ABCG2 and neoplasm: Notably, unspecific low-to-moderate expression of ABCB6 (median score 8, range: 8–9), ABCG2 (median score 3, range: 1–4), FECH (median score 4, range: 1–8) and CPOX (median score: 1, range: 0–1) was also found in all nine fluorescent cortex samples lacking tumor invasion (Figure 3).