Fig. 5

a A 71-year-old woman with ovarian cancer showing carcinomatous peritonitis and pleural effusion confirming the presence of malignant cells. After NAC, axial T2-weighted PET/MR image shows the omental cake with FDG uptake (arrow). b Contrast-enhanced CT shows the thickened omentum with slight enhancement (arrow). These findings strongly suggested potential residual disease, which was confirmed by histopathologic examination. c A 77-year-old woman with ovarian cancer with carcinomatous peritonitis and ascites confirming the presence of malignant cells. After NAC, axial T2-weighted PET/MR image shows the almost disappear of the omental cake and FDG uptake (arrow). d Contrast-enhanced CT also shows the almost disappear of thickness and enhancement of the omentum (arrow). These findings show the marked response to NAC. However, histopathologic examination confirmed residual disease comprising high-grade serous carcinoma with carcinomatous peritonitis