Safety of loco-regional treatments in neuroendocrine liver metastases compared to an hepato-cellular carcinoma cohort: a single-center study.

Purpose: Gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) present with neuroendocrine liver metastases (NELM) in approximately 60% of the cases. Loco-regional interventional radiology procedures are widely used in the treatment of hepatocellular carcinoma (HCC) and have been increasingly used in recent years also in the setting of NELM. We aimed to assess the safety and, as a secondary aim, the local response of trans-arterial embolization (TAE) in NELM in our consecutive cohort of GEP-NEN patients.

Materials and methods: We collected data from all consecutive patients who underwent TAE for NELM secondary to GEP-NENs at IRCCS Humanitas Research Hospital, from March 2014 to February 2024. Safety and efficacy data were retrospectively collected. Short-term procedure-related adverse events (AE) were classified according to the new Society of Interventional Radiology classification. An internal analysis was also carried out on results from a cohort of patients with compensated advanced chronic liver disease complicated by HCC and treated with TAE.

Results: A total of 45 procedures in 21 patients were consecutively performed during the study period. Mean age at diagnosis was 56.6 years (SD 12.6) and median follow-up time was 60 months (range 10-169). At the time of treatment, the disease was bilobar in 19 cases (90.4%), with multifocal metastases present in 11 cases (52.3%). Adverse events were defined immediate (within 24 h from the procedure), early (within 30 days after the procedure), and late (> 30 days after the procedure). The rate of complications was 33.3% (N = 15), mostly comprising sepsis (73.3%, N = 11) which in 2 patients was secondary to the development of a perilesional abscess, requiring extended antibiotic therapy and, in one case, percutaneous drainage. Only one case of post-procedural bleeding was reported, which required further radiological embolization. Other less common AEs were reported, including acute post-procedural hepatitis, acute heart failure, and a generalized urticarial skin rash. The median length of hospitalization per procedure was 3 days (range 1-49). Only one tumor-related death was reported during the follow-up period. Disease stabilization or partial response was achieved in 86.6% (N = 39) of the procedures. In the HCC population a lower complication rate was observed: 6.10%, 5/82 patients: 3 were represented by liver abscess, one by acute-on-chronic liver failure and one by hepatic ischemia and consequent liver decompensation with ascites. 33 patients developed partial response (33/82, 40.24%). At one-year follow-up a 82.93% recurrence rate and a 1.22% mortality rate were detected.

Conclusion: While loco-regional radiological treatments are recognized as safe and effective treatments for HCC, in the setting of NELM few data are available. In the current series TAE could represent a promising option for NELM treatment. The complication rate in NELM setting appears slightly higher than that reported both in the literature and in our own series for HCC treatment. Further studies are needed to fully assess TAE safety in NELM setting.