In the present timeframe of our update review (1988 to 1997), we have not encountered a primary orbital malignant melanoma. Probably, the most informative publication in this period is that of Tellada et al. (1996). They studied 21 cases from the file at the Armed Forces Institute of Pathology. The mean age at diagnosis was 42 years (range 15 to 84 years). There was an associated intraorbital blue nevus (see Figs. 12.1 and 12.2) in 19 patients (90%), and in 10 patients (47.5%) there was some form of congenital melanosis. All patients were of the white race. The male-to-female ratio was approximately 3:1 (16 men, 5 women). Histopathologically, 11 (52%) tumors were of the mixed cell type and 10 (48%) were spindle cell tumors. Risk factors for poor prognosis in their series were associated with mixed cell type histology and high mitotic content. They conclude that primary orbital melanomas are similar to uveal melanomas with respect to prognostic indicators.

Single case reports in the literature during the current period are: Loffler and Witschel (1989) (M 27); Rice and Brown (1990) (F 17); Shields et al. (1993) (M 70); Ijiri et al. 2000 (F 5). Two tumors of the above group originated from a cellular blue nevus. The other two were thought to be de novo. In none of the four cases was there any accessory pigmentation in the orbital soft tissues. Histologically, two tumors were of the spindle cell type; one was a mixed epithelioid–spindle cell tumor, and one was predominantly epithelioid type. At the time of presentation, two of these cases were thought to have an orbital vascular tumor. In one of the latter, the orbital mass had the imaging characteristics of a varix. In the 5-year-old child, repeated episodes of subconjunctival hemorrhage were noted.

In the third edition of this text, and as noted in the preceding text, we listed 23 patients with an orbital extension from an intraocular malignant melanoma. We tabulated the age, sex, treatment, and follow-up of these patients over the 40-year period from 1948 to 1987. In all but three of these cases, an enucleation or evisceration of one eye had previously been performed. Such patients were aware their eye contained either a tumor or a malignant melanoma. In these cases, the suspicions of both patient and physician for recurrent tumor were confirmed. Most of these patients sought consultation because of the need for frequent adjustments of their prosthesis over a period of several months. An occasional patient also noted some discoloration of his/her eye socket. Rarely, the initial manifestation of orbital recurrence was associated with swelling of the eyelids and orbital pain, a likely indication of hemorrhage or necrosis within the neoplasm. In all these patients, an orbital mass other than an orbital implant was palpable. The age range of these patients was 16 to 84 years; the average age was 60.6, and the follow-up range

was 3 months to 20 years. The sex ratio was 12 women and 11 men. We now add six cases to this group of secondary melanomas seen in the last decade (1988 to 1997) of our 50-year statistical survey. These included two men, ages 50 and 65, and four women, ages 74, 75, 81, and 85. Follow-up time for this group of six patients was too short to make any statement concerning the effect of treatment on prognosis.