TaTME Versus Open Intersphincteric Resection After Neoadjuvant Concurrent Chemoradiotherapy.
Condition: Rectal Cancer
MeSH terms: Rectal Neoplasms
Study type: Interventional

Summary: 
      The two surgical options for lower 1/3 rectal cancer is APR and sphincter sparing procedures.
      Intersphincteric resection is procedure to treat very low rectal cancer within 2 cm from the
      dentate line to avoid permanent colostomy,improves the quality of life with better
      genitourinary function. Neoadjuvant chemo-radiotherapy is routine for T3 cases.
    

Detailed description: 
      During the period between April 2013 and July 2019, a non-randomized controlled study was
      performed at two tertiary centers; Oncology Centre of Mansoura University and Policlinico
      Umberto Primo surgery department of SAPIENZA university of Rome after referral from the
      clinical oncology and nuclear medicine department. After diagnosis of ultralow rectal cancer,
      a written informed consent was obtained from patients after full explanation of the
      procedure, the likely outcome and the potential complications that may occur. Digital rectal
      examination was conducted to assess the distance of lower tumor margin from the anal verge
      and the anal tone. Anesthetic fitness and tumour markers (CEA) were assessed. Pelvis MRI
      and/or endorectal ultrasound (EUS), abdomen and chest CT scan and colonoscopy with biopsy
      were done for all cases. Re-evaluation after neoadjuvant chemo-radiotherapy by MRI and EUS.
      Inclusion criteria included a very low rectal cancer below 5 cm from the anal verge with
      normally continent and tumor-free external anal sphincter. Neoadjuvant treatment was given to
      all patients with T3 or node positive tumors. Exclusion criteria were T4, metastatic tumors
      and fecal incontinence. Fifty patients were excluded from the study (Fig.1). One hundred and
      ten patients with ultralow rectal adenocarcinoma, with matched age and sex (table 1), were
      non-randomly classified into two equal groups: the control group included 55 patents that
      underwent sphincter sparing by open ISR with TME (O-ISR Group) and the 2nd group included 55
      patents that underwent Transanal minimally invasive ISR with TME (TAMIS Group).

      Surgical technique:

      In open ISR, the inferior mesenteric vessels were highly ligated. After full mobilization of
      the left colon and splenic flexure was done, the plane for TME was followed down in the
      pelvis superficial to the hypogastric fascia as low as possible to enter into the posterior
      intersphincteric plane. A non-endoscopic perineal phase was then initiated using an anal
      lone-star retractor to expose the anal canal. Both the mucosa and the muscular layer were
      incised 1cm below the tumor margin to transect the internal anal sphincter (IAS) and then
      closed by purse string sutures. The dissection continued between IAS and the external anal
      sphincter (EAS) starting posteriorly then laterally, where EAS is easier to identify, then
      anteriorly where the plane presented more adhesions with the urethra in male or vagina in
      female till reaching the abdominal dissection. Proximal division of the specimen started just
      below the site of inferior mesenteric vessels ligation and continued till division of the
      marginal artery at the site of the required anastomosis. The Specimen extraction and division
      was done extra-anal. A defunctioning ileostomy was done in all cases.

      In TAMIS-TME, using a lone star retractor, the 1st step was to divide and close the anal
      canal by purse-string suturing to enter the intersphincteric plane. Using TEo platform (Karl
      Storz, Tuttilingen, Germany) (fig. 2) with a 4 cm size operating proctoscope diameter,
      Transanal endoscopic dissection was initiated and continued in the intersphincteric plane
      starting posteriorly then laterally. Partial or high ISR started at the dentate line to
      remove the upper half of IAS for ultralow tumors at 3 to 4.5 from anal verge. Total or low
      ISR started 1 cm below the dentate line, removing the whole of IAS for tumours below 3 cm
      from the anal verge. The endoscopic dissection continued in the same sequence as the control
      group along the levator ani. Then continue posteriorly till reaching as much as possible,
      then dissection continued laterally and anteriorly to reach the peritoneal reflection. Then,
      the laparoscopic phase was initiated to ligate the inferior mesenteric vessels and mobilize
      the splenic flexure and left colon. The peritoneal reflections were then divided to connect
      to the transanal part. The specimen was then extracted transanally and the Colo-anal
      anastomosis was done in two layers. A defunctioning ileostomy was done in all cases.
    

Intervention name(s): Open intersphincteric resection; transanal minimally invasive intersphincteric resection
Intervention type(s): Procedure; Device
Intervention description(s): laparotomy arm: surgical Instruments for open approach operation: Abdominal anterior resection combined with peranal intersphincteric resection of the rectum
Abdominal step a high ligation of the inferior mesenteric artery is performed together with a full mobilization of the left colon. A circular incision of the anal canal is performed 1 cm below the tumour. Both the mucosa and the muscular layer are incised to transect the internal anal sphincter. A coloanal anastomosis, transverse coloplasty or colonic J-pouch and a diverting loop ileostomy are associated with the hand-sewn coloanal anastomosis.
laparoscopic approach group: instruments used: laparoscopic instruments mentioned at the arm description
intervention: laparoscopic mobilization of the rectum and colon combined with the peranal intersphincteric resection as in the laparotomy approach; minimally invasive approach group: instruments used: laparoscopic instruments mentioned at the arm description instruments: laparoscopic instruments mentioned in the laparoscopic rectal resection arm intervention: laparoscopic mobilization of the rectum and colon combined with the peranal intersphincteric resection as in the laparotomy approach
Other intervention name(s): sphincter preserving procedures in low rectal cancer; very low rectal cancer resection; interspincteric resection; laparoscopic low anterior resection combined with trans-anal endoscopic intersphincteric resection; lTAMIS
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: sphincter sparing procedures; intersphincteric resection; rectal cancer; ultralow rectal cancer; sphincter preserving procedures; Abdominoperineal resection; Trans-anal minimally invasive surgery; TAMIS versus open colorectal resection; neoadjuvant chemo-radiotherapy for rectal cancer