Synthesis and in Vivo Evaluation of [123I]Melanin-Targeted Agents.

This study reports the synthesis, [(123)I]radiolabeling, and biological profile of a new series of iodinated compounds for potential translation to the corresponding [(131)I]radiolabeled compounds for radionuclide therapy of melanoma. Radiolabeling was achieved via standard electrophilic iododestannylation in 60-90% radiochemical yield. Preliminary SPECT imaging demonstrated high and distinct tumor uptake of all compounds, as well as high tumor-to-background ratios compared to the literature compound [(123)I]4 (ICF01012).

¹⁸F-FDG PET/CT following chemoradiation of uterine cervix cancer provides powerful prognostic stratification independent of HPV status: a prospective cohort of 105 women with mature survival data.

Purpose: To report 5-year outcomes of a prospective registry study investigating posttherapy FDG PET/CT in women with locally advanced cervical cancer. A secondary analysis assessing the prognostic significance of HPV infection was performed.

Methods: Patients underwent definitive chemoradiation followed by a single FDG PET/CT scan for response assessment.

15-Year Experience of 18F-FDG PET Imaging in Response Assessment and Restaging After Definitive Treatment of Merkel Cell Carcinoma.

Unlabelled: The objective of this study was to evaluate the utility of (18)F-FDG PET in restaging and response assessment of patients who underwent definitive treatment for Merkel cell carcinoma (MCC).

Methods: A retrospective review of patients undergoing (18)F-FDG PET imaging for MCC between January 1997 and October 2010 at the Peter MacCallum Cancer Centre with follow-up until February 2015 was performed. Data analysis was performed on patients who were treated definitively and underwent post-treatment PET imaging performed either as a restaging scan for ongoing monitoring, suspicion of recurrence, or assessment for suitability of salvage treatment or as response assessment within 1-6 mo of treatment.

Moving Beyond "Lumpology": PET/CT Imaging of Pheochromocytoma and Paraganglioma.

High somatostatin receptor expression on the cell membrane of succinate dehydrogenase mutation-related pheochromocytoma and paraganglioma provides a potential target for imaging and therapy. (68)Ga-DOTATATE positron emission PET/CT may represent a new gold standard for staging pheochromocytoma/paraganglioma and have future therapeutic implications.

Pulmonary Scintigraphy for the Diagnosis of Acute Pulmonary Embolism: A Survey of Current Practices in Australia, Canada, and France.

Unlabelled: There are currently no data published regarding the proportion of nuclear medicine centers using SPECT or SPECT/CT rather than planar ventilation/perfusion (V/Q) imaging in patients with suspected acute pulmonary embolism (PE). Furthermore, the reporting criteria used for interpretation of both planar and SPECT V/Q scans are variable and data are lacking regarding which criteria are commonly used in various centers. The aim of this study was to assess current practices regarding the performance and interpretation of lung scintigraphy across 3 different countries.

Dosimetric Consequences of 3D Versus 4D PET/CT for Target Delineation of Lung Stereotactic Radiotherapy.

Introduction: Lung tumor delineation is frequently performed using 3D positron emission tomography (PET)/computed tomography (CT), particularly in the radiotherapy treatment planning position, by generating an internal target volume (ITV) from the slow acquisition PET. We investigate the dosimetric consequences of stereotactic ablative body radiotherapy (SABR) planning on 3D PET/CT in comparison with gated (4D) PET/CT.

Methods: In a prospective clinical trial, patients with lung metastases were prescribed 26 Gy single-fraction SABR to the covering isodose.

High-resolution pulmonary ventilation and perfusion PET/CT allows for functionally adapted intensity modulated radiotherapy in lung cancer.

Background And Purpose: To assess the utility of functional lung avoidance using IMRT informed by four-dimensional (4D) ventilation/perfusion (V/Q) PET/CT.

Materials And Methods: In a prospective clinical trial, patients with non-small cell lung cancer (NSCLC) underwent 4D-V/Q PET/CT scanning before 60Gy of definitive chemoradiation. Both "highly perfused" (HPLung) and "highly ventilated" (HVLung) lung volumes were delineated using a 70th centile SUV threshold, and a "ventilated lung volume" (VLung) was created using a 50th centile SUV threshold.

Noninvasive monitoring of diffuse large B-cell lymphoma by immunoglobulin high-throughput sequencing.

Recent studies have shown limited utility of routine surveillance imaging for diffuse large B-cell lymphoma (DLBCL) patients achieving remission. Detection of molecular disease by immunoglobulin high-throughput sequencing (Ig-HTS) from peripheral blood provides an alternate strategy for surveillance. We prospectively evaluated the utility of Ig-HTS within 311 blood and 105 tumor samples from 75 patients with DLBCL, comparing Ig-HTS from the cellular (circulating leukocytes) and acellular (plasma cell-free DNA) compartments of peripheral blood to clinical outcomes and (18)fluoro-deoxyglucose positron emission tomography combined with computed tomography (PET/CT; n = 173).

Respiratory-gated (4D) FDG-PET detects tumour and normal lung response after stereotactic radiotherapy for pulmonary metastases.

Background: Response assessment after stereotactic ablative body radiotherapy (SABR) in lung can be confounded by radiation-induced inflammation, fibrosis and subsequent alteration of tumour motion. The purpose of this prospective pilot study was to evaluate the utility of four-dimensional (4D) FDG-PET/CT for post-SABR tumour and normal lung response assessment in pulmonary oligometastases.

Material And Methods: Patients enrolled from February 2010 to December 2011 in this prospective ethics approved study had 1-2 pulmonary metastases on staging FDG-PET.

Lung cancer.

(18)F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) plays a key role in the evaluation of undiagnosed lung nodules, when primary lung cancer is strongly suspected, or when it has already been diagnosed by other techniques. Although technical factors may compromise characterization of small or highly mobile lesions, lesions without apparent FDG uptake can generally be safely observed, whereas FDG-avid lung nodules almost always need further evaluation. FDG-PET/CT is now the primary staging imaging modality for patients with lung cancer who are being considered for curative therapy with either surgery or definitive radiation therapy.

The evolving role of molecular imaging in non-small cell lung cancer radiotherapy.

Molecular imaging with positron emission tomography (PET) has dramatically changed the management of patients with lung cancer who are treated with radiotherapy. Uptake of the most widely used PET radiopharmaceutical (18)F-fluorodeoxyglucose identifies lung nodules or intrathoracic lymph nodes as likely to be malignant and frequently identifies previously unsuspected sites of malignant disease outside the thorax. Patients with non-small cell lung cancer, especially those with apparently more advanced locoregional disease to start with, are often upstaged, and this has a profound effect on their subsequent management.

Somatostatin receptor imaging with 68Ga DOTATATE PET/CT: clinical utility, normal patterns, pearls, and pitfalls in interpretation.

Gallium 68 ((68)Ga) 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-octreotate (DOTATATE, GaTate) positron emission tomography (PET)/computed tomography (CT) is an imaging technique for detecting and characterizing neuroendocrine tumors (NETs). GaTate, a somatostatin analog, has recently been accorded orphan drug status by the U.S.

Improving patient selection for 18F-FDG PET scanning in the staging of gastric cancer.

Unlabelled: Standard pretreatment staging for gastric cancer includes CT of the chest, abdomen, and pelvis; gastroscopy; and laparoscopy. Although (18)F-PET combined with CT has proven to be a useful staging tool in many cancers, some gastric cancers are not (18)F-FDG-avid and its clinical value is still debatable.

Methods: Gastric cancer patients who underwent staging (18)F-FDG PET scans from 2002 to 2013 at the Peter MacCallum Cancer Center were retrospectively analyzed, and a systematic review was also conducted using PubMed between 2000 to March 2014 to investigate clinicopathologic parameters associated with (18)F-FDG avidity.

Analysis of 177Lu-DOTA-octreotate therapy-induced DNA damage in peripheral blood lymphocytes of patients with neuroendocrine tumors.

Unlabelled: Ionizing radiation-induced DNA double-strand breaks (DSBs) can lead to cell death, genome instability, and carcinogenesis. Immunofluorescence detection of phosphorylated histone variant H2AX (γ-H2AX) is a reliable and sensitive technique to monitor external-beam ionizing radiation-induced DSBs in peripheral blood lymphocytes (PBLs). Here, we investigated whether γ-H2AX could be used as an in vivo marker to assess normal-tissue toxicity after extended internal irradiation with (177)Lu-DOTA-octreotate (LuTate) peptide receptor radionuclide therapy (PRRT) of neuroendocrine tumors.

The role of positron emission tomography/computed tomography in planning radiotherapy in endometrial cancer.

Objective: The optimal method of assessing disease distribution in endometrial cancer is widely debated. Knowledge of disease distribution assists in planning adjuvant radiotherapy; in this study we used positron emission tomography/computed tomography (PET/CT) to assess disease distribution before radiotherapy.

Methods: Seventy-three consecutive patients referred to the Peter MacCallum Cancer Centre for adjuvant radiotherapy for endometrial cancer, with either high-risk disease after a hysterectomy or recurrent disease, had a PET/CT before treatment.

A prospective investigation into the clinical impact of 4D-PET/CT in the characterisation of solitary pulmonary nodules.

Background: While the effects of respiratory motion on measuring metabolic signal in PET/CT scanning are well known, it is still standard practice in most centres to scan patients while breathing freely with no correction for the effects of respiratory motion. The aim of this study was to investigate the impact of 4D-PET/CT in classifying lesions in patients with a radiologically-indeterminate solitary pulmonary nodule.

Methods: Twenty consecutive patients with a solitary pulmonary nodule for investigation were prospectively recruited and completed a whole-body (WB)-PET/CT and 4D-PET/CT in the same session.

The utility of 18 F-FDG PET/CT for suspected recurrent breast cancer: impact and prognostic stratification.

Background: The incremental value of 18FDG PET/CT in patients with breast cancer (BC) compared to conventional imaging (CI) in clinical practice is unclear. The aim of this study was to evaluate the management impact and prognostic value of 18 F-FDG PET/CT in this setting.

Methods: Sixty-three patients who were referred to our institution for suspicion of BC relapse were retrospectively enrolled.

Ga-68 MAA Perfusion 4D-PET/CT Scanning Allows for Functional Lung Avoidance Using Conformal Radiation Therapy Planning.

Background: Ga-68-macroaggregated albumin ((68)Ga-perfusion) positron emission tomography/computed tomography (PET/CT) is a novel imaging technique for the assessment of functional lung volumes. The purpose of this study was to use this imaging technique for functional adaptation of definitive radiotherapy plans in patients with non-small cell lung cancer (NSCLC).

Methods: This was a prospective clinical trial of patients with NSCLC who received definitive 3-dimensional (3D) conformal radiotherapy to 60 Gy in 30 fx and underwent pretreatment respiratory-gated (4-dimensional [4D]) perfusion PET/CT.

The genomic landscape of phaeochromocytoma.

Phaeochromocytomas (PCCs) and paragangliomas (PGLs) are rare neural crest-derived tumours originating from adrenal chromaffin cells or extra-adrenal sympathetic and parasympathetic tissues. More than a third of PCC/PGL cases are associated with heritable syndromes involving 13 or more known genes. These genes have been broadly partitioned into two groups based on pseudo-hypoxic and receptor tyrosine kinase (RTK) signalling pathways.

Geographic miss of lung tumours due to respiratory motion: a comparison of 3D vs 4D PET/CT defined target volumes.

Background: PET/CT scans acquired in the radiotherapy treatment position are typically performed without compensating for respiratory motion. The purpose of this study was to investigate geographic miss of lung tumours due to respiratory motion for target volumes defined on a standard 3D-PET/CT.

Methods: 29 patients staged for pulmonary malignancy who completed both a 3D-PET/CT and 4D-PET/CT were included.