Systemic chemotherapy remains the mainstay of treatment for patient with metastatic anal cancer. The National Comprehensive Cancer Network (NCCN) Guidelines currently recommend cisplatin and 5FU chemotherapy as first-line treatment of metastatic squamous cell carcinoma (SCC). This is largely based on a study of 19 patients treated with cisplatin 100 mg/m2 and infusional 5FU 1 gm/m2/day over 5 days with a 66% response rate; there was 1 complete response and 11 partial responses in addition to 4 patients with stable disease. The actuarial survival was 62.2% at 1 year and 32.2% at 5 years, and the median survival was 34.5 months]. There have also been a number of case reports demonstrating a benefit with the cisplatin/5FU combination. This is the best researched, although not extensively supported, regimen for anal cancer.
Recently the oral fluoropyrimidine capecitabine(Xeloda) has been substituted for 5FU in a number of solid tumours, and, extrapolating from this data, many oncologists use capecitabine with cisplatin rather than 5FU. This has a number of advantages for patients, including ease of administration and possibly greater efficacy. Unfortunately, however, there is no literature support for this substitution.
D. Cunningham, N. Starling, S. Rao et al., “Capecitabine and oxaliplatin for advanced esophagogastric cancer,” New England Journal of Medicine, vol. 358, no. 1, pp. 36–46, 2008.
P. Pfeiffer, J. P. Mortensen, B. Bjerregaard et al., “Patient preference for oral or intravenous chemotherapy: a randomised cross-over trial comparing capecitabine and Nordic fluorouracil/leucovorin in patients with colorectal cancer,” European Journal of Cancer, vol. 42, no. 16, pp. 2738–2743, 2006.
Alice Dewdney and Sheela Rao Metastatic Squamous Cell Carcinoma of the Anus: Time for a Shift in the Treatment Paradigm? ISRN OncologyVolume 2012 (2012)
NCCN, Anal -6, 2012
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