KRAS and neoplasm: The combination of cetuximab and PBR extract produced a statistically significant reduction in tumor volume, compared with that of cetuximab alone, in the KRAS-mutant SW480 xenografts (mean tumor volume on day 26 = 3344 ± 572 mm3 vs. 1870 ± 571 mm3, cetuximab vs. cetuximab + PBR, p = 0.011) (Figure 5).