Another thought. If you decide on rectal resection, there is recent literature indicating a technique to reduce the risk of ending up with LAR syndrome:
Functional results after treatment for rectal cancer
J COLOPROCTOL. 2014; 34(1): 55 – 61
http://www.scielo.br/pdf/jcol/v34n1/2237-9363-jcol-34-01-00055.pdfI wish I had read it before my surgery (actually, the article didn't exist yet.) On page 58 is the key thing to discuss with your doctor before surgery:
Recently, a study showed that careful preservation of the
colonic and pelvic nerves can result in less fragmentation of
stools. In high ligation of the inferior mesenteric artery and
dissection of the lymph nodes close to the aorta, the extrinsic
autonomic sympathetic nerves to the rectum and left side of
the colon are resected, causing a sympathetically denervated
colonic segment used for creation of the neorectum. This
has been suggested to be a major cause of stool fragmentation,
due to the missing negative feedback of the defecation
reflex, causing an urge to defecate even when only small
amounts of stools are present in the neorectum. Therefore,
it has been suggested that resection with preservation of the
left colonic artery might preserve autonomic function without
compromising oncological outcome.
Stool fragmentation is the major bugaboo of LAR syndrome. When it happens, the urge to go continues for an hour or more after first starting. Small stools continue to come out very slowly and there's no way to stop it. If the surgeon can protect these nerves, it may prevent the syndrome.