[Instruments for radiotherapy of esophageal neoplasms: present status and future prospects].
D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D004938:Esophageal Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D009502:Neutrons; D011878:Radiotherapy / Q000295:instrumentation* / Q000639:trends; D011882:Radiotherapy, High-Energy