Vascular morphology, tumors

In addition to differences between tumors and their environment, the neo vascular phenotype itself may differ between tissues. A variety of vascular morphologies has been discussed above, and specific molecules expressed by the neovasculature may also vary. For example, binding of the antiangiogenic factor endostatin was found to almost all bladder tumor vessels, three quarters of the vessels in prostatic carcinomas, and only 11% of renal tumor vessels [63]. VEGFR3, which, in most tissues, is restricted to lymphatics, has been identified in the new blood vessels of inflamed synovium [26]. These and other characteristics of different neo vascular beds may contribute to heterogeneous responses to therapies that target the vasculature. 

Aggressive angiomyxoma (AAM) is a peculiar neoplasm of the pelvic and perineal soft tissues that most commonly affects women. It is composed of loosely arranged, bland spindled to stellate cells embedded in a myxoid matrix punctuated by numerous venule- and capillary-sized blood vessels reminiscent of myxoid liposarcoma (Fig. 4.8). The vascular pattern of AAM lacks the arborizing appearance that is seen in some overtly malignant myxoid tumors. Some morphologic and immunophenotypic features of aggressive AAM also are shared in part by intramuscular myxoma. 

Convection of heat via blood depends primarily on the local blood flow in the tissue and the vascular morphology of the tissue. Thermal diffusion is determined by thermal conductivity in the steady state, and thermal diffusivity in the unsteady state. In addition to these transport parameters, we need to know the volumes and geometry of normal tissues and tumor. In general, tumor volume changes as a function of time more rapidly than normal tissue volume. In special applications, such as hyperthermia induced by electromagnetic waves or radiofrequency currents, we need electromagnetic properties of tissues—the electrical conductivity and the relative dielectric constant. In the case of ultrasonic heating, we need to specify the acoustic properties of the tissue—velocity of sound and attenuation (or absorption) coefficient. 

Within the vasculature of a tissue, blood flows in all directions, and the local direction of convection depends on the vascular morphology of the tissue. The situation is even more complex in tumors where the direction and magnitude of blood flow are not fixed. In tumors, blood flow is temporally and spatially inhomogeneous. Therefore, the local description of convective heat transfer term, Qb, in tissues would include a time-dependent velocity vector — a problem which is enormously complex and has thus far proven mathematically intractable. In order to circumvent a mathematical description of the details and complexities of the microcirculation in a capillary bed, primarily two approaches have been taken by investigators in this area of research (Charny, 1992). 

The increased uptake of PKl in smaller tumors (expressed as % dose/g) (194) (Fig. 12b), and the observation that maximum PKl extravasation occurs in the tumor periphery where angiogenesis is taking place (196), posed the question, Would vascular morphology, vascular permeability. 

Warren BA (1979) The vascular morphology of tumors. In Peterson H-I (ed) Tumor Blood Circulation Angiogenesis, Vascular Morphology and Blood Flow of Experimental Human Tumors CRC Press, Florida, pp. 1-47. 

Some new materials perspective for advanced biomedical technologies, especially carbon nanoparticles like fullerenes, are potentially mutagenic, carcinogenic and immunogenic [16,65], Therefore, standard tests of the morphological transformation of Syrian hamster embryonic cells in cultures on these materials (described in detail by [68,69]) can be performed. Immune activation of bone and vascular cells on the materials can be estimated by increased concentration of immunoglobulin and selectin adhesion molecules (ICAM-1, VCAM-1, ELAM-1), which bind cells of the immune system [15,16,18,19,23], as well as by the production of cytokines, such as tumor necrosis factor alpha or interleukins beta [55],... 

Yilmaz A, Bieler G, Spertini O, Lejeune FL, Ruegg C. Pulse treatment of human vascular endothelial cells with high doses of tumor necrosis factor and interferon-gamma results in simultaneous synergistic and reversible effects on proliferation and morphology. Int J Cancer 1998 77 592-599. 

This tumor is the most common neuroendocrine neoplasm of the larynx and accounts for approximately 54% of all tumors.1 " It occurs most frequently in the supraglottic larynx and has a male predominance. Atypical carcinoids have an infiltrative growth and can have variety of morphologic patterns. The cells differ from those of a typical carcinoid in that they are larger and show nucleoli and occasional mitoses. Furthermore, they may exhibit necrosis and vascular or perineural... 

Perhaps because of the wide spectrum of morphologic images associated with vascular tumors of the skin, a great deal of attention has been paid to their immuno-... 

Aspects on the synthesis of polymers with a core-shell structure obtained from suspension polymerization, which is used in vascular embolization, are described elsewhere [3,12,13]. In this scenario the synthesis of polymer/inorganic hybrids has also been exemplified by our research group [14,15]. As a representative example of embolic agents, magnetic copolymers of poly(vinyl acetate) (PVAc)/poly(vinyl alcohol) (PVA) with a core-shell structure have high potential for the treatment of tumors and hyperthermia therapy of injured areas. The implementation of this process is possible by adhering superior control of the reaction system, which will produce particles of similar morphology comparable to the substance precursor. 

Dual phase, contrast-enhanced MRI with perfusion sequence will not only delineate the extent and viability of tumor but also serve as a baseline study to plan future treatment. A simple dual-phase MRI or CT is acceptable as well but inferior to MRI perfusion in quantifying viable tumor. In addition to information regarding tumor viability and morphology, cross-sectional provides information regarding the tumor s vascular supply and anatomy. For example, knowing the presence of portal vein thrombosis... 

Score Tumor morphology Child- Pugh AFP Vascular invasion... 

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