EGFR and neoplasm: Claudin-4 negative to positive conversion in the metastases was significantly associated with tumor size (p = 0.015; 11/14 versus 31/72), whereas negative to positive conversion of EGFR was associated with negative PR status (p = 0.046; 8/8 versus 46/75) and high MAI (p = 0.047; 8/8 versus 47/75).