Iris metastasis from a bronchial carcinoid tumor

A 54-year-old man had a fleshy pink vascularized mass in the superonasal quadrant of the right iris. He had a history of an unchanging pulmonary nodule that was followed up for five years with routine chest roentgenograms. Fluorescein angiography demonstrated early filling of numerous fine blood vessels in the mass and diffuse late staining of the lesion. Results of a transcorneal radioactive phosphorus (32P) uptake test were positive. The clinical diagnosis was tapioca melanoma of the iris, with metastatic tumor as a second possibility. The tumor was excised by iridocyclectomy. Light microscopy revealed nests of tumor cells with oval hyperchromatic nuclei. Fontana stains for melanin were negative as were argentaffin and argyrophil strans. Electron microscopy demonstrated light and dark tumor cells containing numerous membrane-bound electron-dense neurosecretory granules. The diagnosis was iris metastasis from a probable bronchial carcinoid. The patient is alive and well years after excision of the iris mass.