Radiation Dose Associated with Common Computed Tomography Examinations and the Associated Lifetime Attributable Risk of Cancer

Abstract

Background-Use of computed tomography (CT) for diagnostic evaluation has increased dramatically over the past two decades. Even though CT is associated with substantially higher radiation exposure than conventional x-rays, typical clinical doses are not known. We sought to estimate the radiation dose associated with common CT studies in clinical practice; assess variation in dose across types of studies, patients, and institutions; and quantify the potential cancer risk associated with these examinations. Methods-Retrospective cross-sectional study describing radiation dose associated with the 11 most common types of diagnostic CT studies performed on 1,119 consecutive adult patients at four San Francisco Bay Area institutions between January 1 and May 30, 2008. We estimated lifetime attributable risks of cancer by study type from these measured doses.

Secondary malignancies among nonseminomatous germ cell tumor cancer survivors

“…Intrinsically, the prevention of 73 excess second malignancies per 10,000 individuals is a meaningful number, especially in the face of a mortality rate that may be as high as 50% among those who develop a malignancy associated with irradiation from CT imaging. 7,8 Indeed, we contend that the excess incidence of second malignancy in patients with clinical stage I disease (73 patients) and a mortality rate of 50% (36 deaths) is significant when the cancers-specific mortality rate for those undergoing RPLND is 0.5% (50 patients).…”

“…7,8 That is, by way of the radiation dose they deliver, CT scans pose long-term risks that may outweigh the benefits of avoiding surgery. In a simulated model, Tarin et al calculated that the lifetime attributable risk of developing a second malignancy could be as high as 2% and that the relative risk was 15 among patients who comply with the NCCN guidelines compared with patients who undergo a single CT scan after diagnosis.…”

Minimization of radiation exposure due to computed tomography in inflammatory bowel disease

“…Similarly, exposure to ionizing radiation in early life is believed to magnify the risk of tumour induction [5]. It has been reported that patients who are diagnosed with Crohn's disease as children are more likely to receive higher lifetime cumulative radiation exposures [2,5,6]. Children undergoing CT receive greater organ doses than adults, and, in children, most organs are more sensitive to radiationinduced cancer than in adults [5].…”

Open-Source Radiation Exposure Extraction Engine (RE3) with Patient-Specific Outlier Detection

“…CT accounts for almost half of medical procedure-related radiation exposure to Americans each year [1] and the risk of cancer associated with CT radiation has been extensively discussed [2][3][4][5][6][7][8][9][10][11][12]. Imaging modalities are now required to report radiation exposure metrics [13] and some states are requiring hospitals to keep radiation records [14].…”