Radiomics for precision medicine: Current challenges, future prospects, and the proposal of a new framework.

The advancement of artificial intelligence concurrent with the development of medical imaging techniques provided a unique opportunity to turn medical imaging from mostly qualitative, to further quantitative and mineable data that can be explored for the development of clinical decision support systems (cDSS). Radiomics, a method for the high throughput extraction of hand-crafted features from medical images, and deep learning -the data driven modeling techniques based on the principles of simplified brain neuron interactions, are the most researched quantitative imaging techniques. Many studies reported on the potential of such techniques in the context of cDSS. Such techniques could be highly appealing due to the reuse of existing data, automation of clinical workflows, minimal invasiveness, three-dimensional volumetric characterization, and the promise of high accuracy and reproducibility of results and cost-effectiveness. Nevertheless, there are several challenges that quantitative imaging techniques face, and need to be addressed before the translation to clinical use. These challenges include, but are not limited to, the explainability of the models, the reproducibility of the quantitative imaging features, and their sensitivity to variations in image acquisition and reconstruction parameters. In this narrative review, we report on the status of quantitative medical image analysis using radiomics and deep learning, the challenges the field is facing, propose a framework for robust radiomics analysis, and discuss future prospects.

[Comparative analysis of the brain distribution of [18F]FDG in populations of patients with Alzheimer's disease with or without family history of dementia]. / Analyse comparative de la distribution cérébrale du [18F]FDG dans une population de patients souffrant de maladie d'Alzheimer présentant ou non des antécédents familiaux de démence.

Hereditary forms of Alzheimer's disease (AD) and early-onset forms have more brain damage than sporadic or late-onset forms at the time of diagnosis (1, 2). Data in the literature are contradictory concerning familial forms without known heredity or mutation. The aim of this study was to compare the brain distribution of FDG between two populations of patients with a clinical diagnosis of sporadic AD according to the presence or not of a first degree family history of dementia. We retrospectively included 243 patients with clinical diagnosis of AD who underwent brain FDG PET imaging between 2012 and 2017. SPM12 was used to compare the FDG brain distribution in 199 patients with AD and no familial history of dementia and 43 patients with AD and first degree familial history of dementia. Compared to a database of 22 healthy control subjects, both groups of AD patients showed a significant decrease of FDG distribution in temporo-parietal, posterior cingulate and posterior left frontal cortex with respect to the controls (p inferior to 0.05 corrected for the family-wise error, pFWE-corr). There were no significant differences between the two AD groups (pFWE-corr superior to 0.05 and p superior to 0.001 uncorrected for multiple comparisons) that present the same brain metabolic pathology.

Les formes héréditaires de la maladie d'Alzheimer (MA) et les formes à début précoce présentent une atteinte cérébrale plus importante que les formes sporadiques ou celles à début tardif au moment du diagnostic (1, 2). Les données de la littérature sont contradictoires en ce qui concerne les formes familiales sans hérédité ni mutation connue. L'objectif de cette étude était de comparer la distribution cérébrale du [18F]fluoro-2-deoxy-D-glucose ([18F]FDG) entre deux populations de patients présentant un diagnostic clinique de la MA sporadique selon la présence, ou non, d'une histoire familiale de démence au premier degré. Dans cette étude rétrospective, nous avons inclus 243 patients vus entre 2012 et 2017. Le logiciel SPM12 a été utilisé pour comparer la distribution cérébrale du FDG entre 199 patients souffrant de MA, sans histoire familiale et 43 patients souffrant de MA avec une histoire familiale de démence au premier degré. Comparés à une base de données de 22 sujets contrôles sains, chacun des deux groupes de patients présentait une réduction significative de la distribution du FDG au niveau du cortex temporo-pariétal, cingulaire postérieur et frontal postérieur gauche (p inf�rieur a 0,05 corrigé pour le family-wise error, pFWE-corr), caractéristique de la maladie. Il n'y avait pas de différence significative entre les deux groupes MA (pFWE-corr sup�rieur a 0,05 et p sup�rieur a 0,001 non corrigé, pour des comparaisons multiples) qui présentent donc la même altération métabolique cérébrale.

[18F]FDG PET/CT imaging disproves renal allograft acute rejection in kidney transplant recipients with acute kidney dysfunction: a validation cohort.

PURPOSE: [18F]FDG PET/CT may predict the absence of acute allograft rejection (AR) in kidney transplant recipients (KTRs) with acute kidney injury (AKI). Still, the proposed threshold of 1.6 of the mean of mean standardized uptake values (mSUVmean) in the renal parenchyma needs validation. METHODS: We prospectively performed 86 [18F]FDG PET/CT in 79 adult KTRs who underwent per-cause transplant biopsy for suspected AR. Biopsy-proven polyoma BK nephropathies (n = 7) were excluded. PET/CT was performed 192 ± 18 min after administration of 254.4 ± 30.4 MBq of [18F]FDG. The SUVmean was measured in both upper and lower poles of the renal allograft. One-way analysis of variance (ANOVA) and Tukey's studentized range test were sequentially performed. The receiver operating characteristic (ROC) curve was drawn to discriminate "AR" from non-pathological ("normal" + "borderline") conditions. RESULTS: The median age of the cohort was 55 [43; 63] years, with M/F gender ratio of 47/39. The mean eGFR was 31.9 ± 14.6 ml/min/1.73m2. Biopsies were categorized in 4 groups: "normal" (n = 54), "borderline" (n = 9), "AR" (n = 14), or "others" (n = 2). The median [min; max] mSUVmean reached 1.72 [1.02; 2.07], 1.97 [1.55; 2.11], 2.13 [1.65, 3.12], and 1.84 [1.57; 2.12] in "normal," "borderline," "AR," and "others" groups, respectively. ANOVA demonstrated a significant difference of mSUVmean among groups (F = 13.25, p < 0.0001). The ROC area under the curve was 0.86. Test sensitivity and specificity corresponding to the threshold value of 1.6 were 100% and 30%, respectively. CONCLUSION: [18F]FDG PET/CT may help noninvasively prevent inessential transplant biopsies in KTR with AKI.

[Concepts of medical imaging in the work up and follow-up of cancer : oncological imaging at a glance]. / Concepts d'imagerie médicale dans la mise au point et le suivi des cancers : regard sur l'imagerie oncologique.

Oncological imaging is a subspecialty of medical imaging and focuses on the workup and the follow-up of cancer. Oncological imaging takes into account all the specificities of cancer diseases, which is a constantly evolving field, especially in the era of precision medicine, and plays a key role in the care of cancer patients. It permits reliable diagnosis and gives precious information concerning disease extension at diagnosis, which is essential for the treatment planning. Oncological imaging allows also followup of patients under treatment, using response evaluation scores. Interventional imaging, which provides minimally invasive procedures, is useful in order to obtain a histological diagnosis, to treat some tumour or to improve quality of life of cancer patients. Finally, numerous perspectives, among them the advent of artificial intelligence (radiomics), will further strengthen the role of oncologic imaging in the near future.

L'imagerie oncologique, qui est une sous-discipline de l'imagerie médicale, s'intéresse spécifiquement à la mise au point et au suivi des cancers. Elle prend en compte toutes les spécificités de la maladie oncologique, dont les traitements évoluent constamment à l'ère de la médecine de précision. Elle joue un rôle primordial à toutes les étapes du trajet de soin du patient. Elle permet la réalisation de diagnostics fiables et donne des informations sur l'étendue de la maladie au moment du diagnostic, nécessaires à l'établissement d'un plan de traitement. L'imagerie oncologique s'intéresse également au suivi des patients sous traitement, grâce notamment à l'utilisation de score d'évaluation de la réponse thérapeutique. L'imagerie interventionnelle, à travers la réalisation de procédures faiblement invasives, joue un rôle dans l'obtention du diagnostic, dans le traitement de certaines tumeurs ou dans l'amélioration de la qualité de vie du patient. Enfin, de nombreuses perspectives, et notamment l'avènement de l'intelligence artificielle (radiomique), ne vont faire que renforcer le rôle central de l'imagerie oncologique dans les prochaines années.

[Multidisciplinary management of alveolar echinococcosis : Echino-Liege Working Group]. / Prise en charge multidisciplinaire de l'échinococcose alvéolaire : le groupe Echino-Liège.

Alveolar echinococcosis is a zoonotic disease due to the tapeworm Echinococcus multilocularis. The definitive host is the red fox. Until recently, Belgium was considered a country at very low risk for alveolar echinococcosis. However, recent studies carried out in southern Belgium have revealed, through post-mortem examination, high prevalences (up to 62 %) in foxes. Cats and dogs can act as definitive hosts. Human are accidentally infected by ingestion of food contaminated by the feces. After a long incubation period, invasive hepatic lesions may appear, as well as extra-hepatic lesions. The disease may be fatal. The diagnosis is based on imaging techniques, serology and nucleic acid detection in tissues. Early diagnosis may allow surgical removal of the lesion associated with at least 2 years of albendazole postoperative treatment. In case of contraindication to surgery, a long term treatment with albendazole is necessary. Liver transplantation is sometimes necessary. This article presents the epidemiologic, clinical, diagnostic and therapeutics features of this zoonotic disease.

L'échinococcose alvéolaire est une zoonose due à Echinococcus multilocaris, un cestode, dont l'hôte définitif est le renard roux (Vulpes vulpes). Jusqu'il y a peu, la Belgique était un pays considéré comme à très faible risque pour cette parasitose, mais de récentes autopsies de renards ont montré des prévalences élevées chez ceux-ci (pouvant dépasser les 60 %). Les chiens et les chats peuvent également être des hôtes définitifs. La transmission humaine (hôte accidentel) se fait principalement via la consommation d'aliments souillés par les déjections animales contaminées donnant, après une longue période d'incubation, des lésions hépatiques infiltrantes et, éventuellement, des atteintes extra-hépatiques pouvant être mortelles. Le diagnostic est fondé sur l'imagerie médicale couplée à des tests sérologiques et la PCR sur des tissus. La prise en charge curative est chirurgicale, lorsque la résection complète est possible. Elle est associée à un traitement de deux ans post-opératoire à base d'albendazole. En cas d'impossibilité de résection complète, un traitement au long cours par de l'albendazole est préconisé. Enfin, dans certains cas, une transplantation hépatique peut être envisagée. En raison de l'augmentation des cas autochtones rencontrés en Wallonie, un groupe spécialisé dans la prise en charge de l'échinococcose a été créé au sein de l'université de Liège. Cet article illustre les caractéristiques épidémiologiques, cliniques, diagnostiques et thérapeutiques de cette zoonose.

Fluorodeoxyglucose F(18) Positron Emission Tomography Coupled With Computed Tomography in Suspected Acute Renal Allograft Rejection.

Management of kidney transplant recipients (KTRs) with suspected acute rejection (AR) ultimately relies on kidney biopsy; however, noninvasive tests predicting nonrejection would help avoid unnecessary biopsy. AR involves recruitment of leukocytes avid for fluorodeoxyglucose F(18) ((18) F-FDG), thus (18) F-FDG positron emission tomography (PET) coupled with computed tomography (CT) may noninvasively distinguish nonrejection from AR. From January 2013 to February 2015, we prospectively performed 32 (18) F-FDG PET/CT scans in 31 adult KTRs with suspected AR who underwent transplant biopsy. Biopsies were categorized into four groups: normal (n = 8), borderline (n = 10), AR (n = 8), or other (n = 6, including 3 with polyoma BK nephropathy). Estimated GFR was comparable in all groups. PET/CT was performed 201 ± 18 minutes after administration of 3.2 ± 0.2 MBq/kg of (18) F-FDG, before any immunosuppression change. Mean standard uptake values (SUVs) of both upper and lower renal poles were measured. Mean SUVs reached 1.5 ± 0.2, 1.6 ± 0.3, 2.9 ± 0.8, and 2.2 ± 1.2 for the normal, borderline, AR, and other groups, respectively. One-way analysis of variance demonstrated a significant difference of mean SUVs among groups. A positive correlation between mean SUV and acute composite Banff score was found, with r(2) = 0.49. The area under the receiver operating characteristic curve was 0.93, with 100% sensitivity and 50% specificity using a mean SUV threshold of 1.6. In conclusion, (18) F-FDG PET/CT may help noninvasively prevent avoidable transplant biopsies in KTRs with suspected AR.

Prognostic value of baseline total metabolic tumor volume (TMTV0) measured on FDG-PET/CT in patients with peripheral T-cell lymphoma (PTCL).

BACKGROUND: Most peripheral T-cell lymphoma (PTCL) patients have a poor outcome and the identification of prognostic factors at diagnosis is needed. PATIENTS AND METHODS: The prognostic impact of total metabolic tumor volume (TMTV0), measured on baseline [(18)F]2-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography, was evaluated in a retrospective study including 108 PTCL patients (27 PTCL not otherwise specified, 43 angioimmunoblastic T-cell lymphomas and 38 anaplastic large-cell lymphomas). All received anthracycline-based chemotherapy. TMTV0 was computed with the 41% maximum standardized uptake value threshold method and an optimal cut-off point for binary outcomes was determined and compared with others prognostic factors. RESULTS: With a median follow-up of 23 months, 2-year progression-free survival (PFS) was 49% and 2-year overall survival (OS) was 67%. High TMTV0 was significantly associated with a worse prognosis. At 2 years, PFS was 26% in patients with a high TMTV0 (>230 cm(3), n = 53) versus 71% for those with a low TMTV0, [P < 0.0001, hazard ratio (HR) = 4], whereas OS was 50% versus 80%, respectively, (P = 0.0005, HR = 3.1). In multivariate analysis, TMTV0 was the only significant independent parameter for both PFS and OS. TMTV0, combined with PIT, discriminated even better than TMTV0 alone, patients with an adverse outcome (TMTV0 >230 cm(3) and PIT >1, n = 33,) from those with good prognosis (TMTV0 ≤230 cm(3) and PIT ≤1, n = 40): 19% versus 73% 2-year PFS (P < 0.0001) and 43% versus 81% 2-year OS, respectively (P = 0.0002). Thirty-one patients (other TMTV0-PIT combinations) had an intermediate outcome, 50% 2-year PFS and 68% 2-year OS. CONCLUSION: TMTV0 appears as an independent predictor of PTCL outcome. Combined with PIT, it could identify different risk categories at diagnosis and warrants further validation as a prognostic marker.

Function-structure connectivity in patients with severe brain injury as measured by MRI-DWI and FDG-PET.

A vast body of literature exists showing functional and structural dysfunction within the brains of patients with disorders of consciousness. However, the function (fluorodeoxyglucose FDG-PET metabolism)-structure (MRI-diffusion-weighted images; DWI) relationship and how it is affected in severely brain injured patients remains ill-defined. FDG-PET and MRI-DWI in 25 severely brain injured patients (19 Disorders of Consciousness of which 7 unresponsive wakefulness syndrome, 12 minimally conscious; 6 emergence from minimally conscious state) and 25 healthy control subjects were acquired here. Default mode network (DMN) function-structure connectivity was assessed by fractional anisotropy (FA) and metabolic standardized uptake value (SUV). As expected, a profound decline in regional metabolism and white matter integrity was found in patients as compared with healthy subjects. Furthermore, a function-structure relationship was present in brain-damaged patients between functional metabolism of inferior-parietal, precuneus, and frontal regions and structural integrity of the frontal-inferiorparietal, precuneus-inferiorparietal, thalamo-inferioparietal, and thalamofrontal tracts. When focusing on patients, a stronger relationship between structural integrity of thalamo-inferiorparietal tracts and thalamic metabolism in patients who have emerged from the minimally conscious state as compared with patients with disorders of consciousness was found. The latter finding was in line with the mesocircuit hypothesis for the emergence of consciousness. The findings showed a positive function-structure relationship within most regions of the DMN. Hum Brain Mapp 37:3707-3720, 2016. © 2016 Wiley Periodicals, Inc.

[18F-FPRGD2 PET/CT imaging of integrin αVß3]. / Imagerie de l'intégrine αVß3 par PET/CT au 18F-FPRGD2.

PET/CT imaging of 15F-FPRGD2 allows the visualization and quantification of integrin αVß3 in tissues. This imaging technique was developed with the purpose of quantifying tumor angiogenesis and of assessing the efficacy of antiangiogenic treatments. However, the PET signal of 18F-FPRGD2 appears more complex as various tumor cell types, inflammatory cells and osteoclasts express the integrin αVß3 regulating cell interactions with the extracellular matrix. This article provides data of clinical studies evaluating 18F-FPRGD2 PET/CT imaging in patients with a renal mass or a locally advanced rectal carcinoma and finally reports on the incidental discovery of 18F-FPRGD2 uptake in osteoarticular processes such as osteoarthritis.

[Benefits of positron emission tomography in the management and prognosis of abdominal aortic aneurysms]. / Intérêts de la tomographie à éimission de positons dans le suivi et le pronostic des anévrysmes de l'aorte abdominale.

Rupture of abdominal aortic aneurysm (AAA) remains a major cause of death in the elderly. Its prediction is a serious challenge for public health. Despite its regular use to identify patients requiring surgical treatment, the diameter of AAA is not a sufficiently precise and reliable parameter for discriminating aneurysms at high risk of rupture. A better targeting of high risk patients needs understanding in deep the processes and mechanisms directing wall rupture. Inflammation is a significant element in the progression ofAAA and can be visualized using medical imaging techniques such as positron emission tomography (PET) using a glucose derivative (FDG) as radiotracer. Studies conducted in our department have established a relationship between PET positivity and the presence of symptoms such as accelerated growth of the aneurysm or pain, signs generally considered as predictive of rupture. Moreover, activation of leukocytes coupled to cellular and molecular alterations of the aneurysmal wall in the sites of FDG uptake may lead to its instability and incompetence to resist blood pressure and rupture. PET therefore represents a new original exploration method to characterize the severity of AAA progression allowing to assess the need for a surgical treatment much better than does the AAA diameter.

[Functional imaging and radiotherapy]. / Utilisation de l'imagerie fonctionnelle en radiothérapie.

Medical imaging plays a crucial role in the diagnosis, staging and therapeutic strategy of oncologic patients. The development of medical imaging over the last decade has allowed significant progresses in radiotherapy. Indeed, medical imaging is now considered the corner stone of radiotherapy. The main challenge for the radiation oncologist consists in the tumour identification with a view to irradiate the tumour at a curative dose while avoiding healthy tissues. To achieve these goals, the radiotherapist daily uses anatomical imaging such as computed tomography (CT) or magnetic resonance imaging (MRI). Since several years now, the development of functional imaging such as positron emission tomography (PET) combined with CT or functional MRI has opened new perspectives in the management of oncologic diseases. Indeed, these imaging techniques offer new information on tumour metabolism that may be taken into account to plan the radiotherapy treatment. This article illustrates the different imaging techniques used in radiotherapy and the role of functional imaging for establishing new therapeutic strategies in radiation oncology.

Radiotherapy modification based on artificial intelligence and radiomics applied to (18F)-fluorodeoxyglucose positron emission tomography/computed tomography.

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.

The reliability of transcranial duplex scanning in parkinsonian patients: comparison of different observers and ultrasound systems.

PURPOSE: To establish the inter-observer and intra-transducer reliability of "on-line" and "off-line" assessment of substantia nigra (SN) and raphe nuclei (RN) by transcranial duplex scanning (TCD) in a mixed study population. MATERIALS AND METHODS: Out-patient neurology department of the University Hospital Maastricht. In total 24 subjects were investigated: 9 patients with idiopathic Parkinson's disease, 10 with parkinsonism from yet unclear origin, 1 with essential tremor and 4 healthy volunteers. Each patient was assessed four times by two independent experienced sonographers using two different ultrasound devices: SONOS 5500 and iU22; both Philips, Eindhoven, The Netherlands. The echointensity of the SN is evaluated qualitatively and quantitatively and the RN only qualitatively. 1. In the "on-line" assessment we determined: a) the inter-observer agreement of the four possible combinations. b) the intra-observer agreement of both sonographers using two different ultrasound systems. 2. In the "off-line" assessment a third sonographer re-examined the stored images. We determined the inter-observer agreement of the third sonographer with the "on-line" assessment of the other two sonographers. Cohen's k value was calculated for the agreement. RESULTS: 1a) The "on-line" inter-observer agreement of the four possible combinations of sonographer and transducer was: kappa 0.23 - 0.39 for the qualitative evaluation of the SN, kappa 0.31 - 0.56 for the quantitative evaluation of the SN and kappa 0.03 - 0.15 for the evaluation of the RN. 1b) The "on-line" intra-observer agreement was: kappa 0.53 - 0.67 for the qualitative evaluation of the SN, kappa 0.55 - 0.76 for the quantitative evaluation of the SN and kappa 0.45 - 0.47 for the evaluation of the RN. 2. The "off-line" inter-observer agreement was: kappa 0.32 - 0.67 for the qualitative evaluation of the SN, kappa 0.53 - 0.61 for the quantitative evaluation of the SN and kappa 0.08 - 0.33 for the evaluation of the RN. CONCLUSION: For the SN we found mediocre accordance comparing both observers "on-line" with each other as well as comparing an "off-line" observer with both "on-line" observers. On the whole, the inter-observer and intra-observer agreement were moderate to substantial for the evaluation of the SN. "On-line" and "off-line" comparisons yielded comparable results. The agreement for the evaluation of the RN, on the contrary, was considerably lower. Our findings indicate that this TCD technique is not yet ready for the application in large population screenings.

[Imaging bone metastases in breast cancer]. / Imagerie des métastases osseuses du cancer du sein.

Breast cancer is the most common female malignancy and bone is the most common site of distant metastases. Early detection and accurate assessment of bone involvement is needed to optimize treatment and therefore reduce or delay skeletal-related events. We discuss the different bone imaging modalities with emphasis on nuclear medicine techniques. Currently, whole body bone scintigraphy (BS) is recommended in selected patients at high risk of bone metastases (BM). New hybrid cameras combining 3-D scintigraphic images and computed tomography (SPECT/CT) improve diagnostic accuracy of BS. The 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET) seems to exhibit higher specificity and accuracy to detect BM in breast cancer. FDG PET/CT could be a useful tool for monitoring the effectiveness of treatment of breast cancer BM. Recent whole-body magnetic resonance imaging (MRI) techniques could become an additional tool to assess bone involvement from breast cancer. No consensus has been yet established regarding the best modality for diagnosing breast cancer BM and for assessing its response to treatment. The best approach is probably the combination of the different imaging modalities knowing the strengths and weaknesses of each technique.

[Heterogeneity of bone metastases in a patient with breast cancer: case report illustrating the potential of combining various imaging techniques]. / Hétérogénéité des métastases osseuses du cancer du sein: cas clinique illustrant l'intérêt de combiner différentes techniques d'imagerie.

Morphological appearance of bone metastases in breast cancer can be classified into three groups: osteolytic, sclerotic and mixed types. 18F-NaF PET/CT is considered to be superior to bone scintigraphy (BS) for the detection of bone metastases. 18F-NaF PET shows a higher uptake in both lytic and sclerotic bone metastases with a higher contrast and spatial resolution than BS. 18F-FDG PET is generally considered to be superior to BS for detection of lytic bone metastases. However, BS and 18F-NaF PET/CT are more sensitive for sclerotic lesions, as a decreased 18F-FDG uptake in this subtype of lesion has been reported. In conclusion, as various types of bone metastases may coexist in a single patient, the combination of both 18F-FDG and 18F-fluoride PET/CT studies is likely to provide the most comprehensive assessment of metastatic spread to the skeleton.

[Sentinel lymph node biopsy and axillary reverse mapping: a tailoring axillary staging in breast cancer]. / Ganglion sentinelle et sentibras: pour un "staging" axillaire sur mesure.

The status of the axillary lymph nodes is one of the most important prognostic factors in women with early stage breast cancer. Histologic examination of removed lymph nodes is the most accurate method for assessing spread of disease to these nodes. Axillary lymph node dissection (ALND) remains the standard approach for women who have clinically palpable axillary nodes. The benefits of ALND include its impact on disease control (axillary recurrence and survival), its prognostic value, and its role in treatment selection. However, the anatomic disruption caused by ALND may result in lymphedema, nerve injury, and shoulder dysfunction, which compromise functionality and quality of life. For patients who have clinically negative axillary lymph nodes, sentinel lymph node (SLN) biopsy offers a less morbid method to determine if there are positive nodes, in which case axillary node dissection would be necessary. Patients who are SLN-positive should undergo complete ALND. Axillary reverse mapping (ARM) is a recent improvement of ALND which, like the biopsy of the GS, would reduce morbidity.

[Hypophosphatemia and tumor-induced osteomalacia]. / Hypophosphatémie et ostéomalacie oncogénique.

In this article, we will discuss about hypophosphatemia due to tumor-induced osteomalacia. This disease is characterized by severe muscular and articular tenderness inducing profound walking limitation. Clinical chemistry results show severe hypophosphatemia due to hyperphosphaturia. Fibroblast growth factor 23 (FGF-23) is abnormally high. Physiological role of FGF-23 is examined. We also consider the pathophysiology of tumor induced osteomalacia, the use of different investigations to localize the tumor and therapies available to treat this rare disease.

[Image guided stereotactic treatment with CyberKnife yields surgical precision]. / Vers une radiothérapie chirurgicale: nécessité d'une radiothérapie guidée par l'imagerie.

The field of radiation oncology is rapidly evolving especially thanks to the tremendous progress in robotics and computer sciences. One of the consequences is the implementation of a technique like the CyberKnife. This particular radiation therapy modality allows the use of "ablative" radiation doses, a concept which is not even conceivable with conventional approaches. This has been made possible by major changes in the ways target and margins around are defined and the way radiation therapy is fractionated. The result of these changes is for some tumours a doubling of the radiobiological effect of the ionizing irradiation. In order to cover the target with the highest possible conformality, without harming surrounding healthy tissues, optimized definition of the target is key. It is not only important to get information on the extent of the target with the highest possible resolution, but it is also important to assess the content, i.e., metabolic heterogeneity. The developments made in the field of diagnostic and functional radiology and nuclear medicine do allow to take advantage of the numerical information to individualize and adapt treatment prescription, even consider modification throughout the course of irradiation.

[Monoclonal antibodies in hematology in 2009]. / Les anticorps monoclonaux en hématologie en 2009.

Directed against the CD20 antigen on B lymphocytes, rituximab (MabThera) is now incorporated in the first line therapy of symptomatic follicular as well as diffuse large B cell non-Hodgkin's lymphoma and offers superior response and survival rates. 90Y ibritumomab tiuxetan (Zevalin) combines the specificity of rituximab for the CD20 antigen and the therapeutic effect of beta irradiation. Given in monotherapy, it constitutes an interesting alternative therapy for follicular lymphomas in second relapse. Alemtuzumab (MabCampath) recognizes the CD52 antigen and offers encouraging results in chronic lymphocytic leukemia resistant to classical chemotherapy.