Fig. 4

The NETest accuracy in Gastric NEN identification. The NETest was 97% accurate (normal score 61/ 63) in controls (the two elevated NETest scores were 20% [borderline] and 27%, in two women aged 28 and 42 with no history of co-morbidities, or medications). NETest score was 100% (16/16) accurate for the identification of histologically confirmed macroscopic disease (both endoscopy and histology-positive). Twenty-five cases were histology-positive (16 with macroscopic and 9 microscopic disease). In all (25/25), the NETest was positive. Thirty subjects were endoscopy-negative (no detectable lesions). In these, the NETest was within normal range in 43% (13/30); but nine had a microscopic disease histologically confirmed. Twenty-one individuals were negative on last histological examination (negative polypectomy margin, or gastric biopsy, or post total-gastrectomy); 13 had NETest within normal range (62%). Twenty-one subjects had no detectable lesions by gastroscopy and tested negative for NEN on last histological examination, thirteen were NETest-negative (62%). The NETest was 100% accurate for identifying microscopic disease (9/9) (no lesions detectable on gastroscopy, but confirmed by histology [positive]: 5 with positive polypectomy margin and 4 positive on random gastric biopsy). Abbreviations: endoscopy-ve = endoscopy-negative; endoscopy+ve = endoscopy-positive; histology-ve = histology-negative; histology+ve = histology-positive