Figure 4. Comparison of the 51 marker gene signature with Chromogranin A (CgA) for detecting GEP-NENs.

A) CgA levels were significantly elevated in the GEP-NEN group (n = 176; *p<0.002) but an overlap with normal values was identified. B) Comparison of the PCR-based approach with CgA protein measurement identified that call rates were significantly higher for the PCR-based test (*p<0.0005, χ² = 12.3). The PCR blood test was significantly more accurate than measurement of CgA levels to detect GEP-NENs. ULN = upper limit of normal (19U/L – DAKO).