Peptide Receptor Radionuclide Therapy with 177Lu-DOTATATE in Advanced Neuroendocrine Tumours (NETs) in a Limited Resource Environment

Abstract

BackgroundWe decided to evaluate the clinical efficacy and safety of peptide receptor radionuclide therapy (PRRT) with 177-DOTATATE in patients with neuroendocrine tumors (NETs).MethodsSixteen patients with pathologically verified NETs including eight females and eight males were enrolled in this study. Before PRRT for evaluation of somatostatin receptor expressing, the patients underwent 68Ga-DOTATATE PET-CT or 99mTc-octreotide scintigraphy. The treatment response was assessed according to the response evaluation criteria in solid tumors (RECIST) which was classified into complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). In addition, for evaluation of toxicity, monthly blood analysis was performed including hematology, renal function (creatinine), liver status. The Eastern Cooperative Oncology Group (ECOG) status performance was applied for estimating the patients’ general condition including 0 (fully active) to 5 (dead). In addition, overall survival (OS) was calculated as the time interval between start of PRRT to death from any reason.ResultsSixteen patients including eight females and eight males with median age of 60.5 years old with range of 24-74 were enrolled in this study. The patients underwent PRRT with median cycles of 3.5 with range of 1-7 and median dose of 20.35 with range of 7.4 to 49.95 GBq. At the end of data collection, 11/16 patients had PR, 2/16 showed CR, 1/16 showed SD and 2/16 showed PD according to the RECIST. 3 patients were expired during and after the PRRT period time. Before PRRT, the medians of ECOG and KPS were 1.5 and 75 which after treatment were, significantly, improved to 1 and 80, respectively (p<0.05). According to the Kaplan-Meier test, the median of OS was obtained 23 months (95%CI:7.90-38.09). According to the CTCAE, 3 patients showed grade I and 3 other showed grade II leucopenia. Furthermore, 3 and 7 patients had grade II and grade I anemia, respectively.ConclusionIt can be concluded that, since PRRT with 177Lu-DOTATATE in NETs has favorable response rate, few adverse effects and leads to improvement in QOL, it can be used as an effective therapeutic option specially in nonoperative, metastatic and progressive NETs.