Anal squamous cell carcinoma: An evolution in disease and management

Table 1 7^th edition of the American joint Committee on Cancer TNM Staging

Primary tumor (T)
Tx	Primary tumor cannot be assessed
Tis	Carcinoma in situ
T1	Tumor < 2 cm in greatest dimension
T2	Tumor between 2 and 5 cm in greatest dimension
T3	Tumor > 5 cm in greatest dimension
T4	Tumor invading adjacent organs
Regional lymph nodes (N)
Nx	Regional nodes cannot be assessed
N0	No regional lymph node metastasis
N1	Metastasis in the perirectal nodes
N2	Metastasis in unilateral internal iliac and/or inguinal nodes
N3	Metastasis bilateral internal iliac or inguinal nodes
Distant metastasis (M)
M0	No distant metastasis
M1	Distant metastasis
Stage
0	Tis	N0	M0
I	T1	N0	M0
II	T2	N0	M0
	T3	N0	M0
IIIA	T1	N1	M0
	T2	N1	M0
	T3	N1	M0
	T4	N0	M0
IIIB	T4	N1	M0
	Any T	N2	M0
IV	Any T	N3	M0
	Any T	Any N	M1

Adapted from Edge SB, Byrd DR, Compton CC, Fritz AG, Greene FL, Trotti A. AJCC Cancer Staging Manual. 7^th edition. New York: Springer, 2009.

Table 2 Treatment of anal intraepithelial neoplasia

Therapy	Pro	Con	Ref.
Watchful waiting	Avoids the morbidity of other therapies	Missed opportunity to potentially cure patient	[7]
	Low risk of interval development of carcinoma (for low-grade)	Need for close surveillance and reliable patient
Topical imiquimod	Response rate of 48%-86%	Burning, irritation, variable patient compliance	[14-16]
		Recurrence or new lesions in untreated areas
Topical 5-florouracil	High response rate, up to 90%	High recurrence rate, up to 50%	[17,18]
Wide local excision	Recurrence rates as low as 13% reported	Significant morbidity of anal stenosis, wound healing and incontinence	[19-21]
Targeted therapy with HRA	Evidence to prevent progression to anal cancer	High rate of persistent or recurrent disease in HIV positive patients	[22-24]
	Avoid anal stenosis and incontinence

HRA: High-resolution anoscopy; HIV: Human immunodeficiency virus.