Differential Metabolism and Pharmacokinetics of L-[1-(11)C]-Methionine and 2-[(18)F] Fluoro-2-deoxy-D-glucose (FDG) in Androgen Independent Prostate Cancer.

Metabolic imaging with positron emission tomography (PET) for the staging and monitoring of treatment response has important implications in clinical oncology. The choice of radiotracer is likely to be critically important. The objective of our study was to compare the pharmacokinetics of C-11-methionine with FDG in a group of androgen independent patients with metastatic prostate cancer, to determine the differential metabolism of the two tracers, and to determine the optimal time of imaging after injection in treated and untreated patients.

Tumor Treatment Response Based on Visual and Quantitative Changes in Global Tumor Glycolysis Using PET-FDG Imaging. The Visual Response Score and the Change in Total Lesion Glycolysis.

"Functional" tumor treatment response parameters have been developed to measure treatment induced biochemical changes in the entire tumor mass, using positron emission tomography (PET) and [F-18] fludeoxyglucose (FDG). These new parameters are intended to measure global changes in tumor glycolysis. The response parameters are determined by comparing the pre- and posttreatment PET-FDG images either visually from the change in image appearance in the region of the tumor, or quantitatively based on features of the calibrated digital PET image.

Targeted alpha particle immunotherapy for myeloid leukemia.

Unlike beta particle-emitting isotopes, alpha emitters can selectively kill individual cancer cells with a single atomic decay. HuM195, a humanized anti-CD33 monoclonal antibody, specifically targets myeloid leukemia cells and has activity against minimal disease. When labeled with the beta-emitters (131)I and (90)Y, HuM195 can eliminate large leukemic burdens in patients, but it produces prolonged myelosuppression requiring hematopoietic stem cell transplantation at high doses.

Measurements of tumor tissue oxygen tension using a time-resolved luminescence-based optical oxylite probe: comparison with a paired survival assay.

Recently, a system that measures tissue oxygen tension using time-resolved luminescence-based optical sensors has become available commercially (Oxford Optronix, Oxford, England). Two experiments were conducted using this system. First, the oxygen tension distribution was measured in two tumor lines: a spontaneous mouse fibrosarcoma, FSa-II, and a human squamous cell carcinoma xenograft, FaDu.

Effect of respiratory gating on quantifying PET images of lung cancer.

Unlabelled: We have developed a new technique to gate lung 18F-FDG PET images in synchronization with the respiratory motion to reduce smearing due to breathing and improve quantitation of 18F-FDG uptake in lung lesions.

Methods: A camera-based respiratory gating system, the real-time position management (RPM), is used to monitor the respiratory cycle. The RPM provides a trigger to the PET scanner to initiate the gating cycle.

Iodination of annexin V for imaging apoptosis.

Unlabelled: Our goal in this investigation was to develop a method for iodinating annexin V that would be suitable for the in vivo detection of apoptosis.

Methods: Annexin V was iodinated with (125)I using 2 different techniques: direct iodination with IODO-BEADS, resulting in the iodination of tyrosine residues; and use of the Bolton-Hunter reagent, which binds to lysine. The active fraction of the labeled preparation was purified by affinity chromatography.

Rationales, evidence, and design considerations for fractionated radioimmunotherapy.

Although fractionation can be used in a discrete radiobiologic sense, herein it is generally used in the broader context of administration of multiple, rather than single, doses of radionuclide for radioimmunotherapy (RIT) or other targeted radionuclide therapies. Fractionation is a strategy for overcoming heterogeneity of monoclonal antibody (MAb) distribution in the tumor and the consequent nonuniformity of tumor radiation doses. Additional advantages of fractionated RIT are the ability to 1) provide patient-specific radionuclide and radiation dosing, 2) control toxicity by titration of the individual patient, 3) reduce toxicity, 4) increase the maximum tolerated dose (MTD) for many patients, 5) increase tumor radiation dose and efficacy, and 6) prolong tumor response by permitting treatment over time.

Radiotherapy treatment planning for patients with non-small cell lung cancer using positron emission tomography (PET).

Purpose: Many patients with non-small cell lung cancer (NSCLC) receive external beam radiation therapy as part of their treatment. Three-dimensional conformal radiation therapy (3DCRT) commonly uses computed tomography (CT) to accurately delineate the target lesion and normal tissues. Clinical studies, however, indicate that positron emission tomography (PET) has higher sensitivity than CT in detecting and staging of mediastinal metastases.