Visual loss and enlarged extraocular muscles from metastatic signet ring carcinoma

Abstract

Sirs: Metastases of solid tumours to the orbit occur much less frequently than to the eye, with an incidence between 2–7 %, and the involvement of the ocular striated muscles is typically related to the extension of a contiguous neoplasm [1, 13]. Solitary metastases to extraocular muscles without changes in other orbital structures is uncommon [2, 4], although skeletal muscle elsewhere may be a site for secondary growth of solid tumours [5, 8, 14, 15]. When skeletal muscle metastases are the initial presentation of a neoplasm, the diagnosis is usually that of soft-tissue sarcoma [9]. A 49-year-old woman who had smoked 20 cigarettes daily since the age of 18 years, developed a progressive, painless visual loss leading to amaurosis in the right eye in 1 month, while her left eye was normal. Her medical history included a transient (2-week) episode of vision loss in the left eye at the age of 10 years. Before hospitalization in our department she underwent intravenous therapy with high doses of methylprednisolone (1 g for 3 days) without modification of the clinical picture. Neurological examination showed visual loss in the right eye with a restriction of lateral and upward movements of the same eye. She had bilateral exophthalmos, more evident in the right eye, and the funduscopy examination was normal. No other pathological features were detected except for three subcutaneous nodes in the trunk without lymphadenopathy. Routine laboratory examinations were normal except for a high erythrocyte sedimentation rate (82 mm/h). The tumour markers, cancer antigen 15–3, carcinoembryonic antigen and cancer antigen 19–9 were increased. Orbital computed tomography showed pathological swelling of the right multiple ocular muscles with dislocation of the optic nerve. Magnetic resonance orbital imaging after injection of paramagnetic contrast (Fig. 1) revealed infiltrative processes with inhomogeneous enhancement in the right medial rectus, right lateral rectus and left medial rectus muscles. A lumbar puncture revealed normal cerebrospinal fluid. The biopsy specimen from one of the trunk subcutaneous nodes showed infiltration of fibroadipose and muscular tissue by adenocarcinoma (Fig. 2). At this time the research for the primary neoplasm was undertaken and, after a negative mammography, gastroscopy examination yielded evidence of multiple ulcerations, biopsy of which revealed a signet ring carcinoma. Other examinations, such as chest radiography, LETTER TO THE EDITORS