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Anatomically the supraglottic larynx has been shown to be self contained as regards its boundaries and lymphatic compartments which tend to limit the spread of cancer arising within the region until it reaches the margins of the supraglottis (Pressman and Simon, 1961). These may be called Type A tumours. Advanced glottic tumours secondarily involving the supraglottis may be considered a sub-group within the larynx (transglottic).
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H. J. Shaw (1988) studied this question.
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