When evaluating the IHC profile of the total 38 cases diagnosed with NEC and NET, the following results were observed: CK AE1/AE3 was positive in 21 of 24 cases (87.5%), CK7 was positive in 10 of 19 cases (52.6%), CK20 was positive in one of 13 cases (7.7%), chromogranin A was positive in 21 of 30 cases (70%), synaptophysin was positive in 30 of 33 cases (90.9%), CD56 was positive in 26 of 28 cases (92.9%), CDX2 was positive in 4 of 7 cases (57.1%), and TTF1 was positive in 19 of 32 cases (59.4%). Here, TTF1 is linked to neuroendocrine carcinoma.