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BACKGROUND & AIMS The chromosome region 18q21 has been shown to be frequently deleted in colorectal cancers , and such frequent allelic loss is a hallmark of the presence of a tumor - suppressor gene .
 Disease: colorectal cancers
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease 
Text: {0} 
Answer:
 Disease: colorectal cancers