Case 8.7 – Anal Fissures, Cancers and STIs [SDL]

Further History and Examination:

• Complete GIT history - bowel habits, dietary factors, previous episodes, family history
• Thorough GIT examination - abdominal examination
• Visual and digital rectal examination - inspect for fissures, tags, hemorrhoids; assess sphincter tone
• Proctoscopy - if tolerated, to visualize anal canal and lower rectum

Clinical Presentation of Anal Fissures:

Symptoms

• Most common cause of severe localized anorectal pain
• Pain dramatically increased during bowel movements
• Pain typically starts with defecation and may persist from minutes to hours, disproportionate to the size of the lesion
• Often associated with streaks of blood in the stool
• Bleeding usually minimal and bright red if present

Pathophysiology

• Anal fissures are painful linear tears in the lining of the anal canal, below the level of the dentate line
• Most often located posteriorly in both sexes, but women also present with anterior anal fissures
• They occur in the posteroanterior plane because pelvic muscular support is weakest along this axis
• Ectopic lateral fissures suggest an unusual diagnosis (e.g. Crohn's disease, leukaemia, sexually transmitted disease, malignancy)
• Fissures are secondary to local trauma, either from constipation or excessive diarrhea

Examination Findings

• On examination, gentle retraction of the buttocks will reveal a tear at the anal verge
• Rectal examination is usually associated with severe pain and significant sphincter spasm thus not often well tolerated - consider whether formal per rectal examination will alter management or not
• In cases of chronic recurrent anal fissures, the classic triad is pathognomonic:
  • External skin tag
  • A fissure exposing the internal sphincter fibres
  • A hypertrophied anal papilla at the level of the dentate line

Treatment of Anal Fissures:

Treatment is based on the duration and severity of the symptoms.

Conservative Management (Acute Fissures)

• Acute anal fissures usually respond to conservative treatment
• Avoidance of diarrhea or constipation
• Bulk laxatives to keep bowel movements atraumatic
• Mild non-narcotic analgesic
• Sitz baths may be helpful

Medical Management

• If not resolving, GTN ointment (Rectogesic) is helpful
  • Reduces muscle spasm
  • Aids healing by increased local blood flow
  • However, headaches can be a side effect
• Botulinum toxin (Botox) is used in some centres instead of, or before surgery

Surgical Management

• If conservative treatment fails, or the fissure is chronic, surgery is recommended
• In uncomplicated cases, the operative choice is lateral internal sphincterotomy
  • A small portion of the internal sphincter is cut
  • Releases the sphincter spasm
  • Relieves pain and allows the fissure to heal
  • The operation carries a small risk of minor incontinence
  • Greater than 95% cure rate

Anal Cancer Presentation:

Epidemiology and Types

• Perianal and anal canal malignancies are rare, with less than 1% of the incidence of colorectal cancer
• There are essentially two types of anal cancers:
  • Epidermoid carcinoma (a generic type that includes squamous cell, basaloid, cloacogenic, mucoepidermoid, and transitional carcinomas)
  • Malignant melanoma
• The anus is the third most common site for malignant melanoma (after the skin and eyes)

Clinical Presentation

• Either type of malignancy may cause pain, bleeding, or a lump
• Delay in diagnosis is often a consequence of both patient and physician neglect

Malignant Melanoma Specific Features

• Lymph node involvement and widespread metastases are common at presentation
• Diagnosis often delayed because of lack of pigment in these lesions (amelanotic melanoma)

Examination

• Examination should include palpation of the inguinal lymph nodes

Diagnosis

• Diagnosis depends on incision biopsy (could be excision biopsy if small less than 2cm)

Treatment Principles for Anal Carcinoma:

Historical Treatment

• In the past, abdominoperineal resection and permanent colostomy were the mainstays of treatment for both types of cancer

Current Treatment for Epidermoid Anal Cancer

• Now almost completely abandoned surgery in favour of combined modality chemotherapy and radiation therapy
• Using protocol of pelvic radiation with infusion of 5-FU and mitomycin C, sometimes referred to as Nigro regime after American surgeon who introduced same in late 1970s
• 5-year survival rates now approximately 85%

Role of Surgery in Epidermoid Cancer

• Surgery (abdominoperineal excision of rectum) indicated in cases where residual tumour is present after radiation and chemotherapy
• Recurrence of anal canal cancer after combined modality therapy requires (salvage) abdominoperineal excision of rectum

Lymph Node Management

• Prophylactic inguinal node dissection is not recommended (unless clinically palpable nodes are present) because of high morbidity associated with this procedure
• Synchronous inguinal node metastasis is an ominous sign and survival rates are poor
• Conversely, metachronous inguinal lymph node involvement has a better prognosis
• Inclusion of the inguinal lymph nodes in radiation field decreases the incidence of metachronous lymph node involvement without adding much morbidity

Malignant Melanoma Treatment

• For malignant melanoma, the prognosis is dismal, regardless of the treatment
• For good-risk patients, abdominoperineal resection is a reasonable option to maximize survival

Clinical Presentation of Common Anorectal Sexually Transmitted Diseases:

More than 20 sexually transmitted diseases can be present in the anorectal area. Therefore it is important to inquire about a complete sexual history in patients with anorectal symptoms.

Condition	Clinical Features	Treatment
Anal Condylomas (HPV)	Caused by human papilloma virus Most common anorectal infection affecting homosexual men May also be seen in heterosexual men and women - and even children Transmission at birth and by close contact with infected patients has been reported In men: lesions found perianally, intraanally, on the penis and in the urethra In women: also in the vulva, vagina, cervix and urethra Condylomata acuminata are pink or white papillary lesions Vary in size from 1mm to large cauliflower-like lesions They bleed easily Difficulty in perianal hygiene may lead to pruritus ani Discomfort and pain often present	Various topical caustic agents (e.g. podophyllin) Local destruction (electrocoagulation, diathermy, liquid nitrogen cryotherapy, laser) techniques High recurrence rates (10% to 50%) with all local treatments Interferon can be used New HPV vaccines promising - now available in Australia
Anal Chlamydial Infection	Among the most common sexually transmitted disease Chlamydial proctitis increasing in homosexual men	Tetracycline or doxycycline Erythromycin in certain patients
Anal Gonorrhea (Neisseria gonorrhoeae)	Neisseria gonorrhoeae infections of the rectum account for as many as 50% of the cases of gonorrhoea in homosexual men Most patients have nonspecific complaints, including pruritus, tenesmus, and hematochezia Sigmoidoscopy shows: thick, yellow mucopurulent discharge; rectal mucosa ranges from normal to erythematous and edematous Culture and gram stain are used for organism identification Evaluation and follow up require cultures of the urethra, rectum and pharynx	Ceftriaxone 250 mg IM single stat dose
Anal HSV (Herpes Simplex Virus Type 2)	Herpes simplex virus type 2 causes herpetic proctitis Infection acquired by direct inoculation Approximately 15% of homosexual men with rectal symptoms have only this virus identified by rectal culture Symptoms begin 4 to 28 days after inoculation: majority of patients have pain and burning worsened by bowel movements Some patients have lumbosacral radiculopathy syndrome: sacral paraesthesia, impotence, lower abdominal/buttock/thigh pain, urinary dysfunction Lesions include: vesicles with red areolae, ruptured vesicles, and aphthous ulcers Usual locations: perianal skin, anal canal, and lower rectum Patients who are seen in the relapsing stage may report a history of crusting lesions followed by healing Scrapings for cytologic examination show intranuclear inclusion bodies and giant cells	Treatment aimed at relieving symptoms: sitz baths, topical anaesthetics, and analgesics Acyclovir (famvir) has benefit in the acute and relapse phases Continuous suppressive therapy is warranted only in the most severe cases