Ocular malignant melanoma and blue nevi.

Abstract

To the Editor: Wieselthier and White recently reported a case in an article entitled: "Cutaneous Metastasis of Ocular Malignant Melanoma" (1). We report a similar case but with different clinical features. In 1992, a woman aged 80 years, diagnosed with choroidal malignant melanoma (MM) 3 weeks earlier, came to us for consultation. She had been referred by the ophthalmologic department for evaluation of multiple, black-bluish papules localized in the right frontal, temporal, and parietal regions, in a zosteriform distribution, that had first appeared 40 years earlier. She explained that these lesions appeared at the same time that she experienced "volante mouche" in the right eye. The right eye was enucleated. Histopathologic examination showed an MM of the choroides of mixed spindle cell and epithelioid types. As in the patient of Wieselthier and White, results of metastatic workup in our patient, including a complete blood laboratory study, chest and bone roentgenograms, a gammagraphic liver study, and computed tomography scans of head, chest, and abdomen, were normal. Four cutaneous papules were completely excised; all of them showed an identical histologic pattern of blue nevus. Clinically, our patient was diagnosed with ocular MM occurring in the setting of an agminated-type blue nevus. Agminated-type blue nevus is also termed multinodular plaque-type blue nevus and eruptive blue nevus. It is usually present at birth, although it has also been observed later, even in the fourth decade of life (2). Although we have not found in the literature a report of the occurrence of malignancy associated with agminated-type blue nevus, malignancy related to oculodermal melanocytosis (cellular blue nevus and nevus of Ota) has been reported (3). Figures 1 and 4FIG. 1: Clinical appearance of multiple blue nevi, localized in the right frontal and temporal regions.Oculodermal melanocytosis has been associated with choroid MM as well as with skin, orbita, and central nervous system MM (3). Indeed, ocular and oculodermal melanocytosis are more common in patients with choroid MM than in the general population (4). Our case differs from that of Wieselthier and White in that blue nevus lesions were present for >40 years before the diagnosis of ocular MM was made, a period of time much longer than the mean survival time reported by Wieselthier and White for their patient. Furthermore, in repeated cutaneous histopathologic studies, they were unable to detect histologic signs of malignancy. Figures 2 and 3FIG. 2: Ocular malignant melanoma.FIG. 3: Light microscopy of one of the cutaneous biopsies. Clumps of melanin-laden spindle cells distributed in midreticular dermis.Therefore, we believe that ocular MM can provoke cutaneous metastasis that clinically and histologically are similar to blue nevus, but we also believe that malignant changes could occur in the setting of an oculodermal melanocytosis of blue nevi type. Our case was previously reported in the International Dermatology Journals of Barcelona, Spain. (Barcelona, October 22-23, 1993). M. T. Lopez M. M. Alsina J. M. Mascaró Dermatology Department C/ Casanova, 143; Barcelona, Spain