Temozolomide and capecitabine regimen as first-line treatment in advanced gastroenteropancreatic neuroendocrine tumors at a Latin American reference center

Abstract

BACKGROUND

Numerous studies have indicated that the temozolomide and capecitabine regimen (TEMCAP) exhibits a certain level of efficacy in treating advanced, well-differentiated gastroenteropancreatic neuroendocrine tumors (GEP-NET). However, published data from Peru are limited. We hypothesize that this regimen could be a viable therapeutic option for advanced GEP-NET in the Peruvian population.

AIM

To evaluate overall survival (OS) in patients diagnosed with advanced GEP-NET treated with TEMCAP at the Instituto Nacional de Enfermedades Neoplásicas (INEN) in Lima-Perú.

METHODS

A retrospective review was conducted to identify patients with GEP-NEN treated with the TEMCAP regimen between 2011 and 2021 at the INEN. A total of thirty-eight patients were included in the final analysis: Thirty-five received TEMCAP as a first-line treatment, and three as a second-line treatment. The primary objective was to evaluate OS. The efficacy and safety of TEMCAP were assessed until the occurrence of unacceptable toxicity or disease progression. Survival outcomes were estimated using the Kaplan-Meier method.

RESULTS

The median age of the patients was 52 years (range 24-77 years), and 53.3% were female. The most common symptoms at diagnosis were abdominal pain in 31 patients (81.6%). Primary tumors included 12 in the rectum (31.6%), 11 in the pancreas (28.9%), 3 in the ileum (7.9%), 2 in the mesentery (5.3%), 2 in the small intestine (5.3%), 1 in the appendix (2.6%), 1 in the stomach (2.6%) and 6 cases of liver metastasis of unknown primary (15.8%). Five were neuroendocrine tumors (NET) G1 (13.2%), 33 were NET G2 (86.8%), five had Ki67 < 3% (13.2%), and 33 had Ki67 between 3% and 20% (86.8%). TEMCAP was administered to 35 (92.1%) patients as first-line treatment. OS at 12, 36, and 60 months was estimated in 80%, 66%, and 42%, respectively, with a median OS of 49 months.

CONCLUSION

TEMCAP therapy is a viable first-line option regarding efficacy and tolerability in areas where standard therapy is inaccessible.

Keywords: Well-differentiated; Gastroenteropancreatic neuroendocrine tumors; Capecitabine; Temozolomide; Retrospective study; Treatment; Chemotherapy

Core Tip: In this study, patients diagnosed with advanced gastroenteropancreatic neuroendocrine tumors who were treated with the temozolomide and capecitabine regimen exhibited a median overall survival of 49 months, with 42% surviving at 60 months. The regimen was well-tolerated, and most patients experienced stable disease. These findings suggest that this treatment could be viable in settings where standard therapies are unavailable or inaccessible, although further prospective studies are needed for confirmation.