Search

Resume L’annonce et la communication des resultats d’un examen de medecine nucleaire au patient, notamment en TEP, relevent de pratiques tres differentes d’un service a l’autre ou d’un praticien a l’autre. Or, la reglementation relative a l’information des patients et a l’acces a leurs donnees de sante ainsi que les recommandations de l’Institut national du cancer concernant l’evolution du dispositif d’annonce d’un cancer plaident pour une plus grande implication des medecins imageurs, radiologues et medecins nucleaires dans le processus d’annonce. Au-dela des considerations legales, il apparait ethiquement et humainement difficile de refuser toute forme de communication medicale au patient qui en fait la demande et le laisser decouvrir seul son resultat sans commentaire ou echange avec le medecin specialiste ayant redige le compte-rendu. Cependant, l’heterogeneite des pratiques au sein de la communaute de medecine nucleaire est reelle et se doit d’etre comprise. Les principaux arguments des medecins ne realisant pas d’annonce sont analyses et des pistes sont evoquees pour tenter de repondre, concretement et de maniere non dogmatique, a l’attente legitime de nombreux patients.

Resume Introduction L’objectif de notre etude etait d’evaluer l’impact d’une acquisition TEP/TDM synchronisee a la respiration (methode « multi-phases ») sur la detectabilite et la quantification de lesions hepatiques. Patients et methodes Vingt-et-un patients adresses pour TEP au 18 F- fluorodesoxyglucose (FDG) et ayant des lesions hepatiques secondaires connues ou suspectees ont ete inclus prospectivement. La TEP/TDM 3D etait suivie d’une acquisition TEP/TDM 4D (6 phases de 2 minutes). La detectabilite et les parametres quantitatifs suivants ont ete compares sur les deux acquisitions : SUV max des lesions (SUVmax L ), SUV max et SUV mean du foie sain (SUVmax F et SUVmean F ), rapport SUVmax L /SUVmean F (RLF), volume metabolique (MTV) et TLG des lesions. Resultats Quinze des 21 patients presentaient 63 lesions hepatiques sur la base du suivi par TDM ou IRM (13 patients) et des resultats anatomopathologiques apres chirurgie (2 patients). Par patient, la TEP 4D n’ameliorait pas la sensibilite deja elevee de la TEP 3D (93 %). Les gains en sensibilite par lesion avec la TEP/TDM 4D (84 vs 80 %) n’etaient pas statistiquement significatifs, y compris dans le sous-groupe des lesions infracentimetriques. La TEP 4D apportait un meilleur contraste via la diminution significative des SUVmean F (−10 %), SUVmax F (−16 %) et ecarts-types de SUV (−35 %) et l’augmentation non significative des RLF (+19 % ; p = 0,07). La correction d’attenuation par la TDM 4D ne modifiait pas les valeurs de SUVmax L , y compris ceux proches du diaphragme. Conclusion L’apport d’une acquisition TEP/TDM 4D multiphases parait limite pour le diagnostic des lesions hepatiques, meme si un gain en sensibilite semble exister pour les lesions infracentimetriques, grâce a un meilleur contraste lesionnel. L’utilisation de la TDM standard pour la correction d’attenuation, equivalente a la TDM 4D, parait de ce fait legitime pour ne pas augmenter l’irradiation des patients.

Posttransplantation lymphoproliferative disorders (PTLDs) are life-threatening complications after solid organ and hematopoietic stem cell transplantation. Only half of CD20-positive PTLDs respond to rituximab monotherapy, and outcomes remain poor for patients with relapsed/refractory disease, especially those who do not qualify for an anthracycline containing regimen due to frailty or comorbidities. Radioimmunotherapy (RIT) might be an option in this particular setting. We report a panel of eight patients with rituximab refractory/relapsed CD20-positive PTLDs including three ineligible for subsequent CHOP-like chemotherapy who received (90) Y-Ibritumomab tiuxetan as a single agent (n = 7) or combined to chemotherapy (n = 1). Five out of eight patients were kidney transplant recipients, while 2/8 had a liver transplant and 1/8 had a heart transplant. Patients received a median of two previous therapies. Overall response rate was 62.5%. Importantly, all responders achieved complete response. At a median follow-up of 37 months [5; 84], complete response was ongoing in four patients. Toxicity was predominantly hematological and easily manageable. No graft rejection was noticed concomitantly or following RIT administration despite immunosuppression reduction after diagnosis of PTLDs. This report emphasizes the potential efficiency of salvage RIT for early rituximab refractory PTLDs without any unexpected toxicity.

International audience; INTRODUCTION: Erdheim-Chester disease is a rare form of non-langerhans histiocytosis and its etiology is still not well established. The aims of the study were to assess the value of the bone scintigraphy and the 18F-FDG PET/CT for the diagnostic and for the latter in the therapeutic evaluation. METHODS: We retrospectively reviewed 49 patients suspected of Erdheim-Chester disease between 2004 and 2016. Bone scintigraphy was compared with histopathology and PET-CT to conventional morphological examinations and bone scintigraphy. For therapeutic evaluation, thresholds similar to PERCIST 1.0 were used. RESULTS: Forty-nine bone scintigraphy were evaluated with a sensitivity of 100%, a specificity 97%, a positive predictive value 90% and a negative predictive value of 100%. Eight patients had at least an initial PET-CT. The sensitivity compared to conventional morphological examinations differed from the location but was excellent for orbital, bone and vascular involvements. Specificity was comparable between the different examinations. Six patients treated with interferon® and three with vemurafenib® were followed by PET-CT. PET-CT, in agreement to clinicobiological data, identified 4 partial responses and one complete response with interferon® et two partial responses and one complete response with vemurafenib®. CONCLUSION: Our retrospective study suggests that bone scintigraphy and 18F-FDG PET/CT could be useful in the initial assessment of Erdheim-Chester disease but also for the latter in the therapeutic evaluation.

Resume Introduction Il existe un large panel de methodes de segmentation, mais actuellement aucune methode ne peut etre consideree comme la reference (Gold standard). Le but de cette etude a ete de comparer deux methodes de segmentation, l’une basee sur le maximum intensity projection (MIP-based) a une autre, PETVCAR®, pour mesurer les total lesion glycolysis (TLG) en TEP au 18-fluorodesoxyglucose (FDG) chez des patients suivis pour un melanome en evolution metastatique traite par vemurafenib. Patients et methodes Seize patients ont ete suivis en TEP au 18-FDG avant et pendant le traitement par vemurafenib. Les TLG ont ete mesures par la methode basee sur le MIP et PETVCAR® puis analyses pour la TEP initiale, l’ensemble des TEP, par localisation et par somme de TLG par TEP et par patient. Resultats Il existe une bonne correlation entre les TLG des deux methodes (r = 0,96 avec p = 0 pour 439 lesions au total). La difference moyenne de TLG (TLG PETVCAR – TLG MIP-based) est negative. La methode basee sur le MIP semble segmenter de maniere plus large que PETVCAR® avec des discordances concernant des lesions volumineuses et heterogenes. Le SUVmax ne semble pas etre responsable de ces discordances. La correlation des differences de TLG a la moyenne est egalement forte, notamment pour les TLG des lesions osseuses, ganglionnaires et sous-cutanees. Conclusion Les deux methodes de segmentation presentent une bonne correlation dans la plupart des cas, meme s’il existe quelques discordances pour les lesions volumineuses et heterogenes, segmentees de maniere plus large avec la methode MIP-based que PETVCAR®.

Introduction La multiplication des TEP-FDG au cours du suivi du melanome confronte souvent le dermatologue a la decouverte fortuite d’hypermetabolismes thyroidiens (HMT), posant la question, peu etudiee dans la litterature, de leur nature et de la conduite a tenir. Materiel et methodes Analyse retrospective de 1762 TEP-FDG chez 744 patients suivis pour un melanome dans 2 centres francais a forte activite dermato-oncologique. Les comptes-rendus mentionnant la decouverte d’un HMT menaient a une relecture des TEP-FDG afin d’en preciser les caracteristiques, et a l’analyse, dans les dossiers medicaux, des explorations realisees, du diagnostic final et de la prise en charge. Resultats Un HMT etait diagnostique chez 57 patients (7,7 %). Apres exclusion des patients avec antecedents thyroidiens connus et des dossiers sans renseignements cliniques, 41 cas ont ete analyses. Des explorations complementaires etaient realisees chez 35 patients (85 %) [32 biologies, 27 echographies, 14 cytoponctions]. Sept cas (17 %) correspondaient a des lesions malignes : 4 metastases thyroidiennes de melanome (9,7 %) et 3 carcinomes papillaires de la thyroide (CPT) (7,3 %). Treize cas (32 %) etaient lies a des thyroidites (dont 11 induites par un traitement anti-CTLA4 ou anti-PD1), et 13 (32 %) a des lesions benignes (goitres ou nodules benins.) Tous les HMT lies a des lesions malignes etaient focaux (SUVmax 9,1[1,6–23,6]), sans traduction clinico biologique, tandis-que les thyroidites conduisaient a des HMT diffus. Dans les 4 cas de metastases thyroidiennes, le diagnostic d’HMT etait concomitant a une evolution multiviscerale dont 3 avec metastases cerebrales. Le diagnostic a ete confirme par cytoponction apres echographie thyroidienne dans 2 cas. De meme, les 3 CPT ont ete diagnostiques par echographie thyroidienne puis cytoponction. Ces diagnostics n’ont pas modifie la prise en charge du melanome et les CPT ont beneficie d’une simple surveillance. Conclusion Bien que l’apparition d’un HMT au cours du melanome ne soit pas exceptionnelle, les metastases de melanome restent rares. Elles se presentent sous la forme d’un nodule hypermetabolique, asymptomatique, generalement associe a evolution multiviscerale. Dans ce contexte, les explorations invasives paraissent peu pertinentes. Cependant en cas d’HMT focal chez des patients avec une faible masse tumorale ou une evolution latente, celles-ci s’averent necessaires pour ne pas meconnaitre une neoplasie thyroidienne primitive ou une nouvelle localisation metastatique du melanome. Enfin, la TEP-FDG est un examen contributif pour le diagnostic des thyroidites immunoinduites.

La pratique du ganglion sentinelle (GS), largement diffusee en France, varie entre les etablissements. Lors d’un atelier de travail parraine (JFMN 2018), la pratique actuelle a ete evaluee via un questionnaire. Au total, 74 participants ont repondu par vote electronique. Un total de 51 % exercaient en CHU/CHG et 16 % dans un CLCC. Le nombre d’actes de GS par semaine etait entre 1 et 10 pour 49 %, plus de 11 pour 21 % et moins d’un pour 22 %. Le cancer du sein etait l’indication la plus frequente (85 %), suivi du melanome (62 %) et des cancers des organes genitaux externes (58 %), alors que le GS dans le cancer du col uterin n’etait realise que par 36 % des participants et le cancer des VADS par 27 %. Pour 67 % des medecins, la methode colorimetrique etait associee a la methode isotopique au moins dans certaines indications. Dans le cancer du sein, selon 65 % des medecins, la realisation d’une image scintigraphique pour attester du drainage sentinelle etait necessaire, cependant, 41 % ont declare qu’elle n’etait pas toujours utilisee par le chirurgien. L’observation d’un drainage tardif en l’absence d’un drainage precoce etait possible pour 65 % des participants. Les elements alterant la detection du GS etaient principalement l’antecedent de chirurgie mammaire (72 %), l’IMC de la patiente (59 %) et le site d’injection (54 %). La presence d’un repere radiologique etait consideree comme une limite au GS uniquement par 19 % du panel. De facon globale, les principales difficultes rencontrees dans la pratique du GS etaient l’echec de la technique chez certains patients (51 % des medecins), le drainage complexe et les localisations atypiques (43 %), ainsi que la non-specificite du radiotraceur avec multiplicite des GS tardifs (34 %). L’effet phare dans certaines localisations tumorales et la formation insuffisante a la technique etaient rapportes par 26 % des medecins. En termes de pratique ambulatoire, 58 % des participants ont declare realiser le GS sur 1 jour et 65 % sur 2 jours Les ressources humaines et materielles (57 %) et les aspects logistiques (54 %) etaient rapportes comme les limites majeures a la pratique de l’ambulatoire. En conclusion, le panel evalue reflete l’avis d’une petite proportion de medecins nucleaires. Cependant, leur participation a cet atelier temoigne de leur implication pour cette technique. Selon ces resultats, des difficultes sont parfois rencontrees, suggerant que des ameliorations dans le parcours du patient beneficiant d’un GS restent souhaitables.

Resume La tomographie par emission de positons (TEP) au 18 F-fluorodesoxyglucose (TEP 18 F-FDG) est une technique d’imagerie nucleaire dont l’interet en oncologie ne cesse de croitre. Dans le cadre d’une radiotherapie externe, l’optimisation du plan de traitement, l’evaluation de la reponse therapeutique, le suivi objectif sont autant d’etapes qui necessitent une quantification precise des volumes d’interet. Dans cet article, nous presentons une nouvelle methode de segmentation quasi-automatique, operateur independant et ne necessitant pas de calibration prealable du tomographe. Cette methode basee sur la theorie des possibilites permet, via l’utilisation de degres d’appartenance, de prendre en compte l’incertitude et l’inexactitude inherentes aux images. Les resultats obtenus sur des images issues d’un fantome (pourcentage d’erreur = 18,4 % (moyenne) ± 9,7 % (ecart-type)) ainsi que sur des donnees simulees (erreur de classification = 23,6 % (moyenne) ± 18,6 % (ecart-type) pour un SUV de 4,5) montrent l’efficacite et la robustesse de la methode.

Resume Objectif Mettre en place un cadre d’evaluation de methodes automatiques de segmentation des volumes tumoraux en TEP. Patient et methodes Les examens TEP de 18 patients presentant un lymphome non hodgkinien ont servi de base de donnees. Une lesion cible a ete designee par patient. Chaque lesion a ensuite ete contouree manuellement trois fois par un groupe de cinq experts. Quatre methodes automatiques (application d’un seuillage fixe egal a 42 % de la SUV maximale, methode MIP-based, methode proposee par Daisne et al., methode proposee par Nestle et al.) ont alors pu etre evaluees par comparaison avec l’ensemble des segmentations manuelles. Resultats Les contours realises par les experts ont permis de conclure a une variabilite intra-operateur moderee et a une reproductibilite interoperateurs assez faible. Par ailleurs, les tests statistiques realises sur divers criteres quantitatifs n’ont mis en evidence aucune difference significative entre la methode MIP-based, la methode de Daisne et al. et celle de Nestle et al. La methode de seuillage fixe a 42 % de la SUV maximale apparait moins performante. Conclusion Ce travail a permis de proposer un protocole d’evaluation et de comparaison de methodes de segmentation. La base de donnees generee pour cette etude pourra etre diffusee en ligne pour la communaute afin de simplifier l’evaluation de toute nouvelle methode de segmentation.

Resume Cette etude bibliographique traite des methodes de segmentation utilisees en tomographie par emission de positons pour la determination des volumes tumoraux. Nous proposons ici un etat de l’art sur les techniques se basant sur un seuillage, qu’il soit fixe ou adaptatif. Les methodes trouvees dans la litterature sont analysees du point de vue de leur methodologie, de leurs avantages et inconvenients. Enfin, nous proposons une synthese comparative sous forme de tableaux.

Resume Les vascularites inflammatoires des gros troncs sont representees par les maladies de Horton et de Takayasu. Si l’imagerie radioisotopique monophotonique peut parfois montrer des aspects inhabituels dans ces pathologies, la tomographie par emission de positons au fluorodesoxyglucose semble pouvoir presenter un attrait particulier et certaines indications au cours de la prise en charge de ces patients. Ces indications restent cependant pour la plupart a valider, en particulier pour differencier de discretes activites inflammatoires des parois vasculaires de fixations physiologiques et/ou atheromateuses.

Resume A partir d’une experience de pres de sept ans (2002–2008) de radio-immunotherapie des lymphomes non hodgkiniens, concernant 160 traitements, une analyse des indications a ete realisee : protocoles de recherche clinique, indications de l’AMM ou medicalement justifiees. Quelques elements portant sur les points pouvant etre bloquants sont detailles : coordination entre les differents services regionaux d’hematologie et le service de medecine nucleaire, marquage et radioprotection.

Resume Propos La tomographie d'emission de positons (TEP) a connu un essor recent et rapide en France ces dernieres annees. La TEP utilise actuellement un traceur derive du glucose : le fluorodeoxyglucose (FDG) et realise donc une imagerie fonctionnelle du metabolisme cellulaire. Restreintes essentiellement a l'oncologie, les indications de la TEP pourraient evoluer a la lumiere de donnees recentes de la litterature, notamment dans le domaine de la medecine interne. Actualites et points forts Les vascularites des gros vaisseaux, les fievres au long cours et les syndromes paraneoplasiques commencent a avoir ete etudies par plusieurs equipes avec des donnees suffisamment concordantes et precises pour commencer a entrevoir l'utilisation de la technique. Perspectives et projets De nombreuses pathologies, encore peu etudiees en TEP, pourraient voir leur prise en charge modifiee si la TEP au FDG confirme les premieres donnees recemment publiees notamment dans les polyarthrites inflammatoires, les maladies inflammatoires chroniques de l'intestin, le lupus, l'histiocytose ou les fibroses pulmonaire et retroperitoneale. Un effort de recherche clinique semble necessaire afin de preciser nos connaissances dans ces pathologies, ce qui passera certainement par une collaboration accrue entre les internistes et les medecins nucleaires.

Summary Objectives The diagnosis of osteomyelitis in patients with diabetic foot is difficult both clinically and radiologically. An early diagnosis is crucial to optimize therapeutic strategy. Among the diagnostic methods currently used, scintigraphy with ex-vivo labelled white blood cells is the gold standard, but cannot be performed in all centers; therefore 67 Gallium citrate ( 67 Ga) imaging in combination with a bone scintigraphy is still widely used. Method The results of imaging 24 diabetic patients with 31 suspected osteomyelitic lesions using the antigranulocyte Fab' fragment (Sulesomab or LeukoScan® or immunoscintigraphy) were prospectively compared with results from the bone scan coupled with 67 Ga. The diagnosis of osteomyelitis was confirmed by either biopsy or follow-up, radiological imaging and clinical outcome. Results and conclusion Sulesomab correctly identified 12 of 18 osteomyelitic lesions while 67 Ga was able to detect only 8 of 18. Therefore the sensitivity is 67% for Sulesomab and 44% for 67 Ga. Among the 13 non-osteomyelitic lesions imaging with Sulesomab was able to rule out infection in 11 cases and 67 Ga in 10 cases. The specificity is therefore 85% for Sulesomab and 77% for 67 Ga. Image interpretation for Sulesomab in this group of patients is occasionally suboptimal when imaging is performed at 3 hours post injection. High vascular background in the early images may obscure infection especially in small bones. Practically, scintigraphy with Sulesomab is fast and simple due to ease of labeling, no ex-vivo handling of blood, low radiation and provides rapid diagnosis. The diagnosis of osteomyelitis obtained by the antibody fragment scintigraphy influences the management (guided biopsy) and therapy. In several patients, imaging with Sulesomab was able to rule out osteomyelitis, helping to avoid useless antibiotic therapy and its associated side effects.

The use of fluorine-18 fluorodeoxyglucose (FDG) in positron emission tomography (PET) is a major advance in imaging in the recent past. Its use in breast and gynaecologic cancers is not well established and needs to be discussed for each patient. This discussion must rely on a better knowledge of potential interests as well as of the limits of metabolic or logistic limits of PET.

Parmi l'arsenal therapeutique de la douleur des metastases osseuses osteoblastiques des cancers osteophiles, la radiotherapie metabolique reste une modalite peu connue et souvent utilisee en ultime recours. Le but de cette mise au point est de mieux faire connaitre cette technique, non invasive pour le patient et de discuter de la place de celle-ci dans la panoplie therapeutique. Souvent releguee au bas de celui-ci, la radiotherapie metabolique est actuellement proposee plus tot a un stade ou les metastases osseuses apparaissent en nombre limite a la scintigraphie osseuse.

Resume Nous avons realise une etude clinique d'un nouveau dosage serique de la chromogranine A. Notre etude prospective, sur deux ans, a porte sur un ensemble de 282 serums se repartissant comme suit : groupe Temoins (n = 98), Temoins hypertendus du groupe A (n = 39) et 145 tumeurs neuroendocrines composees de 32 pheochromocytomes, 21 cancers medullaires de la thyroide, 17 tumeurs des ilots pancreatiques, 30 hyperparathyroidies primaires, 15 gastrinomes et 30 carcinomes neuroendocrines. La chromogranine A (Cg A) serique est un marqueur sensible et specifique des tumeurs neuroendocrines. Les resultats les plus probants de notre etude ont ete obtenus pour les pheochromocytomes, les gastrinomes et les tumeurs carcinoides avec des sensibilites respectives de 87,5, 100 et 77 %. Lors du diagnostic de pheochromocytome, les taux de Cg A sont tres significativement correles a la masse tumorale et aux taux de metanephrines urinaires. Ce sont des index precoces pour la radicalisation de l'exerese. Ce dosage serique est peu sensible aux interferences medicamenteuses ou alimentaires. Une etude portant sur le suivi des patients dans le temps fournira des renseignements complementaires de ceux que nous avons obtenus.

In apparently localized amyloidosis, there is no appropriate test to determine whether systemic deposits exist. We studied the value of serum amyloid P component (SAP) scintigraphy and labial salivary gland (LSG) biopsy on patients with apparently localized amyloidosis in 12 patients who had neither clinical nor biological evidence of systemic amyloidosis. All patients had an LSG biopsy and echocardiography. Iodine-123-labelled serum amyloid P component ( 123 I-SAP) scintigraphy was performed in all patients. Whole-body scintigraphy was done, and tissue retention was evaluated at 24 h and 48 h. Of these 12 patients, three had amyloidosis in their LSG and had abnormal 123 I-SAP scintigraphy; these three had a secondary clinical history of systemic amyloidosis. Three other patients had abnormal 123 I.SAP scintigraphy without detectable systemic amyloid deposits, but one had a previous history of bilateral carpal tunnel syndrome treated with infiltration. 123 I-SAP scintigraphy in association with LSG biopsy may be helpful in determining the localized or systemic character of amyloid disease.

The purpose of this study was to assess the value of the serum amyloid P (SAP) component scintigraphy in patients with primary amyloidosis (AL).Pure human SAP labeled with iodine-123 (123I-SAP) was given intravenously to 24 patients with biopsy-proven systemic amyloidosis (15 without multiple myeloma = group 1, and 9 with multiple myeloma = group 2) and to 6 patients with multiple myeloma without any clinical or biological signs of amyloidosis (group 3). Whole-body images as well as regional views and tissue retention levels were obtained after 24 hours. Our study was approved by the institutional review committee and all individuals gave informed consent and were prospectively studied (median 13 months, range 1 to 47 from the date of the scintigraphy to May 1995).Organ localization of 123I-SAP, indicating the presence of substantial visceral amyloid deposits, was observed in all patients in group 1 and 2. The organ uptake of 123I-SAP included the spleen (1 patient was splenectomized) in 20 of 23 cases (87%), the liver in 15 of 24 (60%), and the kidneys in 6 of 24 (25%). Myocardial 123I-SAP was never seen although 13 out of the 24 patients had clinical or echographic data for amyloidosis. Twenty-four hour tissue retention was significantly elevated in all patients (group 1 and group 2): 55.66% +/- 19.16% in group 1 and 34.37% +/- 24.92% in group 2, as compared with normal levels24%. The sensitivity of the technique was 79% when only organ uptake was considered but reached 100% when tissue retention was also considered. The 24-hour tissue retention might be correlated with the severity of the amyloidosis: mean survival in patients with tissue retention greater than 50% was 11.3 months versus 24.5 months in patients with levels less or equal to 50%. Five of the 6 patients with multiple myeloma without evidence of amyloidosis had abnormal 123I-SAP imaging and 24-hour tissue retention levels. In 2 of them, amyloidosis was secondly detected. In the 9 patients who had two scintigraphies, variations in 24-hour tissue retention values were in accordance with the clinical evaluation.Spleen and liver distribution of amyloidosis is mostly revealed by 123I-SAP scintigraphy in patients with AL amyloidosis. The uptake of 123I-SAP appeared in proportion to the quantity of amyloidosis present in different tissues, and the relative quantity of amyloid deposits in the myocardium, carpal tunnel, digestive tract, and kidneys was often small and seldom visualized by 123I-SAP scintigraphy. In contrast 24-hour tissue retention levels were abnormal in all cases of known AL amyloidosis. This may be a positive argument for the diagnosis of amyloidosis when histopathological tests are normal. Tissue retention levels appear important as they may be correlated with survival.

The cerebral distribution of HMPAO was mapped tomographically by SPECT in 20 patients with an intra cerebral haematoma. The images were assessed visually and by an analysis of an asymmetry index (AI) for various cerebral areas. Visual inspection identified the lesion in each of the 20 cases. Reduced tracer activity and abnormal AI were consistent findings. Remote effects (diaschisis) were also observed in the adjacent (19 cases) and frontal (14 cases) cortex, and in the controlateral cerebellum (16 cases). Sequential studies at 60, 150 and 300 minutes in 10 patients showed remarkably stable patterns. HMPAO maps were compared with cerebral blood flow (CBF) measured with 133 Xenon (133Xe) in eight cases. The two methods showed similar results in the region of a lesion, but remote effects were more obvious with the 133Xe in two patients.

International audience; The authors have developed a simple phantom and dedicated software for the quality assessment of positron emission tomography (PET) scanners. The phantom is a parallelepiped box filled with a relatively low activity 18FDG solution and in which simple test objects are placed. Various image quality parameters are checked, including signal-to-noise ratio, image uniformity, slice thickness, slice sensitivity profile, spatial resolution, and dose calibration accuracy. Automatic image analysis consists in detecting surfaces and objects, defining regions of interest, acquiring reference point coordinates, and establishing gray-scale profiles. The total time needed for quality assessment (preparation and image acquisition) is less than 15 min with 37 MBq (1 mCi) 18FDG. The system's ease of use encourages frequent image quality assessment-for example, the comparison of PET scanners in interdepartment studies and the monitoring and evaluation of possible drifts over time. By way of an example, the authors present weekly quality assessment results obtained over up to 7 months at four PET facilities.

Fluorodeoxyglucose positron emission tomography (FDG-PET) is a promising imaging technique that has already proven effective in modifying patient care in oncology. Fluorodeoxyglucose still remains the main radiopharmaceutical agent routinely used for PET imaging. A growing interest has recently lead to broaden PET research on benign disorders. The field of inflammatory or immune diseases and globally the field of internal medicine could also be impacted by FDG-PET.Great vessels vasculitides and fever of unknown origin have both been studied by several teams and could become indications for PET. In addition, current indications now extend to paraneoplastic syndromes. It is thus possible to foresee that the clinical applications for PET will continue to expand in these patients.In the future, inflammatory arthritis, chronic inflammatory bowel diseases, systemic erythematous lupus, histiocytosis, or pulmonary and retroperitoneal fibrosis might benefit from PET even if, available data remains scarce to this day. Although PET will probably alter the landscape of patient management in internal medicine in the near future, additional clinical research is still needed to ascertain the exact role of PET.

The use of fluorine-18 fluorodeoxyglucose (FDG) in positron emission tomography (PET) is a major advance in imaging in the recent past. Its use in breast and gynaecologic cancers is not well established and needs to be discussed for each patient. This discussion must rely on a better knowledge of potential interests as well as of the limits of metabolic or logistic limits of PET.

To define a clinical and secretory profile of paragangliomas extra-adrenal chromaffin tumors.From 1971 throughout 2002, 39 paragangliomas have been observed in 38 patients (22 male, 16 female, average age 41,2 years).Four were located above the diaphragm, 35 were sub-phrenic (6 of the organ of Zuckerkandl), 32 secreted catecholamines, 23 were hypertensive (with only one without hypersecretion of catecholamines). Among 29 (131)I-metaiodobenzylguanidine scans (MIBG) reviewed, 20 tumors took up the radiopharmaceutical. The treatment was surgical in 35 cases with addition of external radiotherapy and MIBG in one case each; two patients died before any treatment. Two patients with persistent disease after surgery were successfully treated by surgery or MIBG. Histologically, 20 were malignant and 17 were seemingly benign. All exclusive dopamine secreting paragangliomas were malignant. Six patients relapsed two of which for a tumor initially classified as benign. The treatment of recurrences was surgical, by MIBG or by external radiotherapy. Nine patients had a family history of chromaffin tumor(s). The genetic survey made in five of these nine patients was positive in all cases.

To report feasibility and efficacy of radioguided mini invasive hyperparathyroidism surgery.From November 1998 to August 2000, 75 patients with primary hyperparathyroidism have been operated on by radioguided surgery within 90 to 180 minutes following i.v. injection of a diagnostic dose of MIBI and after parathyroid scanning with planar and oblique views. Exclusion criteria were thyroid pathology requiring surgery and suspicion of multiple endocrine neoplasia. A 20% step-up between the background noise and tissue uptake was the diagnostic threshold for parathyroid hyperfunctioning tissue.A 20% step-up was observed in only 17% of cases overall; all cured, but two. Various angles of application of the probe can result in significant discrepancies of recorded uptake for the same spot. These results demonstrate a physiological step-up between the ipsilateral unaffected upper and lower quadrants of the neck (range: -17 to -8%), because of the proximity of supraortic vessels (upper neck-upper mediastinal gradient: -44 to -30%). Therefore, significant ratios are meaningful only between either the symmetrical left and right controlateral quadrants respectively, and not between the upper and the lower ipsilateral quadrants. Eleven per cent (8/75) of preoperative scannings were non-contributory, and probe detection was contributory in 3/8 cases only.Benefit of the technique is limited in routine, but it can be helpful in redo cases if the offending gland is not located in close surroundings of tissues physiologically taking up the radiopharmaceutical (salivary glands, great vessels and heart).

CT scan performed for non-adrenal related symptoms detects an adrenal mass or 'incidentaloma' in 0.4 to 4.3% of cases, and most authors advocate a non-operative policy, after minimal but careful work-up aimed at excluding pheochromocytoma and aldosteronoma. The breakthrough of laparoscopic adrenalectomy has led some to challenge this attitude. This retrospective study focused on the outcome of non-operated adrenal masses.From 1986 through 1999, 126 patients (64 men and 62 women) presented with an incidental mass of the adrenal fossa, and a non-surgical attitude was elicited. Mean size was 36.5 mm in diameter. All patients underwent an in-depth clinical, biochemical and imaging work-up. They have been stratified into two groups: group I: no contraindication to surgery (n = 95); and group II: contraindication to surgery (frail patients, invasive adrenal or metastatic extra-adrenal cancer) (n = 31).With a mean follow-up of 4.3 years, 17 patients were lost to follow-up (13.5%), including 11/95 in group I; 36 were dead (28.5%), including 12/95 in group I (no adrenal-related death) and 24/31 in group II; 72 were alive and well without operation, including only one in group II; one patient was operated for a benign adrenal adenoma removed at the time of surgery for aortic aneurysm.Careful clinical, biochemical, imaging and nor-iodo-cholesterol scintigraphy with definite uptake by the adrenal mass, a strong indicator of benignancy, allows surgical indication to be postponed, and is likely to cancel it if, at one-year follow-up, imaging studies show no change in the mass.

Introduction After primary CRT, a non-invasive evaluation of the tumour response could help in the treatment decision to identify patients who may benefit from surgery. Whether FDG-PET provides clinically relevant information remains questionable. The objective of this prospective trial was to evaluate the role of 18F-Fluorodeoxyglucose-positron emission tomography (FDG-PET) in the assessment of tumour response after the completion of neoadjuvant chemoradiation (CRT) in patients with locally advanced resectable oesophageal cancer. Methods Operable patients with locally advanced oesophageal cancer (clinically staged T3 N0-1 M0) were enrolled. The complete treatment plan included neoadjuvant CRT (cisplatin + 5-Fluorouracil/45 Gy) followed 6–8 weeks later by a transthoracic en bloc oesophagectomy. Morphological evaluations combined with FDG-PET results were performed 2 weeks before and 4–6 weeks after the completion of CRT. Intratumoural pre- and post-treatment FDG-standardised uptake values were assessed (SUV1, SUV2, percentage change). These variables were correlated with pathologic and morphologic responses and survival. Investigators were blinded to the FDG-PET results unless metastatic disease was suspected. Results Out of 60 total patients, 46 underwent the complete treatment plan (median age: 60.1 years; adenocarcinoma: 25 patients; squamous cell cancer: 21 patients). A major pathological response occurred in 19.6% of patients and was associated with a favourable outcome (p = 0.057). Neoadjuvant CRT led to a significant reduction in intratumoral FDG-uptake (p 0.001). No significant association was seen between a pathologic response (either complete or major) and the FDG-PET results (p > 0.280). The SUV2 value was correlated with a morphological response and the possibility to perform an R0 resection (p 0.018; ROC analysis: SUV2 threshold = 5.5). No significant association was found between metabolic imaging and recurrence or survival. Conclusion FDG-PET does not effectively correlate with pathologic response and long-term survival in patients with locally advanced oesophageal cancer undergoing neoadjuvant CRT followed by surgery (registered on http://www.e-cancer.fr website, RECF0350, 2002-1936R). Funding Funded by the French ministry of Health – Programme Hospitalier de Recherche Clinique 2002. Competing interests None declared.

The aim of this study was to investigate local and remote regional cerebral blood flow in patients with prefrontal lesions resulting from rupture (and operation) of aneurysms of the anterior communicating artery. The localization and severity of the lesions were evaluated by magnetic resonance imaging on T2 sequences. Blood flow measurements were performed in 21 patients at least 3 weeks after surgery using single-photon emission computed tomography. Flow values were calculated in 10 regions of interest in each cerebral hemisphere and compared with those of 21 control subjects matched for age. A drop in regional cerebral blood flow, predominating on the right side, was observed in the frontal areas. Flow values were not reduced in the thalamus and striatum but were significantly elevated in the posterior cortical areas and cerebellum. This latter phenomenon was significantly correlated with the severity of frontal lesions on magnetic resonance imaging. Blood flow drop in frontal areas was correlated with the cerebral lesions, which predominated in the anterior prefrontal lobe, on the side of the surgical flap; most of these prefrontal lesions were likely due to the surgical procedure and not to classic arterial spasm. Elevated perfusion in the temporo-parieto-occipital cortex and cerebellum might be due to the release of a physiological inhibition exerted by the prefrontal cortex.

Magnetic resonance imaging (MRI) has shown a great reduction in medial temporal lobe and hippocampal volume of patients with Alzheimer's disease as compared to controls. Quantitative volumetric measurements are not yet available for routine clinical use. We investigated whether visual assessment of medial temporal lobe atrophy (MTA) on plain MRI films could distinguish patients with Alzheimer's disease (n = 21) from age matched controls (n = 21). The degree of MTA was ascertained with a ranking procedure and validated by linear measurements of the medial temporal lobe including the hippocampal formation and surrounding spaces occupied by cerebrospinal fluid. Patients with Alzheimer's disease showed a significantly higher degree of subjectively assessed MTA than controls (p = 0.0005). Linear measurements correlated highly with subjective assessment of MTA and also showed significant differences between groups. Ventricular indices did not differ significantly between groups. In Alzheimer's disease patients the degree of MTA correlated significantly with scores on the mini-mental state examination and memory tests, but poorly with mental speed tests. This study shows that MTA may be assessed quickly and easily with plain MRI films. MTA shown on MRI strongly supports the clinical diagnosis of Alzheimer's disease, is related to memory function, and seems to occur earlier in the disease process than does generalised brain atrophy.

Objectifs pedagogiques Connaitre la technique de realisation d’un scanner surrenalien. Connaitre les sequences a utiliser pour une IRM surrenalienne. Decrire l’apport et les limites du scanner et de l’IRM dans l’exploration d’un incidentalome surrenalien. Decrire l’apport et les limites du scanner et de l’IRM dans l’exploration d’un nodule surrenalien chez un patient porteur d’une tumeur maligne. Decrire l’apport et les limites du scanner et de l’IRM dans l’exploration d’un nodule surrenalien chez un patient ayant un syndrome endocrinien d’hypersecretion avec ou sans hypertension.