Transanal Resection of Rectal Tumors  
Megan Shroder and Alexander Hawkins 
 
OPEN MANUAL OF SURGERY IN RESOURCE-LIMITED SETTINGS 
www.vumc.org/global-surgical-atlas 
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License  
 
Editor’s Note: It is rare in our setting for patients 
with malignant rectal tumors to present at an early 
stage, where the tumor can be removed by transanal 
resection. The principles of surgical planning, 
exposure, and resection in this chapter will be useful 
for such operations, and for others that require 
surgical intervention in the distal rectum. -RD 
 
Introduction:  
Management 
of 
rectal 
tumors 
differs 
depending on size of the tumor, location within the 
rectum, and stage of disease. For early stage (T1 or 
Tis) rectal tumors without high-risk features, or 
rectal polyps unable to be removed endoscopically, 
local transanal excision is the preferred surgical 
approach.  
 
Rectal adenocarcinomas amenable to local 
transanal excision include those that are stage T1 (or 
Tis) without clinical or radiologic evidence of nodal 
involvement, < 3 cm in diameter, encompass < 40% 
of the circumference of the rectum, are mobile on 
examination, lack perineural or lymphovascular 
invasion, and are well-differentiated. For T1 tumors, 
overall and local recurrence at 5 years remains 
slightly higher than following a total mesorectal 
excision, but this risk increases significantly with 
lesions > 3 cm or > T1 stage.  
 
Tumors or lesions within the middle to distal 
rectum are often accessible via a transanal approach, 
though more proximal lesions may require a formal 
resection, such as a low anterior resection of the 
rectum. Transanal excision is not recommended 
above the peritoneal reflection as a full thickness 
excision may result in entry into the peritoneal cavity. 
 
Much of the success of local resection is 
dependent on patient positioning and instrument 
selection. Most lesions (lateral and anterior) are 
accessible via prone-jackknife patient positioning, 
but lithotomy positioning should be utilized in the 
case of a posterior lesion.  
 
We utilize a Lone Star® ring retractor to 
provide effacement of the anal canal and assist with 
bringing the lesion closer to the anal verge (Lone 
Star® 
is 
a 
product 
of 
Cooper 
Surgical). 
Circumferential anal retraction sutures can also be 
utilized as an alternative if this retractor if it is not 
available. These are thick sutures placed in 4-8 
locations around the anal canal to pull the anal 
mucosa to the perianal skin. They are removed at 
completion of the case. 
 
  
 
Retractors like the Lone Star® utilize placement of sharp 
hooks/stays 1-2 cm into the anal canal and threading them 
through the retractor system at the desired tension. This is 
completed circumferentially around the anal canal until 
appropriate retraction is obtained. Sutures between the anal 
canal and the skin are an option where this device is not 
available.  
 
In addition to anal circumferential retraction, 
visualization and retraction within the canal can be 
accomplished utilizing many different anorectal 
retractors/speculums. Examples of these include 
Roschke 
retractors, 
Anoscopes, 
Hill-Ferguson 
retractors, 
Bodenhammer 
speculums, 
Sawyer 
retractors, Pratt rectal speculums, and more. Some of 
these instruments will be more helpful in visualizing 
some lesions over others. For example, Hill-
Ferguson retractors can easily show a distal lesion, 
while anoscopes may be more helpful for more 
proximal rectal lesions.  
 
Transanal Resection of Rectal Tumors  
Megan Shroder and Alexander Hawkins 
 
OPEN MANUAL OF SURGERY IN RESOURCE-LIMITED SETTINGS 
www.vumc.org/global-surgical-atlas 
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License  
 
 
Hill-Ferguson 
retractors 
such 
as 
this 
one 
provide 
circumferential retraction and allow focused attention on a 
lesion in the distal rectum.  
 
Local resection of a rectal tumor proceeds in the 
following steps:  
• Induction of general or monitored anesthesia (+/- 
intubation) 
• Patient positioning 
• Digital Rectal Examination (DRE) 
• Placement of anal retractors 
• Visualization of mass  
• Resection of mass 
• Orientation of the mass for pathology review 
• Repair of defect 
 
Steps: 
1. Ensure preparation of  instruments, including 
retractors and a headlight if possible. Ideally, 
patients should undergo an enema for bowel 
preparation prior to the operation. 
2. Determine ideal patient positioning and discuss 
with anesthesiology prior to moving the patient 
onto the operating room table to optimize your 
set-up. If the lesion is in the posterior rectum, it 
will be best visualized in lithotomy position. 
Lesions in the anterior rectum will be better 
visualized in the prone-jackknife position. Keep 
in mind that anesthesia is more difficult and 
dangerous in the prone position, so consider 
whether your anesthesia team’s capacity when 
making this decision. See Approach for 
Positioning the Patient and the Surgeon. 
3. For prone-jackknife positioning (anterior or 
lateral masses), place padding or support at the 
patient’s head, upper chest, across their pelvis at 
the level of the anterior superior iliac spines, 
knees, and shins. For cases requiring general 
anesthesia, the patient is often intubated on their 
stretcher and is then flipped by the operating 
room team into a prone position after induction 
of anesthesia. See Prone Position. 
 
The prone jackknife position is best suited for tumors located 
in the anterior rectum: a surgeon standing next to the patient 
is looking down on the tumor. By Saltanat ebli - Own work, 
CC0, 
https://commons.wikimedia.org/w/index.php?curid=25388640 
 
4. For lithotomy positioning (posterior masses), the 
patient can be transferred to the operating room 
table in standard fashion. After induction of 
anesthesia, they must be moved down on the 
operating table so their anal verge is located just 
above the end of the bed. Their legs should be 
placed in stirrups and the end of the bed should 
be removed/folded away for adequate exposure.  
Transanal Resection of Rectal Tumors  
Megan Shroder and Alexander Hawkins 
 
OPEN MANUAL OF SURGERY IN RESOURCE-LIMITED SETTINGS 
www.vumc.org/global-surgical-atlas 
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License  
 
 
The lithotomy position is best suited for tumors in the posterior 
rectum: a surgeon sitting of standing between the patient’s legs 
is looking down on the tumor. By Saltanat ebli - Own work, CC 
BY-SA 3.0, 
https://commons.wikimedia.org/w/index.php?curid=23397027  
 
5. After positioning of the patient and induction of 
anesthesia, the patient should be adequately 
secured to the table with straps in multiple 
locations (legs, chest).  
6. Raise the table to an appropriate height for 
standing or sitting on a stool if patient is in 
lithotomy position. Prepare the perianal region 
with a sterile skin preparation solution and drape 
the patient.  
7. Perform a digital rectal examination and 
anoscopy as indicated.  
8. Place a Lone Star® retractor around the anal 
canal and secure the tightening dials to allow it to 
lay flush against the perineum. Stays/hooks 
should be placed in multiple positions (at least 8) 
around the anal canal. Be careful to avoid causing 
a sharp injury to the surgical team during 
placement of the Lone Star® hooks.  
 
Lone Star® retractor placement with stays/hooks placed 
circumferentially around the anal canal and secured to the 
device with appropriate tension to aid in visualization without 
causing tearing/injury. A creative surgeon with a self-retaining 
retractor system that attaches to the patient’s bed could 
duplicate this exposure by placing sutures through the mucosa 
in the anal canal and attaching them to the retractor.  
 
9. Utilize a retractor (rectal speculum shown below) 
to visualize the lesion/mass. Tip: a traction suture 
can be placed just proximal to the lesion to apply 
pressure and pull it closer to the anus if there is 
difficulty visualizing. Additionally, utilizing an 
atraumatic grasper/clamp on the lesion may also 
be helpful at this step.  
10. With electrocautery (bipolar or monopolar), 
score or mark 1 cm margins around the lesion.  
11. Incise the rectal mucosa and extend the incision 
laterally and proximally with 1 cm margins 
circumferentially. The incision should extend to 
the perirectal fat with caution to avoid injury to 
adjacent structures, especially anteriorly (such as 
the prostate gland or vagina).  
 
 
Transanal Resection of Rectal Tumors  
Megan Shroder and Alexander Hawkins 
 
OPEN MANUAL OF SURGERY IN RESOURCE-LIMITED SETTINGS 
www.vumc.org/global-surgical-atlas 
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License  
 
 
Rectal speculum and Lone Star® retractor aide in visualization 
of the rectal mass, which is grasped with an atraumatic 
instrument. Photo courtesy of Dr. Timothy Geiger 
 
12. After excision of the mass, it should be oriented 
for 
pathology. 
Markings 
should 
indicate 
laterality, superficial vs. deep, and proximal vs. 
distal.  
 
                    
 
Marking of the specimen for pathology examination. Sutures of 
different lengths will now be placed on the specimen and 
communicated to the pathologist in the request form. Photo 
courtesy of Dr. Timothy Geiger. 
 
 
 
13. The defect should be closed in a single, full-
thickness layer. This is done in a transverse 
manner with absorbable suture (i.e. Vicryl). This 
can be done in an interrupted or running fashion. 
14. The anal canal should be inspected for defects or 
bleeding. Hemostasis should be obtained with 
electrocautery or additional sutures as indicated.  
 
Pitfalls 
• Appropriate padding and support of patients in 
the prone-jackknife and lithotomy positions is 
crucial. Pressure injuries to the genitals, 
shoulders, and lower extremities can occur 
quickly and should be prevented starting with 
preparation of the table set-up even before the 
patient enters the operating room.  
• Anterior lesions put patients at higher risk of 
iatrogenic injury to the prostate gland, vagina, 
and other parts of the genitourinary tract. Take 
care to avoid injury to these structures.  
• Complications are rare from local transanal 
excision, but post-operative understanding of the 
presentation 
and 
management 
of 
hemorrhage/bleeding, infection or pelvic sepsis, 
rectovaginal fistulae, perforation, and urinary 
retention is crucial.  
• If the lesion is difficult to visualize during 
removal, tension sutures can be placed around the 
margin of excision while the mass is being 
excised. This helps to ensure appropriate 
visualization when the defect is being closed.  
 
Megan Shroder, MD MPH 
Alexander Hawkins, MD MPH 
Vanderbilt University Medical Center 
Nashville, Tennessee USA 
 
October 2024 
