EGFR and collecting duct carcinoma: 6. Since both HCC and BDC express epidermal growth factor receptors (EGFR), we hypothesized that EGFR is a driver of these diseases, and investigated a combination of chemotherapy with EGFR blockade in the form of the TKI erlotinib, based on previously reported erlotinib studies by Philip et al. 10, 11.