G3 neuroendocrine carcinoma
High-grade neuroendocrine neoplasm with Ki-67 proliferation index >20% and aggressive clinical behavior.
Full Definition
G3 neuroendocrine carcinoma represents the most aggressive category of neuroendocrine neoplasms according to WHO classification, characterized by high proliferative activity with Ki-67 index exceeding 20%. These tumors typically present with widespread metastatic disease and poor prognosis. Treatment approaches often include platinum-based chemotherapy regimens similar to those used for small cell lung cancer. The G3 category has been further subdivided into well-differentiated G3 NETs and poorly differentiated neuroendocrine carcinomas based on morphological features.
Usage
Usage note: Specify morphological differentiation when using G3 classification.
In Context
- "The Ki-67 index of 45% confirmed the diagnosis of G3 neuroendocrine carcinoma." — Pathology report
- "Given the G3 neuroendocrine carcinoma diagnosis, platinum-based chemotherapy was initiated." — Treatment plan