Mosaic alterations of PTEN, corresponding either to nucleotide variations, genomic rearrangements or 10q23 microdeletions encompassing the PTEN locus, have already been reported in several patients exhibiting syndromic features pathognomonic of PTEN hamartoma tumor syndrome (PHTS), such as macrocephaly, Lhermitte-Duclos Disease, mucosal papillomatous lesions, hamartomatous polyposis and thyroid goiter [8–11]. This evidence concerns the gene PTEN and PTEN hamartoma tumor syndrome.