Effect of force on ablation depth for a XeCl excimer laser beam delivered by an optical fiber in contact with arterial tissue under saline

The effect of force applied to a 430 micron single fiber, delivering 60 pulses of 308 nm XeCl laser radiation at 20 Hz, on the ablation depth in porcine aortic tissue under saline has been investigated. Energy densities of 8, 15, 25, 28, 31, 37, and 45 mJ/mm2 were used. Force was applied by adding weights from 0 to 10 grams to the fiber. The fiber penetration was monitored by means of a position transducer. At 0 grams, the ablation depth increased linearly with incident energy density, but the fiber did not penetrate the tissue; with any weight added, the fiber penetrated the tissue at energy densities above 15 mJ/mm2. The fiber did not penetrate during the first several pulses, possibly due to gas trapped under the fiber. After these first pulses, a smooth linear advancement of the fiber began, which lasted until the pulse train stopped. The ablation depth increased with increasing energy densities and weights. This effect was largest above 25 mJ/mm2 where the ablation efficiencies (unit mm3/J), with weights added to the fiber, were substantially larger than values found in 308 nm ablation experiments described in the literature, which were conducted with either a focused laser beam or a fiber without additional force. The results imply that in 308 nm excimer laser angioplasty, force must be applied to the beam delivery catheter for efficient recanalization, and that experiments performed with a focused beam or without actual penetration of the fiber do not represent the situation encountered in excimer laser angioplast

Extraskeletal osteosarcoma of the orbit: A clinicopathologic case report and review of literature

Primary extraskeletal osteosarcoma (EOS) is an extremely rare malignancy. In this report, the clinical course of a 32-year-old man presenting with proptoses is described. Medical history included Hirschsprung disease (HD), horseshoe kidney, azoospermia, and vertebral anomalies. Imaging of the orbit showed an oval, well-defined heterogeneous mass adjacent to the lateral wall of the orbit. The patient underwent a lateral orbitotomy and complete excision of the mass. The mass was not attached to the bone. Histopathologic and immunohistochemical examination confirmed the diagnosis of an EOS. The patient received chemotherapy and radiotherapy and is free of the disease 3 years after the diagnosis. Genetic screening showed no mutations for both the RET proto-oncogene for HD and the p53 tumor suppressor gene for osteosarcoma

The secretory small GTPase Rab27B regulates invasive tumor growth and metastasis through extracellular heat shock protein 90 alpha

Abstract Background: Vesicle exocytosis, controlled by secretory GTPases such as Rab27B, delivers critical pro-invasive factors into the tumor microenvironment. The biological role and expression status of Rab27B in breast cancer was unknown.Methods: Rab27B was studied in human breast cancer cells (MCF-7, T47D, ZR75.1) using GFP-fusion constructs, including Rab27A and Rab27B point mutants defective in GTP-binding or geranylgeranylation. In cell culture, cell-cycle progression was evaluated by flow cytometry and Western blotting, invasion was assessed using Matrigel and collagen type I substrates. Orthotopic tumor growth, local invasion and metastasis were analyzed in mouse xenograft models. Mass spectrometry was performed to identify Rab27B-secreted pro-invasive factors. Rab27B levels in clinical breast cancer were analyzed by quantitative reverse transcription-polymerase chain reaction (n=20) and immunohistochemistry (n=60). Statistical tests were two-sided.Results: Rab27B-upregulation promoted G1/S phase cell cycle transition, F-actin reorganization and invasion in cell culture, and invasive tumor growth and peritoneal metastasis in a xenograft mouse model (at 10 weeks, survival of MCF-7 GFP vs GFP-Rab27B injected mice was 100% vs 62.5%, P=0.0307). Proteomic analysis of purified Rab27B-secretory vesicles and the secretome of Rab27B-expressing breast cancer cells identified heat shock protein (HSP)90α as key pro-invasive factor. HSP90α secretion occurred in a Rab27B-dependent manner and was required for matrix metalloproteinase-2 activation. All Rab27B-mediated functional responses were GTP- and geranylgeranyl-dependent. In clinical samples, upregulation of endogenous Rab27B mRNA and protein correlated with lymph node metastasis (P=0.0002) and differentiation grade (P=0.0014) in estrogen receptor (ER)-positive human breast tumors.Conclusions: Rab27B, a new prognostic marker for ER-positive breast cancer, regulates invasive growth and metastasis. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6144.</jats:p

Unequivocal delineation of clinicogenetic subgroups and development of a new model for improved outcome prediction in neuroblastoma

PURPOSE: Neuroblastoma is a genetically heterogeneous pediatric tumor with a remarkably variable clinical behavior ranging from widely disseminated disease to spontaneous regression. In this study, we aimed for comprehensive genetic subgroup discovery and assessment of independent prognostic markers based on genome-wide aberrations detected by comparative genomic hybridization (CGH). MATERIALS AND METHODS: Published CGH data from 231 primary untreated neuroblastomas were converted to a digitized format suitable for global data mining, subgroup discovery, and multivariate survival analyses. RESULTS: In contrast to previous reports, which included only a few genetic parameters, we present here for the first time a strategy that allows unbiased evaluation of all genetic imbalances detected by CGH. The presented approach firmly established the existence of three different clinicogenetic subgroups and indicated that chromosome 17 status and tumor stage were the only independent significant predictors for patient outcome. Important new findings were: (1) a normal chromosome 17 status as a delineator of a subgroup of presumed favorable-stage tumors with highly increased risk; (2) the recognition of a survivor signature conferring 100% 5-year survival for stage 1, 2, and 4S tumors presenting with whole chromosome 17 gain; and (3) the identification of 3p deletion as a hallmark of older age at diagnosis. CONCLUSION: We propose a new regression model for improved patient outcome prediction, incorporating tumor stage, chromosome 17, and amplification/deletion status. These findings may prove highly valuable with respect to more reliable risk assessment, evaluation of clinical results, and optimization of current treatment protocols

Molecular test algorithms for breast tumours

In order to advise the Federal Government on all matters related to personalised medicine in oncology, including the reimbursement of molecular tests, the Commission of Personalized Medicine (ComPerMed) has applied, for the breast tumours, the same methodology as previously applied for the digestive tumours. Meaning, the different molecular tests, represented in the shape of algorithms, are annotated with test levels — which aim to reflect their relevance based on current available data and to define the reimbursement — and are documented with recent literature, guidelines and a brief technical&nbsp;description.</p