Role of chemotherapy in gastro-entero-pancreatic neuroendocrine tumors: the end of a story?

Gastroenteropancreatic Neuroendocrine Tumours (GEP NET) are heterogeneous and rare malignancies although their prevalence is increasing. Multiple therapeutic approaches are available to date for their management, including surgery, hormonal and immune radionucleide therapies and chemotherapy. The purpose of this review is to collect, examine, and analyze data available regarding contemporary chemotherapeutic management of GEP NET in order to determine whether or not chemotherapy still takes place in the therapeutic arsenal of GEP NET. We therefore performed a systematic search of all the English-spoken literature regarding GEP NET. Anthracyclins, 5-fluorouracil (5-FU), DTIC and streptozotocin are amongst the most commonly used chemotherapeutic agents, usually prescribed in combination. Their efficiency in reducing tumor burden is not always associated with better survival, perhaps due to severe toxicity. Chemotherapy in GEP NET is mainly devoted to poorly differentiated tumours, but also in well differentiated carcinomas either not eligible or resistant to other therapies. Chemotherapy remains therefore useful in specific cases of GEP NET management. However, a new era of antitumoral agents, such as targeted therapies, could eventually replace these old recipes in the near future.