Quantitative assessment of radioactivity losses in the administration of therapeutic doses of [177Lu]Lu-DOTA-TATE and [90Y]Y-DOTA-TATE.

Background: Therapeutic radiopharmaceuticals [¹⁷⁷Lu]Lu-DOTA-TATE and [⁹⁰Y]Y-DOTA-TATE are used in peptide receptor radionuclide therapy (PRRT) of neuroendocrine tumors. One of the factors determining the efficacy of such therapy is administering the radiopharmaceutical dose to the patients in a way consistent with treatment planning. This paper evaluates the loss of [¹⁷⁷Lu]Lu-DOTA-TATE and [⁹⁰Y]Y-DOTA-TATE and their mixed doses during the administration to the patient either by direct infusion or by gravity method.

Identification of the Optimal Cut-Off Value of PSA for Assessing Severity of Disease in [Ga]Ga-PSMA-11 PET/CT Study in Prostate Cancer Patients after Radical Prostatectomy.

Objective: The objective of this study was to identify the optimal cut-off value of prostate specific antigen (PSA) to assess the extent of the disease in [Ga]Ga-PSMA-11 PET/CT study in patients after radical prostatectomy.

Materials And Methods: Retrospective analysis was performed on a group of 215 patients who underwent a [Ga]Ga-PSMA-11 PET/CT examination because of suspected recurrence after radical prostatectomy. Patients were divided into four groups: 1, no active lesions suggesting recurrence (n = 92); 2, suspected isolated local recurrence (n = 19); 3, oligometastatic disease (n = 82); and 4, polymetastatic disease (n = 22).

99mTc-labeled vasopressin peptide as a radiopharmaceutical for small-cell lung cancer (SCLC) diagnosis.

The 99mTc-labeled conjugates of the vasopressin (AVP) peptide and of its analogue d(CH2)5[D-Tyr(Et2)-Ile4-Eda9]AVP (AVP(an)) have been synthesized using the technetium complexes with tetradentate tripodal chelator (the tris(2-mercaptoethyl)amine (NS3)) and the monodentate isocyanide ligand (CN-peptide). The conjugates exhibit high stability in the presence of 100 times the molar excess of standard amino acids cysteine or histidine and also satisfactory stability in human serum. The 99mTc(NS3)(CN-AVP) and 99mTc(NS3)(CN-AVP(an)) ability of binding to small-cell lung cancer (SCLC) cell line H69 was studied in vitro.

The diagnostic role of 68Ga-DOTATATE PET/CT in the detection of neuroendocrine tumours.

Background: Positron emission tomography (PET) combined with computer tomography (CT) using (68)Ga-DOTATATE is a promising method for the evaluation of patients with recognised or suspected neuroendocrine tumours (NET). The aim of this study was to assess the diagnostic value of (68)Ga-DOTATATE PET/CT in the visualisation of the expression of somatostatin receptors (SSTR) and identification of new lesions.

Material And Methods: Between December 2009 and January 2011 ninety-seven patients with confirmed (88 cases) or suspected (9 cases) NET underwent (68)Ga DOTATATE PET/CT.