Evaluation of Germline Pathogenic Variant of TP53 Gene in an Iranian Pedigree with Familial Sarcoma: A Case Report

Sarcomas are rare cancers that occur in mesenchymal tissues. The acknowledgment of genetic factors in these heterogeneous neoplasms could cause progress in diagnoses and targeted therapy. Sarcomas have two main categories: soft tissue and bone sarcoma. These cancers have been associated with some hereditary cancer syndrome like Li-Fraumeni Syndrome. In this research, we present a pedigree with familial sarcoma. Our proband is a young woman with osteosarcoma involving her upper jawbone. The patient had a family history of many cases of sarcoma, brain tumors, especially osteosarcoma; also, we considered the association of cancer predisposing syndrome and high rate of sarcomas in this family. By means of whole-exome sequencing, one pathogenic variant of <i>TP53</i> gene was recognized. Additional investigation like co-segregation analysis assessed the existence of this mutation in some of affected and unaffected family members and showed that probably this family is a case of familial Li-Fraumeni syndrome. This finding suggested that germline mutation of <i>TP53</i> gene play an important role in initiating and spreading sarcoma in this family with Li-Fraumeni syndrome.