Rectal Cancer

Surgery of rectal carcinoma is special and a great challenge to the surgeon. Two regions of interest meet here: first is the demand for a radical resection of the tumor; this often clashes with the desire to preserve the anal sphincter and thus normal continence for stool and quality of life.


The rectum serves as a reservoir for stool with the sphincter apparatus at its lower end. Sphincter and rectum facilitate controlled emptying of the bowel and /or the retention of stool. This continence function is based on the rather complicated physiological interaction of diverse sphincter components, the pelvic floor, the reservoir, diverse reflexes and sensors etc. In the past major components of the continence apparatus were removed during operations of rectal cancer because the surgeon believed this would increase radicality of the operation and survival of the patient. Only a few years ago an abdominoperineal operation (Miles operation) with complete excision of the anal sphincter was the standard procedure for low rectal cancers, which meant a permanent stoma for the rest of the patient’s life. Fortunately this has changed.


Preservation of the sphincter is one of the main goals of every ambitious surgeon today. This is possible in more than 90% of all patients with a rectal cancer. Of course this may not lead to abandoning standard resection and radicality criteria. Defined resection margins above, below and circumferential must be strictly respected in order to insure complete removal of the tumor and prevent local recurrence. This goal can be achieved with several techniques which I would like to discuss in the following.



Local Exision

In very early rectal cancer local excision of the tumor has the same survival rates as extensive resection. This is only feasible after exact staging of the tumor, i.e. exact determination of the tumor size, its invasion into the layers of the bowel wall and the exclusion of lymphatic spread. Careful clinical examination, endoluminal ultrasound and MRI provide the necessary information. When all the criteria are met, transanal excision of the tumor is possible. see figure



Total mesorectal excision (TME)


Loss of sexual function and problems with emptying of the urinary bladder due to damage of the autonomic nerves of the pelvis during dissection of the rectum are frequent and severe complications of rectal surgery. Especially sexual function is destroyed in 60-80% of patients with the traditional blunt dorsal dissection technique of the rectum. Thanks to the English surgeon, Mr. Bill Heald the technique of rectal dissection has become more anatomical and usually avoids damage to the nerves of the pelvis. The so called mesorectum is dissected sharply within its natural borders, thus preserving the nerves that run on the outside and the lymphatics of the mesorectum inside the border lamella. If these lymphatics are damaged, tumor cells could escape and implant in the pelvis leading to local recurrence of the tumor. Using the technique of total mesorectal excision right down to the pelvic floor ensures removal of lymph nodes below the level of the tumor. With this TME-technique Heald not only managed to improve functional results (bladder and sexual function) but also radicality. Heald’s local recurrence rates in rectal cancer of 2,7 % are way below the usual results. see figure


Low anastomosis


New and improved techniques of anastomosis have facilitated the preservation of the anal sphincter in rectal resection. Ultra low anastomosis can be performed with the help of staplers and with further development of transanal hand sown anastomosis. Continuity of the bowel is often restored by connecting the colon directly to the anus. In order to obtain better safety margins on the specimen even the upper parts of the sphincter can be included in the resection (intersphincteric resection, coloanal anastomosis) without loss of continence. see figure 1 see figure 2



Neo rectum


Even though the development of low anastomotic techniques enabled us to avoid loss of the sphincter in most cases, functional results were not yet satisfactory. An increased stool frequency, urge or partial incontinence were disabling side effects of low resection and impaired quality of life. Several years ago surgeons started using colonic-reservoirs for the reconstruction following low rectal resections. A so called colonic pouch was created from the last part of the colon and connected to the anus. This pouch serves not only as reservoir but also slows down motility and stool passage and therefore reduces stool frequency significantly.


Temporary protective stoma


Creation of a temporary protective stoma is nearly always part of a resection of a low rectal cancer in order to insure healing of the anastomosis. This is necessary because of the very delicate blood supply in the lower rectum and the colon used for reconstruction, but also because of potential damage to pelvic tissue following preoperative radio chemotherapy. Of course one could gamble and hope for successful healing of the anastomosis without a stoma. The problem is that a leak in the anastomosis causes contamination of the pelvis with stool. This results not only in a life threatening inflammation (peritonitis), which now necessitates a stoma anyway, but also in a severe fibrosis of the pelvis, which destroys any reservoir function of the neo rectum. The patient ends up with very poor function and a massively increased stool frequency.


I use a protective stoma in all my patients with a low resection. The stoma is taken down 1-6 weeks after the operation. see figure



Neoadjuvant multi modality treatment


Carcinomas of the lower two thirds of the rectum increasingly undergo radiotherapy before the planned operation. The aim is to achieve a decrease in size of a tumor that may otherwise not be resected completely or that would necessitate the resection of the sphincter. In most cases this preoperative treatment is very successful and, as recent studies show, lead to a significant improvement not only of the prognosis, but also of the functional result. I prefer preoperative radio chemotherapy in all my patients with cancer in the lower two thirds of the rectum, except for very small tumors. The ambulant therapy takes about 5 weeks and is then followed by a recovery period of 4 weeks to enable the tissues to “cool down” before the operation. Before the operation the patient gets another CT scan and colonoscopy (restaging), to evaluate the effect of treatment so far. In most cases we see a significant decrease in size of the tumor which makes the operation a lot easier.