Purpose: The role of chemotherapy (CT) and radiotherapy (RT) for management of extraskeletal osteosarcoma (ESOS) remains controversial. We examined disease outcomes for ESOS patients and investigated the association between CT/RT with recurrence and survival. Patients and methods: Retrospective review at 25 international sarcoma centers identified patients ≥18 years old treated for ESOS from 1971 to 2016. Patient/tumour characteristics, treatment, local/systemic recurrence, and survival data were collected. Kaplan-Meier survival and Cox proportional-hazards regression and cumulative incidence competing risks analysis were performed. Results: 370 patients with localized ESOS treated definitively with surgery presented with mainly deep tumours (n = 294, 80%). 122 patients underwent surgical resection alone, 96 (26%) also received CT, 70 (19%) RT and 82 (22%) both adjuvants. Five-year survival for patients with localized ESOS was 56% (95% CI 51%-62%). Almost half of patients (n = 173, 47%) developed recurrence: local 9% (35/370), distant 28% (102/370) or both 10% (36/370). Considering death as a competing event, there was no significant difference in cumulative incidence of local or systemic recurrence between patients who received CT, RT, both or neither (local p = 0.50, systemic p = 0.69). Multiple regression Cox analysis showed a significant association between RT and decreased local recurrence (HR 0.46 [95% CI 0.26-0.80], p = 0.01). Conclusion: Although the use of RT significantly decreased local recurrences, CT did not decrease the risk of systemic recurrence, and neither CT, nor RT nor both were associated with improved survival in patients with localized ESOS. Our results do not support the use of CT; however, adjuvant RT demonstrates benefit in patients with locally resectable ESOS.

Objective: We analyzed the risk factors for pulmonary metastasis from giant cell tumor of bone and aimed to discuss their therapeutic strategy and appropriate follow-up period. Methods: We analyzed 141 patients of giant cell tumor of bone. The variables analyzed included age, gender, primary site, Campanacci grading, surgical treatment on the primary lesion, radiotherapy and local recurrence. Results: Pulmonary metastasis occurred in 12 patients. The risk factors were young age, Campanacci Grade III and local recurrence. Median time from initial surgery to metastasis was 1.3 years (0-3.1 years). Among them, eight patients experienced local recurrence of the primary tumor, and the median time from initial surgery to local recurrence was 0.8 years (0.3-2.9 years). Among seven patients who underwent wide resection, three patients showed local recurrence of the soft tissue. Nine patients underwent metastasectomy for pulmonary metastases. Of three patients who did not undergo metastasectomy, one patient died of uncontrollable metastases, and two patients showed no changes in their metastatic lesions. Conclusions: Although we found a correlation between local recurrence and pulmonary metastasis, we were still unable to prevent local or metastatic recurrence by wide resection. Local recurrence and metastasis have been found within~3 years after initial surgery, and routine image examinations of the primary site and chest after initial surgical treatment should be considered for at least 3 years postoperatively.

BackgroundDermatofibrosarcoma protuberans (DFSP) may recur locally but rarely metastasizes. Fibrosarcomatous transformation in dermatofibrosarcoma protuberans (FS-DFSP) is said to have worse prognosis compared with ordinary DFSP (O-DFSP). Since DFSP rarely metastasizes, there have been few reports summarizing data on distant metastasis cases at single institution. The aim of this retrospective study is to review DFSP cases in order to analyze risk factors for metastasis.Patients and methodsThis retrospective study involved 67 patients. We analyzed O-DFSP and FS-DFSP metastasis rates, metastasis sites, time to metastasis, the relationship between frequency of local recurrence and metastasis, and the relationship between primary tumor size and metastasis.ResultsDistant metastasis was found in 5 (7.4 %) of 67 cases with DFSP. Of the five cases, the histopathological diagnosis was FS-DFSP in four cases and O-DFSP in one case. Out of five cases with metastasis, three had not recurred and two had recurred twice. No clear correlation was identified (Fisher’s exact test: p = 0.216). The primary tumor diameters in the metastatic cases were 15.0, 12.6, 20.5, 13.0, and 5.0 cm, respectively. The tumor diameters in metastatic cases were significantly larger (Fisher’s exact test: p < 0.0001).ConclusionsIn this study, we identified a stronger correlation between DFSP metastasis and tumor size. There was a high possibility that the cases with large tumors might be FS-DFSP, having high rate of metastasis and poor prognosis. In treatment of DFSP, early diagnosis before primary tumor growth and wide resection is considered important.Level of evidence V.

No abstract

Level II, prognostic study.