Background: Primary bone sarcomas of the hands or feet are rare lesions and poorly documented. Moreover, the prognostic determinants of bone sarcomas of the hands or feet have not been reported.
Materials and methods: The Surveillance, Epidemiology, and End Results (SEER) program database was used to screen patients with bone sarcomas of the hands or feet from 1973 to 2013, with attention paid to chondrosarcoma, Ewing sarcoma, and osteosarcoma. The prognostic values of overall survival (OS) and cancer-specific survival (CSS) were assessed using Cox proportional hazards regression model with univariate and multivariate analyses. The Kaplan–Meier method was used to obtain OS and CSS curves.
Results: A total of 457 cases were selected from the SEER database. Chondrosarcoma was the most common form of lesion in hands or feet or both, followed by Ewing sarcoma and osteosarcoma. The 5- and 10-year OS rates of the entire group were 75.7% and 66.1%, respectively. The 5- and 10-year CSS rates were 78.7% and 73.7%, respectively. Multivariate analysis revealed that age under 40 years, localized stage, low grade, surgical treatment, and first primary tumor were associated with improved OS, and decade of diagnosis, stage, grade, and surgery were independent predictors of CSS. However, no significant differences were observed in OS and CSS among patients with different primary tumor locations and tumor subtypes. Additionally, the most significant prognostic factor was whether metastasis had occurred at the time of initial diagnosis.
Conclusion: Among patients with primary bone sarcomas of the hands or feet, younger age (<40 years), localized stage, low grade, surgical treatment, and first primary tumor are favorable factors for prolonging survival.
Keywords: chondrosarcoma, Ewing sarcoma, osteosarcoma, short bone, prognosis

INTRODUCTION

Primary bone sarcomas are very rare and unfamiliar entities in the hands or feet; these tumors include chondrosarcoma, Ewing sarcoma, and osteosarcoma.1 Many studies reported that chondrosarcomas were the most frequent malignant bone tumors in the hands or feet.2,3 The most common sites of chondrosarcoma include the pelvis, proximal femur, and humerus; however, the small bones of the lower (2.2%) and upper (2.1%) extremities are very rare sites for chondrosarcoma.4 Ewing sarcoma is the second most common primary bone tumor in children and adolescents. The bones of the hands (1.4%) or feet (4%) are also uncommon sites for Ewing sarcoma. Osteosarcoma is the most common primary bone malignancy in children and young adults, primarily occurring in the metaphysis of long bones. The incidence of osteosarcoma in the short bones is extremely low (~0.9%).3 Due to the rarity of bone sarcomas at these sites, case reports and case series are the most common reports. Moreover, most of these focused on the epidemiologic data and put less value on prognosis.

To obtain insight into primary bone sarcomas of the hands and feet, the Surveillance, Epidemiology, and End Results (SEER) program database was used to screen patients with bone sarcomas of the hands or feet from 1973 to 2013, with attention paid to chondrosarcoma, Ewing sarcoma, and osteosarcoma. The emphasis was mainly placed on determining prognostic factors for overall survival (OS) and cancer-specific survival (CSS) in these patients.