title: The true role of external-beam irradiation in the initial treatment of cancer of the rectum.
mesh_terms: D000368:Aged; D002986:Clinical Trials as Topic; D003131:Combined Modality Therapy; D005500:Follow-Up Studies; D006801:Humans; D011879:Radiotherapy Dosage; D012004:Rectal Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery