American Society for Radiation Oncology Feb 27 2025 A new clinical guideline from the American Society for Radiation Oncology (ASTRO) provides guidance on the use of radiation therapy to treat adult patients with primary squamous cell carcinoma (SCC) of the anal canal and anal margin. The guideline, ASTRO's first for anal cancer, is published in Practical Radiation Oncology . Although anal cancer is relatively rare compared with colon or rectal cancers, incidence and mortality rates have risen