Masaya Kawaguchi1, Hiroki Kato2, Yuichiro Hatano3, Hiroyuki Tomita3, Akira Hara3, Natsuko Suzui4, Tatsuhiko Miyazaki4, Tatsuro Furui5, Ken-Ichirou Morishige5, Masayuki Matsuo1. 1. Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan. 2. Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan. hkato@gifu-u.ac.jp. 3. Department of Tumor Pathology, Gifu University School of Medicine, Gifu, Japan. 4. Department of Pathology, Gifu University School of Medicine, Gifu, Japan. 5. Department of Obstetrics and Gynecology, Gifu University School of Medicine, Gifu, Japan.
Abstract
PURPOSE: To assess MR imaging findings of low-grade serous carcinoma (LGSC) of the ovary compared with those of serous borderline tumor (SBT). METHODS: Twenty-four patients with histopathologically proven 7 LGSCs and 25 SBTs who underwent preoperative MR imaging were included. We retrospectively reviewed MR images and compared MR findings between the two pathologies. RESULTS: The predominantly solid lesions were marginally more frequent in LGSCs than in SBTs (43% vs. 8%, p = 0.057). All predominantly cystic LGSCs were multilocular cystic lesions with mural nodules. Predominantly solid LGSCs exhibited pure solid masses in 2 of 3 and solid masses with intratumoral cysts in 1 of 3. Papillary growth pattern with internal branching was observed only in 18 of 25 SBTs. Signal intensity ratio on T2-weighted images (4.48 ± 1.55 vs. 8.40 ± 3.53, p < 0.01) and apparent diffusion coefficient (ADC) values (1.12 ± 0.21 vs. 1.73 ± 0.27 × 10-3 mm2/s, p < 0.01) of solid components was significantly lower in LGSCs than in SBTs. CONCLUSION: Compared with SBTs, lower signal intensity on T2-weighted images and lower ADC values were characteristic features of solid components in LGSCs. Papillary growth pattern with internal branching was not observed in LGSCs.
PURPOSE: To assess MR imaging findings of low-grade serous carcinoma (LGSC) of the ovary compared with those of serous borderline tumor (SBT). METHODS: Twenty-four patients with histopathologically proven 7 LGSCs and 25 SBTs who underwent preoperative MR imaging were included. We retrospectively reviewed MR images and compared MR findings between the two pathologies. RESULTS: The predominantly solid lesions were marginally more frequent in LGSCs than in SBTs (43% vs. 8%, p = 0.057). All predominantly cystic LGSCs were multilocular cystic lesions with mural nodules. Predominantly solid LGSCs exhibited pure solid masses in 2 of 3 and solid masses with intratumoral cysts in 1 of 3. Papillary growth pattern with internal branching was observed only in 18 of 25 SBTs. Signal intensity ratio on T2-weighted images (4.48 ± 1.55 vs. 8.40 ± 3.53, p < 0.01) and apparent diffusion coefficient (ADC) values (1.12 ± 0.21 vs. 1.73 ± 0.27 × 10-3 mm2/s, p < 0.01) of solid components was significantly lower in LGSCs than in SBTs. CONCLUSION: Compared with SBTs, lower signal intensity on T2-weighted images and lower ADC values were characteristic features of solid components in LGSCs. Papillary growth pattern with internal branching was not observed in LGSCs.