Cell-free DNA from plasma as a promising alternative for detection of gene mutations in patients with Maffucci syndrome

Maffucci syndrome (MS, OMIM 166000) is an extremely unusual, nonhereditary, multisystemic disorder that is characterized with multiple enchondromas and vascular lesions, most of which are spindle cell hemangiomas. Complications of MS, such as bone deformities and dysfunction caused by enchondromas, usually increase during childhood and adolescence. Malignant transformation of enchondromas and other malignancies are the most severe complications. MS is caused by somatic mosaic IDH1/2 mutations, 65% of which are the IDH1 p.Arg132Cys variant. Due to its rarity, there is no international consensus for the most appropriate treatment option of MS. Here, we report a case of a female patient presenting with multiple enchondromas and spindle cell hemangiomas (SCHs) on bilateral hand and feet diagnosed as MS. A detailed clinical, pathological and genetic diagnosis of MS was rendered. Integrative Genomics Viewer (IGV) visualization of next-generation sequencing (NGS) data revealed the consistent detection of the low-frequency somatic IDH1 p.Arg132Cys mutation between SCH tissue and cystic blood-derived cfDNA. This is the first successful molecular diagnosis of MS complicated with SCH utilizing minimally invasive cfDNA techniques. We suggest that cfDNA sequencing could potentially be used as an alternative, reliable and sensitive method to identify molecular information for genetic diagnosis and for future targeted therapies of MS.