Chapter 48: Anus- Anal Cancer Flashcards
Identify the following:
What is the most common carcinoma of the anus?
Squamous cell carcinoma (80%)
(Think: ASS = Anal Squamous Superior)
What cell types are found in carcinomas of the anus?
- Squamous cell carcinoma (80%)
- Cloacogenic (transitional cell)
- Adenocarcinoma/melanoma/mucoepidermal
What is the incidence of anal carcinoma?
Rare (1% of colon cancers incidence)
What is anal Bowen’s disease?
Squamous cell carcinoma in situ
How is Bowen’s disease treated?
With local wide excision
What is Paget’s disease of the anus?
Adenocarcinoma in situ of the anus
(Think: P.A. = Paget’s Adenocarcinoma)
How is Paget’s disease treated?
With local wide excision
What are the risk factors for anal cancer?
- Human papilloma virus
- condyloma
- herpes
- HIV
- chronic inflammation
- fistulae
- Crohn’s disease
- immunosuppression
- homosexuality in males
- cervical/vaginal cancer
- STDs
- smoking
What is the most common symptom of anal carcinoma?
Anal bleeding
What are the other signs/symptoms of anal carcinoma?
- Pain
- mass
- mucus per rectum
- pruritus
What percentage of patients with anal cancer is asymptomatic?
≈25%
To what locations do anal canal cancers metastasize?
Lymph nodes
liver
bone
lung
What is the lymphatic drainage below the dentate line?
Below to inguinal lymph nodes (above to pelvic chains)
Are most patients with anal cancer diagnosed early or late?
Late (diagnosis is often missed)
What is the workup of a patient with suspected anal carcinoma?
- History
- Physical exam:
- digital rectal exam
- proctoscopic exam
- colonoscopy
- Biopsy of mass
- Abdominal/pelvic CT scan
- transanal U/S
- CXR
- LFTs
Margin cancer
Anal verge out 5 cm onto the perianal skin
Canal cancer
Proximal to anal verge up to the border of the internal sphincter
How is an anal canal epidermal carcinoma treated?
NIGRO protocol:
- Chemotherapy (5-FU and mitomycin C
- Radiation
- Postradiation therapy scar biopsy 6 to 8 weeks post radiation therapy[XRT]
What percentage of patients have a “complete” response with the NIGRO protocol?
90%
What is the 5-year survival with the NIGRO protocol?
85%
What is the treatment for local recurrence of anal cancer after the NIGRO protocol?
- May repeat chemotherapy/XRT or
- salvage Abdominoperineal resection (APR)
How is a small (<5 cm) anal margin cancer treated?
Surgical excision with 1-cm margins
How is a large (>5 cm) anal margin cancer treated?
Chemoradiation
What is the treatment of anal melanoma?
Wide excision or APR (especially if tumor is large) ± XRT, chemotherapy,postoperatively
What is the 5-year survival rate with anal melanoma?
<10%
How many patients with anal melanoma have an amelanotic anal tumor?
Approximately one third, thus making diagnosis difficult without pathology
What is the prognosis of anal melanoma?
<5% 5-year survival rate
