With immunohistochemical staining the tumour cells showed strong diffuse positivity for neuron-specific enolase (NSE), chromogranin, and synaptophysin
(Figure 5, 6, 7) and were negative for cytokeratin, TTF-1 & LCA.
One of the elements of glucagonoma diagnosis is histopathological examination including immunohistochemical staining such as chromogranin or synaptophysin
specific for neuroendocrine tumors.
Immunohistochemistry showed that Synaptophysin
and CD56 were positive in the solid tumor areas and negative in the tubulo-glandular tumor foci (Figure 3); Chromogranin was positive in rare tumor cells, CDX2 was focally positive.
The neoplastic cells were positive for synaptophysin
, chromogranin, CD56, and S-100 (Figures 3, 4) and negative for cytokeratin 8/18, A1/A3, CD3, CD20, desmin, and GFAP.
Immunohistochemistry (IHC) showed positive cytokeratin (CK) 18, vimentin, PAX2, PAX8, and focal CD10 staining [Figure 2]b, [Figure 2]c, [Figure 2]d and negative staining for CK 7, CK 20, CD56, synaptophysin
, and chromogranin A.
Further histochemical analysis revealed a Ki-67 of 80% and positivity for CD56 and synaptophysin
diagnostic of high-grade invasive neuroendocrine breast carcinoma (Figure 1).
The tumor cells of the polypoid tumors were positive for pancytokeratin, synaptophysin
, chromogranin A, CD57, protein gene protein 9.5 (PGP9.5), and Ki67 (2% of labeled cells) (Figure 3).
Immuno-histo-chemical staining shows positive immunore-activity to chromogranin A, neuron specific enolase, synaptophysin
, and CEA2,6.
It can be detected by standard microscopic analysis and immunohistochemistry staining with neuroendocrine markers such as synaptophysin
and chromogranin A.
Immunohistochemistry was positive for vimentin and synaptophysin
[Figure 2] while negative for pan-Cytokeratin (panCK), P-40, S-100, epithelial membrane antigen (EMA), chromogranin, melan-A, desmin, smooth muscle actin (SMA), neuron-specific enolase, CD99, CD56, CD20, CD45, and glial fibrillary acid protein (GFAP), thus confirming ESMC.
For this aim, three different presynaptic proteins, namely synaptophysin
(Syp), synaptotagmin 7 (Syt7) and secretogranin 2 (SG2), were selected considering their roles in different parts of the presynaptic compartment.
The analysis also showed reduced production of two proteins important for neuron-to-neuron communication at synapses: synaptophysin
and a glutamate receptor protein.