SYP and neuroendocrine neoplasm: In one large study, however, there was no increase in sensitivity for detecting NED among neuroendocrine neoplasms with addition of INSM1 to a panel of markers that included both synaptophysin and chromogranin A, except in the case of neuroendocrine carcinomas, where the combination of INSM1/synaptophysin resulted in more positive cases than synaptophysin/chromogranin A (94.4 versus 91.6%).14