Is taTME delivering?

Excerpt

The first rectal cancer excision was attributed to Jacques Lisfranc who performed the operation through a transanal approach, as was the custom of the day in the 1800s [1]. The transanal approach was further developed by Richard von Volkmann a few decades later [2]. Nowadays, the unfortunate state of affairs is that advancement in a career is no longer supported by the premise that crediting the founding fathers and doing justice to the literature has meaning. In that regard, transanal total mesorectal excision (taTME) seems to be grabbing the headlines. The rationale behind taTME steams from a reasonable concern for involved circumferential margins and incomplete quality of TME in obese males with low rectal cancer and bulky mesorectum in a narrow pelvis (MOL). Although the literature in the English language does not provide evidence to back up the abovementioned concern for suboptimal oncologic metrics in MOL, the study by Targarona et al. [3] brought to everybody’s attention how the promontory-subsacrum angle of an android pelvis can affect oncological metrics when the resection is carried out laparoscopically. In fact, the shortcomings of a laparoscopic access to pelvic dissection for rectal cancer have been confirmed by two recent randomized control trials (RCT) (ACOSOG Z6051 and ALaCart), which concluded that laparoscopic resection is inferior to open surgery [4, 5]. The main reason to trust these two RCTs has much more to do with the choice of histopathology endpoints (circumferential resection margin (CRM) and complete quality of TME) than with their random order design. In fact, two other RCTs (COLOR 2 and COREAN) concluded that laparoscopic resection is non-inferior to open surgery based on survival rates, which as known are influenced by multiple factors (gene mutations, chemoradiation, etc.) and do not necessarily reflects the quality of surgery [4, 5]. As it is unlikely that the results of the ACOSOG Z6051 and the ALaCart trials will bring us back to open surgery, one could speculate that the same results may indirectly turn the light onto robotic-assisted resection. In fact, a matched comparison of the first 20 robotic cases by the same surgeon showed that the width of the CRM was significantly improved (open 8 mm vs. laparoscopic 4 mm vs. robotic 10.5 mm; p = 0.02) despite the learning curve [6]. A reasonable explanation seems to be that laparoscopic proctectomy may decrease the width of the CRM as a result of its restricted range of motion leading to a coning effect, which would be minimized by the improved ergonomics of the robotic wristed instruments [5]. The study by Barnajian et al. also concluded that the lack of tactile feedback did not adversely impact the quality of TME in the robotic cases [6]. Similarly, a pilot RCT had previously found no difference in TME quality comparing robotic to laparoscopic proctectomy [7]. …