A novel study published in The Journal of Nuclear Medicine has revealed the promising effectiveness of peptide receptor radionuclide therapy (PRRT) in clinically controlling symptomatic metastatic insulinomas. This research is considered the largest study of its kind to date, and it shows that over 80% of patients experienced long-lasting symptom control, with nearly 60% successfully reducing their reliance on other drugs to manage the disease.
Metastatic insulinoma is a rare malignant neuroendocrine tumor characterized by inappropriate insulin secretion, leading to life-threatening hypoglycemia that is often challenging to treat. Symptoms can range from mild to severe, with some cases resulting in coma and death. While most insulinomas are benign, approximately 6% develop metastases and are classified as malignant.
In this long-term retrospective study, Friebe and colleagues evaluated the therapeutic efficacy of PRRT in improving hypoglycemia, the effect of medication changes post-PRRT, and the rates of progression-free survival and overall survival. Friebe et al. highlighted the absence of clearly defined treatment approaches for malignant metastatic insulinomas, mainly due to the rarity of the disease. The treatment strategies for this type of malignant metastatic disease are not well-established, and there is limited data available regarding the efficacy of PRRT in patients with malignant insulinomas. The study included 26 patients with malignant insulinomas who underwent a total of 106 cycles of PRRT, either using 90Y-DOTATOC or 177Lu-DOTATOC. A scoring system was employed to quantify the severity and frequency of hypoglycemic episodes, with scores compared before and after PRRT. The study also collected information on medication needed to control hypoglycemia before and after PRRT, and overall and progression-free survival rates were recorded.
According to the researchers, the results from the study demonstrated that PRRT effectively controlled hypoglycemia in 81% of the study population. Additionally, 58% of patients were able to reduce the use of other drugs to manage hypoglycemic episodes, leading to a decrease in potential drug-related side effects. Overall and progression-free survival rates were reported at 19.7 and 11.7 months, respectively.
The researchers underscored the promising potential of PRRT compared to conventional drugs in hypoglycemia control, suggesting a paradigm shift in treatment guidelines for metastatic insulinomas. The superior efficacy of PRRT, highlighted in this study, advocates for its consideration as an early-line therapy for metastatic insulinomas. The study findings not only provide hope for improved management of metastatic insulinomas but also suggest a potential shift in the recommended timing of PRRT as a therapeutic option.
Reference
Friebe L, Freitag MT, Braun M, Nicolas G, Bauman A, Bushnell D, et al. Peptide Receptor Radionuclide Therapy Is Effective for Clinical Control of Symptomatic Metastatic Insulinoma: A Long-Term Retrospective Analysis. Journal of Nuclear Medicine. 2024 Feb 1;65(2):228–35.