66-Year-Old Man With Locally Advanced Pancreatic Cancer Undergoing Chemotherapy:(A)使用阳性口腔造影剂的增强CT轴向图像，用于监测治疗反应。检查临床解释为未显示转移性疾病。非盲法回顾性影像学检查显示肠袢附近有微小网膜结节(箭头)。对比剂检查肠道充盈情况良好。两组盲法回溯性读者均检出结节。(B) 2个月后CT增强轴位图显示结节轻微增大(箭头)和几个新结节(箭头)，确认为未发现的恶性沉积。Image courtesy of American Roentgen Ray Society (ARRS), American Journal of Roentgenology (AJR)
April 27, 2022 —According to ARRS’American Journal of Roentgenology(AJR), the selection of oral contrast agent and optimization of bowel preparation for oncologiccomputed tomography(CT) could help avoid potentially severe clinical consequences of missed malignant deposits.
“CT has suboptimal NPV for malignant deposits in intraabdominal nonsolid organs,” wrote corresponding authorBenjamin M. Yehof theUniversity of California, San Francisco. “Compared to neutral material, positive oral contrast material improves detection, particularly with adequate bowel filling.”
Yeh and team’s retrospective study included 265 patients (133 men, 132 women; median age, 61 years) who underwent anabdominopelvic CTexamination where the report did not suggest presence of malignant deposits and subsequent CT examination within 6 months where the report indicated at least one unequivocal malignant deposit. Examinations used positive (iohexol; n=100) or neutral (water; n=165) oral agents. While reviewing images to assess visibility of deposits, a board-certified abdominal radiologist also assessed adequacy of bowel filling with oral contrast material.
NPV of CT for detection of malignant deposits in intraabdominal nonsolid organs was 65.8% for examinations using positive oral contrast material with adequate bowel filling, 45.2% for positive oral contrast material with inadequate bowel filling (p=.07), and 35.2% for neutral oral contrast material regardless of adequacy of bowel filling (p=.002).
“Results may differ when studying other types of contrast material regimens,”the authors of thisAJRarticle noted, including barium-based, hyperosmolar iodine, sugar-alcohol neutral, or experimental dark oral agents.
For more information:www.arrs.org
August 11, 2022
