Capecitabine plus temozolomide in well or moderately differentiated primary atypical neuroendocrine tumors: a single centre experience of two cases.

INTRODUCTION: Neuroendocrine neoplasms (NENs) are a rare and heterogeneous group of tumors, with a variety of primary origins and variable aggressiveness. NENs with an atypical primary origin, such as breast and retroperitoneal NENs, are extremely rare. As a consequence, an established diagnostic and therapeutic strategy in this particular subgroup is lacking. The combination of capecitabineandtemozolomide, called CAPTEM regimen, has produced promising response rates in patients with grade1 or 2neuroendocrine tumors of multiple origins.

CASE PRESENTATION: The first is a case of a 68-year-old woman with a metastatic primary breast neuroendocrine tumor, treated with cisplatin plus etoposide as first line, followed by CAV scheme (cyclophosphamide, doxorubicin and vincristine), and subsequently treated, in third line, with the CAPTEM regimen, obtaining radiological response and good tolerance. The second is the case of a 66-year-old woman affected by a metastatic primitive retroperitoneal NET G2. The patient progressed after a somatostatin analogue-based first line, whereas the CAPTEM regimen led to a partial and durable response with a favourable safety profile.

CONCLUSIONS: CAPTEM chemotherapy has shown to be an active and safe therapeutic option in advanced, metastatic G1/2 atypical primary NENs.