case_images: PMC5465689_01
case_images: Endoscopic view of the left ear. Not only reddened and swelling tympanic membrane, but also a partial defect of the posterior ear canal wall can be observed.
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case_images: Ear endoscopy revealed a reddened region around the posterior-superior ear canal (Fig. 1), but no mucosal otorrhea or perforation of the tympanic membrane or posterior canal wall was observed.
case_images: a Preoperative coronal CT scan shows a large jugular bulb on the right, and the facial nerve (arrowhead) and a boundary to the facial nerve in the mastoid segment is obscure. Similar findings are also indicated in the axial view (arrow). Tumor invasion to the facial nerve could not be conclusive and distinguish from cholesteatoma recurrence and viral infection through this image. b Postoperative MR image showing a mass occupying the jugular bulb on the right (arrowhead) and its continuity extend to the sigmoid sinus (arrow).
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case_images: High-resolution CT revealed an intratympanic and mastoid mass involving the facial nerve in the mastoid and tympanic segments (Fig. 2a). Otalgia and retro-auricular pain were relieved for a few days after surgery, but severe pain recurred, and postoperative MRI showed a mass occupying the sigmoid sinus, indicating hematogenous metastasis (Fig. 2b).
case_images: Photomicrograph of the biopsy specimen shows large neoplastic cells with clear cell type-cytoplasm (arrow), which suggests metastasis of RCC (HE stain, x200). RCC, renal cell carcinoma.
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case_images: A biopsy specimen was obtained from around the mastoid segment of the facial nerve, and histologic appearance of the specimen demonstrated patterns of clear cell type-RCC compatible with metastasis of the original tumor (Fig. 3).