Abstract：Objective: To improve the accuracy of preoperative diagnosis of sacrococcygeal yolk sac tumor in children by correlating the CT or MR imaging features with histopathology. Methods: CT or MR imaging findings of sacrococcygeal yolk sac tumor in 21 cases confirmed by surgery and pathology were retrospectively reviewed. Results: All the 21 tumors appeared as soft-tissue masses and most of them were well-defined. The tumors were heterogeneous in terms of density or signal intensity and were always associated with different degree of necrotic and cystic change area. Among them, 7 cases showed blood vessels enhancement on contrast-enhanced CT or MRI, 6 cases showed small patch intratumor hemorrhage. All the 21 cases surrounded and invaded the coccyx, with 7 cases extending into the canalis vertebralis. What is more, multiple lung metastases were found in 9 cases and bone metastases were shown in 2 cases. All the 12 cases demonstrated hetergeneous hyperintensity on DWI, with the ADC value was between (0.63~1.32)×10-3 mm2/s. Serum AFP level of all the 21 yolk sac tumors increased. Conclusion: Sacrococcygeal yolk sac tumors always occurs in infants and young children, especially less than 3 years old, and are prone to hemorrhage, necrosis and cystic change. CT or MRI examination combined with serum AFP examination can improve the accuracy of preoperative diagnosis, and also can determine the range of tumor involvement, which is important for selection for clinical treatment and prognosis assessment.
陆征海，丁 茗，蔡 静，崔雪娥，朱景雨，朱锦勇，汪登斌. 儿童骶尾部卵黄囊瘤的影像学表现[J]. 中国临床医学影像杂志, 2016, 27(3): 198-201.
LU Zheng-hai, DING Ming, CAI Jing, CUI Xue-e, ZHU Jing-yu, ZHU Jin-yong, WANG Deng-bin . Imaging findings of sacrococcygeal yolk sac tumor in children. JOURNAL OF CHINA MEDICAL IMAGING, 2016, 27(3): 198-201.
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