Clinical diagnosis, treatment and prognosis of low-grade central osteosarcoma

Abstract

Objective To summarize the clinical characteristics, imaging features, diagnosis and treatment of low-grade central osteosarcoma(LGCOS). Methods The clinical data of 34 patients with LGCOS who were pathologically diagnosed and treated from January 2008 to January 2016 in Shanghai Jiao Tong University Affiliated Sixth People's Hospital were analyzed retrospectively. A total of 34 patients included 22 males and 12 females, aged from 13 to 62 years, with a median of 40 years. Among them 28 patients were primary tumor and 6 patients were recurrent. The location of the disease was 11 patients of distal femur, 9 patients of proximal tibia, 7 patients of proximal femur, 3 patients of proximal humerus, 1 patient of ulna, radius, ilium and fibula. We summarized the clinical manifestations, imaging and pathological features, treatment and follow-up, and prognosis. Results The mainly clinical symptoms were pain and swell. The main manifestations in imaging were osteogenic, osteolytic and mixed osteogenesis. Among them, mixed osteogenesis was more common. Thirteen of 18 patients with more than 2 malignant signs in X-ray. Histology of LGCOS showed a large number of collagen fibers, relatively matured bone-like tissue, and slightly heterotypic spindle cells. Eleven of 34 patients had focal dedifferentiation components. It was rich in cells with obvious heterotypic and pathological mitotic figures. All patients underwent extensive surgical resection. The follow-up time was 1-8(3.5±1.8) years, of which 3 relapsed and 2 patients died of metastasis. In 6 recurrent patients, half of them underwent amputation. Conclusions LGCOS is a well-differentiated and low-grade malignant tumor. Its clinical features are long duration and mild symptoms. When X-ray manifests as osteogenesis and osteolysis coexist, it should be taken into account the possibility of LGCOS. CT and MRI examination is necessary to diagnose LGCOS. When the clinical characteristic and imaging suggest LGCOS, open biopsy is recommended to take. The prognosis depends on the treatment, so correct diagnosis is important. Key words: Osteosarcoma; Low grade central osteosarcoma; Diagnosis; Treatment; Prognosis