Nazem Shams, Malak Shawki Mansoura University Oncology Centre (OCMU)
The optimal operation for rectal cancer still remains controversial, a new concept of total mesorectal excision (TME) was introduced, and its feasibility and efficacy had been confirmed by a series of clinical trials (Zong et al., 2003). Total mesorectal excision with pelvic autonomic nerve preservation has been reported to be an optimal surgery for rectal cancer. It minimizes local recurrence and sexual and urinary dysfunction (Kim et al.,2005).
The aim of this research is to study the value of total mesorectal excision versus subtotal mesorectal excision in management of cancer rectum to reduce rate of local recurrence and pelvic nerve preservation to avoid postoperative urinary and sexual dysfunction.
Technique of TME Patient demographic data CharacteristicsNumber Total no. of patients (n) % Age (mean) (years) 44.6%- Gender Male Female % 42.7% After mobilizing the sigmoid colon from its attachments to the lateral abdominal wall, the peritoneum around the pouch of Douglas is incised. Meticulous, precise and sharp dissection (scissors or electrocautry) under direct vision of exposed loose areolar tissues and small vessels between the visceral and parietal fascia allows a specimen oriented operation with an intact bilobed mesorectum avoiding any tearing or disruption. The branches of superior hypogastric nerves lie behind the mesorectum and represent kind of a guide to its excision. The mesorectum is pulled forward so as to leave the nerves behind. Then, dissection moves caudal down to the plane of levators. TME continues anteriorly where the inferior hypogastric or pelvic plexus is commonly located between rectum and bladder in men, more lateral in women. When dissection is performed in the lateral ligaments there is no fascia protecting nerves, hence in this region, coagulation is avoided also in respect to the middle rectal artery. TME consists of radical clearance of the posterior, distal and lateral mesorectum TME starts posteriorly by dissection through Heald’s plane ( Holy plane ) between Waldayer’s fascia and rectal fascia In men, the Denonvillier’s fascia at the prostatic level protects the nervi erigentes coming from the pelvic plexus ( Branches S2, S3 and S4 ). So, dissection at this level is conducted behind this fascia, removing only the part of mesorectum above the prostate, attached to the rectal wall in the median position. The fourth pelvic parasympathetic nerve(S4), which travel close to the inferior vesical vein is essential for the sensation and voiding function of the bladder and therefore, selective preservation of this nerve proves beneficial in preserving urinary function. TME must be differentiated from the so called subtotal mesorectal excision which need only to remove the mesorectum to the level 5 cm below the lower edge of the tumor rather than anatomical mesorectum or incomplete lateral dissection. Between March 1997 and March 2007,TME was performed in 150 patients: They included 86 males and 64 females. with a median age Patients with advanced rectal tumors were excluded from the study. Urodynamic examination: All patients were subjected to urodynamic examination. The duration between the operation and urodynamic examination varied from 6 months to 1 year with a mean duration of 9 months. A uroflowmeter automatically measures the amount of urine and the flow rate. The patients were asked to urinate privately into a toilet that contains a collection device and scale. Tumor characteristics Distance of tumor from anal verge, cm < > % 44% 34.7% Dukes stage (n A B C D % 37.33% 33.33% 2.66% Positive lymph nodes 5436% Group No. % Operation L A R A P R Operative intervention
Recurrence Follow up of the patients was on all patients with a mean follow-up of 93 months (range, 6 – 120) revealed; Isolated local pelvic recurrence was found in 8 patients (5.3% ).the mean time to local recurrence was 14 months (range,6-24).
Oncological treatment failure Stage and No of patients Local recurrence Distant metastases Anastmotic recurrence Pelvic recurrence Duke ’ s A 003 Duke ’ s B 225 Duke ’ s C 1312
5-year overall survival
Mean maximal urinary flow rate in ml/sec for patients included in that study %No. of patients Mean max. flow rate Less than More than 20
%No. of patientsVoided volume Less than More than 500 Voided volume in ml for patients included in the study
No patients revealed residual urine nor neurogenic bladder requiring catheterization.
Normal Flowmetry (Q max=28.9 ml/sec) for a female patient subjected to total mesorectal excision and pelvic nerve preservation.
Another normal Flowmetry (Q max=10.4 ml/sec) for a female patient subjected to total mesorectal excision and pelvic nerve preservation.
Abnormal Flowmetry (Q max=6 ml/sec) for a male patient subjected to subtotal mesorectal excision and conventional method.
Sexual function U.S color Doppler Study revealed normal biphasic arterial and venous pulsations on both sides in 69 patients (80%) and abnormal in only 17 patient (20%). U.S color Doppler Study revealed normal biphasic arterial and venous pulsations on both sides in 69 patients (80%) and abnormal in only 17 patient (20%).
U.S color Doppler study for patients included in that study
Local Study Dates Recurrence Rate (%) No. of patients Authors Heald Dixon Enker Aitken Maas Havenga Martling Bissett Kapiteijin – Wibe 2002 Our study Local recurrence rate after TME (oncologic outcome) as a comparable study
Urinary and male sexual function after conventional rectal cancer surgery Lack of ejaculation % Loss of erection % Bladder dysfunction % No. of patients YearAuthor n.a Kinn Cunsolo Hojo 3053n.a Koukouras
Urinary and male Sexual function after introduction of TME as a comparable study Lack of ejaculation % Loss of erection % Bladder dysfunction % No. of patients YearAuthor Enker n.a Leveckis Havenga Maas Nesbakken Nagawa Maurer Pocard Kim Our study
Serious problems in the surgical treatment of patients with rectal carcinoma are local failure, urinary and sexual dysfunction. To resolve these problems, pelvic autonomic nerve preservation combined with total mesorectal excision has been introduced.
So, we conclude that the introduction of total mesorectal excision (TME) with pelvic nerve preservation (ANP) is one of the largest improvements in the outcome of rectal cancer. We recommended TME –ANP to improve not only prognosis in terms of local recurrence, but also in terms of overall survival and preserving urinary and sexual activities.