Chondroblastoma with atypical features

Abstract

Chondroblastoma (CB) is a rare bone tumour usually occurring in long bones of males in the second decade. Though these are considered benign, rare cases show aggressive behaviour and metastases. However, there are no defined histological criteria to diagnose aggressiveness, except soft tissue (ST) infiltration. With the identification of specific immunohistochemical and genetic signatures, recent research has nurtured the concept of malignant CB and raised concerns that malignant CBs are being frequently misdiagnosed. Here we report a case of a CB with unusual features, in a 62-year-old woman which includes rare location in the scapula, recurrence following a long period after excision, extensive soft tissue invasion, and predominant small round cell morphology. This case intends to add to the limited literature on aggressive CB as well as to the evolving concept of malignant CB. The case also highlights the importance of follow up of patients with CB preventing mutilating surgery.