Bilateral multiple extraocular muscle metastasis from hepatocellular carcinoma
A 44-year-old man presenting with diplopia of three months' duration was admitted to our hospital in August 2011. A detailed history revealed that he had undergone partial resection for HCC in the S7 segment in March 2010.\nThree months before his visit to us, he developed rapidly progressive proptosis and double vision. In addition, he reported a 7-kg weight loss within the past month. Ophthalmologic examination disclosed that his visual acuity was normal in both eyes with normal anterior and posterior segments. Motility examination of the right eye revealed severe limitation of adduction and depression, and moderate limitation of elevation and abduction. The left eye revealed severe limitation of adduction and abduction.\nOrbital MRI showed nodular enlargement of the bilateral multiple EOMs, including the right superior oblique muscle, lateral rectus and inferior rectus, and the left lateral and medial rectus. The enlarged EOMs exhibited isointensity to cerebral white matter on T1-weighted images (Fig. ) and heterogeneous intermediate-to-high signal intensity to cerebral white matter on T2-weighted images (Fig. ). The muscle borders were well-defined, and there was mild-to-significant heterogeneous contrast enhancement with gadolinium (Fig. ). The tendons were seen to be spared, and there was no evidence of orbital bone marrow involvement. Orbital echography revealed multiple enlarged EOMs with low internal reflectivity.\nBiopsy of the right superior oblique muscle was performed by a lid crease incision. Microscopic examination revealed a diffuse infiltration of atypical polygonal cells, which contained hyperchromatic nuclei in the eosinophilic cytoplasm. Immunohistochemically, the tumor cells were positively stained for AFP (Fig. ). These features were consistent with metastatic HCC with moderate differentiation. The patient received external beam radiation therapy to the orbit, which led to significant improvement of his bilateral proptosis and ocular motility.