Aim and purpose. The clinical management of osteosarcoma differs significantly from that of chondrosarcoma;. Therefore it is extremely important to diagnose these two types of bone tumour accurately. In the absence of a specific marker, differential diagnosis by histochemistry is sometimes impossible, especially between chondroblastic osteosarcoma and conventional chondrosarcoma. The aim of the study was to find an useful diagnostic marker, simple to use for distinguishes chondroblastic osteosarcoma from conventional chondrosarcoma. Method. We analysed 165 bone sarcomas by immunohistochemical staining of tissue microarrays for expression of the galectin-1 (GAL1) lectin and by Western Blot experiments. Results. We found that GAL1 was abundant in normal human osteoblasts from benign proliferations and in osteosarcomas, including chondroblastic osteosarcomas, but not in chondrosarcomas. There was a highly significant statistical difference in the percentage of stained cells (p<10-4) and in the staining intensity (p<10-3) of chondroblastic osteosarcomas compared to conventional chondrosarcomas. This discriminatory potential of GAL1 staining for osteosarcoma-derived tumours was confirmed by western blotting. We propose a diagnostic test for bone tumours that takes into account the optimal discriminative values for the percentage of cells stained and the intensity of staining. The positive and negative predictive values were 85.7% (trust interval of 63.7-97%) and 90% (trust interval of 80-95.9%), respectively, demonstrating the pertinence of the test. Conclusion. Altogether, our data indicate that GAL1 is a powerful diagnostic marker that distinguishes chondroblastic osteosarcomas from conventional chondrosarcomas

Aims

Low-grade central osteosarcoma (LGCOS), a rare type of osteosarcoma, often has misleading radiological and pathological features that overlap with those of other bone tumours, thereby complicating diagnosis and treatment. We aimed to analyze the clinical, radiological, and pathological features of patients with LGCOS, with a focus on diagnosis, treatment, and outcomes.

Aims

Bone metastasis ultimately occurs due to a complex multistep process, during which the interactions between cancer cells and bone microenvironment play important roles. Prior to colonization of the bone, cancer cells must succeed through a series of steps that will allow them to gain migratory and invasive properties; epithelial-to-mesenchymal transition (EMT) is known to be integral here. The aim of this study was to determine the effects of G protein subunit alpha Q (GNAQ) on the mechanisms underlying bone metastasis through EMT pathway.

Aims

The purpose of this study was to clarify the clinical behaviour, prognosis, and optimum treatment of dedifferentiated low-grade osteosarcoma (DLOS) diagnosed based on molecular pathology.

Aims

Myxofibrosarcomas (MFSs) are malignant soft-tissue sarcomas characteristically presenting as painless slowly growing masses in the extremities. Locally infiltrative growth means that the risk of local recurrence is high. We reviewed our experience to make recommendations about resection strategies and the role of the multidisciplinary team in the management of these tumours.

There are eight reported cases in the literature of osteosarcomas secreting β-hCG. Our primary aim was to investigate the rate of β-hCG expression in osteosarcoma and attempt to understand the characteristics of osteosarcomas that secrete β-hCG. We reviewed 37 histopathology slides (14 biopsies and 23 surgical specimens) from 32 patients with osteosarcoma. The slides were retrospectively stained for β-hCG expression. Patient and tumour characteristics, including age, gender, tumour location, subtype, proportion of necrosis, presence of metastases and recurrence were recorded. A total of five of the 32 tumours were found to be positive for β-hCG expression (one strongly and four weakly). This incidence of this expression was found in tumours with poor histological response to neoadjuvant chemotherapy.

The use of β-hCG expression as a diagnostic, prognostic or follow-up marker is questionable and needs further investigation with a larger sample size.