Comments on Levic et al.: The outcome of rectal cancer after early salvage TME following TEM compared with primary TME: a case-matched study

We have read with great interest the recent paper by Levic et al. [ 1 ], who compared, in a case-matched study, the outcomes of patients undergoing early salvage total mes- orectal excision (TME) following transanal endoscopic microsurgery (TEM) or primary TME for rectal cancer. They concluded that in selected patients, TEM can be chosen as a primary treatment modality, since subsequent abdominal rectal resection combined with TME did not compromise the outcome. TEM alone is an effective surgical treatment for T1 sm1 rectal cancers only [ 2 , 3 ], while TEM following neoadju- vant chemoradiation could be considered for more advanced rectal cancer [ 4 ]. However, Levic and colleagues included in their analysis both early (stage I) and locally advanced rectal cancers (stage II) that were treated with curative intent by TEM without neoadjuvant treatment. The interpretation of the results presented by the authors is biased by the fact that the groups were matched according to several variables, including the type of surgery per- formed, and therefore, the risk of abdominoperineal resection (APR) after failure of transanal local excision for rectal cancer, as reported in the literature, was underesti- mated. Recently, our group [ 5 ] clearly stated that laparoscopic TME after TEM is associated with a signifi- cantly higher risk of APR than primary TME. A full thickness TEM causes the development of a fibrotic scar, making the dissection of the correct planes down to the pelvic floor much more challenging even under clear and magnified laparoscopic vision, and sometimes making a low colorectal or a transanal coloanal anastomosis techni- cally impossible. Further, large prospective series are needed to evaluate the risk of APR in selected rectal cancer patients treated with salvage TME in case of failure of transanal local excision (i.e., TEM)