Further Study on Field Cancerization in the Human Colon

Nearly 70 years ago, Slaughter launched the hypothesis of field cancerization for oral carcinomas; that hypothesis was subsequently also claimed for carcinomas in other organs. We previously found in the colon mucosa adjacent to nonpolypoid adenomas, branching crypts lined by normal epithelium (BCNE). Here, we explored whether BCNE could also be found in the colon mucosa adjacent to sporadic polypoid tubular adenomas (TA), the most prevalent of all colon adenomas.

Nondysplastic mucosa adjacent to TA was found in 103 out of 131 TA. All BCNE adjacent to TA were recorded.

In 98 (95.1%) out of 103 TA having nondysplastic adjacent mucosa, 645 BCNE were registered: 82.6% were in asymmetric branching and 17.4% in symmetric branching. Thus, BCNE in asymmetric branching predominated. The frequency of BCNE adjacent to TA was influenced by the adenoma size and degree of dysplasia severity. Contrarywise, the frequency of BCNE adjacent to TA was neither influenced by the age or sex of the patients, nor by the colon localization of TA.

BCNE often occur in the normal mucosa adjacent to TA. BCNE emerge as integral components of TA. The majority of the BCNE were in asymmetric branching, considered as aberrations of cryptogenesis. We propose that the accretion of asymmetric BCNE adjacent to TA supports Slaughter's hypothesis of field cancerization.