SYP and neoplasm: Synaptophysin-chromograninA co-expression was observed in 34% of our MN-NEs and in 5/92 (5%) neoplasms from the literature [2–4, 12, 15, 18, 19, 23, 30, 33, 34, 36, 38–42, 44, 46, 47, 49, 50, 54] (see Table 1 and 2), suggesting that the dichotomy in the synaptophysin-chromograninA expression is a common finding in these neoplasms and contrasts sharply with the expression rates in PanNETs, in which chromograninA labels 91% of the synaptophysin positive tumors [52].