The present invention, in one aspect, relates to a method of and apparatus for examining a target for tumors or lesions using what is referred to as "Early Increase in microvascular Blood Supply" (EIBS) that exists in tissues that are close to, but are not themselves, the abnormal tissue and in tissues that precede the development of such lesions or tumors. While the abnormal tissue can be a lesion or tumor, the abnofmal tissue can also be tissue that precedes formation of a lesion or tumor, such as a precancerous adenoma, aberrant crypt foci, tissues that precede the development of dysplastic lesions that themselves do not yet exhibit dysplastic phenotype, and tissues in the vicinity of these lesions or pre-dysplastic tissues.