When the tumour sits very low: what a 2026 review says about sphincter-preserving surgery for rectal cancer
For rectal cancers very close to the anus, the hardest surgical question is whether the muscle that gives you control — the sphincter — can be kept, or whether removing it (and living with a permanent colostomy) is the safer way to clear the cancer. A 2026 narrative review surveys six sphincter-preserving techniques: most reach acceptable cancer-control outcomes, but bowel function afterwards stays the main concern, and the newest method rests on small studies. This is a survey of options, not a ranking — and the right answer is individual.
Treatment for rectal cancer often means surgery to remove the affected section of bowel, and depending on the operation that can involve a stoma — an opening in the abdomen through which waste passes into a pouch — which may be temporary or permanent [1]. A colostomy specifically diverts stool from the colon into a pouch worn on the outside of the body, and the NHS notes it can be either temporary or permanent [2]. For many people facing this surgery, the question underneath the medical question is simpler and more personal: will I be able to go to the toilet the normal way afterwards, or will I have a permanent bag?
That outcome turns, more than anything, on where the tumour sits. A 2026 narrative review in Frontiers in Gastroenterology focuses on the hardest version of this problem: ultra-low rectal cancer — a tumour very close to the anal verge, typically within about 3 cm of the proximal end of the anal dentate line. The review explains that this location makes it difficult to achieve the clear surgical margins needed to control the cancer locally while also preserving sphincter function — the muscle control that keeps continence and guards against faecal incontinence [3]. Two goals pull against each other: take enough tissue to be confident the cancer is gone, and keep enough to keep normal control.
Sphincter-preserving surgery is the umbrella term for operations that aim to remove the cancer without removing the anal sphincter — the alternative being surgery that takes the sphincter and therefore needs a permanent colostomy. The review surveys six such techniques: local excision; low anterior resection (with or without a prophylactic ileostomy or ileal stent); intersphincteric resection (ISR); the modified Bacon and Parks procedures; transanal total mesorectal excision (TaTME); and a newer approach called NOSES-PPS [4]. The names matter less than the shared aim: each is a different route to the same hope — clearing the tumour while keeping the body's own plumbing.
Here the review is careful, and we should be too. It is a narrative review — a survey and synthesis of the existing literature, not a head-to-head trial that ranks one technique above another. Its headline read is measured: most of these approaches achieve satisfactory oncological outcomes — meaning the cancer-control results are generally acceptable — but postoperative anal function remains a major concern [5]. In other words, keeping the sphincter is not the same as guaranteeing it works perfectly afterwards; bowel function can still be affected, and that trade-off is part of the honest picture.
The review singles out the newest technique, NOSES-PPS, as promising on function — preliminary evidence suggests it may help preserve anal function — but immediately tempers it: current studies are limited by small sample sizes and a lack of large-scale trials [6]. That is the right weight to give an early finding: a reason for cautious interest, not a reason to ask for a specific operation by name. And across all of the options, the authors conclude that optimal outcomes depend on patient selection, surgical expertise, and perioperative management [7] — which is to say the operation is only one part of it; who is operating, on whom, and the care around the surgery matter just as much.
If you are reading this because a low rectal cancer is on your own horizon, the useful takeaway isn't a technique to request. It's that sphincter preservation is often possible, that it is not automatic, and that the choice between keeping the sphincter and accepting a permanent colostomy is a genuine clinical judgement — balanced on the tumour's position, the margins, your overall health, and what good function would realistically look like for you. Those are exactly the questions worth bringing to your colorectal surgeon and stoma care team: what is achievable in your case, what the function trade-offs are, and what would change the plan. A review can map the options; only your own team can apply them to you — and that conversation is the one this kind of evidence is meant to support, not replace.