While NSE is a highly specific marker for neurons and neuroendocrine cells, it does have some limitations: 1. Cross-reactivity: Although rare, there can be cross-reactivity with other non-neuronal tissues, potentially leading to false-positive results. 2. Limited Sensitivity: In some cases, particularly in poorly differentiated tumors, NSE expression may be low or absent, limiting its utility as a diagnostic marker. 3. Variability in Expression: NSE expression can vary between different types of neuroendocrine tumors, potentially complicating the interpretation of results.
