Surgical Recall: 49 - Anus

Front 1

What is structure 1?

Back 1

Anal columns

Front 2

What is structure 2?

Back 2

Dentate line

Front 3

What is structure 3?

Back 3

Rectum

Front 4

What is structure 4?

Back 4

External sphincter

Front 5

What is structure 5?

Back 5

Internal sphincter

Front 6

What is structure 6?

Back 6

Levator ani muscle

Front 7

What is the most common carcinoma of the anus?

Back 7

Squamous cell carcinoma (80%)

Front 8

What cell types are found in carcinomas of the anus?

Back 8

1. Squamous cell carcinoma (80%)

2. Cloacogenic (transitional cell)

3. Adenocarcinoma / melanoma / mucoepiermal

Front 9

What is the incidence of anal carcinoma?

Back 9

Rare (1% of colon cancer incidence)

Front 10

What is anal Bowen's disease?

Back 10

Squamous cell carcinoma in situ

Front 11

How is Bowen's disease of the anus treated?

Back 11

With local wide excision

Front 12

What is Paget's disease of the anus?

Back 12

Adenocarcinoma in situ of anus

Front 13

How is Paget's disease of anus treated?

Back 13

With local wide excision

Front 14

What are the risk factors for anal cancer?

Back 14

- HPV

- Condyloma

- Herpes

- HIV

- Chronic inflammation (fistulae, Crohn's)

- Immunosuppression

- Homosexuality in males

- Cervical / vaginal cancer

- STDs

- Smoking

Front 15

What is the most common symptom of anal carcinoma?

Back 15

Anal bleeding

Front 16

What are the other signs/symptoms of anal carcinoma?

Back 16

Pain, mass, mucus per rectum, pruritus

Front 17

What percentage of patients with anal cancer is asymptomatic?

Back 17

~25%

Front 18

To what locations do anal canal cancers metastasize?

Back 18

Lymph nodes, liver, bone, lung

Front 19

What is the lymphatic drainage below/above the dentate line?

Back 19

Below to inguinal lymph nodes (above to pelvic chains)

Front 20

Are most patients with anal cancer diagnosed early or late?

Back 20

Late (diagnosis is often missed)

Front 21

What is the workup of a patient with suspected anal carcinoma?

Back 21

- History

- PE: digital rectal exam, proctoscopic exam, colonoscopy

- Biopsy of mass

- Abdominal/pelvic CT scan, transanal U/S

- CXR

- LFTs

Front 22

What is a "margin cancer"?

Back 22

Anal verge out 5 cm onto perianal skin

Front 23

What is "canal cancer"

Back 23

Proximal to anal verge up to border of internal sphincter

Front 24

How is an anal canal epidermal carcinoma treated?

Back 24

NIGRO protocol:

1. Chemotherapy (5-FU and mitomycin C)

2. Radiation

3. Post-radiation therapy scar biopsy (6-8 weeks post XRT)

Front 25

What percentage of patients have a complete response with the NIGRO protocol?

Back 25

90%

Front 26

What is the 5-year survival with the NIGRO protocol?

Back 26

85%

Front 27

What is the treatment for local recurrence of anal cancer after the NIGRO protocol?

Back 27

May repeat chemo / XRT or salvage APR

Front 28

How is a small (<5 cm) anal margin cancer treated?

Back 28

Surgical excision with 1-cm margins

Front 29

How is a large (>5 cm) anal margin cancer treated?

Back 29

Chemoradiation

Front 30

What is the treatment of anal melanoma?

Back 30

Wide excision or APR (especially if tumor is large) +/- XRT, chemo, post-op

Front 31

What is the 5-year survival rate with anal melanoma?

Back 31

<10%

Front 32

How many patients with anal melanoma have an amelanotic anal tumor?

Back 32

Approximately 1/3, thus making diagnosis difficult without pathology

Front 33

What is the prognosis of anal melanoma?

Back 33

<5% 5-year survival rate

Front 34

What is fistula in ano?

Back 34

Anal fistula, from rectum to perianal skin

Front 35

What are the causes of fistula in ano?

Back 35

Usually anal crypt/gland infection (usually perianal abscess)

Front 36

What are the signs/symptoms of fistula in ano?

Back 36

- Perianal drainage

- Perirectal abscess

- Recurrent perirectal abscess

- Diaper rash

- Itching

Front 37

What disease should be considered with fistula in ano?

Back 37

Crohn's disease

Front 38

How is the diagnosis of fistula in ano made?

Back 38

Exam, proctoscope

Front 39

What is Goodsall's rule?

Back 39

- Fistulas originating anterior to a transverse line through the anus will course STRAIGHT ahead and exit anteriorly

- Fistulas exiting posteriorly have a CURVED tract

Front 40

How can Goodsall's rule be remembered?

Back 40

Think of a dog with a STRAIGHT nose (anterior) and a curved tail (posterior)

Front 41

What is the management of anorectal fistulas?

Back 41

1. Define the anatomy

2. Marsupialization of fistula tract (ie, fillet tract open)

3. Wound care: routine Sitz baths and dressing changes

4. Seton placement if fistula is through the sphincter muscle

Front 42

What is a seton?

Back 42

Thick suture placed through fistula tract to allow slow transection of sphincter muscle; scar tissue formed will hold the sphincter muscle in place and allow for continence after transection

Front 43

What percentage of patients with a perirectal abscess develop a fistula in ano after drainage?

Back 43

~50%

Front 44

How do you find the internal rectal opening of an anorectal fistula in the OR?

Back 44

Inject H2O2 (or methylene blue) in external opening - then look for bubbles (or blue dye) coming out of the internal opening!

Front 45

What is a sitz bath?

Back 45

Sitting in a warm bath (usually done after bowel movement and TID)

Front 46

What is a perirectal abscess?

Back 46

Abscess formation around the anus / rectum

Front 47

What are the signs/symptoms of perirectal abscess?

Back 47

- Rectal pain

- Drainage of pus

- Fever

- Perianal mass

Front 48

How do you diagnose perirectal abscess?

Back 48

Physical / digital exam reveals a perianal / rectal submucosal mass / fluctuance

Front 49

What is the cause of perirectal abscesses?

Back 49

Crypt abscess in dentate line with spread

Front 50

What is the treatment of perirectal abscesses?

Back 50

As with all abscesses (except simple liver amebic abscess) DRAINAGE, sitz baths, anal hygiene, stool softeners

Front 51

What is the indication for post-op IV antibiotics for drainage with perirectal abscess?

Back 51

- Cellulitis

- Immunosuppression

- Diabetes

- Heart valve abnormality

Front 52

What percentage of patients develop a fistula in ano during the 6 months after surgery for perirectal abscess?

Back 52

~50%

Front 53

What is an anal fissure?

Back 53

Tear or fissure in the anal epithelium

Front 54

What is the most common site for an anal fissure?

Back 54

Posterior midline (comparatively low blood flow)

Front 55

What is the cause of an anal fissure?

Back 55

Hard stool passage (constipation), hyperactive sphincter, disease process (eg, Crohn's disease)

Front 56

What is a sentinel pile?

Back 56

Thickened mucosa / skin at the distal end of an anal fissure that is often confused with a small hemorrhoid

Front 57

What is the anal fissure triad for a chronic fissure?

Back 57

1. Fissure

2. Sentinel pile

3. Hypertrophied anal papilla

Front 58

What is the conservative treatment for anal fissures?

Back 58

- Sitz baths

- Stool softeners

- High fiber diet

- Excellent anal hygiene

- Topical nifedipine

- Botox

Front 59

What disease processes must be considered with a chronic anal fissure?

Back 59

- Crohn's disease

- Anal cancer

- STDs

- Ulcerative colitis

- AIDS

Front 60

What are the indications for surgery for anal fissure?

Back 60

Chronic fissure refractory to conservative treatment

Front 61

What is one surgical option for an anal fissure?

Back 61

Lateral internal sphincterotomy (LIS) - cut the internal sphincter to release it from spasm

Front 62

What is the rule of 90% for anal fissures?

Back 62

- 90% occur posteriorly

- 90% heal with medical treatment alone

- 90% of patients who undergo an LIS heal successfully

Front 63

What are perianal warts?

Back 63

Warts around the anus / perineum

Front 64

What is the cause of perianal warts?

Back 64

Condyloma acuminatum (HPV)

Front 65

What is the major risk associated with perianal warts?

Back 65

Squamous cell carcinoma

Front 66

What is the treatment of perianal warts if they are small?

Back 66

- Topical podophyllin

- Imiquimod (Aldara)

Front 67

What is the treatment of perianal warts if they are large?

Back 67

Surgical resection or laser ablation

Front 68

What are hemorrhoids?

Back 68

Engorgement of the venous plexuses of the rectum, anus, or both; with protrusion of the mucosa, anal margin, or both

Front 69

Why do we have "healthy" hemorrhoidal tisue?

Back 69

It is thought to be involved with fluid/air continence

Front 70

What are the signs/symptoms of hemorrhoids?

Back 70

Anal mass / prolapse, bleeding, itching, pain

Front 71

Which type of hemorrhoids, internal or external, are painful?

Back 71

External, below the dentate line

Front 72

If a patient has excruciating anal pain and history of hemorrhoids, what is the likely diagnosis?

Back 72

Thrombosed external hemorrhoid (treat with excision)

Front 73

What are the causes of hemorrhoids?

Back 73

- Constipation / straining

- Portal HTN

- Pregnancy

Front 74

What is an internal hemorrhoid?

Back 74

Hemorrhoid above the (proximal) dentate line

Front 75

What is an external hemorrhoid?

Back 75

Hemorrhoid below the dentate line

Front 76

What are the three "hemorrhoid quadrants"?

Back 76

1. Left lateral

2. Right posterior

3. Right anterior

Front 77

What is a "first-degree hemorrhoid"?

Back 77

Hemorrhoid that does not prolapse

Front 78

What is a "second-degree hemorrhoid"?

Back 78

Hemorrhoid prolapses with defecation but returns on its own

Front 79

What is a "third-degree hemorrhoid"?

Back 79

Hemorrhoid prolapses with defecation or any type of Valsalva maneuver and requires active manual reduction (eat fiber!)

Front 80

What is a "fourth-degree hemorrhoid"?

Back 80

Hemorrhoid prolapsed and cannot be reduced

Front 81

What is the treatment of hemorrhoids?

Back 81

- High fiber diet, anal hygiene, topical steroids, sitz baths

- Rubber band ligation (in most cases anesthetic is not necessary for internal hemorrhoids)

- Surgical resection for large refractory hemorrhoids, infrared coagulation, harmonic scalpel

Front 82

What is a "closed" vs an "open" hemorrhoidectomy?

Back 82

- Closed (Ferguson) "closes" the mucosa with sutures after hemorrhoid tissue removal

- Open (Milligan-Morgan) leaves mucosa "open"

Front 83

What are the dreaded complications of a hemorrhoidectomy?

Back 83

- Exsanguination (bleeding may pool proximally in lumen of colon w/o any signs of external bleeding)

- Pelvic infection (may be extensive and potentially fatal)

- Incontinence (injury to sphincter complex)

- Anal stricture

Front 84

What condition is a contraindication for a hemorrhoidectomy?

Back 84

Crohn's disease

Front 85

Classically, what must be ruled out with lower GI bleeding believed to be caused by hemorrhoids?

Back 85

Colon cancer (colonoscopy)