Proteus syndrome with syringohydromyelia and arachnoid cyst

Excerpt

The authors make a good review of the main clinical and genetic aspects of Proteus syndrome. They also describe new neuroimaging findings with clinical significance that must be added to the variety of abnormalities in these rare multi-organic neurocutaneous syndrome. With regard to molecular genetics, Zhou et al. [3] reported a boy with congenital hemihypertrophy, epidermoid nevi, macrocephaly, lipomas, arteriovenous malformations, and normal intellect. The patient had the clinical diagnosis of Proteus-like syndrome. Sequence analysis of DNA from peripheral blood revealed heterozygosity for a single base transversion resulting in an Arg 335 to Ter substitution of the phosphatase and tensin homolog (PTEN) gene product, whereas analysis of the DNA from nevus, lipoma, and arteriovenous mass also revealed heterozygosity for Arg 130 to Ter. The former mutation had been reported in patients with Cowden syndrome, whereas the latter mutation had been reported in individuals with Bannayan–Zonana syndrome. The authors postulated that the second hit, Arg 130 to Ter, occurred early in embryonic development and may even represent germline mosaicism. Thus, PTEN may be involved in Proteus-like syndrome with its implications for cancer development in the future. Five unrelated patients with Proteus syndrome had no demonstrable mutations in PTEN. …