title: Accuracy of CT Colonography for Detection of Polypoid and Nonpolypoid Neoplasia by Gastroenterologists and Radiologists: A Nationwide Multicenter Study in Japan.
abstract: The objective of this study was to assess prospectively the diagnostic accuracy of computer-assisted computed tomographic colonography (CTC) in the detection of polypoid (pedunculated or sessile) and nonpolypoid neoplasms and compare the accuracy between gastroenterologists and radiologists.
  
  
  
  This nationwide multicenter prospective controlled trial recruited 1,257 participants with average or high risk of colorectal cancer at 14 Japanese institutions. Participants had CTC and colonoscopy on the same day. CTC images were interpreted independently by trained gastroenterologists and radiologists. The main outcome was the accuracy of CTC in the detection of neoplasms ≥6 mm in diameter, with colonoscopy results as the reference standard. Detection sensitivities of polypoid vs. nonpolypoid lesions were also evaluated.
  
  
  
  Of the 1,257 participants, 1,177 were included in the final analysis: 42 (3.6%) were at average risk of colorectal cancer, 456 (38.7%) were at elevated risk, and 679 (57.7%) had recent positive immunochemical fecal occult blood tests. The overall per-participant sensitivity, specificity, and positive and negative predictive values for neoplasms ≥6 mm in diameter were 0.90, 0.93, 0.83, and 0.96, respectively, among gastroenterologists and 0.86, 0.90, 0.76, and 0.95 among radiologists (P<0.05 for gastroenterologists vs. radiologists). The sensitivity and specificity for neoplasms ≥10 mm in diameter were 0.93 and 0.99 among gastroenterologists and 0.91 and 0.98 among radiologists (not significant for gastroenterologists vs. radiologists). The CTC interpretation time by radiologists was shorter than that by gastroenterologists (9.97 vs. 15.8 min, P<0.05). Sensitivities for pedunculated and sessile lesions exceeded those for flat elevated lesions ≥10 mm in diameter in both groups (gastroenterologists 0.95, 0.92, and 0.68; radiologists: 0.94, 0.87, and 0.61; P<0.05 for polypoid vs. nonpolypoid), although not significant (P>0.05) for gastroenterologists vs. radiologists.
  
  
  
  CTC interpretation by gastroenterologists and radiologists was accurate for detection of polypoid neoplasms, but less so for nonpolypoid neoplasms. Gastroenterologists had a higher accuracy in the detection of neoplasms ≥6 mm than did radiologists, although their interpretation time was longer than that of radiologists.
authors: Japanese CTC Society, Boston, Massachusetts, USA.|3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors: Koichi
authors: K
authors: Nagata
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama, Kanagawa, Japan.
authors: Shungo
authors: S
authors: Endo
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology, Nagasaki Kamigoto Hospital, Shinkamigoto, Minamimatsuura, Nagasaki, Japan.
authors: Tetsuro
authors: T
authors: Honda
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Radiology Section, Nagasaki Kamigoto Hospital, Shinkamigoto, Minamimatsuura, Nagasaki, Japan.
authors: Takaaki
authors: T
authors: Yasuda
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology, Otaru Kyokai Hospital, Otaru, Hokkaido, Japan.
authors: Michiaki
authors: M
authors: Hirayama
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology, Otaru Kyokai Hospital, Otaru, Hokkaido, Japan.
authors: Sho
authors: S
authors: Takahashi
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology, Hokkaido Gastroenterology Hospital, Sapporo, Hokkaido, Japan.
authors: Takashi
authors: T
authors: Kato
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Internal Medicine, Hokkaido Gastroenteology Hospital, Sapporo, Hokkaido, Japan.
authors: Shoichi
authors: S
authors: Horita
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology and Hepatology, Japan Community Health Care Organization (JCHO) Hokkaido Hospital (formerly known as Hokkaido Social Insurance Hospital), Sapporo, Hokkaido, Japan.
authors: Ken
authors: K
authors: Furuya
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Radiology, Japan Community Health Care Organization (JCHO) Hokkaido Hospital (formerly known as Hokkaido Social Insurance Hospital), Sapporo, Hokkaido, Japan.
authors: Kenji
authors: K
authors: Kasai
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology, Kawasaki Medical School Hospital, Kurashiki, Okayama, Japan.
authors: Hiroshi
authors: H
authors: Matsumoto
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology, Kawasaki Medical School Hospital, Kurashiki, Okayama, Japan.
authors: Yoshiki
authors: Y
authors: Kimura
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Radiology, Jichi Medical University Hospital, Shimotsuke, Tochigi, Japan.
authors: Kenichi
authors: K
authors: Utano
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Radiology, Jichi Medical University Hospital, Shimotsuke, Tochigi, Japan.
authors: Hideharu
authors: H
authors: Sugimoto
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Clinical Laboratory and Endoscopy, Tokyo Women's Medical University Medical Center East, Tokyo, Japan.
authors: Hiroyuki
authors: H
authors: Kato
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Clinical Laboratory and Endoscopy, Tokyo Women's Medical University Medical Center East, Tokyo, Japan.
authors: Rieko
authors: R
authors: Yamada
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, USA.
authors: Junta
authors: J
authors: Yamamichi
authors: Department of Medical Statistics and Information, Kameda Medical Center Makuhari, Chiba-city, Chiba, Japan.
authors: Takeshi
authors: T
authors: Shimamoto
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Radiology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors: Yasuji
authors: Y
authors: Ryu
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Radiology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors: Osamu
authors: O
authors: Matsui
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Center for Digestive Diseases, Tonan Hospital, Sapporo, Hokkaido, Japan.
authors: Hitoshi
authors: H
authors: Kondo
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Center for Digestive Diseases, Tonan Hospital, Sapporo, Hokkaido, Japan.
authors: Ayako
authors: A
authors: Doi
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Digestive Disease Center, Akita Red Cross Hospital, Akita City, Akita, Japan.
authors: Taro
authors: T
authors: Abe
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Digestive Disease Center, Akita Red Cross Hospital, Akita City, Akita, Japan.
authors: Hiro-O
authors: HO
authors: Yamano
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Center for Gastroenterology and IBD Research, Hamamatsu South Hospital, Hamamatsu, Shizuoka, Japan.
authors: Ken
authors: K
authors: Takeuchi
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Center for Gastroenterology and IBD Research, Hamamatsu South Hospital, Hamamatsu, Shizuoka, Japan.
authors: Hiroyuki
authors: H
authors: Hanai
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Radiology, St Luke's International Hospital, Tokyo, Japan.
authors: Yukihisa
authors: Y
authors: Saida
authors: Japanese CTC Society, Boston, Massachusetts, USA.|Department of Gastroenterology, St Luke's International Hospital, Tokyo, Japan.
authors: Katsuyuki
authors: K
authors: Fukuda
authors: 3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors: Janne
authors: J
authors: Näppi
authors: Japanese CTC Society, Boston, Massachusetts, USA.|3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors: Hiroyuki
authors: H
authors: Yoshida
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging* / Q000473:pathology; D000368:Aged; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000473:pathology; D003111:Colonic Polyps / Q000000981:diagnostic imaging* / Q000473:pathology; D023881:Colonography, Computed Tomographic; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005243:Feces / Q000737:chemistry; D005260:Female; D000072102:Gastroenterologists; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007120:Immunochemistry; D007564:Japan; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D000072177:Radiologists; D012680:Sensitivity and Specificity
chemical_list: D006454:Hemoglobins