TEP au 18-FDG et cancers ORL : récidive et surveillance post-thérapeutique

Recurrence of head and neck squamous cell carcinomas occurs early and currently, with poor prognosis. Post-therapeutic surveillance aims to diagnose a recurrence as early as possible in order to perform curative salvage therapy. The risk of recurrence is highest in locally advanced cancers. Morphological imaging, including Computed Tomography (CT Scan) and magnetic resonance imaging, can be limited by the anatomic changes following surgery and radiotherapy, and sometimes cannot provide early diagnosis of recurrence. Histology presents some risk of morbidity, especially in irradiated tissues, and sampling error. Positron Emission Tomography (PET) with 18F-fluorodeoxyglucose (FDG) is superior to conventional imaging for the diagnosis and staging of recurrence, especially when it is performed three months after the end of treatments. FDG-PET has high sensitivity and negative predictive value for recurrence, so that further morphological and invasive investigations should not be performed in case of negative examination. On the other hand, because of its limited specificity and positive predictive value, any positive PET finding should be documented, in order to avoid false positives findings. The diagnosis of recurrence is the field of application in which FDP-PET has the greatest impact on head and neck cancer management: it is considered as a standard. However, the interest of FDG-PET during systematic follow-up has not yet been confirmed. PET should only be performed in difficult cases and within evaluation protocols.     

« Du gris clair au gris foncé… » Exploration de la carcinose péritonéale par TEP-TDM

FDG or Fdopa PET/CT is a powerful imaging technique for detection and characterization of peritoneal carcinomatosis. Diagnosis features and main differential diagnoses are presented from clinical reports.     

Intérêt de la TEP/TDM dans le diagnostic de la carcinose péritonéale : à propos d’une observation

PET/CT is a significant examination recognized in the detection of tumors and their metastases. Through a rare case of peritoneal carcinomatosis complicating an endometrial carcinoma, the authors discuss utility of FDG-PET/CT in the diagnosis and follow-up of this disease.     

Mesure par μTDM et dilution de nanocolloïdes-99mTc de la surface péritonéale chez le rat insuffisant rénal au cours d’une expérience de dialyse péritonéale

Peritoneal dialysis takes an important place for the management of patients with end-stage renal failure, especially for young children. The optimization of its efficiency needs to use biocompatible dialysis solutions but also to improve peritoneal surface area (PSA) recruitment. Small animals experimental models are an essential step for PSA measurements. We propose a fast method using in vivo microcomputerized tomography (μCT) and isotopic dilution method to evaluate the PSA.     

TEP/TDM au FDG et hibernome : à propos d’un cas

Hibernoma is a rare benign tumour of soft tissue, generally asymptomatic, usually discovered in young adults. It is a form of lipoma that originates from brown adipose tissue. Its diagnosis is based on histology, the main differential diagnoses being lipoma and liposarcoma. Its appearance on FDG PET/CT has being described only in few case reports. We report here the case of a 68-year-old patient with ENT cancer in whom an adipose tumour in the left axilla has been discovered on CT performed for staging. The diagnosis of hibernoma was suggested in the report of FDG PET/CT examination and was consistent with results of other imaging modalities. On MRI, contrast enhancement was observed after gadolinium contrast injection, which was not typical for a lipoma. On PET/CT, the FDG uptake by the adipose tumour was very intense (SUVmax = 16), which is characteristic for hibernoma that derives from brown adipose tissue. Imaging was unable to distinguish between hibernoma and liposarcoma. The diagnosis of benign mixed hibernoma-lipoma was ascertained on histopathology after complete resection of the tumour. Elements favouring hibernoma over liposarcoma are present in this observation: high avidity for FDG (SUVmax > 10) and a fluctuating intensity of uptake, SUVmax of the tumour increasing from 16 to 48 within 16 months in the presented case. A high SUVmax on FDG PET in an adipose tumour on CT seems to be more suggestive of a benign tumour, hibernoma, than of its malignant counterpart, liposarcoma.     

Neurolymphomatose du nerf sciatique en TEP au FDG : à propos d’un cas et revue de la littérature

We are reporting the case of a woman who has been suffering from sciatica for several months. A neurolymphomatosis of the sciatic nerve was found. In this report, we present the characteristics of this lesion in conventional imaging and in FDG PET.     

TEP/TDM au FDG et toxicité pulmonaire à la bléomycine : à propos d’un cas clinique

Patients treated with bleomycin should be frequently monitored during and after treatment. Actually this treatment can cause pulmonary toxicity and may progress to pulmonary fibrosis. Extreme care is required in patients with a severe deterioration of renal function or impaired lung function. PET/CT can be a useful tool for the early diagnosis of this complication. We report a case of bleomycin-induced pneumonitis and discovered during a PET/CT performed for evaluation of Hodgkin's disease.