GIANT CELL TUMOR OF BONE: A MULTICENTER EPIDEMIOLOGICAL STUDY IN BRAZIL.

Introduction: Giant cell tumor of bone (GCTB) mainly affects young adults' long bone epiphyses, threatening bone strength and joint function. Surgery is the primary treatment, although post-surgery recurrence is significant. This study analyzes patient profiles, treatments, and outcomes for GCTB in Brazil.

Expression of neurotrophins and their receptors in primary osteosarcoma.

Objective: to determine the expression of neurotrophins and their tyrosine-kinase receptors in patients with osteosarcoma (OS) and their correlation with clinical outcomes.

Methods: we applied immunohistochemistry to biopsy specimens of patients consecutively treated for primary OS at a single institution between 2002 and 2015, analyzing them for expression receptors of tyrosine kinase A and B (TrKA and TrKB), neural growth factor (NGF) and brain derived neurotrophic factor (BDNF). Independently, two pathologists classified the immunohistochemical markers as negative (negative or weak focal) or positive (moderate focal/diffuse or strong focal/diffuse).