Radioembolization Versus Bland Embolization for Hepatic Metastases from Small Intestinal Neuroendocrine Tumors: Short‐Term Results of a Randomized Clinical Trial

Abstract

BackgroundRadioembolization (RE) with intra-arterial administration of 90Y microspheres is a promising technique for the treatment of liver metastases from small intestinal neuroendocrine tumors (SI-NET) not amenable to surgery or local ablation. However, studies comparing RE to other loco-regional therapies are lacking. The aim of this randomized study was to compare the therapeutic response and safety after RE and bland hepatic arterial embolization (HAE), and to investigate early therapy-induced changes with diffusion-weighted MRI (DWI-MRI).MethodsEleven patients were included in a prospective randomized controlled pilot study, six assigned to RE and five to HAE. Response according to RECIST 1.1 using MRI or CT at 3 and 6 months post-treatment was recorded as well as changes in DWI-MRI parameters after 1 month. Data on biochemical tumor response, toxicity, and side effects were also collected.ResultsThree months after treatment, all patients in the HAE group showed partial response according to RECIST while none in the RE group did (p = 0.0022). After 6 months, the response rates were 4/5 (80%) and 2/6 (33%) in the HAE and RE groups, respectively (NS). DWI-MRI metrics could not predict RECIST response, but lower pretreatment ADC(120–800) and larger ADC(0–800) increase at 1 month were related to larger decrease in tumor diameter when all tumors were counted.ConclusionHAE resulted in significantly higher RECIST response after 3 months, but no difference compared to RE remained after 6 months. These preliminary findings indicate that HAE remains a safe option for the treatment of liver metastases from SI-NET, and further studies are needed to establish the role of RE and the predictive value of MR-DWI.Electronic supplementary materialThe online version of this article (10.1007/s00268-017-4324-9) contains supplementary material, which is available to authorized users.

Comparison of methods for estimation of the intravoxel incoherent motion (IVIM) diffusion coefficient (D) and perfusion fraction (f)

“…MR imaging data from patients with liver metastases from small-intestine NET was obtained from a previously published randomized clinical trial of embolization methods [25]. Patients were randomly assigned to either hepatic artery embolization or radioembolization treatment and were examined with MRI before and one and 3 months after treatment.…”

“…Among the 11 patients in the previous study, one failed to undergo the MR examination due to cardiac pacemaker, and one was examined with a different MR protocol, resulting in nine patients for analysis. For detailed descriptions of inclusion criteria and treatments, the reader is referred to the previous paper [25]. The MR examinations included in the study we report here were those performed before (baseline) and 3 months after treatment.…”

Studying Prognosis and Treatment in Patients with Neuroendocrine Neoplasia

“…investigated response and toxicity after TAE and SIRT in 11 patients with a SI-NET. 61 An equal biochemical response and radiological response was shown in patients with metastatic NET. However, the small sample size is a major limitation of this study.…”

“…In the cohort 192 patients (48%) were male and 208 patients (52%) were female. Median age was 63 years (IQR [55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71]. A total of 244 patients (61%) were referred within 3 months of diagnosis.…”

“…60 Loco-regional recurrence is seen in up to 60% of the patients, often within two years after diagnosis. 61,62 Overall survival ranges from 30 to 60%. 63 The presence of nodal disease and primary tumour size are identified as predictors for a worse survival.…”