EGFR and neoplasm: In all, 60.0% (18 out of 30) of the tumours with an increased EGFR copy number presented hemi- or homozygous deletion of PTEN (87.5% of the SDCs) in contrast to only 17.1% (27 out of 158) PTEN deletion in EGFR-negative tumours (P<0.001).