Comparing paired tumour and normal tissue samples, we found a significantly lower level of EGFR/HER1 in tumour compared to normal tissue both among premenopausal (8 of 8 patients, individual ratio 0.10 (95% CI: 0.047-0.23), P=0.012) as well as postmenopausal (22 of 22, individual ratio: 0.13; CI: 0.09-0.20, P<0.001) women. Here, EGFR is linked to neoplasm.