Lutetium-177 Dotatate Therapy, Revolutionizing the Way Somatostatin Receptor-Positive Neuroendocrine Tumors are Treated

Objectives: The incidence of neuroendocrine tumors (NETs) has increased in prevalence by 6-folds over the past 4 decades, becoming much more common than ever before. Furthermore, there is an average of a 5-7 year delay in the diagnosis, resulting in advanced metastatic cases at the time of diagnosis in over 50% of patients with NETs. Since the approval of Lutetium-177 (Lu-177) Dotatate (Lutathera) by the FDA in January 2018 for NETs, good response to therapy has been widely reported by NM facilities offering such therapy. The purpose of this study is to evaluate and provide education on the logistics surrounding Lutathera therapy, with regards to patient preparation, radiopharmaceutical administration, and radiation safety issues.

Methods: The patient preparation and protocols that are already set in place by hospitals for Lutathera therapy were reviewed. Nuclear Medicine physicians and technologists that have been working with Lu-177 Dotatate therapy were interviewed about the current process and potential issues.

Results: Given the potential of renal toxicity, the standard of care protocol for the delivery of Lutathera includes Amino Acid pretreatment to protect the kidneys, as well as antiemetics to minimize nausea/vomiting caused by the Amino Acid. The Lutathera dose is typically given over a 30-minute infusion; however, the whole therapy protocol, including the administration of the non-radiopharmaceutical (antiemetic and Amino Acids), is a 4-6 hour process. Furthermore, while many facilities allow NM technologists privileges to administer non-radiopharmaceuticals within the department, some facilities limit such privilege to a nurse to start treatment and monitor the patient’s vital signs. Per the NRC, Lutetium-177 (T1/2 = 6.7 days) may contain Lu-177m as a contaminant with a T1/2 of 161 days, which contributes approximately 0.02 percent of the total amount of Lu-177. Such a contaminant can not be decayed in storage under rule 10 CFR 35.92, “Decay-in-storage,” because its half-life is greater than 120 days. This issue is requiring NM centers to contract with an outside company who will take care of the waste disposal and assure that it is properly being handled. Furthermore, most NM facilities are functioning with only one bathroom for radioactive patients. Any contamination from Lutathera patients may lead to, at best, labor-intensive decontamination efforts, or at worst, closure of a bathroom for weeks or even months in the case of Lu -177m.

Conclusions: While Lutathera has helped with the treatment of metastatic NETs, some medical facilities have opted against its use or are not ready for the introduction of theranostics, as they do not have the means to deliver this service, whether that be sufficient staffing, disposal procedures, infrastructure, or a combination of all. Future NM centers should include a theranostic designated area and team capable of a safe and effective delivery of current and upcoming radionuclide therapeutic options.