EGFR and neoplasm: EGFR gene amplification was associated with deep invasion (pT3–pT4 versus pT1–pT2; Fisher’s exact test, p = 0.020; OR 3.49, 95 % CI: 1.17–10.4) and it was more commonly detected in stage III–IV tumours than in stage I–II tumours (Fisher’s exact test, p = 0.024; OR 2.55, 95 % CI: 1.18–5.51).