Figure 1. Histogram showing the EGFR and ALK expression patterns (Score 1+/2+/3). Biphasic expression (Score 2+/1+) was reported only for EGFR in some cases. Inside plates: overexpression of EGFR and ALK assayed by IHC (Score 2+/3+). Note the membranous/cytoplasmic staining pattern (DAB chromogen, original magnification 100×).