Osteosarcoma Arising in Noonan Syndrome/RASopathy Complex: First Case Report.

BACKGROUND

Noonan syndrome (NS) is a developmental malformation condition in the RASopathies group, characterized by variable clinical and molecular features. The syndrome is genetically heterogeneous, with the most frequent mutation found in approximately 50% of cases occurring in the PTPN11 gene. NS is reported to be associated with neurogenic, hematopoietic, melanocytic and other visceral malignancies, but osteosarcoma development has not been reported in association with NS.

CASE REPORT: Therefore, we report the first case of a male with NS who developed osteosarcoma of the mandible in a background of long-standing polyostotic fibrous dysplasia (FD) of the craniofacial bones.