MRI for differentiating primary fallopian tube carcinoma from epithelial ovarian cancer.

PURPOSE: To compare potential discriminatory magnetic resonance imaging (MRI) features of primary fallopian tube carcinoma (PFTC) and primary epithelial ovarian cancer (EOC). MATERIALS AND METHODS: MRI features (the laterality, shape, size, signal intensity, enhancement of solid portion, amount of ascites, peritoneal planting, lymph nodes, or distant metastasis) of 27 tumors in 23 patients with PFTC confirmed by surgery and pathology were compared with 42 tumors in 37 patients with EOC. RESULTS: The mean maximum diameter was 6.1 ± 0.7 cm in PFTC versus 10.2 ± 0.6 cm in EOC. MRI features of PFTC were sausage-like shape (19/27, 70%), or irregular (8/27, 30%) shape; solid (20/27, 74%) or cystic-solid (7/27, 26%) mass; homogeneous (21/27, 78%) or heterogeneous (6/27, 22%) signal on T2 -weighted images; mild (8/27, 30%), moderate (13/27, 48%), or prominent (6/27, 22%) enhancement; associated hydrosalpinx (13/27, 48%) or intrauterine fluid accumulation (7/23, 30%). Significant differences between PFTC and EOC were found in the size, shape, configuration, signal homogeneity, and enhancement pattern, associated hydrosalpinx, and intrauterine fluid accumulation (P < 0.001, < 0.001, 0.015, 0.001, < 0.001, < 0.001, and 0.001, respectively). CONCLUSION: PFTC often appears as a small-sized solid mass, with a sausage-like shape, homogeneous signal, mild or moderate enhancement, hydrosalpinx, or intrauterine fluid accumulation. Our preliminary study shows that MRI can identify the characteristic features of PFTC and differentiate PFTC from EOC.

MR Spectroscopy for Differentiating Benign From Malignant Solid Adnexal Tumors.

OBJECTIVE: The purpose of this article is to investigate the proton MR spectroscopy ((1)H-MRS) features of solid adnexal tumors and to evaluate the efficacy of (1)H-MRS for differentiating benign from malignant solid adnexal tumors. MATERIALS AND METHODS: Sixty-nine patients with surgically and histologically proven solid adnexal tumors (27 benign and 42 malignant) underwent conventional MRI and (1)H-MRS. Single-voxel spectroscopy was performed using the point-resolved spectroscopy localization technique with a voxel size of 2 × 2 × 2 cm(3). Resonance peak integrals of choline, N-acetyl aspartate (NAA), creatine, lactate, and lipid were analyzed, and the choline-tocreatine, NAA-to-creatine, lactate-to-creatine, and lipid-to-creatine ratios were recorded and compared between benign and malignant tumors. RESULTS: A choline peak was detected in all 69 cases (100%), NAA peak in 67 cases (97%, 25 benign and 42 malignant), lipid peak in 47 cases (17 benign and 30 malignant), and lactate peak in eight cases (four benign and four malignant). The mean (± SD) choline-tocreatine ratio was 5.13 ± 0.6 in benign tumors versus 8.90 ± 0.5 in malignant solid adnexal tumors, a statistically significant difference (p = 0.000). There were no statistically significant differences between benign and malignant tumors in the NAA-to-creatine and lipid-to-creatine ratios (p = 0.263 and 0.120, respectively). When the choline-to-creatine threshold was 7.46 for differentiating between benign and malignant tumors, the sensitivity, specificity, and accuracy were 94.1%, 97.1%, and 91.2%, respectively. CONCLUSION: Our preliminary study shows that the (1)H-MRS patterns of benign and malignant solid adnexal tumors differ. The choline-to-creatine ratio can help clinicians differentiate benign from malignant tumors.

Primary fallopian tube carcinoma: correlation between magnetic resonance and diffuse weighted imaging characteristics and histopathologic findings.

OBJECTIVE: The aim of this study was to investigate the magnetic resonance (MR) and diffusion-weighted (DW) imaging characteristics of primary fallopian tube carcinoma (PFTC). METHODS: The clinical, MR, and DW imaging characteristics and pathologic findings of 23 patients with 27 tumors were studied retrospectively. The MR and DW imaging appearance of tumors including laterality, size and shape, architecture, signal intensity, apparent diffusion coefficient (ADC) value, enhancement pattern, hydrosalpinx, and intrauterine fluid collection were evaluated and correlated with pathologic findings. RESULTS: Histopathologically, all 27 tumors were serous carcinoma with a unilateral tumor in 19 patients and bilateral tumors in 4 patients. Thirteen patients (57%) with PFTC were misdiagnosed preoperatively, 10 of which as epithelial ovarian carcinoma. The mean (SD) largest diameter was 61 (7) mm. The tumor shape was fusiform, sausagelike, or serpentine in 19 patients (70%) and nodular or irregular in 8 patients (30%). Twenty (74%) of the 27 tumors were solid, and 7 (26%) were cystic-solid. The solid components showed hypointensity to isointensity on T1-weighted imaging, and isointensity to slight hyperintensity on T2-weighted imaging. There were obvious hyperintensity on DW imaging; obvious hypointensity on ADC maps with a mean (SD) ADC value of 0.79 (0.22) × 10 mm; and mild (8/27, 30%), moderate (13/27, 48%), and marked (6/27, 22%) enhancement on contrast-enhanced imaging. Ipsilateral hydrosalpinx, intrauterine fluid collection, and ascites were found in 14 tumors (52%) and 7 (30%) and 5 (22%) patients, respectively. CONCLUSIONS: The PFTC has some characteristic MR imaging features. The DW imaging, ADC maps, and ADC values are helpful for the detection and differentiation of PFTC from other pelvic masses.

Magnetic resonance imaging for distinguishing ovarian clear cell carcinoma from high-grade serous carcinoma.

BACKGROUND: To compare the magnetic resonance imaging (MRI) features of ovarian clear cell carcinoma (CCC) and high-grade serous carcinoma (HGSC), to distinguish CCC from HGSC. METHODS: MRI features (laterality, shape, size, configuration, papillary projection, signal intensity, enhancement, peritoneal implant, lymphadenopathy, ascites) of 40 tumors in 37 patients with CCC, confirmed by surgery and pathology, were compared with those of 62 tumors in 40 patients with HGSC. Statistical analysis was performed using Mann-Whitney and Fisher's exact tests. RESULTS: There was a statistically significant difference in the mean maximum diameter, laterality, and FIGO stage (P = 0.002, P < 0.001, P < 0.001, respectively) between CCC and HGSC. Compared to HGSCs, CCCs were more frequently oval (30/40, 75 % vs 12/62, 19 %; P < 0.001), more often cystic (21/40, 53 % vs 8/62, 13 %; P < 0.001) and unilocular (23/29, 79 % vs 7/31, 23 %; P < 0.001), had T1-hyperintense cystic components more often (18/29, 62 % vs 5/29, 17 %; P < 0.001), had larger papillary projections (5.13 ± 0.4 cm vs 2.91 ± 0.3 cm; P < 0.001), were peritoneally implanted less frequently (P = 0.001) and had fewer ascites (P < 0.001). CONCLUSIONS: CCC typically showed an oval, unilocular cystic mass with large papillary projection and T1-hyperintense cystic components. MRI could be helpful for distinguishing CCC from HGSC.