% CI, 0.4-0.8; p = 0.003, and adjuvant: HR, 0.75; 95% CI, 0.6-0.9; p = 0.008) and surgery (procedure specific) improved DSS, while age (HR, 1.013; 95% CI, 1.0-1.1; p &lt; 0.001), tumor size greater than or equal to 5 cm (HR, 3.16; 95% CI, 2.3-4.2; p &lt; 0.001), abdomen/pelvis/trunk/thorax tumors (HR, 1.31; 95% CI, 1.1-1.6; p = 0.006), and distant metastases at presentation (HR, 2.6; 95% CI, 2.1-3.3; p &lt; 0.001) negatively influenced DSS. Conclusions: Radiation and surgery positively influence survival in high-grade SLMS while chemotherapy appears to have no benefit. Surgery alone appears to lower the mortality risk in PLB. </jats:p

Function After Injection of Benign Bone Lesions with a Bioceramic

BACKGROUND: A novel calcium sulfate–calcium phosphate composite injectable bone graft substitute has been approved by the FDA for filling bone defects in a nonweightbearing application based on preclinical studies. Its utility has not been documented in the literature. QUESTIONS/PURPOSES: We therefore determined postoperative function and complications in patients with benign bone lesions treated with this bioceramic. METHODS: We retrospectively reviewed all 56 patients with benign bone lesions treated with the bioceramic from 2006 to 2008. There were 29 male and 27 female patients with an average age of 17.6 years (range, 4–63 years). They were treated for the following diagnoses: unicameral bone cyst (13), aneurysmal bone cyst (10), nonossifying fibroma (eight), fibrous dysplasia (five), enchondroma (four), chondroblastoma (four), and other (12). We obtained a Musculoskeletal Tumor Society (MSTS) functional evaluation on all patients. The minimum followup was 26 months (average, 42 months; range, 26–57 months). RESULTS: The average MSTS score was 29 (range, 20–30). Most patients returned to normal function. There were three local recurrences, all of which were treated with repeat injection or curettage. Two patients had postoperative fractures treated in a closed manner. Two patients had wound complications, neither of which required removal of the graft material. CONCLUSION: Patients treated with this material reported high MSTS functional scores more than 24 months after operative intervention and experienced low complication rates. We believe the novel bioceramic to be a reasonable treatment option for benign bone lesions. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence