Abstract
Background Ovarian cancer is a common gynecological malignancy and often diagnosed late with extensive peritoneal and nodal metastasis. Diffusion-weighted imaging (DWI) provides valuable information about the structural properties of the tissue and has shown great value in cancer imaging. Recently developed post-processing three-dimensional apparent diffusion coefficient (3D ADC) map has a significant value in variable tumors yet its role in ovarian cancer is not well established. We aim to evaluate the added value of DWI and 3D ADC maps in the diagnosis of ovarian masses, detection of nodal and peritoneal deposits, and so appropriate management planning. Results Conventional MRI and DWI were performed to fifty-one patients with complex cystic or solid adnexal lesions depicted by gynecological ultrasonography. Results were compared with surgical and histopathologic findings revealing 23/51 (45%) had malignant ovarian tumors and 28/51 (55%) had benign ovarian pathologies. The mean 3D ADC values were 0.977 +/- 0.32, 0.934 +/- 0.27, and 0.956 +/- 0.25 x 10(-3) mm(2)/s for ovarian, nodal, and peritoneal malignancy respectively which were significantly lower than the mean 3D ADC values of benign ovarian lesions, non-metastatic lymph nodes and benign peritoneal lesions/fat which were measured 1.516 +/- 0.6, 1.208 +/- 0.25, and 1.46 +/- 0.43 x 10(-3) mm(2)/s respectively. Conclusion Adding DWI and 3D ADC maps to routine MRI improves the sensitivity, specificity, and accuracy for detecting ovarian malignancy, nodal, and peritoneal metastasis. They also provide qualitative data helping in the differentiation of malignant and non-malignant entities.