drexel university college of medicine benign and malignant anal lesions david e. stein, m.d....

Drexel University College of Medicine

Benign and Malignant Anal Lesions

David E. Stein, M.D.

Division of Colorectal Surgery

Department of Surgery



Benign Conditions

• Rectal Prolapse/Incontinence• Anal Fissures• Anal Abscess• Anal Fistula• Hemorrhoids• Hidradenitis• Pilonidal Disease


Rectal Prolapse

• Another time• Another Place• Another Lecture• Recognize it• Surgical Repairs


Anal Fissure

• A linear tear or ulcer in the anal mucosa distal to the dentate line– Primary (majority)– Secondary (Crohn’s, trauma, infection)

• Constipation is the most common predisposing factor

• Diarrhea may also be a factor• Severe pain with defecation


Anal Fissure

• Etiology unknown– IAS overactivity

– Ischemia

• Acute Fissure– Superficial, no induration, defined margins

• Chronic Fissure– Sentinel tag, anal ulcer, hypertrophic anal papilla


Anal Fissure

• Medical Management– 85% of acute fissures will heal

– 50% of chronic fissures

• Types of Medical Therapy– Fiber

– Nitoglycerin Ointment

– Calcium Channel Blockers

– Botox Injections


Anal Fissure

• Surgical Therapy- Failed medical management– Lateral Internal Sphincterotomy

– Decreases anal canal tone

– Increases Tissue Perfusion

• Successful 95% of the time• 1% Complication rate

– incontinence


Anorectal Abscess

• Common surgical emergency• Recurrence rate of 48%• Males greater than females• Classified as follows

– Perianal– Ischiorectal– Submucosal– Intersphinteric– Supralevator


Anorectal Abscess


Anorectal Abscess

• Originate in Anal Glands• Perianal and Ischiorectal predominate (80%)• Other etiologies include IBD, septic anal fissure,

cancer, post-operative• Chief Complaint – Anal Pain• Treatment is Surgical Drainage• One third will develop chronic fistulas


Fistulas

• Communication between the anal mucosa and the perianal skin

• Most are cryptoglandular in origin– Rule out IBD/malignanct/etc

• Goodsall’s Rule– Relationship between track opening and source


Fistulas


Fistulas

• Parks Classification– Intersphinteric– Transsphinteric– Suprasphinteric– Extrasphinteric


Fistulas


Fistulas - Management

• Risks of incontinence versus benefits of therapy• Sphincter preservation if possible• Fistulotomy – opening the entire fistula track

– Superficial and intersphinteric fistulas

– Low transsphinteric fistulas

• Seton Placement– High transsphinteric fistulas

– +/- Suprasphinteric fistulas



• Setons– Cutting vs Draining– Draining setons are removed after 3-6 months– Cutting setons are tightened every two weeks in

the office

• Extrasphinteric Fistulas– Not cryptoglandular– Post-operative


Hemorrhoids

• Everyone has hemorrhoids!• Submucosal cushions comprised of connective

tissue, arterioles and venules• External vs Internal (Dentate Line)• Three positions

– Left Lateral

– Right Posterior

– Right Anterior


Hemorrhoids

• Prolapse and Induration secondary to straining, constipation and pregnancy

• Family History - 50%• Most common presentations are rectal bleeding

and prolapse• Severe pain is due to thrombosis or

strangulation/necrosis


Hemorrhoids


Hemorrhoids

• Internal– First Degree: Bleeding– Second Degree : Prolapse with spontaneous

reduction– Third Degree: Prolapse requiring manual

reduction– Fourth Degree: Irreducible Prolapse


Hemorrhoids

• Internal – Management– Small with minimal bleeding – fiber/fluids– Second and Third Degree:

• Banding/coagulation/sclerotherapy– Fourth Degree or strangulated/thrombosed

• Surgical hemorrhoidectomy


Hemorrhoids

• External– Presents as painful mass – thrombosed– Natural history is resolution over days– Clot evacuation relieves symptoms


Hidradenitis Suppurativa


Pilonidal Disease

• Acquired abscess formation in the natal cleft

• Chronic Course

• Acute Rx – drain

• Chronic– WLE

– Flaps


Premalignant and MalignantAnal Disease


Anatomy

• World Health Organization and the American Joint Committee on Cancer developed universal terminology

• Anal Canal – extends from the upper to the lower border of the internal anal sphincter (pelvic floor to anal verge)

• Mucosal lining is divided into upper (rectal), middle (transitional), and lower (squamous)


Anatomy


Anatomy

• Lymphatic drainage follows the mucosal lining

• The upper lining drains via the superior rectal lymphatics to the inferior mesenteric nodes


Anatomy

• The transitional zone (extends cephalad from the dentate line for 1cm) drains primarily cephalad via the superior rectal lymphatics with some drainage via middle and inferior rectal vessels to the internal iliac nodes

• The lower lining drains to the inguinal nodes, some secondary drainage to the internal iliacs


Anal Tumors

• Perianal, or anal margin cancers are those tumors arising below the anal canal and extending onto the adjacent skin for 5-6cm

• Perianal tumors are treated and staged as skin cancer


Incidence

• Malignant anal neoplasms account for 1-6% of all colorectal cancers

• 85% of these arise in the anal canal• Mean age of patients range from 58–67 years• Anal canal cancers have a marked female

predominance (5:1 ratio)• Perianal cancers have a marked male

predominance (4:1 ratio)


Incidence

• Increasing incidence over the past thirty years• The AIDS epidemic has accounted for the large

increase in anal cancer in males • Squamous cell carcinoma of the anal canal

accounts for more than 80% of anal cancers


Etiology and Pathogenesis

• Cigarette smoking, chronic inflammatory conditions (Crohns disease), and human papilloma virus infection have been shown to increase the risk of anal cancer

• Mechanism of HPV induced cancer parallels the genesis of cervical cancer

• 60 different HPV genotypes• 20 types infect anogenital region


Etiology and Pathogenesis

• HPV types 6 and 11 are associated with benign lesions such as warts and low grade anal intraepithelial neoplasia

• HPV types 16, 18, 31, 33, 34 and 35 are associated with high grade AIN, carcinoma in situ, and anal and cervical cancer


Staging

• TNM classification for both perianal and anal canal lesions

• T stage is based on tumor diameter, not depth of invasion

• Best staging includes careful physical examination (EUA as needed), multiple biopsies, TRUS, and CT or MRI


Screening

• Lessons learned from cervical cancer and the success of screening Papanicolaou smears may be applied to high risk groups

• High Risk Groups include – HIV negative men with a history of anal receptive

intercourse

– HIV postive men and women with CD4 counts < 500/mm3

– Women with high grade CIN


Screening

• The problem: The optimal treatment for premalignant lesions is unknown


Neoplasms of the Anal Margin

• Premalignant lesions:– AIN

– Bowen’s Disease

– Paget’s Disease

• Malignant Lesions– Squamous cell carcinoma

– Basal Cell Carcinoma

– Verrucous Carcinoma


Premalignant lesions


Bowen’s Disease

• Rare, slow growing, intraepidermal squamous cell carcinoma (carcinoma in situ)

• 5-10% may become invasive SCC• Most commonly presents in the sixth decade of

life• Originally thought to be a marker for other

malignancies• Only 102 cases reported in the literature from

1939-1995


Bowen’s Disease


Paget’s Disease

• First case of perianal Paget’s disease was reported in 1893

• Cells are probably of apocrine gland origin• Starts as a benign lesion• May progress to adenocarcinoma


Paget’s Disease


Malignant Lesions of the Anal Margin


SCC of the Anal Margin

• 5 times LESS common than SCC of the anal canal• Rolled everted edges with central ulceration• Similar to other SCC of the skin• May be found in chronic, non-healing ulcers• Mean age is 66 years at presentation



• Usually diagnosed more than two years after the onset of symptoms

• Common symptoms include a lump, bleeding, pain, discharge and itching

• 28% of patients are misdiagnosed with hemorrhoids, fissures, eczema, fistula or a benign lesion



• No clear consensus on therapy• Local excision and APR have high failure rates for

advanced cancers• For T1 well differentiated lesions, WLE vs

chemoradiation• For T2 and more advanced lesions chemoradiation

with radiation to the groin is recommended• 5 yr survival is 86-100% for T1 lesions, and drops

to 60% for T2 lesions


Basal Cell Carcinoma

• Rare – MSKCC reported 5 cases over a 25 year period

• Presents in the sixth decade, and is more common in men

• Grossly similar to cutaneous basal cell cancers, with central ulceration and irregular, raised edges

• Low invasive potential, but must be distinguished from cloacogenic tumors


Basal Cell Carcinoma

• Local excision with 1 cm margins is recommended

• Local recurrence is common (29%)• Recurrence is treated with re-excision• APR and radiotherapy are reserved for large,

extensive lesions


Verrucous Carcinoma

• aka: giant condyloma acuminatum• aka: Buschke-Lowenstein Tumor• Presents as a large, slow growing, painful wart

like growth that is soft, with a cauliflower like appearance

• Histologically benign, but clinically malignant


Verrucous Carcinoma


Verrucous Carcinoma

• Continuous progression and expansion with erosion and pressure necrosis of the underlying tissue

• No metastases have been reported• Wide local excision is the treatment of choice• If the tumor involves the anal sphincters, APR is

indicated• Chemoradiation has not been used to date


Neoplasms of the Anal Canal

• Squamous cell carcinoma• Adenocarcinoma• Small cell / Neuroendocrine carcinoma• Malignant Melanoma• Sarcomas• Lymphomas


SCC of the Anal Canal

• Squamous cell or epidermoid cancers comprise 80% of anal cancers

• Morphologic types include keratinizing SCC, nonkeratinizing SCC, basaloid (cloacogenic) tumors, and SCC with mucus microcysts

• Morphology does not alter prognosis or therapy• These tumors are more aggressive and have a

worse prognosis than their anal margin counterparts



• Most patients present with bleeding, pain, or tenesmus

• Lesions are usually felt on digital examination and are tender, indurated, and ulcerated

• EUA, biopsies, TRUS and CT/MRI are used for diagnosis and staging

• 76% of patients are initially misdiagnosed with a benign condition



• Poor results with WLE/APR• Nigro showed no residual tumor in 22 of 24 APR

specimens after “neoadjuvant” chemoradiation followed by resection

• Nigro protocol is the standard of care for SCC of the anal canal



Nigro Protocol – 32 daysExternal Beam Radiation:

• 3000 cGy to primary carcinoma and pelvic/inguinal lymph nodes starting day 1 (200cGy/day)

Systemic Chemotherapy:• 5-FU 1000mg/m2/day continuous infusion days 1-4

and 28-32• Mitomycin-C 15mg/m2 IV bolus day 1

Nigro ND DC&R 1984



• 80-93% complete regression rates• 70-90% five year survival rates have been

reported• APR resulted in 24-62% 5yr survival with a 27-

50% recurrence rate



• APR is indicated for nonresponders, anorectal complications of therapy and recurrent disease

• The management of residual scars is somewhat controversial, although most authors suggest local excision


Adenocarcinoma

• Most commonly a very distal rectal adenocarcinoma with caudal spread

• True anal canal adenocarcinomas are rare• There is an association with HPV• Tumors arising from chronic fistulas or

longstanding Crohn’s disease have been reported


Adenocarcinoma

• In general these tumors have a poor prognosis, with aggressive spread to inguinal and pelvic nodes

• APR with preoperative chemoradiation therapy is the treatment of choice


Neuroendocrine Tumors

• Anal canal carcinoids may arise from neuroectodermal cells of the anal transition zone

• Tumors are rare and do not secrete active peptides or neurotransmittors

• Lesions less than 2cm may be treated by excision, and larger lesions by APR

• Chemoradiation is investigational


Melanoma

• Rare, accounting for 1-3% of all melanomas• Anal canal is 3rd most common site following skin

and eyes• Female to male ratio is 2:1, with an average age of

63 years at presentation• The tumor may arise from above or below the

dentate line


Melanoma


Melanoma

• Rectal bleeding, a mass in the anal canal and pain are the most common signs and symptoms

• Average size of tumor at presentation is 4cm• Pigmented polypoid lesions which may be

confused with thrombosed hemorrhoids• 40-70% are amelanotic, with sheets of anaplastic

cells


Melanoma

• Most studies have shown no benefit to APR over wide local excision

• Standard of care is WLE with 1 cm margins• MSKCC series spanning 64 years found a survival

advantage with APR in young, node negative patients with smaller tumors – Brady, Kavolius Quan DCR, 1995

• Overall prognosis is poor regardless of therapy


Sarcomas

• Rare, usually leiomyosarcomas• Bleeding, pain and perianal mass are common

signs and symptoms, the sphincters are usually involved

• High grade lesions, size greater than 6cm and previous incomplete excision worsen the prognosis

• Standard therapy is APR


Summary

• Anal Margin Tumors are treated with WLE• SCC of the Anal Canal is treated with the Nigro

Protocol• Adenocarcinoma of the anal canal is treated with

APR• Consult a colorectal surgeon for all of those

benign problems….


The End

drexel university college of medicine benign and malignant anal lesions david e. stein, m.d....

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