Neuroendocrine and squamous colonic composite carcinoma: Case report with molecular analysis

Figure 4 Molecular analysis. A, B: KRAS mutation analysis; A: The peak at 176 bp (arrow) corresponds to the G13D mutation; B: Absent peak in the G12D mutation analysis (internal size standards at 160, 200, 248 and 300 bp; internal control amplicon peak at 267 bp for A and B); C, D: BRAF V600E mutation analysis; C: The tumor is negative for the BRAF V600E mutation as shown by the absence of a peak at 101 bp (arrow); D: BRAF V400E positive control with peak at 101 bp (internal size standards at 100, 140, 150, 160 and 200 bp; internal control amplicon peak at 171 bp for C and D); E: Microsatellite instability testing demonstrates a microsatellite-stable tumor, top; normal tissue, bottom (internal size standards at 120, 140, 160 and 200 bp).