SYP and neoplasm: Many studies investigated the prognostic impact of neuroendocrine differentiation in gastrointestinal carcinomas [12,14,17,18,19,22,23,24], and all studies showed that the expression of neuroendocrine markers such as synaptophysin is linked to a poor prognosis when the tumor has a histological pattern suggestive of neuroendocrine differentiation in H&E-stained sections.