History of total mesorectal excision from Heald to nowadays

Résumé du document

Before TME was described by William Heald, most recurrences of rectal cancer were anastomotic, or centropelvic and anterior, probably related to incomplete resection of mesorectal fatty tissue. Nowadays, since the use of combined treatments, lateral and posterior forms appear more often. However, a pelvic CT scan study of 100 patients with recurrence after TME for rectal adenocarcinoma showed that mesorectal residua can be detected in up to 50% of cases; underscoring the fact that suboptimal proctectomy was still being performed in the era of TME.

Many studies have shown that surgery is beneficial for LR but these studies combined extra- and intraluminal recurrences including isolated anastomotic line recurrence after resection with sphincter preservation, where treatment gives much better carcinologic results (iterative anterior resection and colo anal anastomosis or APR) compared with extraluminal recurrence.
When recurrence occurs with an extraluminal component, the different planes of dissection such as the mesorectum and fascia recti, normally well individualizable, have completely disappeared, leading to tumor cell dissemination in a non-anatomical plane, and rendering dissection delicate if not impossible. When dissemination is no longer limited by the fascia, the number of recurrence loci increases within the pelvis and consequently, the number of organs and structures involved as well. The number of invaded pelvic sites appears to be a predictive factor for overall and disease-free survival and the presence of at least two pelvic fixation points (anterior, posterior or lateral) represents a pejorative prognostic factor.

Extraits

[...] History of total mesorectal excision from Heald to nowadays Before TME was described by William Heald, most recurrences of rectal cancer were anastomotic, or centropelvic and anterior, probably related to incomplete resection of mesorectal fatty tissue. Nowadays, since the use of combined treatments, lateral and posterior forms appear more often. However, a pelvic CT scan study of 100 patients with recurrence after TME for rectal adenocarcinoma showed that mesorectal residua can be detected in up to 50% of cases; underscoring the fact that suboptimal proctectomy was still being performed in the era of TME. [...]

[...] Only 10 in of neighborhood organs are histologically invaded. Patients are sometimes misclassified on preoperative imaging. In fact, postoperative anatomic modifications of the pelvis are the result of several factors including the initial type of surgery, a history of pelvic sepsis (anastomotic coloanal or colorectal fistula, abscess, pelvic peritonitis) and antecedent radiation therapy. Postoperative sequelae can render radiological interpretation difficult; when findings are mistaken for recurrence, intraoperative findings do not allow for the difference between fibrosis and recurrence, this can lead to excessive excision. [...]

[...] 2003;34(2-3):129- Reerink Mulder NH, Botke et al. Treatment of locally recurrent rectal cancer, results and prognostic factors. Eur J Surg Oncol nov;30(9):954- Wanebo HJ, Antoniuk Koness RJ, et al. Pelvic resection of recurrent rectal cancer: technical considerations and outcomes. Dis Colon Rectum. 1999;42(11):1438- Ferenschild FTJ, Vermaas Verhoef et al. Abdominosacral resection for locally advanced and recurrent rectal cancer. Br J Surg nov;96(11):1341-7. [...]

[...] and that of the Dutch National Referral Center were unable to show any real specific benefit to the addition of intraoperative radiation and this modality is associated with more post-operative complications compared with patients undergoing preoperative external radiation alone and the incidence of neuropathy after intraoperative radiation ranges from 10 to 30% depending on the dose delivered (the risk is higher when the dose is more than 15 Grays). In agreement with the data of the literature (to enhance LSM when expected to be less than 2mm), patients were selected in our study for IORT and could achieved curative resection. References 1. Heald RJ, Ryall RD. Recurrence and survival after total mesorectal excision for rectal cancer. [...]

[...] There are two particular aspects to pelvic sidewall involvement: hypogastric LN involvement or lateral extension of centropelvic LR. The smaller LSM is in this case is related to anatomic structures (sacral nerve roots, sciatic nerve, rigid bony frame) that limit the possibilities of curative resection. Faced with lateral extension, resection can be extended further laterally by extravascular dissection that sacrifices the hypogastric vessels and removes the adjacent cellular and fatty tissues. Once this interface is removed, dissection can be pursued in a virgin plane, in contact with the sacral nerve roots and obturator fascias, to obtain more optimal lateral resection margins. [...]