PTEN and obstructive sleep apnea syndrome: The frequency of genomic loss at 10q/PTEN as assessed by OSA (10/16; 62.5%) was much higher in CRC with prominent CSC-like expansion, as defined by the PTEN IHC pattern, than in cases with uniform PTEN expression (1/16; 6.3%, p = .0007) (Fig 4A).