Current medical treatment of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (NETs) consist of a wide group of neoplasms, with different biological behaviors in terms of aggressiveness and hormone production. In the last two decades, significant progress has been observed in our understanding of their biology, diagnosis and treatment. Surgery remains to be the only curative approach, but unfortunately the diagnosis is often delayed due to the slow growth of these tumors and the difficulty in identifying the symptoms related to the tumor-released hormones. In addition to surgery, other approaches to control the disease are biological therapy consisting of somatostatin analogs and interferon (IFN), systemic chemotherapy, radioligand therapy and local therapy with chemoembolization. Several newer cytotoxic agents, including irinotecan, gemcitabine, taxanes, oxaliplatin, capecitabine and PS-341 have been studied in metastatic patients. Considering the high vascularity of these tumors, antiangiogenic agents like endostatin and thalidomide have also been evaluated in advanced NETs. Although these agents seem to have potential activity in NETs and may increase progression free survival, none of these currently available medical therapeutic options are curative. While more efficient novel strategies are to be developed, the rationale use of the current therapeutic options may improve quality of life, control the symptoms related to the hypersecretion of hormones and/or peptides, control tumor proliferation and prolong survival in patients suffering from NETs.