TY - JOUR A1 - Werner, Rudolf A. A1 - Beykan, Seval A1 - Higuchi, Takahiro A1 - Lückerath, Katharina A1 - Weich, Alexander A1 - Scheurlen, Michael A1 - Bluemel, Christina A1 - Herrmann, Ken A1 - Buck, Andreas K. A1 - Lassmann, Michael A1 - Lapa, Constantin A1 - Hänscheid, Heribert T1 - The impact of \(^{177}\)Lu-octreotide therapy on \(^{99m}\)Tc-MAG3 clearance is not predictive for late nephropathy JF - Oncotarget N2 - Peptide Receptor Radionuclide Therapy (PRRT) for the treatment of neuroendocrine tumors may lead to kidney deterioration. This study aimed to evaluate the suitability of \(^{99m}\)Tc-mercaptoacetyltriglycine (\(^{99m}\)Tc-MAG3) clearance for the early detection of PRRT-induced changes on tubular extraction (TE). TE rate (TER) was measured prior to 128 PRRT cycles (7.6±0.4 GBq \(^{177}\)Lu-octreotate/octreotide each) in 32 patients. TER reduction during PRRT was corrected for age-related decrease and analyzed for the potential to predict loss of glomerular filtration (GF). The GF rate (GFR) as measure for renal function was derived from serum creatinine. The mean TER was 234 ± 53 ml/min/1.73 m² before PRRT (baseline) and 221 ± 45 ml/min/1.73 m² after a median follow-up of 370 days. The age-corrected decrease (mean: -3%, range: -27% to +19%) did not reach significance (p=0.09) but significantly correlated with the baseline TER (Spearman p=-0.62, p<0.001). Patients with low baseline TER showed an improved TER after PRRT, high decreases were only observed in individuals with high baseline TER. Pre-therapeutic TER data were inferior to plasma creatinine-derived GFR estimates in predicting late nephropathy. TER assessed by \(^{99m}\)Tc-MAG3­clearance prior to and during PRRT is not suitable as early predictor of renal injury and an increased risk for late nephropathy. KW - renal scintigraphy KW - neuroendocrine tumor KW - 177Lu KW - MAG3 KW - PRRT Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177318 VL - 7 IS - 27 ER - TY - JOUR A1 - Lapa, Constantin A1 - Werner, Rudolf A. A1 - Bluemel, Christina A1 - Lueckerath, Katharina A1 - Muegge, Dirk O. A1 - Strate, Alexander A1 - Haenscheid, Heribert A1 - Schirbel, Andreas A1 - Allen-Auerbach, Martin S. A1 - Bundschuh, Ralph A. A1 - Buck, Andreas K. A1 - Herrmann, Ken T1 - Prediction of clinically relevant hyperkalemia in patients treated with peptide receptor radionuclide therapy JF - EJNMMI Research N2 - Background Peptide receptor radionuclide therapy (PRRT) is applied in patients with advanced neuroendocrine tumors. Co-infused amino acids (AA) should prevent nephrotoxicity. The aims of this study were to correlate the incidence of AA-induced hyperkalemia (HK) (≥5.0 mmol/l) and to identify predictors of AA-induced severe HK (>6.0). Methods In 38 patients, standard activity of \(^{177}Lu\)-labelled somatostatin analogs was administered. Pre-therapeutic kidney function was assessed by renal scintigraphy and laboratory tests. For kidney protection, AA was co-infused. Biochemical parameters (potassium, glomerular filtration rate, creatinine, blood urea nitrogen (BUN), sodium, phosphate, chloride, and lactate dehydrogenase (LDH)) were obtained prior to 4 and 24 h after the AA infusion. Incidence of HK (≥5.0) was correlated with pre-therapeutic kidney function and serum parameters. Formulas for the prediction of severe hyperkalemia (>6.0) were computed and prospectively validated. Results At 4 h, HK (≥5.0) was present in 94.7% with severe HK (>6.0) in 36.1%. Values normalized after 24 h in 84.2%. Pre-therapeutic kidney function did not correlate with the incidence of severe HK. Increases in K+ were significantly correlated with decreases in phosphate (r = −0.444, p < 0.005) and increases in BUN (r = 0.313, p = 0.056). A baseline BUN of >28 mg/dl had a sensitivity of 84.6% and a specificity of 60.0% (AUC = 0.75) in predicting severe HK of >6.0 (phosphate, AUC = 0.37). Computing of five standard serum parameters (potassium, BUN, sodium, phosphate, LDH) resulted in a sensitivity of 88.9% and a specificity of 79.3% for the prediction of severe HK >6.0 (accuracy = 81.6%). Conclusions A combination of serum parameters predicted prospectively the occurrence of relevant HK with an accuracy of 81.6% underlining its potential utility for identifying ‘high-risk’ patients prone to PRRT. KW - amino acids KW - kidney function KW - hyperkalemia KW - PRRT KW - NET KW - MAG3 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124963 VL - 4 IS - 74 ER - TY - JOUR A1 - Werner, Rudolf A. A1 - Lapa, Constantin A1 - Bluemel, Christina A1 - Lückerath, Katharina A1 - Schirbel, Andreas A1 - Strate, Alexander A1 - Buck, Andreas K. A1 - Herrmann, Ken T1 - Influence of the amount of co-infused amino acids on post-therapeutic potassium levels in peptide receptor radionuclide therapy N2 - Background Peptide receptor radionuclide therapy (PRRT) is routinely used for advanced or metastasized neuroendocrine tumours (NET). To prevent nephrotoxicity, positively charged amino acids (AA) are co-infused. The aim of this study was to correlate the risk for therapy-related hyperkalaemia with the total amount of AA infused. Methods Twenty-two patients undergoing PRRT with standard activities of 177Lu-DOTATATE/-TOC were monitored during two following treatment cycles with co-infusion of 75 and 50 g of AA (L-arginine and L-lysine), respectively. Mean serum levels of potassium and other parameters (glomerular filtration rate [GFR], creatinine, blood urea nitrogen [BUN], phosphate, chloride, lactate dehydrogenase) prior to, 4 h and 24 h after AA infusion were compared. Results Self-limiting hyperkalaemia (>5.0 mmol/l) resolving after 24 h occurred in 91% (20/22) of patients in both protocols. Potassium levels, BUN, creatinine, GFR, phosphate, chloride and LDH showed a similar range at 4 h after co-infusion of 75 or 50 g of AA, respectively (p > 0.05). Only GFR and creatinine levels at 24 h varied significantly between the two co-infusion protocols (p < 0.05). Conclusions Hyperkalaemia is a frequent side effect of AA infusion in PRRT. Varying the dose of co-infused amino acids did not impact on the incidence and severity of hyperkalaemia. KW - NET KW - PRRT KW - Hyperkalaemia KW - Arginine KW - Lysine Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-110617 ER -