Localization and Tumor Growth Inhibition of I-131-Labeled Monoclonal Antibody ERIC1 in a Subcutaneous Xenograft Model of Small Cell Lung Cancer in SCID Mice.

This study evaluates the efficacy of [I]I-ERIC1 in targeting and inhibiting the growth of SCLC tumors in mice, focusing on tumor accumulation and regression and potential side effects. NCAM-positive NCI-H69 SCLC cells were implanted in CB 17 SCID mice, and [I]I-ERIC1 biokinetics were measured in organs and tissues at four post-injection time points (24, 72, 96, and 120 h). The experimental series compared tumor growth, survival, and changes in blood counts among three treatment groups (1, 2, or 3 MBq) and a control group, with treatments initiated either two or five days post implantation.

Synthesis and evaluation of radioiodinated estrogens for diagnosis and therapy of male urogenital tumours.

The preparation of 24 estrogens, their estrogen receptor (ER) affinity and studies of radioiodinated estrogen binding to ER-positive male bladder tumor cells (HTB9) are described. The estrogens with the highest affinity were selected using fluorescence anisotropy assays. A 2,2,2-trifluoroethyl group at the 11β-position caused particularly promising affinity.

Characterization of SnO2-based (68)Ge/ (68)Ga generators and (68)Ga-DOTATATE preparations: radionuclide purity, radiochemical yield and long-term constancy.

Background: With the increasing utilization of (68)Ge-(68)Ga radionuclide generators, (68)Ga labelled peptides like DOTATATE are receiving more attention in nuclear medicine. On the one hand, the long half-life of the parent nuclide (68)Ge is an enormous advantage for routine applications, but the question of the long-term stability of the (68)Ge breakthrough arises, which up to now has scarcely been investigated.

Method: A sum of 123 eluates from four different (68)Ge-(68)Ga generators (iThemba Labs, Faure, South Africa) and 115 samples of the prepared radiopharmaceutical (68)Ga-DOTATATE were measured first with a dose calibrator and again after decay of the eluted (68)Ga via gamma-ray spectrometry.

Cellular response on Auger- and Beta-emitting nuclides: human embryonic stem cells (hESC) vs. keratinocytes.

Purpose: We studied the response of human embryonic stem cells (hESC) to the β-emitter (131)I, which affects the entire cell and to the Auger electron emitter (125)I-deoxyuridine ((125)I-dU), primarily affecting the deoxyribonuleic acid (DNA). The effects were also studied in keratinocytes as a prototype for somatic cells.

Methods: HESC (H1) and human keratinocytes (HaCaT, human) were exposed to (125)I-dU (5 × 10(-5) - 5 MBq/ml) and (131)I-iodide (5 × 10(-5) - 12.

Development of hypothyroidism during long-term follow-up of patients with toxic nodular goitre after radioiodine therapy.

Objective: To investigate the cure rate and incidence of hypothyroidism of radioiodine treatment with a calculated dose regimen and an intended thyroid dose of 150 Gy in patients with toxic nodular goitre during long-term follow-up.

Patients: A total of 265 consecutive patients with toxic nodular goitre were treated between March 2003 and August 2004 at our institute and followed up for a maximum of 8 years. Preliminary radioiodine testing with volumetric measurement of the thyroid by ultrasound as well as individual thyroidal radioiodine uptake and half-life measurements were performed before radioiodine therapy.

Exhalation of ¹³¹I after radioiodine therapy: measurements in exhaled air.

Purpose: A considerable amount of radioiodine is exhaled after radioiodine therapy leading to unwanted radiation exposure through inhalation. This study focused on the concentration of radioactivity exhaled and its chemical nature.

Methods: Air exhaled by 47 patients receiving (131)I-iodine for different thyroid diseases (toxic goitre n = 26, Graves' disease n = 13, thyroid cancer n = 8) was investigated with a portable constant air-flow sampler.

Dosimetry for 131I-MIBG therapies in metastatic neuroblastoma, phaeochromocytoma and paraganglioma.

Purpose: Radiation dosimetry is a basic requirement for targeted radionuclide therapies (TRT) which have become of increasing interest in nuclear medicine. Despite the significant role of the radiopharmaceutical (131)I-metaiodobenzylguanidine (MIBG) for the treatment of metastatic neuroblastoma, phaeochromocytoma and paraganglioma details for a reliable dosimetry are still sparse. This work presents our procedures, the dosimetric data and experiences with TRT using (131)I-MIBG.

Radioiodine therapy of benign thyroid disorders: what are the effective thyroidal half-life and uptake of 131I?

Aim: The use of radioiodine therapy is common in the treatment of benign thyroid disease. Council directive Euratom 97/43 requires that for all medical exposure of individuals for radiotherapeutic purposes exposures of target volumes should be individually planned. There are several strategies to accomplish this aim for radioiodine therapy including individual radioiodine uptake measurement and using either individual or mean effective radioiodine uptake and half-life.