Deep learning based identification of bone scintigraphies containing metastatic bone disease foci.

Purpose: Metastatic bone disease (MBD) is the most common form of metastases, most frequently deriving from prostate cancer. MBD is screened with bone scintigraphy (BS), which have high sensitivity but low specificity for the diagnosis of MBD, often requiring further investigations. Deep learning (DL) - a machine learning technique designed to mimic human neuronal interactions- has shown promise in the field of medical imaging analysis for different purposes, including segmentation and classification of lesions.

Deconvolution of Tc-99m-Mercaptoacetyltriglycine Renograms with the Concomitant Use of a Sparse Legendre Polynomial Representation and the Moore-Penrose Pseudo-inverse.

Objectives: This study aimed to introduce an improved deconvolution technique for Tc-99m-mercaptoacetyltriglycine renograms based on the combination of a sparse Legendre polynomial representation and the Moore-Penrose inversion matrix (LG). This method reduces the effect of noise on the measurement of renal retention function transit time (TT).

Methods: The stability and accuracy of the proposed method were tested using a renal database containing Monte Carlo-simulated studies and real adult patient data.

Individualized Prophylactic Neck Irradiation in Patients with cN0 Head and Neck Cancer Based on Sentinel Lymph Node(s) Identification: Definitive Results of a Prospective Phase 1-2 Study.

Purpose: This prospective, nonrandomized, interventional phase 1-2 study investigated the individualization of elective node irradiation in clinically N0 head and neck squamous cell carcinoma by sentinel lymph node (SLN) mapping with single-photon emission computed tomography/computed tomography (SPECT/CT) and its impact on tumor control and radiation-related toxicity.

Methods And Materials: Forty-four patients with clinically N0 head and neck squamous cell carcinoma treated with definitive (chemo-)radiation therapy were imaged with SPECT/CT after Tc nanocolloid injection around the tumor. The neck levels containing up to the 4 hottest SLNs were selected for prophylactic irradiation.

An individualized radiation dose escalation trial in non-small cell lung cancer based on FDG-PET imaging.

Aim: The aim of the study was to assess the feasibility of an individualized 18F fluorodeoxyglucose positron emission tomography (FDG-PET)-guided dose escalation boost in non-small cell lung cancer (NSCLC) patients and to assess its impact on local tumor control and toxicity.

Patients And Methods: A total of 13 patients with stage II-III NSCLC were enrolled to receive a dose of 62.5 Gy in 25 fractions to the CT-based planning target volume (PTV; primary turmor and affected lymph nodes).

Correlation analysis of [F]fluorodeoxyglucose and [F]fluoroazomycin arabinoside uptake distributions in lung tumours during radiation therapy.

Background: PET-guided dose painting (DP) aims to target radioresistant tumour regions in order to improve radiotherapy (RT) outcome. Besides the well-known [F]fluorodeoxyglucose (FDG), the hypoxia positron emission tomography (PET) tracer [F]fluoroazomycin arabinoside (FAZA) could provide further useful information to guide the radiation dose prescription. In this study, we compare the spatial distributions of FDG and FAZA PET uptakes in lung tumours.

Evolution of [F]fluorodeoxyglucose and [F]fluoroazomycin arabinoside PET uptake distributions in lung tumours during radiation therapy.

Background: Dose painting (DP) aims to improve radiation therapy (RT) outcome by targeting radioresistant tumour regions identified through functional imaging, e.g., positron emission tomography (PET).

αVβ3 integrin-targeted microSPECT/CT imaging of inflamed atherosclerotic plaques in mice.

Background: αVβ3-integrin is expressed by activated endothelial cells and macrophages in atherosclerotic plaques and may represent a valuable marker of high-risk plaques. We evaluated (99m)Tc-maraciclatide, an integrin-specific tracer, for imaging vascular inflammation in atherosclerotic lesions in mice.

Methods: Apolipoprotein E-negative (ApoE(-/-)) mice on a Western diet (n = 10) and normally fed adult C57BL/6 control mice (n = 4) were injected with (99m)Tc-maraciclatide (51.

Methodology for adaptive and robust FDG-PET escalated dose painting by numbers in head and neck tumors.

Objective: To develop a methodology for using FDG PET/CT in adaptive dose painting by numbers (DPBN) in head and neck squamous cell carcinoma (HNSCC) patients. Issues related to noise in PET and treatment robustness against geometric errors are addressed.

Methods: Five patients with locally advanced HNSCC scheduled for chemo-radiotherapy were imaged with FDG-PET/CT at baseline and 2-3 times during radiotherapy (RT).

Dynamic contrast-enhanced computed tomography to assess early activity of cetuximab in squamous cell carcinoma of the head and neck.

Background: Cetuximab, a monoclonal antibody targeting the Epidermal Growth Factor Receptor (EGFR), has demonstrated activity in various tumor types. Using dynamic contrast-enhanced computed tomography (DCE-CT), we investigated the early activity of cetuximab monotherapy in previously untreated patients with squamous cell carcinoma of the head and neck (SCCHN).

Methods: Treatment-naïve patients with SCCHN received cetuximab for 2 weeks before curative surgery.

PET imaging biomarkers in head and neck cancer.

In locally advanced head and neck squamous cell carcinoma (HNSCC), the role of imaging becomes more and more critical in the management process. In this framework, molecular imaging techniques such as PET allow noninvasive assessment of a range of tumour biomarkers such as metabolism, hypoxia and proliferation, which can serve different purposes. First, in a pretreatment setting they can influence therapy selection strategies and target delineation for radiation therapy.

Hypoxia-guided adaptive radiation dose escalation in head and neck carcinoma: a planning study.

Objective: To evaluate from a planning point of view the dose distribution of adaptive radiation dose escalation in head and neck squamous cell carcinoma (HNSCC) using (18)F-Fluoroazomycin arabinoside (FAZA) positron emission tomography/computed tomography (PET-CT).

Material/methods: Twelve patients with locally advanced HNSCC underwent three FAZA PET-CT before treatment, after 7 fractions and after 17 fractions of a carboplatin-5FU chemo-radiotherapy regimen (70 Gy in 2 Gy per fraction over 7 weeks). The dose constraints were that every hypoxic voxel delineated before and during treatment (newborn hypoxic voxels) should receive a total dose of 86 Gy.

High 18F-FDG uptake in a systemic right ventricle after atrial switch.

A 21-year-old patient with a D-transposition of the great arteries and a single coronary ostium underwent an atrial switch operation as newborn (Senning correction at 6 days of life in 1992). For an unrelated oncological evaluation, she underwent a recent F-FDG PET/CT. The myocardial uptake was clearly more intense in the morphological right ventricle, as this ventricle has become the systemic ventricle.

A randomized trial on the optimization of 18F-FDG myocardial uptake suppression: implications for vulnerable coronary plaque imaging.

Unlabelled: (18)F-FDG PET/CT can be used to detect arterial atherosclerotic plaque inflammation. However, avid myocardial glucose uptake may preclude its use for visualizing coronary plaques. Fatty acid loading or calcium channel blockers could decrease myocardial (18)F-FDG uptake, thus assisting coronary plaque inflammation identification.

Advances in the management of squamous cell carcinoma of the head and neck.

Squamous cell carcinoma of the head and neck (SCCHN) is the sixth most common cancer worldwide. The main risk factors for cancers of the oral cavity, larynx, oropharynx, and hypopharynx are alcohol and tobacco use. In addition, the human papillomavirus (HPV) is an established cause of oropharyngeal cancer.

A prospective clinical study of ¹⁸F-FAZA PET-CT hypoxia imaging in head and neck squamous cell carcinoma before and during radiation therapy.

Purpose: Hypoxia in head and neck squamous cell carcinoma (HNSCC) is associated with poor prognosis and outcome. (18) F-Fluoroazomycin arabinoside (FAZA) is a positron emission tomography (PET) tracer developed to enable identification of hypoxic regions within tumor. The aim of this study was to evaluate the use of (18) F-FAZA-PET for assessment of hypoxia before and during radiation therapy.

Tumour control probability derived from dose distribution in homogeneous and heterogeneous models: assuming similar pharmacokinetics, (125)Sn-(177)Lu is superior to (90)Y-(177)Lu in peptide receptor radiotherapy.

Clinical trials on (177)Lu-(90)Y therapy used empirical activity ratios. Radionuclides (RN) with larger beta maximal range could favourably replace (90)Y. Our aim is to provide RN dose-deposition kernels and to compare the tumour control probability (TCP) of RN combinations.

The role of neck dissection in the setting of chemoradiation therapy for head and neck squamous cell carcinoma with advanced neck disease.

Concurrent chemotherapy and radiotherapy (CRT) has become standard treatment for many patients with advanced head and neck squamous cell carcinoma (HNSCC). This has led to controversy concerning the role of neck dissection (ND) in this setting. The current debate is focused on N2-N3 disease and the ability of a clinical complete response to predict the absence of viable cells in the ND specimen.

Effect of interferon-alpha treatment on [68Ga-DOTA,Tyr3,Thre8]octreotide uptake in CA20948 tumors: a small-animal PET study.

Unlabelled: In peptide receptor radionuclide therapy of neuroendocrine tumors, improvements have been made by increasing the affinity for receptors and by protecting critical organs (e.g., kidneys).

Tumor uptake of 68Ga-DOTA-Tyr3-octreotate: animal PET studies of tumor flow and acute somatostatin receptor modulation in the CA20948 rat model.

Introduction: Factors determining the in vivo uptake of radiolabeled somatostatin analogs by neuroendocrine tumors are poorly known. The aim is to evaluate in vivo tumor perfusion and regulation of somatostatin receptors (sstr) following acute exposure to octreotide, in an animal model of neuroendocrine tumor.

Methods: H(2)(15)O flow studies were performed in 8 CA20948 tumor-bearing rats and another 36 rats underwent three [(68)Ga]-DOTA-Tyr(3)-octreotate imaging sessions at 24-h intervals.

Prognostic value of FDG uptake in early stage non-small cell lung cancer.

Background: Non-small cell lung cancer (NSCLC) has a poor prognosis even for early stages of the disease (stage I and II). We studied the prognostic value of PET FDG in patients with completely resected stage I and II NSCLC.

Methods: Retrospective study of 96 patients with NSCLC whose staging included 18F-FDG PET (fluoro deoxy glucose positron emission tomography).