Quality of life after rectal cancer surgery: differences between laparoscopic and transanal total mesorectal excision

The short-to-medium term functional outcome data reported in our study, including anorectal function and quality of life, did not reveal any major differences between the transanal and laparoscopic TME groups. However, there were significant differences in quality of life favoring the laparoscopic approach to TME in terms of role functioning, fatigue, and financial difficulties. Role functioning, limitations in pursuing daily activities or leisure time activities, and fatigue can probably be attributed to differences in length of follow-up. Patients in the TaTME group had less postoperative recovery time, therefore worse outcome was reported. However, we could not attribute the difference in financial difficulties between the two groups to any specific cause.

The results of the EORTC QLQ-C29 questionnaire showed a significant difference between the two groups in terms of fecal incontinence scored by a single item regarding leakage of stools, favoring the LAR group. The questionnaire was mainly developed for quality of life evaluation, which includes some questions specific to function. Other outcomes regarding stool-related questions in this questionnaire and in the EORTC QLQ-C30 were similar between the groups. Differences in individual questions on function should therefore be addressed with caution, especially because no differences were seen in functional outcomes by the LARS questionnaire, which is developed specifically for anorectal function. Low Anterior Resection Syndrome was reported equally in both groups. Moreover, when analyzing the individual questions of the LARS questionnaire separately, including one regarding incontinence for liquid stool, again no significant differences were seen between the groups.

The functional outcomes reported in this study show that LARS symptoms occur with equal frequency in patients who underwent standard laparoscopy or those in whom TaTME was employed. These findings are comparable to reports in the literature. Long-term follow-up data from the Dutch TME trial showed that 46% of patients still endure major LARS symptoms as far out as 14 years after TME surgery [8]. A study by Pontallier et al. [19] reported severe symptoms after both transanal and laparoscopic approaches for low rectal cancer, with major LARS in 82 and 76% of the transanal and standard laparoscopy patients, respectively. A recently published study by Koedam et al. reported 33% major LARS in patients after TaTME [20]. While both studies showed significant LARS symptoms after transanal resection, their results cannot be compared because the two studies included different patient groups, with more distal tumors and intersphincteric resections in the Pontallier study [19].

Our study does not show any overall difference in urinary symptoms or sexual function. The study by Pontallier et al. [19] showed a trend towards better erectile function with a higher rate of sexual activity in the transanal group. This study suggests that the transanal approach allows better preservation of the pelvic nerves.

Our data suggest that functional results are comparable after transanal and laparoscopic TME, despite that we are still in the early phase of implementation of this technique. The transanal approach to TME is still developing into a standardized approach and may have enormous advantages over laparoscopic or open surgery. TaTME improves visualization of the surgical planes, which improves the quality of the surgical specimen and may reduce the need for conversion. We recently published short-term data on our first 80 patients, in which specimens were graded as complete or nearly complete in 97%. CRM positivity was seen in 2.5% of patients and the distal margin was free in all patients [2]. Since we first implemented transanal TME in 2012, the technique has evolved considerably. We initially worked with one team, starting transanally. We currently use a two-team approach, as advocated by Lacy and coworkers [21], wherein the splenic flexure is mobilized, followed by mobilization of the sigmoid and upper rectum by the abdominal team, while the transanal team simultaneously mobilizes the low and mid rectum [22]. Another significant change in protocol we introduced during the learning phase was the level of the proximal purse string suture. In our early experience, the purse string was often placed unnecessarily low. A better understanding of down-to-up anatomy led us to appreciate that low purse string sutures are often unnecessary, as the mesorectum frequently starts much higher than initially thought. Depending on the tumor location, the purse string is placed approximately four centimeters from the dentate linea, leaving ample space for a stapled side-to-end anastomosis.

Despite the shortcomings of TaTME as currently implemented, this approach to TME has afforded patients with low rectal cancer who have a narrow pelvic space, in which dissection and division of the rectum below the tumor has proven to be impossible, another alternative. Prior to the introduction of TaTME, these patients were often faced with an end colostomy because the procedure is generally converted to an intersphincteric dissection or even APR in order to allow dissection in the distal rectal region. TaTME has allowed patients who would previously only qualify for colostomy the option for a low anastomosis. Although TaTME may influence short-term functional results, the current data do not support this finding with comparable short-to-medium term outcomes between laparoscopic and transanal TME.

The comparison of consecutive groups in the current study, which resulted in differences in length of follow-up and small sample size, could be interpreted as a flaw in the study design. Unfortunately, the TaTME approach was employed at the end of the study period and became the preferred approach to TME, which did not allow comparison of the two techniques. Although it is generally accepted that functional results will stabilize over a period of time, this factor could have influenced the results.

All patients in the TaTME group were operated by a single surgeon in one hospital. Outcomes of this patient group could therefore have been influenced by a learning curve, as some included patients were one of the first in this hospital who underwent TaTME. Despite this possible learning curve, comparable functional and quality of life outcomes were measured in this study.

Another study limitation is the type of anastomosis employed since previous literature has proven that type of anastomosis could be of influence on functional outcome [23, 24]. Patients in the LAR group had a side-to-end anastomosis, while patients in the TaTME group had an end-to-end anastomosis. However, this difference is not expected to influence the results of our study since the type of anastomosis will only effect short-term functional outcomes and stabilizes after six months as results described in current data [23]. Although patient age also differed between the groups, we are not aware of any relation between age and function. Other patient characteristics known to be of influence on functional outcome such as tumor height and type of neoadjuvant were equally represented in both groups.