Colorectal

Question 1

Partial colectomy

Answer 1

1. Mobilize colon from retroperitoneal attachments in a medial to lateral approach, identifying [named arterial pedicle] first and proceeding to white line of toldt
2. Identify ureter and reflect laterally
3. Ligate vessels (Take at least 2 named vessels for formal resection) at the base of the mesentery, take lots of lymph nodes (need 12 or more to stage)
   → R Hemi: ilecolic, R colic watch for duo
   → Extended R Hemi: ileocolic, R colic, middle colic
   → L Hemi: L colic, proximal sigmoidal
   → Extended L Hemi: Middle colic, L colic, proximal sigmoidal
   → Transverse (try to avoid): Middle colic
   → Sigmoid colectomy: Superior rectal artery & L colic artery are
   divided at their origins, and the IMV is
   divided near the inferior edge of the pancreas

Question 2

Subtotal colectomy with ileorectal anastomosis

Answer 2

1. Lithotomy position
2. Transect TI with stapler, incise white line of Toldt
3. Continue dissection to mobilize hepatic flexure, protect duodenum
4. Enter lesser sac to mobilize splenic flexure
5. Continue mobilization of L colon, identify both ureters and retract laterally before taking mesentery of colon
6. Dissect distal to the rectosigmoid junction, excise surrounding mesorectum
7. Transect rectum , perform end to end EEA stapled ileorectal anastomosis
8. Completion proctoscopy with air leak test

Question 3

End colostomy

Answer 3

Excise 2cm circular piece of skin in LLQ

Make cruciate incision in anterior rectus sheath, Muscle split and incise peritonuem to accomodate 2 fingers

Exteriorize colon and excise the staple line

Full thickness bites to dermis with 3-0 vicryl, no brooke

Size and apply ostomy appliance

Question 4

Colostomy closure

Answer 4

Lower midline incision

Identify and dissect out the distal sigmoid stump

Take down the ostomy by incising 1mm of skin around stoma and separate from abdominal wall

Mobilize splenic flexure if necessary

Freshen edges by restapling
EEA stapler anastomosis: sew anvil in proximally, put stapler through anus

Question 5

Appendectomy

Answer 5

Infraumbilical Hassan, 5mm supraumbilical, 5mm LLQ

Free appendix from surrounding structures

Make mesoappendiceal window
take appendix with gold tri-stapler that is flush with the cecum

Take mesoappendix with gold tristapler”

Question 6

Low anterior resection (LAR)

Answer 6

1. Ex lap, mobilize the rectosigmoid colon beginning at sacral promontory. Develop plane between RP & colon mesentery.
2. Identify both ureters, identify IMA & perform high ligation of IMA & superior rectal artery.
3. Continue dissection along pericolic gutter up the descending colon and mobilize the splenic flexure
4. TME dissection posteriorly. Identify and preserve the hypogastric nerves.
5. Fully mobilize rectum, identify distal & proximal points of transection, ensuring 5 cm proximal & 2 cm distal (if low rectal cancer).
6. Perform tension free stapled EEA and leak test.
7. Create diverting loop ileostomy.

Question 7

Colorectal cancer staging

Answer 7

Neoadjuvant chemotherapy if Stage IV & resectable or potentially resectable

Surgical management
5 cm margins

Need at least 12 lymph nodes

Name vessels you will take

Question 8

APR

Answer 8

1. Preoperative stoma marking for end colostomy
2. Medial to lateral dissection of the rectosigmoid colon beginning at sacral promontory. Develop plane between RP & colon mesentery.
3. Identify both ureters, identify & perform high ligation of superior rectal artery.
4. Transect proximal margin at rectosigmoid junction.
5. TME dissection posteriorly. Identify and preserve the hypogastric nerves.
6. Fully mobilize rectum to pelvic floor, then transition to perineal dissection, staying mindful of tumor location and ensuring adequate margins.
7. Divide anococcygeal ligament until meeting up with abdominal dissection.
8. Create site of end sigmoid colostomy, mature after PRS closure.

Question 9

Lateral internal sphincterotomy (LIS)

Answer 9

1. Prone position, Use anoscopy to inspect anus & pathology
2. Identify intersphincteric groove
3. 2 cm radial incision along intersphincteric groove in right lateral position, away from hemorrhoidal tissue, extending from dentate line to just beyond the anal verge
4. Carry out the dissection to isolate internal sphincter muscle with kelly clamp
5. Divide the full thickness of the internal sphincter to the level of the dentate line
6. Close incision with interrupted 3-0 chromic suture

Question 10

Transabdominal rectal fixation (rectopexy)

Answer 10

For Low risk patient’s with rectal prolapse; If chronic constipation, add LAR or sigmoid resection

1. Lithotomy. Lower midline incision. Trendelendburg.
2. Retract sigmoid colon superiorly & to the left.
3. Mobilize sigmoid colon, preserving both ureters, gonadal vessels, presacral nerves, & superior hemorrhoidal artery, carry down to levator ani muscles.
4. Reduce redundancy of sigmoid colon by pulling cephalad until bowel is straight, but not taught, over sacral promontory.
5. Secure right lateral mesorectum to the sacrum using mattress 1 prolene suture x 3, ensuring rectal wall is not included.
6. Ensure hemostasis & close.

Question 11

Perineal rectosigmoidectomy (Altmeier Procedure)

Answer 11

Lithotomy

DRE

Prolapse rectum

Obtain exposure with self-retraining retractor

Inject lidocaine with epinephrine into rectal mucosa

Circumferential, full-thickness incision of rectum immediately above dentate line

Ligate & divide lateral rectal vessels within mesorectum & amputate prolapsed segment

Create coloanal anastomosis of proximal rectum/sigmoid colon to distal rectal stump, ensuring proper orientation & tension free, using absorbable sutures

Question 12

Hemorrhoidal banding

Answer 12

Prone jacknife

Enema

DRE & anascopy

1. Locate 3 hemorrhoidal bundles: right anterior, right posterior, left lateral
2. Ensure acting proximal to dentate line
   load the band on device, target vascular bundle just proximal the hemorrhoid and fire

Question 13

Hemorrhoidectomy

Answer 13

1. Prone jackknife, enema
2. Elevate submucosal space with local anesthetic
3. Incise perianal skin, minimizing anoderm excised
4. Dissect hemorrhoidal tissue off internal sphincter muscle.
5. Suture ligate hemorrhoidal pedicle with 3-0 Vicryl
6. Close mucosal defect with 3-0 chromic, leaving edge of wound open for drainage

Do not excise all 3 columns at once due to risk of anal stenosis

Question 14

Anorectal fistula management

Answer 14

Prone jacknife

DRE

Local anesthetic

Anoscopy

Identify external opening & internal opening using a probe abd/or hydrogen peroxide

Pass probe from external to internal opening, unroof fistula, identify any sidetracks; if >30% sphincter complex, place a seton by tying a vessel loop to probe, pulling through, and tying to itself

If intersphincteric & <30% IS involved, can perform fistulotomy (lowest risk of recurrence, but highest risk of incontinence)

Leave a drain/seton if multiple tracts

Question 15

Ligation of intersphincteric fistula tract (LIFT)

Answer 15

1. Prone jacknife, DRE, local, anoscopy
2. Exchange seton for fistula probe
3. Make an incision externally within the intersphincteric groove, dissect out fistula tract between external & internal sphincters so that only fistula probe is remaining.
4. Suture ligation of the internal and external openings.
5. Inject hydrogen peroxide before and after closing the external opening to confirm tract obliteration
6. Re-approximate mucosa

Question 16

Where do anorectal abscesses occur?

Answer 16

1. Intersphincteric
2. Ischiorectal - Lateral to rectal wall & space next to ischial tubercle
3. Perirectal/perianal
4. Supralevator
5. Submucosal
6. Deep postanal space - Bilaterally ends in ischiorectal fossa. Floor is anococcygeal ligament. Ceiling is levator muscle

Question 17

What are the types of fistula in ano?

Answer 17

Starts as cryptoglandular infection in the anal canal that leads to fistula tract in anorectal space; r/o Crohns w colonoscopy

1. Intersphincteric (most common)
2. Transsphincteric (high >1/3 complex vs low <1/3 complex)
3. Suprasphincteric (between muscles & up & over external sphincter)
4. Extrasphincteric (runs over & above sphincter complex)
5. Submucosal

Question 18

Modified hanley procedure

Answer 18

Use for horseshoe abscess/post anal space (Ischiorectal fossa; floor is anococcygeal ligament; ceiling is levator muscle)

1. Lithotomy, anoscopy examine anal canal
2. Drain postanal space by making skin incision at point of maximal fullness in posterior midline. Divide anococcygeal ligament.
3. Pass probe to identify internal opening to place a seton
4. Counter incisions overlying areas of maximal fullness in bilateral ischiorectal fossa. Pass probe to posterior midline to place setons bilaterally.
5. Use tonsil clamps to break up loculations and irrigate until effluent is clear

Question 19

Anorectal advancement flap

Answer 19

1. Lithotomy, anoscopy examine anal canal
2. Dissect a U shaped flap with mucosa, submucosa, & portion of internal sphincter distal to internal opening of fistula.
3. Extend flap proximally so that the length is 2x the base
4. Ligate internal opening
5. Advance mucosal flap 1 cm distal to internal fistula tract opening & suture flap to distal anal canal.

Question 20

Colonoscopy pearls
- How do you prep?
- Describe procedure
- Maneuvers to advance the scope & what to do if those dont work
- When do use bx forceps, snare polypectomy, EMR, ESMD
- When to place clips & tattoo following polypectomy

Answer 20

Prepare: Miralax split dose prep & CLD day before, NPO after midnight. Confirm no blood thinners & allergies.

1. Consent & timeout, LLD position
2. DRE, insert lubricated scope and pass scope under direct visualization all the way to cecum which is identified by visualizing appendiceal orifice, ileocecal valve, & crow’s foot of cecum
3. Slowly withdraw scope for at least 6 minutes

Maneuvers if unable to advance:
-Reduce loops in scope
-Manual pressure on abdomen by assistant
-Increased sedation
-Pediatric scope
-Placing on back
- If still unable, call senior partner
- If no luck, abort & perform virtual colonoscopy that day

Bx techniques
–Cold & hot bx forceps
–Cold & hot snare polypectomy → pedunculated polyps > 1 cm
–Endoscopic mucosal resection → sessile polyps > 1 cm
–Endoscopic submucosal dissection → >2 cm (dont do)

Close defect with clips if >1 cm

Tattoo all polyps greater than 1 cm; Describe location of tattoo in relation to mass

Question 21

Colonoscopy interval for
1. average risk patients
2. Pts with 1st degree relative with CRC or adenomas dx before age 60, or two 1st degree relatives dx at any age
3. One 1st degree relative diagnosed with colorectal CA after age 60, or two 2nd degree relatives
4. One 2nd degree relative with colorectal CA
5. FAP
6. HNPCC

Answer 21

1. Colonoscopy @ age 45 every 10 years or sigmoidoscopy every 5 years w/ annual FOBT
2. Colonoscopy @ age 40 (or 10 years prior to dx of youngest relative) every 5 years
3. Colonoscopy @ age 40 every 10 years
4. Screened as Average-risk
5. Sigmoidoscopy starting @ age 10-12 every year
6. Colonoscopy @ age 20-25 (or 10 years prior to dx of youngest relative) every 1-2 years

Question 22

Surveillance interval in personal history of adenomas
1. 1-2 tubular adenomas < 5 mm
2. ≥3 adenomas
3. Advanced adenomas (>1 cm, high grade, dysplasia, villous elements)
4. Hyperplastic polyps

Answer 22

1-2 tubular adenomas <5mm in size → 5 years

3 or more adenomas → 3 years

Advanced adenomas (>1cm, high grade, dysplasia or villous elements) → 3 years

Hyperplastic polyps → 10 years (considered to have normal exam)

Question 23

4 criteria to manage malignant polyp endoscopically

Answer 23

Polyp removed in one piece

Clear margins

Well to moderately differentiated without lymphovascular or perineural invasion

≤ 2 mm into muscularis mucosa (Haggitt’s class 1, 2, 3)

Question 24

Chemotherapy pearls for colon cancer

Answer 24

6 months FOLFOX - 5FU, (Leucovorin, Oxaloplatin) for Stage III and up (T3, T4, or N+), maybe high risk Stage II

KRAS wild-type → cetuximab (EGFR inhibitor)
Metastatic L → ertuximab
Metastatic R → avastin

Question 25

Follow up after colon cancer treatment

Answer 25

1. H&P & CEA q3m for 2 years, then q6m for total 5 years
2. CT chest/abdomen/pelvis q6m for 5 years
3. Colonoscopy @ 1 year, then 3 years, then no less frequently than q5 years

Question 26

Early rectal cancer: Indications for transanal excision & endoscopic polypectomy

Answer 26

For tumors T1 (submucosa) N0 M0

Criteria for transanal excision
1. Well to moderately differentiated & no lymphovascular or perineural invasion
2. <30% circumference
3. <3 cm in size
4. >3 mm clear margins
5. Within 8 cm of anal verge

Criteria to manage malignant polyp endoscopically
1. Polyp removed in one piece
2. Clear margins
3. Well to moderately differentiated without lymphovascular or perineural invasion
4. ≤ 2 mm into muscularis mucosa (Haggitt’s class 1, 2, 3)

Question 27

Early rectal cancer (limited to T1 & T2N0) not amenable to transanal/endoscopic treatment

Answer 27

Proctectomy with LAR vs APR. Need at least 1-2 cm margins

Measure distance of tumor from sphincter & anal verge

–Upper ⅓ rectum: 5 cm margins
–Lower ⅔ rectum: LAR with TME with 2 cm margins ideally, 1 cm may be ok; if can’t get this then need APR
–Very distal rectal cancers (extending into anal canal) or within 2 cm of anal verge → APR→ Worst rate of survival & recurrence

–Can offer neoadjuvant chemoradiation for tumors in the mid-distal rectum to avoid upstaging and avoid post-op radiation

Question 28

Locally advanced rectal cancer

Answer 28

TNT - Total Neoadjuvant Therapy - Induction chemotherapy + long-course chemoradiotherapy or induction chemotherapy with short-course radiotherapy

Followed by transabdominal excision (LAR vs APR)

Question 29

Anal SCC work up

Answer 29

HIV status, sexual orientation/activity, pap smears, smoking, HPV

Need anoscopy, inguinal LN exam

CT chest/abd/pelvis, pelvic MRI, colonoscopy

Question 30

Anal squamous intraepithelial neoplasm classification & treatment

Answer 30

HPV 6 & 11 → LSIL & condyloma accuminatum
HPV 16 & 18 → High grade/HSIL/CIS/Bowen’s & squamous cell carcinoma

LSIL: Not precursor
HSIL: Precursor

Discuss options for home/topical treatments (16 weeks) vs office procedure vs operating procedure

Home tx: 5FU, imiquimod

In office tx: Electrocautery ablation, 80% trichloroacetic acid (can be painful)

Operating room: HRA-directed surgical ablation or surgical excision (no more than 50% of ATZ circumference at one visit)

Question 31

Condyloma acuminata treatment

Answer 31

First-line patient-applied therapies include:
●Imiquimod
●Podophyllotoxin
●Sinecatechins

First-line clinician-administered therapies include:
●Cryotherapy
●Trichloroacetic acid (TCA) and bichloroacetic acid (BCA)
●Surgical removal (excision, electrosurgery, or laser)

Question 32

SCC of anal CANAL management & follow up

Answer 32

5-FU, mitomycin C, concurrent radiation (3000 cGy)
1. Re-evaluate with physical exam 8 weeks after completion
– Complete remission → Follow with physical exam q3-6 months for 5 years & imaging q1 year for 3 years
–Persistent disease → Bx & follow up q1 month for 6 months
–Progressive disease or persistent disease at 6 months → Restage patient & consider APR
–Recurrent→ salvage APR - need wide excision w PRS

Inguinal lymph nodes + on FNA, needs extra radiation to groin vs dissection

Question 33

SCC of anal MARGIN management

Answer 33

If any of the following present → 5FU & mitomycin based chemoradiation
1. Tumor not a discrete skin lesion that is separate from the anal canal; Question as to tumor epicenter in anus or perianal skin
2. Tumor size 2 cm or larger
3. Poorly or moderately differentiated histology
4. Sphincter function potentially compromised by
resection
5. Clinical evidence of nodal involvement

If none of the above present → WLE with 1 cm negative margins

Question 34

Anal fissure management

Answer 34

1. Determine hypertonic vs hypotonic anal sphincter (hypotonic = high risk of incontinence, consider anorectal manometry to confirm)
2. Location - most commonly anterior/posterior midline; if lateral, need to rule out HIV, corhn’s, cancer - bx & colonoscopy
3. Conservative tx for 4 weeks (80% heal)
   → Topical lidocaine, stool softeners, sitz baths, fiber, topical NG/nifedipine/diltiazem
4. If fails conservative tx, try debridement & botox injection to determine if LIS would work & see if incontinent
5. Surgical treatment
   –Low risk of incontinence → RIGHT lateral internal sphincterotomy (LIS)
   –High risk of incontinence → fissurectomy & V-Y anal advancement flap