450P Are Grade III Well-Differentiated Neuroendocrine Tumours a Unique Clinic-Pathological Entity?

Neuroendocrine neoplasms (NENs) are a rare group of malignancies with significant mortality. Recently, Grade 3 (G3) NENs have been dichotomised into well-differentiated neuroendocrine tumours (NETs) and poorly differentiated carcinomas (NECs), with seemingly different characteristics. Treatment for these groups differs, although there is not enough evidence to identify a uniform standard of care. We aim to understand whether the difference between NET and NEC G3 is clinically significant, and if so, what these are in terms of their clinical characteristics.