Essentials
Patients at high‐risk of occult cancer may benefit from extensive screening.
We validated the RIETE cancer score in the MVTEP study.
One in three patients were classified as high‐risk, 10% ...of whom had cancer diagnosed.
The RIETE score identifies a subgroup at high risk for cancer.
Summary
Background
Most recent trials evaluating extensive screening strategies for occult cancer in patients with unprovoked venous thromboembolism have failed, because, among other reasons, of an overall low rate of occult cancer. The RIETE investigators recently proposed a score aimed at identifying a subgroup at higher risk.
Methods
We retrospectively computed the RIETE score for all patients included in the MVTEP study, which evaluated the accuracy of ¹⁸Ffluorodeoxyglucose‐positron emission tomography in the screening of occult cancer in patients with unprovoked venous thromboembolism. Performance of the RIETE score was assessed according to the proportion of patients classified in each risk group, and the corresponding rates of cancer diagnosis.
Results
Among the 386 patients included in the analysis, 136 patients (35.3%) were classified as high risk by the RIETE score. Cancer was diagnosed in 16 (11.8%) of them, whereas it was diagnosed in nine (3.6%) of the 250 patients with a low RIETE cancer score: odds ratio of 3.6 (95% confidence interval CI 1.53–8.32). The area under the receiver operating characteristic curve was 0.63 (95% CI 0.51–0.74).
Conclusion
The RIETE score seems to be able to identify a subgroup at high risk for cancer (10%) in our specific dataset of patients with unprovoked venous thromboembolism.
Over the last decades, the refinement of radiation therapy techniques has been associated with an increasing interest for individualized radiation therapy with the aim of increasing or maintaining ...tumor control and reducing radiation toxicity. Developments in artificial intelligence (AI), particularly machine learning and deep learning, in imaging sciences, including nuclear medecine, have led to significant enthusiasm for the concept of “rapid learning health system”. AI combined with radiomics applied to (18F)-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) offers a unique opportunity for the development of predictive models that can help stratify each patient's risk and guide treatment decisions for optimal outcomes and quality of life of patients treated with radiation therapy. Here we present an overview of the current contribution of AI and radiomics-based machine learning models applied to (18F)-FDG PET/CT in the management of cancer treated by radiation therapy.
Au cours des dernières décennies, l’amélioration des techniques de radiothérapie a été associée à un intérêt croissant pour la personnalisation de la radiothérapie afin d’augmenter ou de maintenir le taux de contrôle tumoral tout en réduisant la toxicité des rayonnements. Les progrès de l’intelligence artificielle (IA), en particulier de l’apprentissage automatique et de l’apprentissage profond, dans les domaines de l’imagerie, y compris la médecine nucléaire, ont suscité un grand enthousiasme pour le concept de « système de santé à apprentissage rapide ». L’IA combinée à la radiomique appliquée à la tomographie par émission de positons/tomodensitométrie (TEP/TDM) au (18F)-fluorodésoxyglucose (18F-FDG) offre une opportunité unique pour le développement de modèles prédictifs qui peuvent aider à stratifier le risque de chaque patient et guider les décisions de traitement pour des résultats thérapeutiques optimaux et une amélioration de la qualité de vie des patients traités par irradiation. Nous présentons ici une vue d’ensemble du rôle actuel de l’IA et des modèles radiomiques basés sur l’apprentissage automatique appliqué à la TEP/TDM au (18F)-FDG dans la prise en charge des cancers traités par irradiation.
Unprovoked venous thromboembolism (VTE) may be the first manifestation of an underlying cancer. We aimed to assess the period prevalence of occult cancer detection stratified by VTE location (deep ...vein thrombosis DVT, pulmonary embolism PE or both) and the anatomical relationship between occult cancer and VTE.
Post-hoc analysis of a systematic review and individual patient data meta-analysis of adults with unprovoked VTE with at least 12 months of follow-up. Cancer types were grouped according to thoracic, abdomino-pelvic, or other locations.
A total of 2300 patients were eligible including 1218 with DVT only (53%), 719 with PE only (31%), and 363 with both PE and DVT (16%). The pooled 12-month period prevalence of cancer in DVT only, PE only, and DVT + PE was 5.6% (95% CI, 4.4 to 7.2), 4.3% (95% CI, 2.7 to 6.9), and 5.6% (95% CI, 1.7 to 15.5), respectively. Most occult cancers were located in the abdomen (68.4%). The proportion of patients with an abdomino-pelvic cancer was not different in patients with DVT + PE (81%; 95% CI, 54 to 96) than in those with DVT (68%; 95% CI, 57 to 78) or PE alone (65%; 95% CI, 48 to 79).
The 12-month prevalence of occult cancer was similar in patients with DVT only, PE only, or both. Most cancers were located in the abdomen, and there was no relationship between VTE type and cancer location.
•The relationship between sites of VTE and occult cancer is unclear.•The 12-month prevalence of occult cancer was similar in DVT only, PE only, or both.•There were no relationship between unprovoked VTE and occult cancer locations.•Two thirds of cancers diagnosed after unprovoked VTE were located in the abdomen.
Pre- and posttreatment PET comparative scans should ideally be obtained with identical acquisition and processing, but this is often impractical. The degree to which differing protocols affect ...PERCIST classification is unclear. This study evaluates the consistency of PERCIST classification across different reconstruction algorithms and whether a proprietary software tool can harmonize SUV estimation sufficiently to provide consistent response classification.
Eighty-six patients with non-small cell lung cancer, colorectal liver metastases, or metastatic melanoma who were scanned for therapy monitoring purposes were prospectively recruited in this multicenter trial. Pre- and posttreatment PET scans were acquired in protocols compliant with the Society of Nuclear Medicine and Molecular Imaging and the European Association of Nuclear Medicine (EANM) acquisition guidelines and were reconstructed with a point spread function (PSF) or PSF + time-of-flight (TOF) for optimal tumor detection and also with standardized ordered-subset expectation maximization (OSEM) known to fulfill EANM harmonizing standards. After reconstruction, a proprietary software solution was applied to the PSF ± TOF data (PSF ± TOF.EQ) to harmonize SUVs with the OSEM values. The impact of differing reconstructions on PERCIST classification was evaluated.
For the OSEM
/OSEM
(OSEM reconstruction for pre- and posttherapeutic PET, respectively) scenario, which was taken as the reference standard, the change in SUL was -41% ± 25 and +56% ± 62 in the groups of tumors showing a decrease and an increase in
F-FDG uptake, respectively. The use of PSF reconstruction affected classification of tumor response. For example, taking the PSF ± TOF
/OSEM
scenario increased the apparent reduction in SUL in responding tumors (-48% ± 22) but reduced the apparent increase in SUL in progressing tumors (+37% ± 43), as compared with the OSEM
/OSEM
scenario. As a result, variation in reconstruction methodology (PSF ± TOF
/OSEM
or OSEM
/PSF ± TOF
) led to 13 of 86 (15%) and 17 of 86 (20%) PERCIST classification discordances, respectively. Agreement was better for these scenarios with application of the propriety filter, with κ values of 1 and 0.95 compared with 0.79 and 0.72, respectively.
Reconstruction algorithm-dependent variability in PERCIST classification is a significant issue but can be overcome by harmonizing SULs using a proprietary software tool.
In this work we determine conditions to produce cell samples for imaging with detection of the modification of the magnetic field by maghemite (Fe2O3) nanoparticles acting as a high sensitivity ...magnetic bio-sensor based on the giant magneto-impedance (GMI) effect. Mat Ly Lu cells are grown for 24 h with various maghemite nanoparticles concentrations (from 0 to 6 mg/ml). The percentage of viable cells is determined by counting labeled cells with trypan blue under an optical microscope. The quantity of nanoparticles internalized into the cells is evaluated by X-ray fluorescence analysis and expressed in iron moles per cell. The GMI bio-sensor was tested with the various samples. We observed that the best sensitivity of the GMI bio-sensor was obtained at a frequency of 1 MHz. To confirm these results in the presence of cell samples, four measurement frequencies were pre-selected (from 1 to 100 MHz) and tested. Cell growth conditions compatible with an acceptable percentage of cell viability for various concentrations of nanoparticles were also determined. These experiments allow us to conclude that cell growth with 0.1 mg/ml of nanoparticles for 24 h shows modifications of the magnetic field detectable optimally at 1 MHz frequency.
Abstract Objectives Smoking is the major risk factor for lung and head and neck cancer. The purpose of the present study was to determine the clinical impact of serendipitously revealed head and neck ...fixation on PET/CT in patients undergoing investigation for lung cancer. Material and methods The reports from PET/CT studies for patients with lung cancer from September 2005 and April 2012 were retrospectively reviewed. Head and neck incidentaloma was interpreted as suggestive of second primary malignancy. These incidental findings were compared with the final diagnosis obtained from clinical and histological investigation. Results Five hundred and ninety-two patients were investigated on PET/CT for lung cancer in the study period. PET/CT-positive head and neck lesions suggestive of second primary malignancy were found in 65 (11%) patients. Nasoendoscopy was performed in 23 patients and biopsy in 10. In 4 patients (17.4% of those explored), a second primary malignant lesion was proved on histology: 2 squamous cell carcinomas (larynx and oral cavity), 1 undifferentiated carcinoma (parotid), and 1 osteosarcoma (mandible). At a median 13 months’ follow-up, 3 of the 4 patients with a second primary had died from disease-related causes and 1 was free of recurrence. Metastases from lung adenocarcinoma were found in 2 patients (0.34%). Conclusions PET/CT detected incidental head and neck malignant tumors in at least 0.68% of lung cancer patients, but in 6.4% of those with suspect head and neck fixation.
Summary Objectives To set out good practice guidelines for locoregional extension assessment of squamous cell carcinoma of the head and neck (excluding nasopharynx, nasal cavities and sinuses). ...Materials and methods A critical multidisciplinary review of the literature on locoregional extension assessment of squamous cell carcinoma of the head and neck was conducted, applying levels of evidence in line with the French health authority's (HAS) literature analysis guide of January 2000. Conclusion Based on the levels of evidence of the selected articles and on work-group consensus, graded guidelines are set out for clinical, endoscopic and imaging locoregional extension assessment of head and neck cancer.
The aim of the present paper is to systematically review all available literature on preradiotherapy high uptake areas (hotspots) as a potential target for dose escalation in different tumour sites, ...and to understand the potential role and limitations of fluorodeoxyglucose (FDG)-positron-emission tomography (PET)/computed tomography (CT) in this context. An electronic database (Medline) search was conducted to identify articles reporting on a correlation between high tracer uptake on pretreatment PET and preferential sites of local recurrence after radiotherapy. Search was limited to English language. No date range limitation was applied. Among 45 studies initially identified, nine series matching with inclusion criteria have finally been retained from the literature after reviewing (5 retrospective and 4 prospective). Primary tumour locations were head-neck (n=2), lung (n=4), oesophageal (n=2) and rectal (n=1) areas. Overlaps between FDG hotspot on preradiotherapy PET/CT and site of local recurrence on post-treatment scan showed good to excellent agreement. Only studies on head-neck cancer reported moderate agreement probably explained by the lack of reproducibility of the patients positioning between pre- and post-treatment FDG-PET/CT; and by the rigid registration process of images limited by post-therapeutic changes that highly affect anatomical landmarks. FDG hotspot-guided radiotherapy may allow dose escalation in respecting a robust methodology (treatment position, co-registration method, four-dimensional PET).
L’objectif de cet article est de faire une revue systématique de toute la littérature disponible pour comprendre le rôle potentiel et les limites selon les localisations tumorales de la tomographie par émission de positons (TEP)-tomodensitométrie (TDM) au fluorodésoxyglucose (FDG) pour l’escalade de dose sur les zones de forte captation du traceur (points chauds ou « hotspots ») avant radiothérapie. Une recherche dans la base de données électronique (Medline) a été menée pour identifier les articles rapportant une corrélation entre les zones de forte captation du traceur à la TEP préthérapeutique et les sites préférentiels de récidive locale après radiothérapie. La recherche était limitée aux articles anglophones. Aucune limite de date de publication n’a été appliquée. Parmi les 45 études initialement identifiées, neuf séries correspondant aux critères d’inclusion ont finalement été retenues après lecture (cinq rétrospectives et quatre prospectives). La localisation tumorale primitive concernait les voies aérodigestives supérieures (n=2), les poumons (n=4), l’œsophage (n=2) et le rectum (n=1). Les intersections entre le hotspot de la TEP-TDM au fluorodésoxyglucose réalisée avant la radiothérapie et le site de récidive locale de l’examen après le traitement ont montré un accord bon à excellent. Seules les études menées sur le cancer des voies aérodigestives supérieures montraient un accord modéré, probablement expliqué par le manque de reproductibilité du positionnement des patients entre les TEP-TDM avant et après le traitement; et par la méthode rigide de recalage des images, limitée par les changements tissulaires post-thérapeutiques affectant fortement les repères anatomiques. La radiothérapie guidée par les hotspots sur la TEP-TDM au fluorodésoxyglucose peut permettre une augmentation de dose de radiothérapie en respectant une méthodologie robuste (position de traitement, méthode de coregistration, TEP quadridimensionnelle).
Screening for cancer in patients with unprovoked venous thromboembolism (VTE) often is considered, but clinicians need precise data on cancer prevalence, risk factors, and the effect of different ...types of screening strategies.
To estimate the prevalence of occult cancer in patients with unprovoked VTE, including in subgroups of different ages or those that have had different types of screening.
MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials up to 19 January 2016.
Prospective studies evaluating cancer screening strategies in adults with unprovoked VTE that began enrolling patients after 1 January 2000 and had at least 12 months of follow-up.
2 investigators independently reviewed abstracts and full-text articles and independently assessed risk of bias.
10 eligible studies were identified. Individual data were obtained for all 2316 patients. Mean age was 60 years; 58% of patients received extensive screening. The 12-month period prevalence of cancer after VTE diagnosis was 5.2% (95% CI, 4.1% to 6.5%). The point prevalence of cancer was higher in patients who had extensive screening than in those who had more limited screening initially (odds ratio OR, 2.0 CI, 1.2 to 3.4) but not at 12 months (OR, 1.4 CI, 0.89 to 2.1). Cancer prevalence increased linearly with age and was 7-fold higher in patients aged 50 years or older than in younger patients (OR, 7.1 CI, 3.1 to 16).
Variation in patient characteristics and extensive screening strategies; unavailability of long-term mortality data.
Occult cancer is detected in 1 in 20 patients within a year of receiving a diagnosis of unprovoked VTE. Older age is associated with a higher cancer prevalence. Although an extensive screening strategy initially may detect more cancer cases than limited screening, whether this translates into improved patient outcomes remains unclear.
None. (PROSPERO: CRD42016033371).
PDF
