IMMUNOHISTOCHEMISTRY, INSM-1

What this test checks

Detects INSM-1 (Insulinoma-associated protein 1), a sensitive marker for neuroendocrine differentiation in tumours. Used to confirm neuroendocrine tumours, including small cell carcinoma.

Why do people get this test?

INSM-1 is a highly sensitive neuroendocrine marker that can detect neuroendocrine differentiation even in cases where chromogranin and synaptophysin are weak or negative — improving diagnostic accuracy.

When you should consider this test

• When a tumour is suspected to be a neuroendocrine tumour but other markers are equivocal
• When classifying poorly differentiated neuroendocrine carcinomas
• As a supplementary neuroendocrine marker

How to prepare

No preparation needed — performed on biopsy or surgical tissue.