Nasralla et al. (1992) studied the relation between epidermal growth factor levels and estrogen and progesterone receptors in 132 primary breast cancer tissue specimens. An inverse significant correlation was observed between ER and PR levels vs. epidermal growth factor receptor levels in tumors of post-menopausal women. No such correlation could be seen in pre-menopausal patients. While EGFR positive tumors showed no significant difference in the levels of ER and PR in premenopausal and postmenopausal women, EGFR negative tumors showed a significantly higher value in the postmenopausal women.

Kharrat et al. (2007) genotyped 252 healthy individuals and 118 female breast cancer patients from Kuwait and Tunisia for the polymorphic AC repeat in intron 1 of the EGFR gene. Both the Kuwaiti and Tunisian populations were found to be very similar to each other in terms of allelic and genotypic frequencies in both control and patient groups. However, when the results were compared to those reported from other populations, several interethnic differences could be noted. The most frequent allele noted in this study was allele 17, while in Europeans and Asians, it was allele 16 and 20, respectively. Comparing the breast cancer cases to 123 healthy women, a strong association was found for allele 18 with susceptibility to breast cancer. This also contrasted with reports from Asian populations, where allele 16 was identified as the risk allele.

El Hamdani et al. (2010) evaluated the frequency of point mutations in the EGFR gene to assess the potential use of tyrosine kinase inhibitors in clinical treatment and the use of EGFR, p16INK4a and E-cadherin as biomarkers in cervical cancer diagnosis with immunohistochemistry. Of 53 patient specimens of cervical cancer, 79% (42/53) were HPV positive and the HPV types more closely associated with risk were HPV 16 and 18. In all specimens, no mutation affecting the EGFR kinase domain in exons 18 through 21 was observed. Expressions of EGFR, p16INK4a and E-cadherin were detected in 89% (47/53), 92% (49/53) and 79% (42/53) of all specimens respectively. El Hamdani et al. (2010) concluded that treatment of cervical cancer with TKIs may not be effective and that the identification of other EGFR inhibitors is yet needed.

Naji et al. (2010) studied 60 specimens of nasopharyngeal carcinoma (NPC) to assess the presence of EGFR mutations in exons 18 and 21. Again, there no mutations detected in the EGFR kinase domain in these exons in all samples analyzed. Sequence analysis of the EGFR-TK domain, revealed the presence of a G2607A polymorphism at exon 20. The genotypes AA and GA were found, respectively, in 39 (65%) and 16 (26.6%) cases. Statistical analysis showed no difference between the polymorphism and either gender or age of patients.

[See: Kuwait > Kharrat et al., 2007].