An unusual case of melanoma metastasis in the buccal space: learning by mistakes to distinguish it from salivary neoplasms.

BACKGROUND: The buccal space is an unusual location of malignancies. We report here the case of a woman with a melanoma metastasis in buccal fat pad, to evaluate the imaging features which might lead to the correct, although uncommon, diagnosis. CASE PRESENTATION: A 71-year-old woman presented with a painless visible swelling of the left cheek. MRI revealed the presence of a solid lesion located in the buccal fat pad with features suggestive of malignancy. It showed T1 hyperintensity and T2 hypointensity, and restriction of diffusion. Histological examination showed neoplastic cells compatible with melanoma. DISCUSSION: The lesion features (T1 hyperintensity and T2 hypointensity) initially lead our team to believe that there was a hemorrhagic component, possibly a residue of the biopsy. However, when associated with other malignancy features, such as low apparent diffusion coefficient (ADC) values and contrast enhancement, they should evoke the suspect of melanoma, provided that no biopsy was performed and no trauma occurred in the 3-7 days before.

New concepts in embolotherapy of HCC.

Hepatocellular carcinoma (HCC) is the second most common cause of cancer-related deaths worldwide with rapidly growing incidence rates in the USA and Europe. Despite improving surveillance programs, most patients are diagnosed at intermediate to advanced stages and are no longer amenable to curative therapies, such as ablation, surgical resection and liver transplantation. For such patients, catheter-based image-guided embolotherapies such as transarterial chemoembolization (TACE) represent the standard of care and mainstay therapy, as recommended and endorsed by a variety of national guidelines and staging systems. The main benefit of these therapies is explained by the preferentially arterial blood supply of liver tumors, which allows to deliver the anticancer therapy directly to the tumor-feeding artery while sparing the healthy hepatic tissue mainly supplied by the portal vein. The tool box of an interventional oncologist contains several different variants of transarterial treatment modalities. Ever since the first TACE more than 30 years ago, these techniques have been progressively refined, both with respect to drug delivery materials and with respect to angiographic micro-catheter and image-guidance technology, thus substantially improving therapeutic outcomes of HCC. This review will summarize the fundamental principles, technical and clinical data on the application of different embolotherapies, such as bland transarterial embolization, Lipiodol-based conventional transarterial chemoembolization as well as TACE with drug-eluting beads (DEB-TACE). Clinical data on 90Yttrium radioembolization as an emerging alternative, mostly applied for niche indications such as HCC with portal vein invasion, will be discussed. Furthermore, we will summarize the principle of HCC staging, patient allocation and response assessment in the setting of HCC embolotherapy. In addition, we will evaluate the role of cone-beam computed tomography as a novel intra-procedural image-guidance technology. Finally, this review will touch on new technical developments such as radiopaque, imageable DEBs and the rationale and role of combined systemic and locoregional therapies, mostly in combination with Sorafenib.

Coarsening effect on island-size scaling: the model case InAs/GaAs(001).

The distributions of the size of islands and of the capture zones are discussed comparatively, both experimentally and numerically, for the case of a sudden nucleation process with and without coarsening. The experiments were performed by growing InAs islands on GaAs(001) and the coarsening was altered by varying the temperature. In the two-dimensional kinetic Monte Carlo simulations a single-species diffusing adatom was taken into account, and the coarsening was altered in this case by modifying the binding energy between adatoms and islands. The results show that size and capture zone distributions overlap only when coarsening can be disregarded.

Comparative study of low temperature growth of InAs and InMnAs quantum dots.

The evolution of InAs and In(0.85)Mn(0.15)As quantum dots grown at 270 °C is studied as a function of coverage. We show that, in contrast to what occurs at high temperature, the two-dimensional to three-dimensional transition is not abrupt but rather slow. This is due to the finding that part of the deposited material also contributes to the wetting layer growth after quantum dot formation. This aspect is particularly accentuated in In(0.85)Mn(0.15)As deposition. The Voronoi area analysis reveals a significant spatial correlation between islands.