The neoplastic potential of gastric irradiation. IV. Risk estimates.
No significant tumor increase was found in the initial analysis of patients irradiated for peptic ulcer and followed through 1962. A preliminary study was undertaken 22 years later to estimate the risk of cancer due to gastric irradiation for peptic ulcer disease. A population of 2,049 irradiated patients and 763 medically managed patients has been identified. A relative risk of 3.7 was found for stomach cancer and an initial risk estimate of 5.5 X 10(-6) excess stomach cancers per person rad was calculated. A more complete follow-up is in progress to further elucidate this observation and decrease the ascertainment bias; however, preliminary data are in agreement with the Japanese atomic bomb reports.
D005500:Follow-Up Studies; D006801:Humans; D009381:Neoplasms, Radiation-Induced / Q000209:etiology*; D010437:Peptic Ulcer / Q000532:radiotherapy*; D011878:Radiotherapy / Q000009:adverse effects*; D012306:Risk; D013274:Stomach Neoplasms / Q000209:etiology*