Renal Function Studies Using 99mTc-MAG3: Pharmacokinetics and Slope Clearance Determination

Jang

Labelled Comp Radiopharmac

2004

Section: M Tc(i) Tricarbonyl Cysteine As a Renal Function Diagnosticmentioning

confidence: 83%

Section: Design Of An Improved 99mmentioning

confidence: 99%

Synthesis and biological characterization of ^99mTc(I) tricarbonyl cysteine complex, a potential diagnostic for assessment of renal function

Jang

Labelled Comp Radiopharmac

2004

“…In accordance with clinical standards, renal scintigraphy was also performed before the therapy, using a previously described procedure (10,11), to rule out obstructive disease and to evaluate kidney function. In cases of obstructive disease, the patients were referred to the local urologist to reduce the obstruction as much as possible.…”

Section: Patient Preparationmentioning

confidence: 99%

Response and Tolerability of a Single Dose of¹⁷⁷Lu-PSMA-617 in Patients with Metastatic Castration-Resistant Prostate Cancer: A Multicenter Retrospective Analysis

et al. 2016

Radiolabeled prostate-specific membrane antigen (PSMA) ligands represent a true theranostic concept for diagnosis and therapy in patients with relapsed or metastatic prostate cancer. The aim of this study was to evaluate the response to and tolerability of a single dose of 177 Lu-PSMA-617 in a large cohort of patients with metastatic castration-resistant prostate cancer (mCRPC). Methods: The data of 82 consecutive patients (median age, 73 y; range, 43-87 y) with mCRPC who received a single dose of 177 Lu-PSMA-617 (mean, 5.9 ± 0.5 GBq) were retrospectively analyzed. Data were collected at baseline and 8 wk after therapy. 68 Ga-PSMA-11 PET/CT was performed on all patients to verify sufficient PSMA expression. Bone, lymph node, liver, and lung metastases were present in 99%, 65%, 17%, and 11% of the patients, respectively. Tolerability and response were evaluated using hematologic parameters, renal scintigraphy, clinical data, and the prostate-specific antigen (PSA) level at baseline and 8 wk after therapy application. Results: Six patients died, and 2 patients dropped out because they were not willing to continue therapy and follow-up. The complete dataset of 74 patients was available for analysis. Forty-seven patients (64%) showed a PSA decline, including 23 (31%) with a decline by more than 50%. Thirty-five patients (47%) had stable disease: the change in their PSA level ranged from less than a 50% decline to less than a 25% rise. Seventeen patients (23%) had progressive disease: their PSA level rose by more than 25%. There were no significant changes in hemoglobin, white blood cells, creatinine, or tubular extraction rates indicative of toxicity. There was a significant but mild decrease in platelets, but the median value was still within the reference range. Conclusion: This retrospective multicenter analysis suggests that radioligand therapy with 177 Lu-PSMA-617 is safe and well tolerated and has a considerable effect on PSA level. Therefore, it offers an additional therapeutic option for patients with mCRPC. These data may justify further prospective randomized studies to evaluate and prove the clinical benefit in terms of survival and quality of life.

“…The new algorithms were calculated using the basic data available to us, which have also been applied to calculate earlier algorithms, valid only for adults (Bubeck et al 1990b;Bubeck 1991). At that time, the reference clearance values were determined under steadystate conditions in the course of 40 rain immediately after the blood sampling during slope.…”

Section: Methodsmentioning

confidence: 99%

“…Our efforts to modify algorithms for adults by taking into account the individual body dimensions (Bubeck et al 1990b) so that they become both more precise and applicable to children were based on the following consideration. The specific plasma concentration (c/ID= concentration related to the injected dose), which is measured at a specific time after single-shot application of a clearance agent, is not only dependent on the individual renal function but also on the actual volume of distribution and the plasma volume, respectively, according to the patient's body dimensions.…”

Section: Introductionmentioning

confidence: 99%

A new principle to normalize plasma concentrations allowing single-sample clearance determinations in both children and adults

Bubeck

Piepenburg²,

Grethe

et al. 1992

Eur J Nucl Med

A sufficiently accurate quantification of renal function requiring only one plasma sample without an additional gamma-camera study has, until now, only been possible in adults. A new principle will be presented here allowing the universal application of known algorithms, regardless of the clearance substance used, by normalizing the plasma concentrations with respect to the individual body dimensions of the patients--for infants as well as for adults. In this respect, algorithms are developed for clearance determinations using technetium-99m mercaptoacetyltriglycine (99mTc-MAG3), which are based on steady-state studies as the reference. They allow the calculation of quantitative clearance values in infants, requiring only one blood sampling at any time between the 25th and the 40th min postinjection. The comparison with a combined camera/two-plasma-sample technique performed in 46 children aged between 9 days and 14 years (mean 6.05 years) resulted in a standard error of 8.5% from the line of identity (r = 0.94). Moreover, this procedure also increases the accuracy of results in adults.