Outcomes After Transarterial Embolization of Neuroendocrine Tumor Liver Metastases Using Spherical Particles of Different Sizes

Abstract

Purpose: To evaluate initial response and overall survival (OS) of neuroendocrine tumor (NET) liver metastases initially treated with transarterial embolization (TAE) using spherical particles of different sizes. Methods: A single-institution retrospective review was performed of 160 patients with NET liver metastases initially treated with TAE using < 100 μm (n=77) or only ≥ 100 μm (n=83) spherical particles. For each patient, we evaluated: initial response by mRECIST, time to progression, overall survival, complications, primary site, tumor grade and degree of differentiation, volume of liver disease, extrahepatic disease, NET-related symptoms, comorbidities, Child Pugh score, performance status, lobar versus selective embolization, and arteriovenous shunting. Results: Initial response was higher for TAE using particles <100 μm versus TAE using only particles ≥100 μm (64% vs 42%, p=0.007). Multivariate logistic regression showed that use of * Corresponding author. Conflict of interest: FEB is a co-founder of Claripacs, LLC. He received research funding (investigator-initiated) and support for research meetings from Guerbet. He received research support (investigator-initiated) from GE. He received research supplies (investigator-initiated) from Bayer. He received a research grant and speaker fees from Society of Interventional Oncology, which were sponsored by Guerbet. He is an investor in Labdoor, Qventus, CloudMedx, and Notable Labs. Compliance with ethical standards Ethical approval: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this type of study formal consent is not required. This HIPAA-compliant retrospective study was approved by the IRB. Informed consent: For this type of study informed consent is not required. This study has obtained IRB approval from Memorial Sloan Kettering Cancer Center and the need for informed consent was waived. Consent for publication: For this type of study consent for publication is not required.

The Role of Interventional Radiology for the Treatment of Hepatic Metastases from Neuroendocrine Tumor: An Updated Review

“…PVA was used to obtain better results because of a more distal embolization; however, these authors did not perform a comparison for tolerance, tumor response, or overall survival (OS) with gelatin sponge [ 29 ]. In a retrospective study including 160 patients with NELM treated with TAE, Zener et al compared outcomes of 83 patients treated with particles <100 μm to those of 77 patients treated with particles >100 μm and found a better initial tumor response rate for patients treated with <100 μm particles but no differences in the OS and complication rate [ 30 ].…”

“…In general, perprocedure tolerance of patients is low, with pain occurring during arterial occlusion either with TAE or TACE. To overcome this serious limitation, general anesthesia is usually performed [ 30 , 34 , 48 ]. Intra-arterial injection of lidocaine is another option to decrease the need for antalgic drugs and decrease hospital stay length [ 49 , 50 ].…”

“…No studies have compared the occurrence rates between drugs. Urinary infections, pulmonary embolism, and alteration of mental status after procedures were reported and seem to be associated with the post-procedural hospital stay length and at a lesser degree with technical parameters [ 30 , 47 , 52 ]. One patient developing a syndrome of inappropriate secretion of antidiuretic hormone following TAE with hyponatremia and several dermatologic complications has been reported [ 67 , 68 ].…”

“…Approximately 50% of patients with pre-existing biological abnormalities have normalization or decrease of these abnormalities [ 32 , 48 , 62 ]. The mean duration of these biological improvements ranges between 11 and 20 months, but repeat TAE or TACE may result in a longer duration [ 23 , 30 , 37 , 63 ].…”

Embolotherapy for Hepatic Oncology: Current Perspectives and Future Directions

“…113,114 A retrospective review examined whether using different size bland microspheres affected outcomes in 160 patients with well to moderately differentiated NET liver metastases. 115 The hypothesis was whether increased occlusion of end arterioles and subsequent ischemia would lead to improved OS. Higher objective response rates in the smaller particle group (<100 μm) compared with the larger particle group (!100 μm), 64 versus 42% (p ¼ 0.007), respectively, did not translate into prolonged OS.…”