Synthesis, Preclinical Toxicity, and Biodistribution of [F]AVT-011 to Assess the P-Glycoprotein Function.

Many studies have reported the role of P-glycoprotein (Pgp) in chemoresistance in various pathological conditions such as cancer and neurodegenerative diseases, such as Alzheimer's. In this study, we are reporting the high-performance liquid chromatography (HPLC)-based purification of fluorine-18 [F]AVT-011 and its preclinical evaluation. AVT-011 was labeled with F using the nucleophilic substitution method by heating the reaction mixture at 110°C for 10 min, followed by purification using preparative HPLC and C18ec cartridge.

Synthesis, characterization, and radiosynthesis of fluorine-18-AVT-011 as a Pgp chemoresistance imaging marker.

P-glycoprotein (Pgp) is the most studied ATP-binding cassette (ABC) efflux transporter and contributes to chemoresistance. A few tracers have been developed to detect the in-vivo status of chemoresistance using positron emission tomography (PET) imaging. In our study, we have synthesized labeled AVT-011 with fluorine-18 (F) followed by in-vitro and in-vivo analysis.

Lung clearance of inhaled aerosol of Tc-99m-methoxyisobutyl isonitrile: relationships with cigarette smoking, age and gender.

Tc-99m-methoxyisobutyl isonitrile (Tc-99m-MIBI) is a radiolabelled xenobiotic, the disappearance rate of which from lungs following inhalation as a radioaerosol correlates inversely with bronchopulmonary multidrug resistance protein 1 (MRP1) expression. Tc-99m-MIBI clearance has previously been shown to be delayed in cigarette smokers. The aim of the current study was to determine whether smoking correlates with bronchopulmonary MRP1 expression, to confirm that Tc-99m-MIBI disappearance rate from the lungs following inhalation is delayed in smokers, and to determine the effects of gender and age on disappearance rate.

Does the Clearance of Inhaled (99m)Tc-Sestamibi Correlate with Multidrug Resistance Protein 1 Expression in the Human Lung?

Purpose To examine the relation between the lung elimination rate of inhaled technetium 99m ((99m)Tc)-sestamibi and immunohistochemical expression of bronchopulmonary multidrug resistance protein 1 (MRP1) and permeability glycoprotein (P-gp) and assess the repeatability of the inhaled (99m)Tc-sestamibi clearance technique. Materials and Methods (99m)Tc-sestamibi is a known substrate for P-gp and MRP1, which are established cellular drug efflux transporters. The elimination rate of (99m)Tc-sestamibi from the lungs after inhalation as an aerosol has been hypothesized to be regulated by expression of these transporters.

Clinical Utility of SPECT/CT Imaging Post-Radioiodine Therapy: Does It Enhance Patient Management in Thyroid Cancer?

Background: The aim of this study was to evaluate post-therapy iodine-131 single-photon emission computed tomography/computed tomography ((131)I-SPECT/CT) imaging in comparison to conventional planar (131)I whole-body imaging, and to assess its clinical impact on the management of patients.

Methods: We retrospectively reviewed planar (131)I whole-body and (131)I-SPECT/CT imaging findings in 67 patients who underwent (131)I therapy for thyroid cancer. Two nuclear medicine physicians reviewed the scans independently.

Incidence and Significance of Incidental Focal Thyroid Uptake on (18)F-FDG PET Study in a Large Patient Cohort: Retrospective Single-Centre Experience in the United Kingdom.

Objective: To assess the prevalence and pathological nature of incidental focal thyroid uptake on (18)F-FDG (2-[(18)F]-fluoro-2-deoxy-D-glucose) PET (positron emission tomography) and examine the role of the maximum standardised uptake value (SUVmax) to differentiate benign from malignant thyroid pathology.

Material And Methods: (18)F-FDG PET reports were retrospectively reviewed. Incidental focal tracer uptake in the thyroid was noted in 147 patients (0.

Metastasis to the thyroid from non-small cell carcinoma of the lung: findings in (18)F-FDG PET/CT study.

The incidence of thyroid metastasis from other primary malignancy is rare. In this case, we present the findings of (18)F-FDG PET/CT in thyroid metastasis from underlying non-small cell carcinoma of the lung and highlight the importance of tracer uptake pattern recognition within the thyroid on (18)F-FDG PET/CT study.

Value of lateral blood pool imaging in patients with suspected stress fractures of the tibia.

Aim: To critically evaluate the use of lateral blood pool imaging in athletes with lower limb pain and with a clinical suspicion of stress fracture.

Methods: Two experienced nuclear medicine physicians evaluated 3-phase bone scans using 99mTc-methylene diphosphonate performed in 50 consecutive patients referred from a specialist sports injury clinic for suspected tibial stress fracture. The vascularity to the tibia as seen on the blood pool (second phase) images in the anterior/posterior views was compared with the lateral/medial view assessments.

Beware of the focal uptake at the ischium on the bone scan in prostate cancer.

Rationale: The isotope bone scan is routinely used in the management of prostate cancer as the skeleton is the second most common area of metastasis after lymph nodes. A classic site of involvement in the pelvis is the ischium, and the aim of this study was to assess the value of single-photon emission computed tomography/computed tomography (SPECT/CT) imaging in patients with focal ischial uptake on the planar scan.

Materials And Methods: This was a retrospective study of consecutive 150 patients with prostate cancer who were referred for a whole-body bone scan between August 2007 and 2008.

The added value of multislice SPECT/CT in patients with equivocal bony metastasis from carcinoma of the prostate.

Purpose: The purpose of this study was to investigate the additional value of single photon emission computed tomography/computed tomography (SPECT/CT) over whole-body planar bone scintigraphy and SPECT in prostate cancer patients in terms of diagnostic confidence, inter-reviewer agreement and the possible impact on the clinical management.

Methods: This was a retrospective review of 40 consecutive prostate cancer patients (mean age 71 years) who underwent (99m)Tc-methylene diphosphonate (MDP) whole-body planar bone scintigraphy, SPECT and SPECT/CT between April 2006 and April 2008. The images were evaluated by two independent reviewers; inter-reviewer agreement was evaluated using a weighted kappa score.

SPECT/CT in imaging foot and ankle pathology-the demise of other coregistration techniques.

Disorders of the ankle and foot are common and given the complex anatomy and function of the foot, they present a significant clinical challenge. Imaging plays a crucial role in the management of these patients, with multiple imaging options available to the clinician. The American College of radiology has set the appropriateness criteria for the use of the available investigating modalities in the management of foot and ankle pathologies.

Cost-effectiveness of 99mTc-sestamibi in predicting response to chemotherapy in patients with lung cancer: systematic review and meta-analysis.

Unlabelled: Multidrug resistance (MDR) is a major problem in lung cancer. (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) has been demonstrated to be a noninvasive marker for the diagnosis of MDR-related P glycoprotein and MDR-associated protein expression in various solid tumors. Studies have shown that (99m)Tc-MIBI could play a significant role in the management of lung cancer; for example, it could be used in the selection of patients for chemotherapy or radiotherapy or in combined protocols before the start of treatment.

Synergistic impact of attenuation correction and gating in routine myocardial SPECT reporting: 2 year follow-up study.

Aim: To look at the combined impact of non-uniform attenuation correction (AC) and gated SPECT in the visual interpretation of myocardial SPECT imaging. This was compared to the individual benefit obtained by adding AC information and gated SPECT information to non-AC image information.

Materials: We retrospectively studied a group of 141 patients with a 22-26 month follow-up who underwent myocardial perfusion scintigraphy imaging.

Thyroid hormone and parathyroid hormone competing to maintain calcium levels in the presence of vitamin D deficiency.

Weight loss and bone disease in the elderly are very often attributed to malignancy. Rarely, benign treatable conditions may be overlooked. Thyrotoxicosis, a benign treatable condition, needs to be excluded in such patients.