[Actinomycosis revealed by ulceration of the palate and gingiva]. / Actinomycose révélée par une ulcération du palais et de la gencive.

BACKGROUND: Actinomycosis is a chronic and extensive granulomatous, bacterial infection. Revelation by oral ulceration is rare. PATIENTS AND METHODS: A 76-year-old patient with diabetes was treated with dabrafenib for stage IV melanoma. A follow-up visit revealed two ulcerated, infiltrated and hyperalgesic lesions of the palate and gingiva. There were no associated signs. The laboratory findings were normal. The possibility of squamous cell carcinoma occurring with BRAF inhibitors was discussed, despite the rarity of such cases in the literature. Histological examination showed an actinomycotic grain. A scan of the facial mass showed no osteitis. Antimicrobial therapy was initiated with amoxicillin for four months, with a favorable outcome. DISCUSSION: Actinomycetes are Gram-positive filamentous saprophytic bacteria of the oral cavity and the gastrointestinal tract. They can become pathogenic under the influence of several factors. Cervicofacial involvement in the form of a peri-mandibular inflammatory nodule with secondary fistulation on the skin or in the mouth is the classic presentation. To our knowledge, no cases of opportunistic infection under BRAF inhibitors have been described. Only two cases of tuberculosis have been reported with sorafenib. The initial presentation led to suspicion of squamous cell carcinoma. In our patient, poor oral hygiene and diabetes were the two key factors considered. Moreover, this is the first case reported under dabrafenib, which does not appear to be a favoring factor. We would stress the importance of mucosal examination in patients treated with BRAF inhibitors.

Perfusion magnetic resonance imaging in pediatric brain tumors.

PURPOSE: The use of DSC-MR imaging in pediatric neuroradiology is gradually growing. However, the number of studies listed in the literature remains limited. We propose to assess the perfusion and permeability parameters in pediatric brain tumor grading. METHODS: Thirty children with a brain tumor having benefited from a DSC-MR perfusion sequence have been retrospectively explored. Relative CBF and CBV were computed on the ROI with the largest lesion coverage. Assessment of the lesion's permeability was also performed through the semi-quantitative PSR parameter and the K2 model-based parameter on the whole-lesion ROI and a reduced ROI drawn on the permeability maps. A statistical comparison of high- and low-grade groups (HG, LG) as well as a ROC analysis was performed on the histogram-based parameters. RESULTS: Our results showed a statistically significant difference between LG and HG groups for mean rCBV (p < 10-3), rCBF (p < 10-3), and for PSR (p = 0.03) but not for the K2 factor (p = 0.5). However, the ratio K2/PSR was shown to be a strong discriminating factor between the two groups of lesions (p < 10-3). For rCBV and rCBF indicators, high values of ROC AUC were obtained (> 0.9) and mean value thresholds were observed at 1.07 and 1.03, respectively. For K2/PSR in the reduced area, AUC was also superior to 0.9. CONCLUSIONS: The implementation of a dynamic T2* perfusion sequence provided reliable results using an objective whole-lesion ROI. Perfusion parameters as well as a new permeability indicator could efficiently discriminate high-grade from low-grade lesions in the pediatric population.

[Atypical intradermal smooth-muscle neoplasm]. / Tumeur musculaire lisse atypique dermique.

BACKGROUND: We report herein a case of atypical intradermal smooth-muscle neoplasm. PATIENT AND METHODS: A 58-year-old man presented with a painless pinkish-white chest nodule ongoing for two years. Histopathology revealed a proliferation of intradermal smooth-muscle cells. Some atypia and 5 mitoses were seen in the most mitotic fields. The histopathologist suggested a diagnosis of "atypical intradermal smooth-muscle neoplasm". DISCUSSION: Atypical intradermal smooth-muscle neoplasm is part of a spectrum extending from skin leiomyoma to leiomyosarcoma. The prognosis consists chiefly in risk of local recurrence. The terminology is not currently accepted by WHO but nevertheless offers an alternative to inappropriate diagnosis of sarcoma, which carries psychological and social impact.

Vascular expression of annexin A2 in lupus nephritis.

AIMS: To evaluate vascular expression of annexin A2 (ANXA2) and its subunit S100A10 in lupus nephritis (LN). METHODS: The present histological study included 14 patients with LN and 11 controls (patients with non-lupus kidney diseases). Kidney biopsies from patients with lupus were scored for lupus glomerulonephritis (according to the International Society of Nephrology/Renal Pathology Society 2003 classification) and vascular lesions (such as microthrombi and antiphospholipid syndrome nephropathy (APSN)). ANXA2 and S100A10 expression in glomerular and peritubular capillaries was evaluated by immunohistochemistry on tissue sections. The staining intensity score ranged from 0 (no expression) to 4 (intense expression). RESULTS: In patients with LN, the median age (range) at first kidney biopsy was 36 (18-49). Vascular lesions were observed in six patients (including two with APSN). We observed intense expression of ANXA2 in glomerular and peritubular capillaries while expression of S100A10 was weaker. However, one of the patients with APSN showed strong S100A10 expression. Patients with LN and controls differed significantly in terms of S100A10 expression in peritubular capillaries. We also observed a statistical difference between patients who had LN with renal vascular lesions and those without renal vascular lesions in terms of ANXA2 expression in peritubular capillaries. CONCLUSIONS: The presence of vascular lesions in LN appears to be associated with significant differences in the vascular expression of ANXA2. Vascular expression of ANXA2 was somewhat higher in LN. Vascular expression of S100A10 was somewhat lower in LN (except one of the two patients with APSN). Further studies of ANXA2's putative value as a biomarker of active LN or of vascular lesions in LN are required.