Evidence - Rectal resection, open, low anterior with total mesorectal excision (TME)

Definition of colon and rectal cancer

According to the international classification system, rectal carcinomas are tumors whose proximal margin is 16cm or less from the anocutaneous line when measured with rigid rectoscopy [1, 2]. A distinction is made between

• the inferior third (0-6cm),
• the middle third (6-12cm) and
• the superior third (12-16cm) [3].

In the USA, however, tumors up to 12cm from the anocutaneous line are referred to as rectal cancer, while those beyond the 12cm limit are classified as colon cancer [4].

Shortened TNM classification of colorectal carcinoma [5]

Tumor Board

Because of the complex therapy, all colorectal carcinomas should be presented to a tumor board prior to therapy (e.g., surgery, chemotherapy) to develop a joint treatment protocol. A study from the UK demonstrated a significant increase in patient survival when this regimen was followed [6].

A pretreatment board decision is particularly recommended in the following settings:

• All rectal cancers
• All stage IV colon cancers
• Distant metastases
• Local recurrences
• Before any local resection measures

In rectal cancer, for example, it can be evaluated if the patient should undergo neoadjuvant radiochemotherapy. In one study, pretherapeutic case conferences also significantly lowered the rate of tumor-positive resection margins in the surgical specimens [7]. In the presence of distant metastasis, it can be evaluated if palliation or ablation should be pursued, and whether distant metastases (e.g., liver metastases) should be resected synchronously or in a second procedure.  Patients with distant metastases who have initially undergone chemotherapy should be presented again to clarify whether secondary resectability of the metastases is given. Repeated presentation of patients in tumor boards has increased the rate of metastatic surgery [8].

Preoperative staging

Staging of rectal cancer comprises

• Complete colonoscopy, biopsy of any synchronous other tumors
• Abdominal ultrasonography
• Chest film
• Rigid rectoscopy, possibly with biopsy and measurement of distance to dentate line
• Pelvic MRI with measurement of distance between tumor and mesorectal fascia 
• Rectal endoluminal ultrasonography as alternative to MRI

Rectal digital examination is also mandatory (assessment of sphincter function, in low rectal cancer assessment of possible sphincter preservation).

 Synchronous other tumors can be expected in 5% of colorectal cancer. Therefore, complete colonoscopy should be performed before surgery [9, 10, 11]. If this is not possible because of a stenotic tumor, preoperative imaging modalities (CT or MR colonography) come into play [12]. In these cases, the patient should undergo colonoscopy 3–6 months after surgery, irrespective of the imaging modality originally employed.

In rectal cancer, the rate of distant metastasis at the time of initial diagnosis is 18%. 14% of the distant metastases are found in the liver, 4% in the lungs, 3% along the peritoneum, and 2% in nonregional lymph nodes. Basic work-up of liver metastases comprises abdominal ultrasonography and a CT study of the abdomen [13, 14].

At the time of initial diagnosis, the level of the tumor marker CEA is elevated in about 30% of all colorectal cancers and should therefore be determined preoperatively. In the follow-up of tumor marker expressing malignancies, the CEA level is a reliable indicator of recurrence, and in liver metastases also an independent prognostic factor. At present, the significance of CA 125 as a follow-up parameter in follow-up treatment of confirmed peritoneal metastasis is unclear [15, 16, 17].

Importance of local staging in rectal cancer

In rectal cancer, local staging plays a decisive role when planning further treatment:

For T3 carcinomas, data show that the extent of mesorectal invasion (especially the distance to the mesorectal fascia) is of major prognostic significance [18]. In total mesorectal excision (TME), this level represents the circumferential resection margin (CRM).  If the cancer spread in the mesorectum is to within 1mm of the fascia or has already invaded it (CRM+), the risk of local recurrence is significantly increased [18]. Another prognostic factor is lymph node involvement [19].

In a 2004 meta-analysis studying data on EUS, MRI and CT until 2002, EUS demonstrated the highest accuracy in T1 cancer [20]; this result was confirmed in a more recent meta-analysis [21]. An alternative to EUS is MRI with an endorectal coil (more expensive, uncomfortable for patients, hardly available). Compared to MRI and CT, EUS was more sensitive in the differentiation of T2 and T3 carcinomas [20], whereas in T4 cancer the various imaging modalities did not differ significantly. When visualizing the mesorectal fascia and its relations with the tumor, MRI has the highest sensitivity [22]. While spiral CT is an alternative for fascial assessment [23], EUS cannot visualize the fascia.

Radical surgery in rectal cancer

Curative radical resection of rectal cancer usually comprises complete resection of the primary tumor as well as partial or total resection of the mesorectum and thus of the regional lymphatics [24]. Curative resection by local measures (full-thickness resection) is only possible in selected cases fulfilling strict criteria.

If the criteria of oncologic surgery are met, the following surgical procedures can be regarded as equivalent, depending on the location of the tumor, relation with the dentate line and levator ani, depth of invasion, and sphincter function:

• Low anterior resection
• Abdominoperineal resection
• Intersphincteric resection (abdominoperanal resection)

Oncologic principles:

1. Removal of the regional lymphatics and division of the inferior mesenteric artery at least distal to the origin of the left colic artery. The value of lymph node dissection along the trunk of the inferior mesenteric artery proximal to the origin of the left colic artery is not known [25 - 28]. The same applies to the dissection of the lateral lymph nodes along the internal iliac artery and its branches [31 - 34].

2. Total mesorectal excision (TME) in cancer of the middle and inferior third of the rectum and partial mesorectal excision in cancer of the superior third of the rectum by sharp dissection between the visceral and parietal pelvic fasciae along anatomical structures [29, 30].

3. Ensuring an adequate safety margin

• Superior third of rectum: Horizontal division of the rectum with partial mesorectal excision 5cm distal to the gross edge of the tumor [29, 36-39] *
• Middle and inferior third of rectum: TME to the pelvic floor, sparing the superior hypogastric plexus, hypogastric nerves and inferior hypogastric plexus [40 - 42]

         -> Well or moderately differentiated low-grade tumor in the inferior third – safety margin of 1-2cm adequate

         -> In high-grade tumors > 2cm [43 - 47]

Reasons: In rare cases of T3 and T4 tumors, satellite nodes or lymph node metastases may be present up to 4cm distal to the gross tumor margin.

Reconstruction after total mesorectal excision

The following reconstruction techniques are possible in TME with subsequent juxta sphincteric anastomosis:

• End-to-end coloanal anastomosis
• Colonic J-pouch
• Transverse coloplasty
• Side-to-end anastomosis

Especially the end-to-end coloanal anastomoses lead to higher rates of bowel movement as well as worse fecal continence and quality of life, particularly in the first two years after surgery; for this reason, they are not recommended [48]. The benefits of the colonic J-pouch regarding the functional result have been substantiated the best [48, 49]. To prevent voiding problems, each limb of the pouch should not exceed 6cm in length [50]. In almost 75% of cases it is technically feasible to construct a colonic J-pouch [49]. In terms of functionality, the side-to-end anastomosis is probably equal to the colonic J-pouch [51], while transverse coloplasty is inferior to the latter [52].

Ostomy construction

In radical surgery of rectal cancer with TME and coloanal anastomosis, temporary diversion should be constructed. This can reduce morbidity (anastomotic failure, urgent repeat laparotomy) [53]. Colostomy and ileostomy are regarded as equivalent, but current meta-analyses favor the ileostomy [54, 55]. The stoma site should be marked before surgery. While the ileal stoma should be protruding (> 1cm), the colonic stoma is constructed with only slight elevation.

Local surgical procedures for rectal cancer

Local tumor excision (full-thickness excision) as the sole measure with curative intent (R0 resection) is ontologically adequate in pT1 carcinomas under the following conditions [56 - 59]:

• Maximum tumor diameter 3cm
• Well or moderately differentiated
• No invasion of the lymphatics (low-risk histology)

In comparison to radical surgery, the risk of local recurrence even in low-risk cases is higher, while at the same time their morbidity and mortality are lower; therefore, these risks must be weighed [60, 61]. Studies suggest that the technique of transanal endoscopic microsurgery is superior to open transanal excision with retractors [62, 63].

Since in T1 high-risk cancer (G3/4 and/or lymphatic invasion) and in T2 cancer, the incidence of lymph node metastasis is 10%–20%, local excision alone is not recommended [64, 65].

Laparoscopic surgery

With the appropriate expertise of the surgeon and suitable selection, laparoscopic resection of colorectal cancer can be performed with the same oncologic results as in open surgery. In the short term, the perioperative morbidity of minimally invasive procedures is lower, while total morbidity and mortality remain unchanged [66]. In the long-term course, no differences between laparoscopic and conventional surgery were found regarding the rate of incisional hernia, adhesion-related revision surgery and tumor recurrence [67, 68]. The British CLASSIC study also proved the oncologic safety of laparoscopic surgery in colorectal cancer [69, 70].

Transanal Versus Laparoscopic Total Mesorectal Excision For Mid And Low Rectal Cancer (TaLaR): A Multicentre Randomised Clinical Trial

Intraoperative Neuromonitoring of Pelvic Autonomous Nerve Plexus During Total Mesorectal Excision

A Prospective, Multicenter, Randomized, Open, Parallel Controlled, Non-inferiority Clinical Trial of Salvage Chemoradiotherapy Versus Radical Total Mesorectal Excision in the Treatment of Intermediate-risk Early Middle-low Rectal Cancer After Local Resection

Total Mesorectal Excision(TME) With Lateral Lymph Node Dissection Versus TME After Neoadjuvant Chemo-radiotherapy of Lower Rectal Cancer With Suspected Local Lymph Node Metastasis

1. Fielding, L.P., et al., Clinicopathological staging for colorectal cancer: an International Documentation System (IDS) and an International Comprehensive Anatomical Terminology (ICAT). J Gastroenterol Hepatol, 1991. 6(4): p. 325-44.

2. Soreide, O., et al., International standardization and documentation of the treatment of rectal cancer., in Rectal cancer surgery. Optimisation - standardization - documentation., O. Soreide and J. Norstein, Editors. 1997, Springer: Berlin Heidelberg New York. p. 405-45.

3. UICC, TNM Classification of Malignant Tumours. 6th Edition ed, ed. L.H. Sobin and C. Wittekind. 2002, New York: John Wiley & Sons.

4. Pilipshen, S.J., et al., Patterns of pelvic recurrence following definitive resections of rectal cancer. Cancer, 1984. 53(6): p. 1354-62.

5. Wittekind (Hrsg) (2017) TNM Klassifikation maligner Tumore. 8. Aufl. Wiley-VCH, Weinheim

6. MacDermid, E., et al., Improving patient survival with the colorectal cancer multi-disciplinary team. Colorectal Dis, 2009. 11(3): p. 291-5.

7. Burton, S., et al., MRI directed multidisciplinary team preoperative treatment strategy: the way to eliminate positive circumferential margins? Br J Cancer, 2006. 94(3): p. 351-7.

8. Segelman, J., et al., Differences in multidisciplinary team assessment and treatment between patients with stage IV colon and rectal cancer. Colorectal Dis, 2009. 11(7): p. 768-74.

9. Barillari, P., et al., Effect of preoperative colonoscopy on the incidence of synchronous and metachronous neoplasms. Acta Chir Scand, 1990. 156(2): p. 163-6. 646.

10. Faivre, J., [Endoscopic monitoring after excision of colorectal cancer]. J Chir (Paris), 1997. 134(7-8): p. 283-5. 647.

11. Chen, H.S. and S.M. Sheen-Chen, Synchronous and "early" metachronous colorectal adenocarcinoma: analysis of prognosis and current trends. Dis Colon Rectum, 2000. 43(8): p. 1093-9.

12. Neri, E., et al., Colorectal cancer: role of CT colonography in preoperative evaluation after incomplete colonoscopy. Radiology, 2002. 223(3): p. 615-9.

13. Floriani, I., et al., Performance of imaging modalities in diagnosis of liver metastases from colorectal cancer: a systematic review and meta-analysis. J Magn Reson Imaging, 2010. 31(1): p. 19-31.

14. Niekel, M.C., S. Bipat, and J. Stoker, Diagnostic imaging of colorectal liver metastases with CT, MR imaging, FDG PET, and/or FDG PET/CT: a meta-analysis of prospective studies including patients who have not previously undergone treatment. Radiology, 2010. 257(3): p. 674-84.

15. Levy, M., et al., Tumor markers in staging and prognosis of colorectal carcinoma. Neoplasma, 2008. 55(2): p. 138-42.

16. Lewis, M.R., et al., Metastatic colorectal adenocarcinoma involving the ovary with elevated serum CA125: a potential diagnostic pitfall. Gynecol Oncol, 2007. 105(2): p. 395-8.

17. Chen, C.C., et al., Is it reasonable to add preoperative serum level of CEA and CA19-9 to staging for colorectal cancer? J Surg Res, 2005. 124(2): p. 169-74.

18. Merkel, S., et al., The prognostic inhomogeneity in pT3 rectal carcinomas. Int J Colorectal Dis, 2001. 16(5): p. 298-304.

19. Nagtegaal, I.D. and P. Quirke, What is the role for the circumferential margin in the modern treatment of rectal cancer? J Clin Oncol, 2008. 26(2): p. 303-12.

20. Bipat, S., et al., Rectal cancer: local staging and assessment of lymph node involvement with endoluminal US, CT, and MR imaging--a meta-analysis. Radiology, 2004. 232(3): p. 773-83.

21. Puli, S.R., et al., Accuracy of endoscopic ultrasound to diagnose nodal invasion by rectal cancers: a meta-analysis and systematic review. Ann Surg Oncol, 2009. 16(5): p. 1255-65.

22. Purkayastha, S., et al., Magnetic resonance colonography vs computed tomography colonography for the diagnosis of colorectal cancer: an indirect comparison. Colorectal Dis, 2007. 9(2): p. 100-11.

23. Ahmetoglu, A., et al., MDCT with multiplanar reconstruction in the preoperative local staging of rectal tumor. Abdom Imaging, 2011. 36(1): p. 31-7.

24. Ahmetoglu, A., et al., MDCT with multiplanar reconstruction in the preoperative local staging of rectal tumor. Abdom Imaging, 2011. 36(1): p. 31-7.

25. Pezim, M.E. and R.J. Nicholls, Survival after high or low ligation of the inferior mesenteric artery during curative surgery for rectal cancer. Ann Surg, 1984. 200(6): p. 729-33.

26. Surtees, P., J.K. Ritchie, and R.K. Phillips, High versus low ligation of the inferior mesenteric artery in rectal cancer. Br J Surg, 1990. 77(6): p. 618-21

27. Slanetz, C.A., Jr. and R. Grimson, Effect of high and intermediate ligation on survival and recurrence rates following curative resection of colorectal cancer. Dis Colon Rectum, 1997. 40(10): p. 1205-18; discussion 1218-9.

28. Lange, M.M., et al., Level of arterial ligation in rectal cancer surgery: low tie preferred over high tie. A review. Dis Colon Rectum, 2008. 51(7): p. 1139-45.

29. Heald, R.J., E.M. Husband, and R.D. Ryall, The mesorectum in rectal cancer surgery--the clue to pelvic recurrence? Br J Surg, 1982. 69(10): p. 613-6.

30. Bokey, E.L., et al., Local recurrence after curative excision of the rectum for cancer without adjuvant therapy: role of total anatomical dissection. Br J Surg, 1999. 86(9): p. 1164-70.

31. Georgiou, P., et al., Extended lymphadenectomy versus conventional surgery for rectal cancer: a meta-analysis. Lancet Oncol, 2009. 10(11): p. 1053-62.

32. Gohl, J., W. Hohenberger, and S. Merkel, Lymph node dissection in rectal carcinoma: TME and what else? Onkologie, 2009. 32(1-2): p. 57-61.

33. Mortenson, M.M., et al., Total mesorectal excision and pelvic node dissection for rectal cancer: an appraisal. Surg Oncol Clin N Am, 2007. 16(1): p. 177-97.

34. Koch, M., et al., Is the lateral lymph node compartment relevant? Recent Results Cancer Res, 2005. 165: p. 40-5.

35. Scott, N., et al., Total mesorectal excision and local recurrence: a study of tumour spread in the mesorectum distal to rectal cancer. Br J Surg, 1995. 82(8): p. 1031-3.

36. Reynolds, J.V., et al., Pathological evidence in support of total mesorectal excision in the management of rectal cancer. Br J Surg, 1996. 83(8): p. 1112-5. 735.

37. Hida, J., et al., Lymph node metastases detected in the mesorectum distal to carcinoma of the rectum by the clearing method: justification of total mesorectal excision. J Am Coll Surg, 1997. 184(6): p. 584-8. 736.

38. Zaheer, S., et al., Surgical treatment of adenocarcinoma of the rectum. Ann Surg, 1998. 227(6): p. 800-11. 737.

39. Leong, A.F., Selective total mesorectal excision for rectal cancer. Dis Colon Rectum, 2000. 43(9): p. 1237-40.

40. Havenga, K., et al., Male and female sexual and urinary function after total mesorectal excision with autonomic nerve preservation for carcinoma of the rectum. J Am Coll Surg, 1996. 182(6): p. 495-502

41. Heald, R.J. and N.D. Karanjia, Results of radical surgery for rectal cancer. World J Surg, 1992. 16(5): p. 848-57.

42. Enker, W.E., Total mesorectal excision--the new golden standard of surgery for rectal cancer. Ann Med, 1997. 29(2): p. 127-33.

43. Bokey, E.L., et al., Local recurrence after curative excision of the rectum for cancer without adjuvant therapy: role of total anatomical dissection. Br J Surg, 1999. 86(9): p. 1164-70.

44. Lazorthes, F., et al., Distal intramural spread of carcinoma of the rectum correlated with lymph nodal involvement. Surg Gynecol Obstet, 1990. 170(1): p. 45-8. 741.

45. Kwok, S.P., et al., Prospective analysis of the distal margin of clearance in anterior resection for rectal carcinoma. Br J Surg, 1996. 83(7): p. 969-72. 742.

46. Andreola, S., et al., Distal intramural spread in adenocarcinoma of the lower third of the rectum treated with total rectal resection and coloanal anastomosis. Dis Colon Rectum, 1997. 40(1): p. 25-9. 743.

47. Goldstein, N.S., A. Soman, and J. Sacksner, Disparate surgical margin lengths of colorectal resection specimens between in vivo and in vitro measurements. The effects of surgical resection and formalin fixation on organ shrinkage. Am J Clin Pathol, 1999. 111(3): p. 349-51.

48. Brown, C.J., D.S. Fenech, and R.S. McLeod, Reconstructive techniques after rectal resection for rectal cancer. Cochrane Database Syst Rev, 2008(2): p. CD006040.

49. Fazio, V.W., et al., A randomized multicenter trial to compare long-term functional outcome, quality of life, and complications of surgical procedures for low rectal cancers. Ann Surg, 2007. 246(3): p. 481-8; discussion 488-90.

50. Hida, J., et al., Functional outcome after low anterior resection with low anastomosis for rectal cancer using the colonic J-pouch. Prospective randomized study for determination of optimum pouch size. Dis Colon Rectum, 1996. 39(9): p. 986-91.

51. Siddiqui, M.R., et al., A meta-analysis comparing side to end with colonic J-pouch formation after anterior resection for rectal cancer. Tech Coloproctol, 2010. 14(2): p. 113-23.

52. Liao, C., et al., Meta-analysis of the colon J-pouch vs transverse coloplasty pouch after anterior resection for rectal cancer. Colorectal Dis, 2010. 12(7): p. 624-31.

53. Montedori, A., et al., Covering ileo- or colostomy in anterior resection for rectal carcinoma. Cochrane Database Syst Rev, 2010(5): p. CD006878.

54. Klink, C.D., et al., [Protective ileostoma versus protective transverse stoma. What evidence is available?]. Chirurg, 2010. 81(11): p. 974-7.

55. Rondelli, F., et al., Loop ileostomy versus loop colostomy for fecal diversion after colorectal or coloanal anastomosis: a meta-analysis. Int J Colorectal Dis, 2009. 24(5): p. 479-88.

56. Hermanek, P. and G.P. Marzoli, Lokale Therapie des Rektumkarzinoms. Verfahren in kurativer Intention. 1994, Berlin Heidelberg Ney York Tokyo: Springer.

57. Winde, G., et al., Surgical cure for early rectal carcinomas (T1). Transanal endoscopic microsurgery vs. anterior resection. Dis Colon Rectum, 1996. 39(9): p. 969-76.

58. Sengupta, S. and J.J. Tjandra, Local excision of rectal cancer: what is the evidence? Dis Colon Rectum, 2001. 44(9): p. 1345-61. 767.

59. Matzel, K.E., S. Merkel, and W. Hohenberger, Lokale Therapieprinzipien beim Rektumkarzinom. Chirurg, 2003. 74(10): p. 897-904.

60. Ptok, H., et al., Oncological outcome of local vs radical resection of low-risk pT1 rectal cancer. Arch Surg, 2007. 142(7): p. 649-55; discussion 656.

61.  You, Y.N., et al., Is the increasing rate of local excision for stage I rectal cancer in the United States justified?:  a nationwide cohort study from the National Cancer Database. Ann Surg, 2007. 245(5): p. 726-33

62. Moore, J.S., et al., Transanal endoscopic microsurgery is more effective than traditional transanal excision for resection of rectal masses. Dis Colon Rectum, 2008. 51(7): p. 1026-30; discussion 1030-1.

63. Sgourakis, G., et al., Transanal endoscopic microsurgery for T1 and T2 rectal cancers: a metaanalysis and meta-regression analysis of outcomes. Am Surg, 2011. 77(6): p. 761-72.

64. Bach, S.P., et al., A predictive model for local recurrence after transanal endoscopic microsurgery for rectal cancer. Br J Surg, 2009. 96(3): p. 280-90

65. Hahnloser, D., et al., Immediate radical resection after local excision of rectal cancer: an oncologic compromise? Dis Colon Rectum, 2005. 48(3): p. 429-37.

66. Schwenk, W., et al., Short term benefits for laparoscopic colorectal resection. Cochrane Database Syst Rev, 2005(3): p. CD003145

67. Liang, Y., et al., Laparoscopic versus open colorectal resection for cancer: a meta-analysis of results of randomized controlled trials on recurrence. Eur J Surg Oncol, 2008. 34(11): p. 121724.

68.  Kuhry, E., et al., Long-term results of laparoscopic colorectal cancer resection. Cochrane Database Syst Rev, 2008(2): p. CD003432.

69. Guillou, P.J., et al., Short-term endpoints of conventional versus laparoscopic-assisted surgery in patients with colorectal cancer (MRC CLASICC trial): multicentre, randomised controlled trial. Lancet, 2005. 365(9472): p. 1718-26.

70. Jayne, D.G., et al., Five-year follow-up of the Medical Research Council CLASICC trial of laparoscopically assisted versus open surgery for colorectal cancer. Br J Surg, 2010. 97(11): p. 1638-45.