ANAL DISEASES.pptx surgical management

Surgical diseases

1. B ENIGN AND MALIGNANT ANAL CONDITIONS HU NAAYA PROFESSOR OF SURGERY/CONSULTANT SURGEON UNIVERSITY OF MAIDUGURI/UNIVERSITY OF MAIDUGURI TEACHING HOSPITAL, MAIDUGURI

2. ANATOMY OF THE ANAL CANA

3. ANATOMY OF THE ANAL CANAL

4. INTRODUCTION A natomy of the anal canal 4cm in length D irected downward and backward from anorectal ring to anal orifice R elation A nterior – perineal body & bulbar urethra (males), lower vagina (female) L ateral – ischiorectal fossa both sides P osterior – coccyx M uscular wall of the anus constitute the sphincters responsible for continence A t the mid portion of the anal canal is the pectinate or dentate line

5. INTRODUCTION A t this point, valve-like folds enclosing crypts openinig cephalad G lands opening into the crypts may be infected => anorectal abscess => anorectal fistulae A rterial supply is from the superior and inferior rectal arteries F ewer arterioles in the posterior midline of the anal acanal => poor blood supply => site for anal fissure C omparison of the anal canal above and below are as shown below

6. INTRODUCTION A bove the dentate line E pithelium = columnar (adenocarcinoma) A rterial supply = superior & inferior rectal arteries V enous drainage = to portal system L ymphatics = to inferior mesenteric & internal iliac LN N erve supply = autonomic L esions = painless B elow the dentate line E pithelium = squamous (SCC) A rterial supply = superior & inferior rectal arteries V enous drainage = to systemic system L ymphatic = to inguinal lymph nodes N erve supply = somatic L esions = painful (fissure,abscess, haematoma, fistula, thrombosed haemorrhoid s )

7. B ENIGN AND MALIGNANT ANAL CONDITIONS Common anorectal conditions include: Haemorrhoids, Perianal pruritus, Anal fissures, Functional rectal pain, Perianal abscess, Condyloma, Rectal prolapse, and Fecal incontinence Fistula-in- ano Anal cancers

8. HAEMORRHOID

9. LEARNING OBJECTIVES D efine haemorrhoid P athophysiology of haemorrhoid C lassify haemorrhoid U nderstand diagnosis and treatment of haemorrhoid

10. HAEMORRHOID Dilatation or varices of the vessels of the superior and/or inferior rectal plexuses of veins Common human affliction from the dawn of history Bipedal position predisposes to the condition Exact incidence in developing countries has not been determined Symptomatic Haemorrhoid occur in about 4% of the general population

11. AETIOLOGY Predisposing factors Hereditary, Age Sex Cathartic abuse Diarrhoea Constipation Obesity Rise in intra abdominal pressure Bipedal position

12. PATHOPHYSIOLOGY Increase pressure at rectal ampulla Congestion of haemorrhoidal plexuses by compressing the haemorrhoidal veins (low pressure vessels) Arterial flow from the rectal arteries continue Progressive mucosal prolapse with each bowel motion Gradual elongation of the mucosal suspensory ligaments Fully developed permanently prolapsed Haemorrhoid These can not fully explain the development of haemorrhoid

13. SURGICAL PATHOLOGY Varicose submucosal branches of superior and inferior haemorrhoidal vein constituting the internal and external haemorrhoidal plexuses are congregated into the 3 primary positions: Left lateral haemorrhoidal branch -> 3 o’clock position Right posterior branch -> 7 o’clock position Right anterior branch -> 11 o’clock position This is depending on the termination of the superior rectal artery

14. SURGICAL PATHOLOGY Classification of haemorrhoids based on degree of prolapse First degree haemorrhoid – no prolapse, short mucosal suspensory ligament, bleeding as main feature Second degree haemorrhoid – suspensory ligament present, prolapse, reduces spontaneously. Third degree haemorrhoid – longer mucosal suspensory ligament, prolapse, reduced manually Fourth degree haemorrhoid – permanently prolapsed

15. CLINICAL FEATURES Passage of bright red blood, not mixed with stool, may even come after the faeces.(1 st degree) Prolapse on defaecation Mucoid discharges Peri-anal irritation Soiling of under clothing Pain – rarely unless complicated Thrombosis Congestion Oedema Concomitant fissure

16. CLINICAL FEATURES Examination Prolapse in the primary positions -3,7,11 o’clock with patient in lithotomy position Haemorrhoid not usually palpable unless thrombosed There may be associated anal fissure Proctoscopy will show the haemorrhoids Sigmoidoscopy to rule out other lesions such as colonic tumour Differential diagnosis Anorectal cancer Rectal prolapse Anal fissure Peri anal haematoma Condylomas

17. COMPLICATIONS OF HAEMORRHOID Thrombosis Gangrene Peri anal abscess Anaemia Portal pyaemia

18. THROMBOSED EXTERNAL HAEMORRHOID

19. TREATMENT Conservative measures High fibre diet High in take of fluids Methyl cellulose Liquid paraffin Sitz bath Injection sclerotherapy 5% phenol in almon oil Inject 3-5mls into the visualized pedicle of the haemorrhoid About 2 haemorrhoid at a time

20. TREATMENT Rubber band ligation Rubber band placed the base of the haemorrhoid Special gun used for the procedure – Baron’s gun Suitable for 1 st and 2 nd degree haemorrhoid Avoid pain by placing the band 0.5-1cm above the dentate line Necrosis occur in 24-48 hours 2mls of 1% xylocaine can be injected into the banded haemorrhoid to reduce pain Not more than 2 haemorrhoids to be banded at any particular time Result excellent in 70% of cases

21. TREATMENT Cryotherapy Rapid freezing followed by thawing => tissue necrosis Liquid nitrogen at -160⁰c cryoprobe is placed on each haemorrhoid – freeze for 3 minutes Discharge is profuse after the procedure requiring 2-4 pads per day for 4 weeks. Infrared coagulation Suitable for 1 st and 2 nd degree haemorrhoid Applied at the base of the haemorrhoid using proctoscope Similar results as; rubber band ligation, cryotherapy and injection sclerotherapy

22. TREATMENT Haemorrhoidectomy Open haemorrhoidectomy (Milligan & Morgan) 2 nd , 3 rd , and 4 th degree haemorrhoid 7-10 days hospitalization pre-operative preparation Under spinal or general anaesthesia , in lithotomy position Routine cleaning and draping done, 4-finger anal stretch done The 3 haemorrhoids are displayed with artery forceps The haemorrhoids are dissected to the dentate line and the pedicles transfixed and ligated. Wound left open The excised and anal canal packed with sofratulle gauze Pack removed 24 hours, sitz bath, liquid paraffin, high residue diet, analgesics, antibiotics

23. TREATMENT Complications of haemorrhoidectomy Retention of urine – sympathetic sphincter spasm due pain, adequate analgesia, urethral catheterization Haemorrhage – secondary haemorrhage from infection 7-14 days post op. Wound infection Anal stenosis – over zealous excision of the haemorrhoid (anal dilatation, anoplasty) Staple haemorrhoidopexy (Longo Technique) Suitable for prolapsed haemorrhoid This entails: Resection of the redundant prolapsed mucosa Interrupting the terminal branches of the superior rectal artery -> reducing arterial inflow Lifting the mucosa higher up into the anal canal ->correcting the prolapse Less pain and short hospital stay

24. TREATMENT Suture less haemorrhoidectomy New technique Tissue fusion produced by melting of collagen Suture less Closed Early return to work

25. ANAL FISSURE S mall mucosal tear in the long axis of the anal canal I n the lower third of the canal H igh analmaximum resting pressure and anal sphincter tone

26. PATHOGENESIS T ear in the posterior midline O verstretching of the mucosa during passage of hard stool I n 10% of women and 1% of men tear in the anterior midline A cute tear may heal spontaneously B ut may progress to the chronic stage

27. CLINICAL FEATURES M en > Females A nal pain during defaecation, lasting for hours thereafter P ain makes patient fear to go to defaecate => hard stool => more pain when defaecating => viscious cycle B leeding A nal discharge => pruritus S entinel pile R ectal examination is too painful and should be deferred.

28. TREATMENT Conservative H igh fibre diet X yloproct L iquid parafin S itz bath C hemical sphincterotomy N itic oxide donor (topical Glyceryl Trinitrate {GTN}) C alcium channel blocker (topical Diltiazem or Nifedipine) Botulinum toxin A

29. TREATMENT S phincter stretching (Lord’s dilatation) – lowering of anal resting and squeeze pressure L ateral internal sphincterotomy F issurectomy +/- anal advancement flap

30. P ERIANAL HAEMATOMA H aematoma at the anal verge R upture of venule in the external haemorrhoidal plexus C aused by sudden increase in veous pressure – defaecation, coughing, lifting of heavy weight or during delivery T reatment M ay resolve spontaneously, rupture or may become infected leading to peri anal abscess.

31. A NAL INCONTINENCE I nvoluntary loss of flatus or faeces I t is a social and hygiene problem

32. CAUSES C ongenital M ental deficiency N eurological disease (meningomyelocele) A bnormalities of anus and rectum A quired T rauma O verstretching of the external sphincter by prolapse (rectum or haemorrhoid) N eoplasms N eurological diseases (head inury) F alse incontinence (faecal impaction, diarrhoea)

33. C LINICAL FEATURES C ommoner in women and elderly >65 years of age I nability to control flatus or faeces S oiling of perineum and underwears P ositive aetiological history P er rectal examinations L oss of sphincter tone L oss of rectal sensation P rolapse – rectum, haemorrhoid

34. I NVESTIGATIONS A nal sonography M RI T he maximum mean resting pressure is low

35. TREATMENT P rophylaxis – avoid overstretching of the anal sphincter N onoperative – daily enemas to empty the rectum S acral nerve stimulation O perative R epair of the anal sphincter (over lappingsphincter repair) T ransplatation of gracilis muscles T hiersch operation C olostomy

36. PRURITUS ANI I ntractable itching of the peri anal skin U ncommon in the tropics C an be primary/idiopathic or secondary

37. PRURITUS ANI P rimary pruritus ani S everal theories I rritation of the peri anal skin by faecal contamination A llergic phenomenon due to sensitivity to items in diet P sychogenesis has been considered in patients whose attacks consides with periods of stress or tension

38. PRURITUS ANI S econdary pruritus ani M ay be associated with the following conditions L ocal anorectal conditions associated with discharge (anal fistula/fissure, anal papilloma/condylomata, prolaps haemorrhoid s /rectum) L ack of good peri anal hygiene P arasitic infestation M ycotic (fungal) infection D iabetes mellitus D ermatological causes – psoriasis etc.

39. C LINICAL FEATURES I tching M ay related to a particular kind of food E xcoriations M oist perineum I nvestigations F asting blood sugar S tool m/c/s S kin scraping for fungal studies S kin biopsy

40. T REATMENT T reat any underlying cause I mprove perineal hygiene A nti histamine

41. ANORECTAL ABSCESS

42. LEARNING OBJECTIVES Define anorectal abscess D escribe the aetiology of anorectal abscesses T ypes of anorectal abscesses T reatment of anorectal abscesses M edical S urgical

43. ANORECTAL ABSCESSES Abscess formation is common in the tissues surrounding anorectal spaces Most common organisms are: E. coli Bacteroides Proteus vulgaris Streptococci Some clostridia welcii Most the infections are polymicrobial

44. AETIOLOGY Anorectal abscess occur in potential spaces which are filled with lipo-areola tissue These spaces are: Intersphincteric Ischiorectal Peri-anal Intermuscular Submucous Supralevator compartment Anorectal abscesses and fistulae in most cases are different phases of the same disease process

45. AETIOLOGY Acute phase -> abscess Chronic phase -> fistula Anorectal abscesses arise from the anal glands in 75% of cases Penetration of the rectal wall by sharp objects -> fish bone Infected Haemorrhoid, or haemorrhoidectomy wound Cutaneous boils Blood borne infections Pre-disposing factors Diabetes RVI Immunosuppressive therapy

46. CLASSIFICATION OF ANORECTAL ABSCESSES Based on the anorectal space involved Perianal Ischiorectal Submucous Pelvirectal (Supralevator) Intersphincteric Intermuscular May also be classified into: Supralevator Infra levator

47. CLASSIFICATION OF ANORECTAL ABSCESSES Infralevator Intersphincteric Extra sphincteric Intrasphinctric Depending on the relation to levator ani muscle and the anal sphincter Commonest is the peri-anal abscesses followed by ischiorectal abscesses

48. CLINICAL FEATURES Commoner in men than women Pain in the anal region, severe, throbbing Made worse by sitting, walking, coughing or straining Examination may reveal – swelling, tenderness, redness, if abscess is superficial in location. Deep seated abscess may only give induration and tenderness. Constitutional symptoms Pyrexia Anorexia Diarrhoea Lower abdominal pain may be present

49. PERIANAL ABSCESS

50. INVESTIGATIONS Blood sugar estimation is very important as it may be the predisposing factor RVS – to rule out immunosuppression Specimen for M/C/S Full blood count Urea, electrolytes and creatinine Other investigations as may be indicated

51. TREATMENT Prompt and adequate incision and drainage Cruciate incision is made for the drainage Cavity must be deroofed and loculi broken with finger to ensure adequate drainage Peri-operative analgesia – must be adequate Broad spectrum antibiotics Sitz bath 80% heal within 2-3 weeks Prognosis is good when adequate and proper incision is done

52. FISTULA-IN-ANO

53. LEARNING OBJECTIVES D efine fistula in ano P athophysiology of fistula in ano C lassification of fistula in ano D iagnosis of fistula in ano T reatment of fistul in ano

54. FISTULA-IN-ANO A fistula is an abnormal communication between 2 epithelial surfaces Line by granulation tissue In the of fistula-in- ano – connection is between the anal or rectal mucosa to the perineal skin

55. AETIOLOGY Anorectal abscess and fistula-in- ano are different phases of the same disease process Their pathogenesis is similar to a large extent Most anorectal fistulae originate from the anal crypts at the pectinate line Pyogenic infection of the crypts -> cryptitis => abscess May also arise from badly drained anorectal abscess. Granulomatous conditions – TB, amoebiasis, actinomycosis, ulcerative colitis, Crohn's disease etc., Other causes Carcinoma Post haemorrhoidectomy

56. CLASSIFICATION OF FISTULA-IN-ANO Fistulae are classified according to their position relative to the anorectal ring (responsible for continence) Classified into: Low fistula High fistula Low fistula Subcutaneous Submucous intermuscular

57. CLASSIFICATION OF FISTULA-IN-ANO High fistula Uncommon Commonly iatrogenic or secondary colorectal or pelvic conditions Internal opening penetrates through or opens above anorectal ring These are: Pelvirectal High Intersphincteric High submucous

58. CLASSIFICATION OF FISTULA-IN-ANO Park’s classification Intersphincteric (most common) Trans-sphincteric –connects the Intersphincteric space to the ischiorectal fossa Suprasphincteric – tract loops over the external sphincter and perforate the levator Extra sphincteric – tract passes through rectum to perianal skin external to the sphincter complex

59. FISTULA-IN-ANO

60. CLINICAL FEATURES OF FISTULA-IN-ANO Recurrent perianal discharge (seropurulent material) Occasionally flatus and faeces Starts with perianal swelling (which discharged spontaneously) Soiling of underwear Intermittent Pain occasionally External opening (s) is/are seen Openings are usually elevated, indurated and sometimes inflamed

61. CLINICAL FEATURES OF FISTULA-IN-ANO Salmon- Goodsall’s law: Imaginary line drawn across the midpoint of the anal orifice dividing the orifice into anterior and posterior halves. Fistulae with their openings behind the imaginary line tend to take a curved course terminating in an opening in the midline posteriorly, while those with openings anterior to the line will take a direct straight course to open in line with the external opening

62. INVESTIGATIONS Radiological Fistulogram CXR-ray to rule out TB Swab for M/C/S Proctosigmoidoscopy to exclude Crohn’s Ulcerative colitis Lymphogranuloma TB actinomycosis

63. a  Plain X-ray pelvis (AP view) demonstrating gas shadow on the right perianal and gluteal region (white arrow).  b  X-ray fistulogram (Deshpande’s technique) of the same patient showing abscess cavity filled with radio-opaque contrast extending towards right gluteal region (white arrow) with gas-filled in the rectum (yellow arrow)

64. DIFFERENTIAL DIAGNOSIS Hidradenitis suppurativa Colo-perineal fistula Urethro-perineal fistula (watering Can perineum) Bartholin's cyst Infected sebaceous cyst Folliculitis

65. TREATMENT General measures Control infection Maintain anorectal function Operative treatment depends on the type Principles of treatment Identify the entire length of the tract and its ramifications (using methylene blue or gentian violet dye) Adequate drainage or removal of the entire tract Avoid damage to the anorectal ring

66. TREATMENT Low fistula Fistulotomy – lay the entire tract open and allow to heal by granulation Fistulectomy – remove the entire tract and either allow to granulate or close the wound park’s operation – lay open the tract and in addition do internal sphincterotomy High fistula Avoid injury to the anorectal ring => prevent incontinence If there chronic inflammation – treat Diversionary colostomy may be needed Two stage operation – lay open the lower tract and put a seton in the upper tract (silk or nylon) NB – all excised tissues must be sent to histology => malignant transformation,

67. PROGNOSIS 40% recurrence Inadequate surgery Bad post operative management Usually last case on the list and done by the inexperienced

68. A nal cancers

69. EPIDEMIOLOGY AND RISK FACTORS Squamous cell carcinoma of the anus is rare and least prevalent GI malignancy & accounts for only 1 - 2% of all large bowel malignancy. Ratio of 1:2 for men to women with median age at diagnosis is 60 yrs. Geographical variation - highest in Caucasian female lowest in Asian males

70. RISK FACTORS HPV infection. HIV seropositivity and low CD 4 count (twice) Cigarette smoking Anoreceptive intercourse (homosexual male 15 times) Immune suppression following transplant Anal warts.

71. P REVENTION Vaccine prevention- two vaccines- best long term approach for reducing long term risk. Boys 11-12 yrs. Girls 13 to 26 yrs.

72. NATURAL HISTORY Most anal cancers are believed to arise from precancerous changes(i.e. AIN) of the anal canal and peri anal skin epithelium High-grade AIN -> Squamous cell cancers in most instances. However, it has been estimated that approximately 5% of cases with AIN IlI progress to invasive cancer over multiyear period. Squamous cell cancers spread.

73. WHO Classification of Anal Cancer ANAL CANAL S quamous cell carcinoma K eratinizing (below dentate line) Nonkeratinizing (above dentate line) B asaloid (transitional) A denocarcinoma R ectal type O f anal glands W ithin anorectal fistula S mall cell carcinoma undifferentiated ANAL MARGIN S quamous cell carcinoma G iant condyloma B asal cell carcinoma O thers (melanoma) B owen’s disease (SCC in situ) P aget’s disease (intraepithelial adenocarcinoma)

74. STAGING PRIMARY TUMOR (T) TX Primary tumor cannot be assessed T0 No evidence of primary tumor Tis Carcinoma in situ T1 Tumor =2 cm in greatest dimension T2 Tumor >2 cm but =5 cm in greatest dimension T3 Tumor >5 cm in greatest dimension T4 Tumor of any size invades adjacent organ(s) (e.g., vagina, urethra, bladder) Direct invasion of the rectal wall, perirectal skin, subcutaneous tissue, or the sphincter muscle(s) is not classified as T4

75. STAGING REGIONAL LYMPH NODES (N) NX Regional lymph nodes cannot be assessed N0 No regional lymph node metastasis N1 Metastasis in perirectal lymph node(s) N2 Metastasis in unilateral internal iliac and/or inguinal lymph node(s) N3 Metastasis in perirectal and inguinal lymph nodes and/or bilateral internal iliac and/or inguinal lymph node

76. AJCC STAGE GROUPS Stage I - T1 N0 M0 Stage II - T2 N0 M0 T3 N0 M0 Stage IIIA T1 NI M0 T0 N1 M0 T3 N1 M0 TA N0 M0 Stage IIIB T4 NI M0 Any T N3 M0 Any T N2 M0 Stage IV Any T Any N M1

77. PROGNOSIS 5 year survival T1 - 86 percent T2 - 86 percent T3 - 60 percent T4 - 45 percent N0 - 76 percent N+ - 54 percent

78. PROGNOSTIC FACTORS Tumor size >5 cm, lymph nodes involvement, male sex are associated with poor prognosis. High expression of p53 associated with decreased DES. Also local control rates are lower with increased p53 expression. High level of Ki 67 - longer DFS.

79. CLINICAL PRESENTATION AND WORKUP Rectal bleeding- 45% of patients Pain or sensation of mass- 30% No symptoms- 20% Pruritus ani or bleeding plaques associated with anal margin skin cancers- Paget's disease. Sensation of mass or fullness and tenesmus Physical exam - per rectal and nodes. Biopsy- used to differentiate squamous cell (anal ca) from adenocarcinoma (rectal ca) .

80. I NVESTIGATIONS CT scan EUS or MRI PET scan

81. C ATEGORIES OF ANAL CANCERS It follows that, two distinct categories of tumours arise in the anal region. Tumours that develop from mucosa (columnar, transitional, or squamous) are true anal canal cancers tumours That arise from skin at or distal to the squamous-mucocutaneous junction are termed anal margin tumours

82. T REATMENT SQUAMOUS CELL CARCINOMA (80%) W ide local excision (tumour < 2 cm) C hemoradiation P rimary treatment option C ontrol most of the lesions of the anal canal M itomycin C + 5FU + Radiation with 4500 cGy in 20 fractions (start 3 days after chemo) R adiotherapy without chemtherapy P articularly in elderly patients A bdominoperineal resection of the rectum (APR).

83. Radical resection For intermediate-stage primary anal canal cancer who can tolerate radiation therapy or chemoradiation Incontinent because of irreversible damage of the sphincters Anovaginal fistula Prior pelvic radiation treatment (most frequently for carcinoma of the cervix) Active inflammatory bowel disease affecting the rectum or anal region Failure of chemoradiation or radiation and less frequently, complications of the initial treatment.

84. SALVAGE SURGERY Salvage Surgery APR = abdominoperineal resection Pelvic exenteration = multiviseral resection with urinary and faecal diversion Salvage surgery is recommended in patient with chronically persistent disease or recurrence. Salvage APR is associated with five-year survival rates from 30 to 70%, with DFS (Disease free survival) ranging from 30 to 40%.

85. FACTORS ASSOCIATED WITH POOR OVERALL SURVIVAL AFTER SALVAGE SURGERY. FACTORS Tumor size >5 cm, inguinal lymph node involvement, positive surgical margin, male sex, adjacent organ involvement are the factors associated with poor overall survival after salvage surgery.

86. Adenocarcinomas Comprise about 5% of cancers of the anal canal. Small female preponderance. The majority develop in rectal mucosa, which extends below the upper muscular boundary of the canal. No recognized association with high-risk HPV or immunosuppression. The most useful prognostic factors are T category and N category. Overall 5-year survival rates following all treatments have generally been less than 50%.

87. A DENOCARCINOMA Locoregional control is problematic. Risk of distant metastases higher than for squamous cell cancers Treated similarly to adenocarcinomas which arise in the rectum with surgery remaining as a cornerstone therapy and neoadjuvant radiation therapy or combined modality therapy generally implemented in patients with T3 or T4 and /or N+ disease

88. Melanoma of anal canal It's a rare disease, 1% of all malignant melanoma & 0.5%of all anal malignancy. Bleeding per rectum is most common presentation.  Surgery is the cornerstone for the treatment of anal melanoma, traditionally surgeons use more radical approach in form of APR with radical lymph nodes dissection Kiran et al 109 patients, reported no significant difference b/w patient treated by APR or local resection.

89. Anal Margin Cancers Anal margin cancers includes the area extending from the anal verge radially 5cm outward on perianal skin. More common in 7" and 8" decade with slight female preponderance. Treat similar to skin cancer. WLE (wide local excision) for T1 and N0 can be excised with a 1-cm margin. T3 and T4 lesions- radiation to both inguinal regions and the pelvis, along with 5-FU and mitomycin C.  APR should be reserved for patients with recurrent disease following chemoradiation or recurrence not amenable to local excision.

90. Anal Margin Cancers The regional nodes for the perianal skin are the inguinal nodes. Perirectal or pelvic node metastases are very uncommon. The risk of inguinal node metastases is about 10%, associated mainly with category T3 or T4 tumours, or poorly differentiated cancers. Elective inguinal nodal irradiation has been suggested for those categories only.

91. B owen’s and paget’s diseases About half the cases of anal Paget's disease are associated with a synchronous or metachronous internal malignancy, often a colorectal adenocarcinoma. High local recurrence rate. May become invasive. Wide local excision, with intraoperative microscopic control of margins.

92. B owen’s and paget’s diseases Local recurrence can often be managed by further local excision. Other less-established treatments Topical chemotherapy Topical immune modifiers such as imiquimod Photodynamic therapy. Radiation therapy, or radiation and chemotherapy reserved for patients with recurrent or invasive disease in whom adequate excision would entail sacrifice of anorectal function. Abdominoperineal resection may be necessary to control extensive or recurrent disease.

93. T hank you for listening