[Impact of whole body magnetic resonance imaging (MRI) in the management of melanoma patients, in comparison with positron emission tomography/computed tomography (TEP/CT) and CT]. / Apport de l'imagerie en résonance magnétique (IRM) du corps entier dans la prise en charge du mélanome : comparaison avec la tomoscintigraphie par émission de positons couplée à la tomodensitométrie (TEP-TDM) et à la TDM seule.

BACKGROUND: PET/CT has proven extremely useful in the management of melanoma patients, with great sensitivity (Se), but it tends to give false-positive results. Whole-body MRI (wb-MRI) is a new method that has made considerable progress. STUDY AIMS: The aim of this study was to assess the Se and specificity (Sp) of wb-MRI with a diffusion sequence for detecting melanoma metastasis compared to PET/CT. METHODS: This was a prospective study, including patients at any AJCC (American Joint Committee on Cancer) stage of melanoma. PET/CT, wb-MRI and CT, including the brain, were performed on the same day. For each of the three exams, the number of lesions per patient was counted. The treatments proposed by the doctor immediately after PET/CT and then MRI were compared. RESULTS: Forty patients were included and a total of 72 metastases were noted. CT detected 53 of these metastases (Se 80%, Sp 95%), while PET/CT detected 53 metastases, with four false-positive (Se 74%, Sp 89%) and Wb-MRI detected 59, with two false-positive (Se 83%, Sp 96%). The sensitivity of MRI was distinctly superior to PET/CT for both hepatic and pulmonary lesions. The treatment proposed after PET/CT and MRI differed in three cases: one patient was falsely reclassified by MRI (AJCC IV instead of IIB) while two others were falsely reclassified by PET/CT (AJCC IV instead of IB and IIIC). Exclusively whole-body scan influenced the treatment of four patients (10%). CONCLUSION: Wb-MRI with diffusion sequence, which is less costly than PET/CT and is also non-radioactive, could play an important role in the detection of metastases in melanoma patients.

[Co-sensitization to drugs belonging to different chemical classes during the same episode of cutaneous adverse drug reaction: two cases]. / Deux médicaments de même imputabilité dans une toxidermie (deux cas): limite des tests épicutanés?

BACKGROUND: For the first time, 2 cases highlight the fact that, in the event of cutaneous adverse drug reactions under treatment associating 2 drugs, a positive test with one of the 2 does not authorize further readministration of the remaining drug without hospital surveillance. PATIENTS AND METHODS: A man had urticaria during treatment with pristinamycin subsequently replaced by ceftriaxon. All the patch-tests with synergistins were positive, whereas patch-tests, prick-tests and intradermal tests with betalactams were negative. The oral challenge with ceftriaxon was positive. A woman taking spiramycin developed a maculopapular rash which was slowly regressive despite substitution with cefixim and corticotherapy. Patch-tests, prick-tests and intradermal tests with macrolides and betalactams were negative. An oral challenge with spiramycin was positive. DISCUSSION: Sensitization to two antibiotics without shared chemical structures can occur during the same episode of a cutaneous adverse drug reaction, even without prior indication of sensitization to these drug classes. The mechanisms at play in this phenomenon are still debated, but this highlights the fact that reintroduction of any drug suspected at the time of a cutaneous adverse drug reaction must be performed under hospital surveillance, whatever the degree of imputability and even if skin tests with other drugs taken simultaneously were positive.