The Role of 18F-FDG PET/CT in Guiding Precision Medicine for Invasive Bladder Carcinoma

International audienceBladder cancer (BC) is the 10th most common cancer worldwide. Approximately one quarter of patients with BC have muscle-invasive disease (MIBC). Muscle-invasive disease carries a poor prognosis and choosing the optimal treatment option is critical to improve patients’ outcomes. Ongoing research supports the role of 2-deoxy-2-(18F)fluoro-D-glucose positron emission tomography (18F-FDG PET) in guiding patient-specific management decisions throughout the course of MIBC. As an imaging modality, 18F-FDG PET is acquired simultaneously with either computed tomography (CT) or MRI to offer a hybrid approach combining anatomical and metabolic information that complement each other. At initial staging, 18F-FDG PET/CT enhances the detection of extravesical disease, particularly in patients classified as oligometastatic by conventional imaging. 18F-FDG PET/CT has value in monitoring response to neoadjuvant and systemic chemotherapy, as well as in localizing relapse after treatment. In the new era of immunotherapy, 18F-FDG PET/CT may also be useful to monitor treatment efficacy as well as to detect immune-related adverse events. With the advent of artificial intelligence techniques such as radiomics and deep learning, these hybrid medical images can be mined for quantitative data, providing incremental value over current standard-of-care clinical and biological data. This approach has the potential to produce a major paradigm shift toward data-driven precision medicine with the ultimate goal of personalized medicine. In this review, we highlight current literature reporting the role of 18F-FDG PET in supporting personalized management decisions for patients with MIBC. Specific topics reviewed include the incremental value of 18F-FDG PET in prognostication, pre-operative planning, response assessment, prediction of recurrence, and diagnosing drug toxicity

Data products for fish stocks and ecosystem assessment:the PELGAS survey example

The initial objective of the PELGAS integrated survey was to assess the biomass of small pelagic fish in the Bay of Biscay in spring. Sampling has been extended to study the spatial structure and dynamics of the pelagic ecosystem in springtime. The PELGAS survey has produced since 2000 long-term time-series of spatially-explicit data and indices, describing the main pelagic ecosystem components: hydrology, phytoplankton, mesozooplankton, fish and megafauna. In addition to small pelagic fish biomass estimates used for fish stock assessment, the survey now delivers two types of ecosystem products: standard gridded maps of ecosystem parameters, and a time series dataset of indicators of the Bay of Biscay pelagic ecosystem state. The evolution of the PELGAS survey and sampling sampling designs are presented and discussed, to highlight their impact on the survey ecosystem products. The potential of PELGAS survey products for ecosystem assessment is demonstrated with two case studies. Series of multivariate maps are first analysed to assess the pelagic ecosystem spatial structure. A map of consistent ecosystem seascapes boundaries and of their inter-annual variability in time is presented. Second, time series of potential ecosystem indices derived from the survey are jointly analysed to select the most continuous indicators within, and across, several ecosystem components. Trends in the selected time series are interpreted to derive information on marine ecosystem status and dynamics. Challenges and future directions are discussed, with a focus on the new big data flows that could be provided by the survey in a near future

Fifteen years of data from the PELGAS integrated survey (2000-2015): what have we learned on the Bay of Biscay pelagic ecosystem?

The initial focus of the PELGAS integrated survey was to assess the small pelagic fish biomass in the Bay of Biscay in springtime, for fisheries management purposes. Sampling has been extended to produce long-term time-series of spatially-explicit data and indices, describing the main pelagic ecosystem components: hydrology, phytoplankton, mesozooplankton, fish and megafauna. A collaborative analysis of these datasets has brought new insights on the Bay of Biscay pelagic ecosystem summarized here. New results on single ecosystem components include an analysis of water samples to groundtruth the results of an ocean color algorithm aiming at detecting phytoplanktonic coccolithophores. New insights on mesozooplankton spatio-temporal distribution and energy content have been derived from the analysis of net samples. Adult anchovy and sardine energy content have been studied along a latitudinal gradient, and across different age stages. Changing patterns in the relative abundance of marine megafauna have been evidenced at a community level. Cross-ecosystem component studies are also presented. Actual dates of the annual survey have been corrected, with respect to a surface temperature climatology, allowing for an improved interpretation of anchovy and sardine spawning. Spring habitats of small pelagic fish communities in the Bay of Biscay have been characterised. Fluctuations in habitat preferences of five mobile top predators species have been assessed. Predation of cetaceans on small pelagic fish has been investigated, based on stomach contents. The spatial structure of the ecosystem has been characterised, to map consistent ecosystem seascapes and study their variability in time. Dominant ecological processes in the Bay of Biscay have been identified based on series of potential pelagic ecosystem indicators derived from the survey, and the effects of external forcing on the ecosystem dynamics tested. Perspectives for the survey are discussed in the context of the European Marine Strategy Framework Directive and the Common Fisheries Policy

The PELGAS survey: ship-based integrated monitoring of the Bay of Biscay pelagic ecosystem

The Pélagiques Gascogne (PELGAS) integrated survey has been developed by a multidisciplinary team of Ifremer and La Rochelle University scientists since 2000, joined by commercial fishermen in 2007. Its initial focus was to assess the biomass and predict the recruitment success of anchovy in the Bay of Biscay in spring. Taking advantage of the space and versatility of R/V Thalassa II, sampling has been progressively extended to other ecosystem components. PELGAS therefore further developed the second objective of monitoring and studying the dynamic and diverse Biscay pelagic ecosystem in springtime. The PELGAS survey model has allowed for the establishment of a long-term time-series of spatially-explicit data of the Bay of Biscay pelagic ecosystem since the year 2000. Main sampled components of the targeted ecosystem are: hydrology, phytoplankton, mesozooplankton, fish and megafauna. The survey now provides two main ecosystem products: standard raster maps of ecosystem parameters, and a time series dataset of indicators of the Bay of Biscay pelagic ecosystem state. They are used to inform fish stock and ecosystem-based management, and support ecosystem research. The present paper introduces the PELGAS survey, as a practical example of an integrated, vessel-based, ecosystem survey. The evolution of the PELGAS scientific team and sampling protocols are presented and analysed, to outline factors crucial to the success of the survey. Data and results derived from PELGAS are reviewed, to exemplify scientific questions that can be tackled by integrated ecosystem survey data. Advantages and challenges of the survey are discussed and put into the context of marine ecosystem surveys in the European Marine Strategy Framework Directive and the Common Fisheries Policy.