The Expression of Chromogranin A, Syanptophysin and Ki67 in Detecting Neuroendocrine Neoplasma at High Grade Colorectal Adenocarcinoma

BACKGROUND: Neuroendocrine neoplasm (NEN) is an epithelial cell neoplasm that can give a histopathological appearance resembling high-grade colorectal adenocarcinoma. Immunohistochemical assays with specific neuroendocrine markers of chromogranin A and synaptophysin are required to establish a definite diagnosis of NEN.
AIM: This study aimed to determine whether there was an expression of chromogranin A, synaptophysin and Ki67 which indicated the presence of neuroendocrine neoplasms in samples that have been diagnosed as high-grade colorectal adenocarcinoma.
MATERIALS AND METHODS: A study of the expression of chromogranin A, synaptophysin and Ki67 in paraffin blocks was carried out as a result of biopsy and tissue surgery of 70 samples of colorectal tumor specimens diagnosed with colorectal adenocarcinoma. Descriptive analyses were used to assess the study results of the amount of chromogranin A, synaptophysin, and sample characteristics.
RESULTS: We discovered that eight (8) samples (11.4%) were NEN from 70 previously diagnosed samples as high-grade colorectal adenocarcinoma using immunohistochemical assay with neuroendocrine markers, namely chromogranin A and synaptophysin.
CONCLUSION: The final diagnosis obtained from 8 samples diagnosed as NEN were Neuroendocrine tumor (NET) G1, G2, and G3, respectively 1.4% and LCNEC 7.1% based on the specific neuroendocrine markers of chromogranin A, synaptophysin and Ki67.