Hepatic artery embolization in advanced neuroendocrine tumors: Efficacy and long-term outcomes

Abstract

Introduction: Transarterial embolization (TAE) and transarterial chemoembolization (TACE) are established treatments for symptom control in patients with advanced neuroendocrine tumors (NETs) with significant hepatic tumor burden.

Aim: To assess efficacy, toxicity and survival parameters in NET patients undergoing TAE and TACE.

Materials and methods: A retrospective analysis was carried out of 50 patients with NETs, who underwent a total of 67 embolization procedures in a period of 9 years. All patients had symptomatic and/or radiological progression, despite previous treatments.

Results: Symptomatic improvement was observed in 75% of patients who underwent TAE and 57% of patients who had TACE (P = 0.36). Radiological response was observed following 73% of embolization treatments delivered and specifically in 82% of all TAE and 62% of all TACE procedures (P = 0.46). Plasma Chromogranin A (CgA) levels were reduced in 65% of the patients following embolization. Patients with increasing serum CgA levels after treatment had reduced median overall survival (OS) and progression-free survival (PFS) (P = 0.0001). Patients on somatostatin analogs (SSAs) at the time of treatment had improved OS (P = 0.013), but not PFS (P = 0.216). Overall, the differences in OS (P = 0.21) and PFS (P = 0.19) between one mode of treatment over the other were not found to be statistically significant. One- and 5-year OS were 65% and 41% for TACE and 90% and 57% for TAE, respectively. The commonest complication was postembolization syndrome and mortality was 4%. Overall, the complication (P = 0.18) and mortality rates (P = 0.22) were not significantly different between TAE and TACE.

Conclusions: TAE/TACE are beneficial treatments for control of symptoms as well as tumor growth, with acceptable morbidity and mortality rates. No significant efficacy and survival differences were shown between TAE and TACE. Posttreatment CgA levels and the concurrent use of SSAs were independently associated with survival.

Keywords: 5-HIAA; Chromogranin; TACE; TAE; embolization; midgut; neuroendocrine; pancreatic islet; survival.