How Can One Understand the Changing Diagnostic Terminologies

Time and space do not permit us to answer this question! The only safe method is to ask the other persons what terminology they are using and try to work out a mutually satisfactory translation! One may refer to books already in print on tumors [4,5,6,7,8] and other diseases [10], but one must remember that these were probably out of date before they were published! The classifications and terminologies on tumors are especially numerous, complicated and controversial, particularly when considering gliomas. The logical difficulties are circular: without knowing the histological variations, one cannot tabulate the biological variables. Even though there are some strange compromises that provoke continuing criticisms, the current World Health Organization's classification should be supported as an heroic attempt to standardize terminologies internationally -with all the inherent biases of international relations considered - since this approach is likely to be far more advantageous in the long run. In the mean time, a comment comparing other terminologies is frequently necessary.

As for the future, at least one of us believes that the ultimate resolution lies in actually measuring the growth rates and degree of infiltration to truly define high, intermediate or low grades and to suggest the probable degree of resection that should be attempted. The past behavior should predict the future at least sufficiently accurately to suggest when the next follow-up scans should be obtained and how frequently thereafter, thus providing some estimate of how effective the therapy has been in that particular patient [11,12]. Figure 3.22 illustrates the growth of the average diameter linearly with time, a pattern typical of infiltrating gliomas of low and high grade, the velocities differing by a factor of 10, each extreme being an average of +50%, as estimated by Woodward et al. [13]. By contrast, constant volume-doubling times are typical of the exponential growth of solid tumors (Fig. 3.23). Over short periods of time the proof of one mathematical formula or the other may be difficult clinically, but the difference over long periods of time is really quite striking (Fig. 3.23). The biological difference relates to the subclinical and more or less sub-microscopic, invisible, infiltrating cells that convert the "edge" of the detectable tumor into a "travelling wave" that expands linearly with time rather than exponentially, as occurs if there is no external diffusion of cells.

When all is said and done, there are only a few gliomas that are susceptible to total resection: cerebellar astrocytomas and PXAs. In these cases, frozen section studies of the "margins" should be useful, and the surgeon should be tempted into resecting more than the gross may suggest, without, of course, increasing the patient's disability.

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Cure Your Yeast Infection For Good

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