Tumour diameter >5 cm, male sex, and lymph node involvement are associated with worse overall survival and worse disease-free survival.[60]Ajani JA, Winter KA, Gunderson LL, et al. US intergroup anal carcinoma trial: tumor diameter predicts for colostomy. J Clin Oncol. 2009 Mar 1;27(7):1116-21.
https://www.doi.org/10.1200/JCO.2008.19.6857
http://www.ncbi.nlm.nih.gov/pubmed/19139424?tool=bestpractice.com
[61]Ajani JA, Winter KA, Gunderson LL, et al. Prognostic factors derived from a prospective database dictate clinical biology of anal cancer: the intergroup trial (RTOG 98-11). Cancer. 2010 Sep 1;116(17):4007-13.
https://www.doi.org/10.1002/cncr.25188
http://www.ncbi.nlm.nih.gov/pubmed/20564111?tool=bestpractice.com
Stage 2B (>5 cm) anal squamous cell cancer was significantly associated with worse survival compared with stage 2A (2-5 cm) cancer in two cohorts (National Cancer Database [NCDB] 2004-2014 and the Surveillance, Epidemiology, and End Results [SEER] database [1988-2013]).[62]Goffredo P, Garancini M, Robinson TJ, et al. A national-level validation of the new American Joint Committee on Cancer 8th edition subclassification of stage IIA and B anal squamous cell cancer. Ann Surg Oncol. 2018 Jun;25(6):1654-60.
http://www.ncbi.nlm.nih.gov/pubmed/29572706?tool=bestpractice.com
Five-year overall survival was 72% and 69% for stage 2A versus 57% and 50% for stage 2B in the NCDB and SEER databases, respectively (P <0.001).
Overall results
The 5-year survival rates for people diagnosed with anal cancer between 2010 and 2016 were:[63]American Cancer Society. Cancer A-Z. Anal cancer survival rates. February 2022 [internet publication].
https://www.cancer.org/cancer/anal-cancer/detection-diagnosis-staging/survival-rates.html
82% for people with localised disease
66% for people with regional disease
34% for people with distant metastatic disease.
Outcome by T stage
Treatment failure increases with increasing T stage. Based on people diagnosed with anal cancer between 2008 and 2014, one study reported that, among patients with T1 anal cancer, 11% had local failure compared with 24% for those with T2, 45% for those with T3, and 43% for those with T4. There was a corresponding decrease in 5-year survival (95% for those with T1, 79% for T2, 53% for T3, and 19% for T4).[64]Peiffert D, Bey P, Pernot M, et al. Conservative management by irradiation of epidermoid cancers of the anal canal: prognostic factors of tumor control and complications. Int J Radiat Oncol Biol Phys. 1997;37:313-324.
http://www.ncbi.nlm.nih.gov/pubmed/9069302?tool=bestpractice.com
Five-year colostomy-free survival also decreases with stage.[60]Ajani JA, Winter KA, Gunderson LL, et al. US intergroup anal carcinoma trial: tumor diameter predicts for colostomy. J Clin Oncol. 2009 Mar 1;27(7):1116-21.
https://www.doi.org/10.1200/JCO.2008.19.6857
http://www.ncbi.nlm.nih.gov/pubmed/19139424?tool=bestpractice.com
[65]Gerard JP, Ayzac L, Hun D, et al. Treatment of anal canal carcinoma with high dose radiation therapy and concomitant fluorouracil-cisplatinum: long term results in 95 patients. Radiother Oncol. 1998;46:249-256.
http://www.ncbi.nlm.nih.gov/pubmed/9572617?tool=bestpractice.com
Outcome by N stage
In contrast to T stage, the impact of positive lymph nodes is less clear.
Unlike rectal cancer, inguinal lymph nodes in anal cancer are considered nodal metastasis (N+) rather than distant metastasis (M1), and patients should be treated in a curative fashion.
Node positive status has been associated with locoregional treatment failure and worse overall survival in some studies.[66]Rusten E, Rekstad BL, Undseth C, et al. Anal cancer chemoradiotherapy outcome prediction using 18F-fluorodeoxyglucose positron emission tomography and clinicopathological factors. Br J Radiol. 2019 May;92(1097):20181006.
https://www.doi.org/10.1259/bjr.20181006
http://www.ncbi.nlm.nih.gov/pubmed/30810343?tool=bestpractice.com
[67]Ajani JA, Winter KA, Gunderson LL, et al. Fluorouracil, mitomycin, and radiotherapy vs fluorouracil, cisplatin, and radiotherapy for carcinoma of the anal canal: a randomized controlled trial. JAMA. 2008 Apr 23;299(16):1914-21.
https://www.doi.org/10.1001/jama.299.16.1914
http://www.ncbi.nlm.nih.gov/pubmed/18430910?tool=bestpractice.com
[68]Glynne-Jones R, Sebag-Montefiore D, Adams R, et al. Prognostic factors for recurrence and survival in anal cancer: generating hypotheses from the mature outcomes of the first United Kingdom Coordinating Committee on Cancer Research Anal Cancer Trial (ACT I). Cancer. 2013 Feb 15;119(4):748-55.
https://www.doi.org/10.1002/cncr.27825
http://www.ncbi.nlm.nih.gov/pubmed/23011911?tool=bestpractice.com