The efficacy of “rechallenge” peptide receptor radionuclide therapy (PRRT) may be inferior to that of the initial PRRT, while the safety profile remains comparable

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Introduction: Data on efficacy and adverse events of re-challenge PRRT (re-PRRT) for patients with gastrointestinal neuroendocrine tumours (GI-NETs) are limited.

Aim(s): We compared initial PRRT (i-PRRT) and re-PRRT, focusing on potential prognosticators of progression-free survival (PFS).

Materials and methods: PFS was evaluated in 19 patients with GI-NET after i-PRRT and re-PRRT. Baseline blood count and various laboratory parameters (CRP, LDH, creatinine, GFR, bilirubin, gamma-GT, ALT, and AP), as well as somatostatin receptor directed PET metrics (SUVmean, SUVmax, and SSTR-positive tumour volume) were determined and compared between i- and re-PRRT. A Cox regression analysis was conducted to identify prognostic factors for PFS. Adverse events were classified in accordance with CTCAE v5.0.

Conference:

Presenting Author: Heinrich M

Authors: Heinrich M, Lutz F, Alwers S, Däubler C, Buck A,

Keywords: gastrointestinal neuroendocrine tumour, somatostatin receptor directed PET, laboratory parameters, Progression-free survival,