Response, Survival, and Long-Term Toxicity After Therapy With the Radiolabeled Somatostatin Analogue [⁹⁰Y-DOTA]-TOC in Metastasized Neuroendocrine Cancers

Abstract

This study documents the long-term outcome of [(90)Y-DOTA]-TOC treatment in a large cohort. Response to [(90)Y-DOTA]-TOC is associated with longer survival. Somatostatin receptor imaging is predictive for both survival after [(90)Y-DOTA]-TOC treatment and occurrence of renal toxicity.

Peptide receptor radionuclide therapy for neuroendocrine tumours: standardized and randomized, or personalized?

“…In this large cohort of Romer et al, median survivals after 177 Lu and 90 Y-DOTA-TOC were 46 and 36 months, respectively. These results are consistent with those found in numerous other trials of PRRT [7][8][9][10][11][12][13][14][15]. In clinical practice, we frequently observe favourable responses with PRRT in patients with symptomatic, progressive disease resistant to all conventional therapy and often despite poor performance status.…”

Whither peptide receptor radionuclide therapy for neuroendocrine tumors: an Einsteinian view of the facts and myths

“…An even more relevant parameter for efficacy of any treatment, i.e., OS, indicates a survival benefit of 40-72 months from the time of first diagnosis compared to historical controls (suboptimal, albeit only available reference point) [26]. Patients are expected to live for 96.4 months after the first diagnosis if treated with 90 Y-DOTATOC [27]. Additionally, patients responding to PRRT (morphological, clinical, or biochemical) and qualified for re-treatment are expected to have a benefit of 20 months in OS after first diagnosis; using the time of first treatment as the reference point, patients showing a response were likely to live for approximately 2.8 times longer than the nonresponders [27].…”

“…The high incidence of renal toxicity, which is especially prominent for 90 Y peptides (3-9 % G4 toxicity [27,32], is less of a clinical problem after 177 Lu-octreotate (0.4 % incidence of G4 toxicity) [26]. Several postulates have been proposed to explain PRRT nephrotoxicity.…”

“…Severe, grade 3 or 4 hematological toxicity occurs in less than 15 % [26,27,37,38]. A highgrade potentially life-threatening bone marrow toxicity (myelodysplasia) is reported in up to 2 % [39][40][41].…”

“…The response rate to PRRT varies significantly depending on the location of the primary tumor. For example, an SST receptorpositive metastasized ileal NET exhibits a response rate which is much lower than SST receptor-positive metastasized pancreatic NET [26,27,29]. Given these observations, the concept of utilizing PRRT in all well to moderately differentiated gastroenteropancreatic NETs requires critical reassessment.…”