Is sphincter preservation in low rectal cancer facilitated by preoperative chemoradiation and intersphincteric dissection?
In low rectal cancer, sphincter preservation is facilitated by a significant response to preoperative chemoradiation and intersphincteric resection, without compromise of margins or outcome. In those who have a less favorable response, abdominoperineal resection is more likely to be required and is associated with poorer outcome.
We present the very first framework for measuring the fraction of the relevant genetic history of a population that is mathematically elusive. Our observed results on the tested demographies suggest that it may be better to aggregate the analysis of smaller chunks of chromosomal segments than fewer large chunks. Also, no matter the richness of samples in a population, at least one-third of the population genetic history is impenetrable. The framework also opens up possible new lines of investigation along the following. Given the characteristics of a population, possibly derived from observed extant individuals, to estimate the (1) optimal sample size and (2) optimal sequence length for the most informative analysis.