Adenoma residua in colorectal cancer. A study of 34 colorectal cancers detected by an immunological occult blood test.

A retrospective histological study was made searching for adenoma remnants in 34 colorectal cancer specimens detected by the quantitative and human Hb-specific immunological FECA-EIA test for occult blood in the faeces. As a control group, 34 colorectal cancer preparations from routine hospital material were studied in a similar manner. A difference was found between these materials, 12 out of 34 study cancers showing adenoma residua compared with only two in the control group. Even if a proportion of colorectal cancers is apparently not associated with adenomas, it is suggested that the existence of adenoma remnants is a sign of biologically early tumour development and consequently, it might correlate with a favourable prognosis.