Application clinique des nouveaux traceurs TEP en oncologie. La vision d’un médecin nucléaire en Espagne

PET is an excellent and sensitive molecular imaging technique using positron-emitting radioisotopes coupled to specific ligands. Many biological targets of great interest can be imaged with these radiolabelled ligands. ¹⁸F-FDG is the most widely tracer PET used, but is not a oncospecific tracer and many malignancies are poorly imaged by FDG-PET. In the last years, the investigation and development of novel ligands will be an alternative to the limitations of FDG in clinical oncology. This review describes the current status of non-FDG PET tracers that have a potential clinical effect in the management of patients affected by cancer.     

Réflexions sur la place des médecins spécialistes en médecine nucléaire dans le dispositif d’annonce en cancérologie

Nuclear medicine physicians are very involved in French's oncology announcement procedure. However, their role needs to be analysed and evaluated. Before diagnosis’ announcement, information provided by nuclear medicine physicians are never neutral for patients. Information must not increase patient's anxiety or false patient's sense of reassurance. In this context, it seems necessary to engage in ethical reflexions about nuclear medicine physicians communication challenges.     

Fusion d’images en médecine nucléaire : des concepts à l’application clinique

In this paper, the authors propose a short overview of image fusion techniques in nuclear medicine. First, the methodological concepts of image fusion are discussed. Then, a sample of applications in nuclear medicine is presented. These applications ranging from diagnosis to guided therapy and monitoring clearly exemplify the challenges of image fusion in nuclear medicine.     

Intérêt de l’injection péritumorale de nanocolloïdes technétiés pour la détection du ganglion sentinelle mammaire interne

ObjectivesUntil now, the effectiveness of sentinel lymph-node biopsy (SLNB) has only been demonstrated for the detection of axillary lymphatic involvement in early breast cancer (cT1N0). The purpose of this study was to evaluate whether the detection of an extra-axillary internal mammary sentinel lymph node (SLN), using peritumoral injection of radiolabelled nanocolloids (NC), can lead to a modification in management for these patients.Materials and methodsA total of 538 consecutives SLNB was analysed from a cohort of 529 patients. Peri- and infratumoral injections of radiolabelled NC were made under ultrasound control.ResultsA SLN was identified on 524 occasions, 147 (28.1%) of which were located in the internal mammary chain (IMC). In 10 cases, the SLN in the IMC was not associated with an axillary SLN. One hundred and thirty-five surgical biopsies of the IMC SLN were performed without significant morbidity. Sixteen patients demonstrated local involvement of an IMC SLN, which on seven occasions was isolated to this region. For six of these patients, the finding of SLN involvement led to a recommendation for adjuvant chemotherapy. For 308 patients, for lack of IMC involvement, the adjuvant IMC radiotherapy could have been avoided (i.e.: 95% of the theoretical indications for adjuvant radiotherapy).ConclusionsPeritumoral injection of radiolabelled NC, associated with a systematic IMC SLN biopsy, enabled the rationalisation of management in patients with stage cT1 breast cancer and did not affect the usual performance of the technique nor led to a significant increase in morbidity. The long-term survival and morbidity outcomes of these therapeutic modifications, particularly with regards to radiotherapy, will need to be demonstrated.     

Intérêt de l’imagerie hybride TEMP-TDM pour la détection du ganglion sentinelle dans les cancers du sein

IntroductionSingle-Photon Emission Computed Tomography-Computed Tomography (SPECT-CT) is an hybrid technique which associates functional and morphological images. The aim of this study was to assess the role of SPECT-CT lymphoscintigraphy in sentinel node identification in patients with breast cancer.MethodsTwelve months prospective study was undertaken. Lymphoscintigraphy comprising planar and SPECT-CT acquisition was performed in 51 consecutive patients with breast cancer (mean age: 62 ± 11.3, range: 33–83 years). Planar and SPECT-CT images were interpreted separately and the two imaging techniques were compared with respect to their ability to identify sentinel node.ResultsAn add-value of SPECT-CT images was evidenced in 31% of cases: a more accurate anatomic localization in 21% of cases and identification of undeterminate sites of uptake in 10% of cases. Furthermore, SPECT-CT detected intramammary (4% of cases) and retromammary (2% of cases) sentinel nodes missed by planar imaging. SPECT-CT was more sensitive for internal mammary drainage detection (6% of cases). The added value proved higher in obese patients. Finally, functional and anatomical images fusion and three-dimensional overview provided clear and readily usable informations to the surgeon.ConclusionHybrid SPECT-CT imaging improves the preoperative localisation of sentinel nodes in patients with breast cancer, in particular in obese patients. SPECT-CT provides readily usable informations to the surgeon.     

Face à une suspicion de cancer ou de récidive de cancer : pratiques,communication et difficultés des médecins nucléaires français

Nuclear imaging techniques have been occupying an increasingly large place in the study of potentially cancerous morphological abnormalities. A National French survey was conducted among members of the French Society of Nuclear Medicine (Société française de médecine nucléaire) to study the usual practices of nuclear medicine physicians regarding information and communication during the “pre-announcement” stage of a cancer diagnosis. Sixty-six doctors (with an average of 44.7 years of age and 16.3 years of experience) working in mainland France responded to the online survey between November 2013 and February 2014. Most physicians said that they were uncomfortable in this kind of situation. Half of the doctors interviewed faced that situation at least 5 times a month. Communication habits were varied: 20% of them adopted a systematic approach (chose ‘always’ or ‘never’ to communicate information regardless of the patients’ demands) and 80% adapted their approach to the situations and to the patients (communication ‘on case by case basis’ and ‘upon request’). The survey also showed that professionals have contrasting views on the relevance, interest and risks of informing patients about the results of the tests in this kind of situation. Our study shows that it is necessary to discuss the position of nuclear medicine physicians in the pre-announcement procedure set out in the French Cancer Plan so as to reduce the challenges facing them while at the same time organizing and defining their roles.     

Gallium-68 : considérations pratiques pour le succès des applications cliniques au sein d’un service de médecine nucléaire

Gallium-68 is a radionuclide, which has, because of its favorable physical characteristics similar to those of fluorine-18, gained a great interest for labeling PET tracers. Furthermore, it is available onsite at the radiopharmacy, by elution of a ⁶⁸Ge/⁶⁸Ga generator that has a shelf life of around one year, which approximates the versatility of 99mTc in the labeling of tracers for scintigraphy. After a brief historical overview, this article lists the necessary equipment and components, and the choices to be made (currently and in the near future) to implement, in a radiopharmacy, ⁶⁸Ga-labelling of PET tracers for a nuclear medicine department.     

Étude du métabolisme d’acides aminès chezAspergillus oryzae

Résumé Aspergillus oryzae transforme rapidement l’ammoniaque en groupement aminé. Lorsqu’une colonie préformée de cette moisissure se cultive sur une solution du sel ammoniacal d’un des acides suivants: acides acétique, pyruvique, succinique, fumarique, α-cétoglutarique ou encore sur glucose en présence de sulfate ammonique, on trouve dans le mycélium plusieurs acides aminés, à l’état libre. Dans ces conditions, on y décèle toujours l’alanine, l’acide aspartique, l’acide glutamique et la glutamine; en outre on y met éventuellement en évidence d’autres acides aminés tels glycine, sérine, arginine, acide γ-aminobutyrique. L’acétate, le pyruvate, le succinate et le fumarate ammoniques, donnent lieu respectivement à l’apparition de plus nombreux acides aminés libres dans le mycélium que la glycine, l’alanine et l’acide aspartique. Les diverses substances essayées paraissent équivalentes en tant que sources de carbone, ce qui fait aussi ressortir le r?le des réactions de transamination dans le métabolisme étudié. Part I, II: Antonine van Leeuwenhoek19, 121, 245, 1953.