Tumour `budding' as an index to estimate the potential of aggressiveness in rectal cancer

AIMS: Although the characteristic of invasive pattern which contributes to Jass's classification is a sensitive prognostic marker in rectal cancer, reproducibility of its assessment has been shown to be problematic. As another histological parameter of invasive margin, we examined the prognostic significance of tumour 'budding' and attempted to establish its appropriate criteria. METHODS AND RESULTS: A total of 638 rectal cancer specimens was examined. We defined tumour 'budding' as an isolated single cancer cell or a cluster composed of fewer than five cancer cells. We divided these into two groups by their intensity, i.e. the number of 'budding' foci within a microscopic field of x 250. Rectal cancer with…