Anus, C49 P325-334 Flashcards
ANATOMY
Identify the following:
P325 (picture)
- Anal columns
- Dentate line
- Rectum
- External sphincter
- Internal sphincter
- Levator ani muscle
ANAL CANCER
What is the most common
carcinoma of the anus?
P326
Squamous cell carcinoma (80%)
Think: ASS = Anal Squamous Superior
ANAL CANCER
What cell types are found in
carcinomas of the anus?
P326
- Squamous cell carcinoma (80%)
- Cloacogenic (transitional cell)
- Adenocarcinoma/melanoma/
mucoepidermal
ANAL CANCER
What is the incidence of
anal carcinoma?
P326
Rare (1% of colon cancers incidence)
ANAL CANCER
What is anal Bowen’s disease?
P326
Squamous cell carcinoma in situ
Think: B.S. = Bowen Squamous
ANAL CANCER
How is Bowen’s disease
treated?
P326
With local wide excision
ANAL CANCER
What is Paget’s disease of
the anus?
P326
Adenocarcinoma in situ of the anus
Think: P.A. = Paget’s Adenocarcinoma
ANAL CANCER
How is Paget’s disease
treated?
P326
With local wide excision
ANAL CANCER
What are the risk factors for
anal cancer?
P326
Human papilloma virus, condyloma, herpes, HIV, chronic inflammation (fistulae/Crohn’s disease) immunosuppression, homosexuality in males, cervical/ vaginal cancer, STDs, smoking
ANAL CANCER
What is the most common
symptom of anal carcinoma?
P326
Anal bleeding
ANAL CANCER What are the other signs/symptoms of anal carcinoma? P326
Pain, mass, mucus per rectum, pruritus
ANAL CANCER What percentage of patients with anal cancer is asymptomatic? P326
≈25%
ANAL CANCER
To what locations do anal
canal cancers metastasize?
P326
Lymph nodes, liver, bone, lung
ANAL CANCER What is the lymphatic drainage below the dentate line? P327
Below to inguinal lymph nodes (above to
pelvic chains)
ANAL CANCER Are most patients with anal cancer diagnosed early or late? P327
Late (diagnosis is often missed)
ANAL CANCER What is the workup of a patient with suspected anal carcinoma? P327
History Physical exam: digital rectal exam, proctoscopic exam, and colonoscopy Biopsy of mass Abdominal/pelvic CT scan, transanal U/S CXR LFTs
ANAL CANCER
Define:
Margin cancer
P327
Anal verge out 5 cm onto the perianal skin
ANAL CANCER
Define:
Canal cancer
P327
Proximal to anal verge up to the border
of the internal sphincter
ANAL CANCER How is an anal canal epidermal carcinoma treated? P327
NIGRO protocol: 1. Chemotherapy (5-FU and mitomycin C) 2. Radiation 3. Postradiation therapy scar biopsy (6–8 weeks post XRT)
ANAL CANCER What percentage of patients have a “complete” response with the NIGRO protocol? P327
90%
ANAL CANCER
What is the 5-year survival
with the NIGRO protocol?
P327
85%
ANAL CANCER What is the treatment for local recurrence of anal cancer after the NIGRO protocol? P327
May repeat chemotherapy/XRT or
salvage APR
ANAL CANCER
How is a small (<5 cm) anal
margin cancer treated?
P327
Surgical excision with 1-cm margins
ANAL CANCER
How is a large (>5 cm) anal
margin cancer treated?
P327
Chemoradiation
ANAL CANCER
What is the treatment of
anal melanoma?
P328
Wide excision or APR (especially if
tumor is large) +-/ XRT, chemotherapy,
postoperatively
ANAL CANCER
What is the 5-year survival
rate with anal melanoma?
P328
<10%
ANAL CANCER How many patients with anal melanoma have an amelanotic anal tumor? P328
Approximately one third, thus making
diagnosis difficult without pathology
ANAL CANCER
What is the prognosis of
anal melanoma?
P328
<5% 5-year survival rate
FISTULA IN ANO
What is it?
P328
Anal fistula, from rectum to perianal skin
FISTULA IN ANO
What are the causes?
P328
Usually anal crypt/gland infection (usually
perianal abscess)
FISTULA IN ANO
What are the signs/symptoms?
P328
Perianal drainage, perirectal abscess,
recurrent perirectal abscess, “diaper
rash,” itching
FISTULA IN ANO What disease should be considered with fistula in ano? P328
Crohn’s disease
FISTULA IN ANO
How is the diagnosis made?
P328
Exam, proctoscope
FISTULA IN ANO
What is Goodsall’s rule?
P328 (picture)
Fistulas originating anterior to a transverse
line through the anus will course straight
ahead and exit anteriorly, whereas those
exiting posteriorly have a curved tract
FISTULA IN ANO
How can Goodsall’s rule be
remembered?
P329 (picture)
Think of a dog with a straight nose
anterior) and curved tail (posterior
FISTULA IN ANO
What is the management of
anorectal fistulas?
P329
- Define the anatomy
- Marsupialization of fistula tract
(i.e., fillet tract open) - Wound care: routine Sitz baths and
dressing changes - Seton placement if fistula is through
the sphincter muscle
FISTULA IN ANO
What is a seton?
P329 (picture)
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
FISTULA IN ANO What percentage of patients with a perirectal abscess develop a fistula in ano after drainage? P330
≈50%
FISTULA IN ANO How do you find the internal rectal opening of an anorectal fistula in the O.R.? P330
Inject H(2)O(2) (or methylene blue) in external opening—then look for bubbles (or blue dye) coming out of internal opening!
FISTULA IN ANO
What is a sitz bath?
P330
Sitting in a warm bath (usually done after
bowel movement and TID
PERIRECTAL ABSCESS
What is it?
P330
Abscess formation around the anus/rectum
PERIRECTAL ABSCESS
What are the signs/symptoms?
P330
Rectal pain, drainage of pus, fever,
perianal mass
PERIRECTAL ABSCESS
How is the diagnosis made?
P330
Physical/digital exam reveals perianal/
rectal submucosal mass/fluctuance
PERIRECTAL ABSCESS
What is the cause?
P330
Crypt abscess in dentate line with spread
PERIRECTAL ABSCESS
What is the treatment?
P330
As with all abscesses (except simple liver
amebic abscess) drainage, sitz bath,
anal hygiene, stool softeners
PERIRECTAL ABSCESS What is the indication for postoperative IV antibiotics for drainage? P330
Cellulitis, immunosuppression, diabetes,
heart valve abnormality
PERIRECTAL ABSCESS What percentage of patients develops a fistula in ano during the 6 months after surgery? P330
≈50%
ANAL FISSURE
What is it?
P330
Tear or fissure in the anal epithelium
ANAL FISSURE
What is the most common
site?
P330
Posterior midline (comparatively low blood flow)
ANAL FISSURE
What is the cause?
P330
Hard stool passage (constipation),
hyperactive sphincter, disease process
(e.g., Crohn’s disease)
ANAL FISSURE
What are the signs/symptoms?
P331
Pain in the anus, painful (can be
excruciating) bowel movement, rectal
bleeding, blood on toilet tissue after
bowel movement, sentinel tag, tear in the
anal skin, extremely painful rectal exam,
sentinel pile, hypertrophic papilla
ANAL FISSURE
What is a sentinel pile?
P331
Thickened mucosa/skin at the distal end
of an anal fissure that is often confused
with a small hemorrhoid
ANAL FISSURE
What is the anal fissure triad
for a chronic fissure?
P331 (picture)
- Fissure
- Sentinel pile
- Hypertrophied anal papilla
ANAL FISSURE
What is the conservative
treatment?
P331
Sitz baths, stool softeners, high fiber diet,
excellent anal hygiene, topical nifedipine,
Botox®
ANAL FISSURE What disease processes must be considered with a chronic anal fissure? P331
Crohn’s disease, anal cancer, sexually
transmitted disease, ulcerative colitis,
AIDS
ANAL FISSURE
What are the indications for
surgery?
P331
Chronic fissure refractory to conservative
treatment
ANAL FISSURE
What is one surgical option?
P331
Lateral internal sphincterotomy (LIS)—
cut the internal sphincter to release it
from spasm
ANAL FISSURE
What is the “rule of 90%”
for anal fissures?
P331
90% occur posteriorly
90% heal with medical treatment alone
90% of patients who undergo an LIS heal
successfully
PERIANAL WARTS
What are they?
P332
Warts around the anus/perineum
PERIANAL WARTS
What is the cause?
P332
Condyloma acuminatum (human papilloma virus)
PERIANAL WARTS
What is the major risk?
P332
Squamous cell carcinoma
PERIANAL WARTS
What is the treatment if
warts are small?
P332
Topical podophyllin, imiquimod (Aldara®)
PERIANAL WARTS
What is the treatment if
warts are large?
P332
Surgical resection or laser ablation
HEMORRHOIDS
What are they?
P332
Engorgement of the venous plexuses of
the rectum, anus, or both; with protrusion
of the mucosa, anal margin, or both
HEMORRHOIDS
Why do we have “healthy”
hemorrhoidal tissue?
P332
It is thought to be involved with fluid/air
continence
HEMORRHOIDS
What are the signs/
symptoms?
P332
Anal mass/prolapse, bleeding, itching, pain
HEMORRHOIDS
Which type, internal or
external, is painful?
P332
External, below the dentate line
HEMORRHOIDS If a patient has excruciating anal pain and history of hemorrhoids, what is the likely diagnosis? P332
Thrombosed external hemorrhoid
treat by excision
HEMORRHOIDS
What are the causes of
hemorrhoids?
P332
Constipation/straining, portal
hypertension, pregnancy
HEMORRHOIDS
What is an internal
hemorrhoid?
P332
Hemorrhoid above the (proximal)
dentate line
HEMORRHOIDS
What is an external
hemorrhoid?
P332
Hemorrhoid below the dentate line
HEMORRHOIDS
What are the three
“hemorrhoid quadrants”?
P332
- Left lateral
- Right posterior
- Right anterior
Classification by Degrees
Define the following terms for internal hemorrhoids:
First-degree hemorrhoid
P333 (picture)
Hemorrhoid that does not prolapse
Classification by Degrees
Define the following terms for internal hemorrhoids:
Second-degree hemorrhoid
P333 (picture)
Prolapses with defecation, but returns on
its own
Classification by Degrees
Define the following terms for internal hemorrhoids:
Third-degree hemorrhoid
P333 (picture)
Prolapses with defecation or any type of Valsalva maneuver and requires active manual reduction (eat fiber!)
Classification by Degrees
Define the following terms for internal hemorrhoids:
Fourth-degree hemorrhoid
P334
Prolapsed hemorrhoid that cannot be
reduced
Classification by Degrees
What is the treatment?
P334
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
Classification by Degrees
What is a “closed” vs. an
“open” hemorrhoidectomy?
P334
Closed (Ferguson) “closes” the mucosa with
sutures after hemorrhoid tissue removal
Open (Milligan-Morgan) leaves mucosa
“open”
Classification by Degrees What are the dreaded complications of hemorrhoidectomy? P334
Exsanguination (bleeding may pool proximally in lumen of colon without any signs of external bleeding) Pelvic infection (may be extensive and potentially fatal) Incontinence (injury to sphincter complex) Anal stricture
Classification by Degrees What condition is a contraindication for hemorrhoidectomy? P334
Crohn’s disease
Classification by Degrees Classically, what must be ruled out with lower GI bleeding believed to be caused by hemorrhoids? P334
Colon cancer (colonoscopy)