Intensity-Modulated Radiation Therapy for Anal Cancer: Toxicity versus Outcomes

Cancer of the anal canal is an uncommon malignancy, with an estimated 5,290 cases diagnosed in the United States in 2009; however, its incidence has been increasing over the past several decades (www.cancer.gov). Historically, first-line therapy was an abdominoperineal resection (APR), resulting in a permanent colostomy. Long-term cure rates following resection alone have varied in the literature, but results as high as 71% have been reported. For most patients, however, avoidance of radical resection and permanent colostomy placement are highly desirable.[1]

Table 1Nigro and colleagues at Wayne State University pioneered the non-operative treatment paradigm for anal canal cancers.[2,3] Their initial investigation consisted of three patients treated with approximately 30 Gy radiation therapy (RT) with concurrent 5-fluorouracil (5FU) and mitomycin C (MMC). Two patients underwent planned APR with no residual disease demonstrated by pathologic assessment and the third patient declined surgical intervention, with no disease relapse in follow-up. This important preliminary data spawned numerous investigations of non-operative management of anal canal cancer.

source: CancerNetwork