Telengiectatic osteosarcoma of mandible with special emphasis on immunohistochemical and molecular characteristics: A case report with review of literature

Telangiectatic osteosarcoma (TOS) is an uncommon pathology accounting for about 0.4%–12% of all osteosarcomas with predilection for younger adults. It is most frequently seen in the metaphysis of long bones, appearing as painful osteolytic mass that histopathologically characterized by dilated, blood‐filled vascular spaces lined by malignant osteoblasts along with osteoid formation. It has exchangeable clinical, radiological and pathological features with benign lesions like aneurysmal bone cyst and giant cell tumour of bone as well. Thus, delineating this malignancy from its benign counterparts is a crucial part in the therapeutic management.To report a case of telengiectatic osteosarcoma of jaw in a 17 year old female patient with special highlights on molecular diagnostics and therapeutic modules.A panel of immunohistochemical markers comprising of SATB2, CDK4, MDM2, panCK, CD31, desmin, NKX2.2 and TLE1 were employed in combination with fluorescent in‐situ hybridization to detect the prevalence of rearrangement in CDK4 and MDM2 genes.On immunohistochemistry, the neoplastic cells were strongly positive for SATB2 and negative for CDK4, MDM2, panCK, CD31, desmin, NKX2.2 and TLE1. Fluorescent in‐situ hybridization of CDK4 and MDM2 genes was also negative.Considering its rarity in jaws combined with clinicopathological overlap with other benign pathologies, diagnosis of this entity is crucial in treatment planning and prognostic significance. Moreover, only five cases of TOS have been reported so far in the craniofacial region. Here, we have reported the sixth case of its kind with detailed clarification pertaining to its immunohistochemical and molecular aspects.