title: Squamous-cell carcinoma of the anus: progress in radiotherapy treatment.
abstract: Chemoradiotherapy is the standard-of-care treatment of squamous-cell carcinoma of the anus (SCCA), and this has not changed in decades. Radiation doses of 50-60 Gy, as used in many phase III trials, result in substantial late morbidities and fail to control larger and node-positive tumours. Technological advances in radiation therapy are improving patient outcomes and quality of life, and should be applied to patients with SCCA. Modern techniques such as intensity-modulated radiotherapy (IMRT), rotational IMRT, image-guided radiotherapy using cone-beam CT, and stereotactic techniques have enabled smaller margins and highly conformal plans, resulting in decreased radiation doses to the organs at risk and ensuring a shorter overall treatment time. In this Perspectives article, the use of novel approaches to target delineation, optimized radiotherapy techniques, adaptive radiotherapy, dose-escalation with external-beam radiotherapy (EBRT) or brachytherapy, and the potential for modified fractionation are discussed in the context of SCCA.
authors.affiliation: Department of Clinical Oncology, Mount Vernon Centre for Cancer Treatment, Mount Vernon Hospital, Rickmansworth road, Northwood, Middlesex HA6 2RN, UK.
authors.forename: Rob
authors.initials: R
authors.lastname: Glynne-Jones
authors.affiliation: National Cancer Centre, 11 Hospital Drive, Singapore 169610, Singapore.
authors.forename: David
authors.initials: D
authors.lastname: Tan
authors.affiliation: Department of Clinical Oncology, Mount Vernon Centre for Cancer Treatment, Mount Vernon Hospital, Rickmansworth road, Northwood, Middlesex HA6 2RN, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Hughes
authors.affiliation: Department of Clinical Oncology, Mount Vernon Centre for Cancer Treatment, Mount Vernon Hospital, Rickmansworth road, Northwood, Middlesex HA6 2RN, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Hoskin
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001005:Anus Neoplasms / Q000532:radiotherapy*; D001685:Biological Factors / Q000627:therapeutic use; D001918:Brachytherapy / Q000379:methods; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D059248:Chemoradiotherapy / Q000379:methods; D017326:Clinical Trials, Phase III as Topic; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D058958:Organs at Risk; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods; D061766:Proton Therapy / Q000379:methods; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided / Q000379:methods; D016032:Randomized Controlled Trials as Topic
chemical_list: D001685:Biological Factors
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