Histopathologic characteristics of uveal melanomas in eyes enucleated from the Collaborative Ocular Melanoma Study. COMS report no. 6

Altered expression of Rb and p53 in uveal melanomas following plaque radiotherapy

PURPOSE

To examine the expression of proteins in the Rb and p53 tumor suppressor pathways in uveal melanomas following plaque radiotherapy.

METHODS

Immunohistochemistry and cell culture studies. Immunohistochemistry for Rb, p16, cyclin D1, p53, HDM2, and Bcl-2 was performed on twelve eyes containing posterior uveal melanomas that were enucleated following plaque radiotherapy. Cell culture studies were performed in three cases.

RESULTS

The irradiated eyes were enucleated for radiation complications (five cases), local tumor recurrence (three cases), and other reasons (four cases). On histopathologic examination, all cases showed evidence of tumor cell loss. However, residual tumor cells were present in all cases, including those that were clinically regressed. Residual cells from three of the clinically regressed cases were cultured and demonstrated minimal cell division, marked cell death, and extensive chromosomal damage. Strong p53 staining was observed in six cases (50%) and was significantly associated with recent radiotherapy (P = .04). Abnormal cytoplasmic staining for Rb was observed in four cases (33%).

CONCLUSIONS

Plaque radiotherapy of uveal melanomas induces DNA damage, inhibits cell division, and promotes cell death. These changes may be due, at least in part, to induction of p53, which activates genes involved in both cell cycle arrest and apoptosis. Plaque radiotherapy can also cause alterations in the expression of Rb, but the significance of this finding will require further study.

Corneal autofluorescence in choroidal melanoma or in choroidal naevus

AIMS

To investigate whether corneal autofluorescence is different in patients with choroidal melanoma or choroidal naevus.

METHODS

Corneal autofluorescence was determined by fluorophotometry in both eyes of 32 patients with a unilateral choroidal melanoma, 32 patients with a unilateral choroidal naevus, and 32 age matched healthy controls. The corneal autofluorescence ratio between affected and contralateral eyes of patients or between randomly selected eyes of healthy controls was calculated.

RESULTS

Mean corneal autofluorescence ratio of patients with a choroidal melanoma was significantly higher than that of healthy controls (mean ratio: 1.09 (SD 0.15) and 1.00 (0.09), respectively, ANOVA p=0.014), and than that of patients with choroidal naevus (mean ratio 0.96 (0.09), p<0.001). Mean ratios of patients with choroidal naevus and healthy controls were not significantly different (p=0.27).

CONCLUSIONS

Corneal autofluorescence ratio of patients with a unilateral choroidal melanoma is increased. This is probably due to an increased flow of glucose through the impaired blood-aqueous barrier in the affected eye, resulting in additional glycation of corneal proteins and hence in increased autofluorescence. The corneal autofluorescence is not increased in patients with a choroidal naevus, because the blood-aqueous barrier is not impaired in the affected eye in these patients. Measurement of corneal autofluorescence is simple, fast, and non-invasive, and might be helpful to distinguish between patients with choroidal melanoma and those with choroidal naevus.

Amelanotic choroidal nevus and melanoma: cytology, tumor size, and pigmentation as prognostic indicators

BACKGROUND

Choroidal nevi are fairly common lesions of the posterior pole that can sometimes transform into melanoma, and it is thought that most choroidal melanomas arise from preexisting nevi. Occasionally, these lesions present as nonpigmented or amelanotic variations of their pigmented counterparts. Recent studies suggest a relationship between tumor pigmentation and risk of growth and metastasis, with a better prognosis for lightly pigmented or amelanotic lesions.

CASE REPORTS

A case of an amelanotic choroidal nevus and melanoma are presented. In Case 1, a 26-year-old white female was found to have a large amelanotic nevus in the right eye. After 7 years of periodic observation, the lesion has not changed. In Case 2, a 51-year-old white male was diagnosed with a large amelanotic melanoma in the left eye. Due to extensive involvement of the optic nerve, the patient underwent enucleation. Histological evaluation confirmed the lesion as a mixed-cell type malignant amelanotic melanoma.

CONCLUSION

Management of choroidal nevi generally consists of periodic observation, and the most widely accepted management of choroidal melanoma is observation, radiotherapy, and transpupillary thermotherapy or enucleation. The therapeutic modality of choice for melanoma will vary depending on the size, growth, and location of the lesion. In addition, recent studies suggest an association between heavy tumor pigmentation, tumor size, cell type, and risk of metastasis. Although many variables will influence the final treatment option, pigmentation of the lesion should also be considered.

Absence of type I estrogen receptors in choroidal melanoma: analysis of Collaborative Ocular Melanoma Study (COMS) eyes

PURPOSE

To evaluate choroidal melanomas in enucleated eyes for the presence of type I estrogen receptors.

METHODS

Fourteen consecutive eyes with large choroidal melanomas (defined as >16-mm basal diameter and >8 mm thickness) from 14 patients (eight women and six men with a mean age of 57 years; range, 25--74 years) enucleated in accordance with the Collaborative Ocular Melanoma Study (COMS) protocol were investigated. Immunohistochemical techniques were employed to label the choroidal melanomas for the presence of type I estrogen receptors. Each specimen was then evaluated in a masked fashion by an experienced ophthalmic pathologist for positive nuclear staining.

RESULTS

No tumors showed immunohistochemical evidence of a type I estrogen receptor.

CONCLUSION

Type I estrogen receptors are not present in choroidal melanoma. Estrogens are not likely to influence choroidal melanoma growth through traditional receptors.

Prognostic factors in uveal melanoma

Uveal melanoma is the most common primary intraocular malignant tumour, with an annual incidence of approximately six cases per million per year. Approximately 40% of patients with posterior uveal melanoma develop metastatic melanoma to the liver within 10 years after initial diagnosis. Despite high accuracy of diagnosis and availability of various methods of treatment; the mortality due to uveal melanoma has remained unchanged. The prognosis in uveal melanoma depends on clinical, histopathological and cytological factors. Clinical factors that relate to prognosis include location, size, and configuration of the tumour. Uveal melanoma can arise in the iris, the ciliary body or the choroid. Iris melanomas have the best prognosis and ciliary body melanomas have the worst prognosis. Based on retrospective studies, the mortality rates for uveal melanoma for comparable sized tumours treated by enucleation or other globe conserving methods such as radiotherapy appear to be similar. Histopathological factors such as cell type, mitotic activity, microcirculation architecture, tumour-infiltrating lymphocytes and the presence of extrascleral extension are also significant predictors of survival. More recently, cytological factors such as cell proliferation, cytogenic, and molecular genetic prognostic markers have been identified with the hope of detecting high risk cases for adjuvant systemic immune therapy or chemotherapy. At present, the role of these therapeutic methods is not clearly established.

Simultaneous choroidal melanoma and rhegmatogenous retinal detachment

A case is reported of a 30-year-old man who presented with the unusual combination of a unilateral inferonasal choroidal melanoma and an unassociated rhegmatogenous retinal detachment attributable to a large horseshoe tear in the superotemporal quadrant. Over 20 cases of simultaneous occurrence of these two phenomena have now been reported but this patient appears to be the youngest. The reports of this uncommon association are reviewed.

nm23 Expression in choroidal melanoma

nm23 protein expression of choroidal melanoma was investigated to determine its relationship with clinical and histopathological characteristics of the tumour. Thirty-four consecutive choroidal melanoma patients were examined by immunohistochemistry. Although age, sex, tumour cell type, tumour size, pigmentation, necrosis, apoptosis and tumour lymphocytic infiltration were not correlated with nm23 protein expression, tumours with low percentages of nm23-positive cells revealed higher nuclear grades and predominant mitotic figures. nm23 may be associated with melanoma progression, but there is no proof that it plays a role in the metabolic process of the tumour.

Plaque radiotherapy for management of ciliary body and choroidal melanoma with extraocular extension

PURPOSE

To report the results of plaque radiotherapy of ciliary body and choroidal melanoma with extraocular extension.

METHODS

This retrospective study of 17 eyes of 17 patients with ciliary body and choroidal melanoma demonstrated extraocular extension that was clinically evident but less than 3 mm in thickness. In 14 eyes, the extraocular extension was located anteriorly and in three posteriorly. The outcome of plaque radiotherapy in terms of intraocular and extraocular tumor responses and the development of metastasis were analyzed.

RESULTS

At a median follow-up of 63 months (range, 23 to 164 months) after plaque radiotherapy, all patients showed control of both the intraocular and extraocular components of ciliary body and choroidal melanoma. In no case did the intraocular or extraocular portion of the tumor relapse. The initial median thickness of the intraocular component was 4.9 mm, and the final median thickness was 2.4 mm. The initial median thickness of the extraocular component was 2.0 mm, and the final median thickness was 1.0 mm. The initial median basal diameter of the extraocular component was 3.5 mm, and the final median basal diameter was 2.0 mm. Of 17 patients, 11 (10 with anterior and one with posterior extraocular extension) showed partial regression in base and thickness of the extraocular extension, and in six there was little or no change. In those with anterior extrascleral extension, the sclera remained intact without clinically observable necrosis, and the scleral fibers were gradually more visible as the tumor regressed. Three patients (18%) died of metastatic melanoma at a median interval of 38 months after plaque radiotherapy.

CONCLUSIONS

Plaque radiotherapy appears to be a reasonable treatment option for selected cases of ciliary body and choroidal melanoma with clinically visible extraocular extension less than 3 mm in thickness.

Intraoperative echographic localization of iodine-125 episcleral plaque for brachytherapy of choroidal melanoma

PURPOSE

To report intraoperative echographic localization of iodine-125 episcleral plaque for brachytherapy of choroidal melanoma.

METHODS

In a retrospective study, 117 eyes with medium-sized choroidal melanoma in 117 patients not participating in the Collaborative Ocular Melanoma Study underwent iodine-125 episcleral plaque radiotherapy with intraoperative echographic verification of plaque placement between January 1992 and December 1998 at the Bascom Palmer Eye Institute.

RESULTS

After initial plaque placement using standard localization techniques, intraoperative echography demonstrated satisfactory tumor-plaque apposition in 76% of eyes (89 of 117). In the 28 eyes (28 of 117, 24%) that required repositioning of the plaque, the extent of misplacement was less than 1 mm in 10 eyes, 1.1 to 3.0 mm in six eyes, and greater than 3 mm in eight eyes. Two eyes had tilting of the plaque, and in two additional eyes, although the plaque covered all tumor margins, the centration was considered suboptimal. Repositioning was necessary in 1 eye with an anteriorly located tumor (1 of 13, 7.7%) and in 20 eyes with peripapillary or posterior pole tumors (20 of 67, 26.3%). Anteriorly located tumors required plaque repositioning significantly less frequently than did posteriorly located tumors (P = .041). Misalignment involved one tumor margin in 23 eyes and two margins in five eyes. The most commonly misaligned margins were the lateral (35%) and posterior margins (26%). In no case was an anterior marginal misalignment documented. At a mean follow-up of 37 months, no tumor-related death or metastatic disease was noted. Two of the 117 patients (1.7%) had local tumor recurrence and underwent enucleation.

CONCLUSIONS

Intraoperative echography is an effective adjunct for localization and confirmation of tumor-plaque relationship. This technique facilitates the identification and correction of suboptimal plaque placement at the time of surgery, potentially minimizing treatment failures.

Enucleation

The three most common indications for enucleation are intraocular malignancy, trauma, and a blind, painful eye. Recommending enucleation is one of the most difficult therapeutic decisions in ophthalmology. In some cases of malignancy, cryotherapy, laser photocoagulation, diathermy, chemotherapy, and radiation therapy may be viable alternatives to surgery. When surgery is chosen, evisceration or exenteration may be alternatives to enucleation. Once the decision is made to perform enucleation or evisceration, the surgeon must choose from several types of implants and wrapping materials. These devices can be synthetic, autologous, or eye-banked tissues. With certain implants, the surgeon must decide when and if to drill for subsequent peg placement. In this review, the authors discuss choices, techniques, complications, and patient consent and follow-up before, during, and after enucleation. Controversies and results of the Controlled Ocular Melanoma Study are summarized.

Extraocular extension of unrecognized choroidal melanoma simulating a primary optic nerve tumor: report of two cases

BACKGROUND

Orbital extraocular extension of choroidal melanoma is well known and is usually detected in eyes with medium and large tumors, but it is very rare with small melanomas. It is particularly unusual for choroidal melanomas of any size to invade the optic nerve or its meninges.

DESIGN

Two case reports.

PARTICIPANTS

Two patients with small, relatively inconspicuous juxtapapillary pigmented choroidal lesions were referred with the diagnosis of primary optic nerve tumor. Both demonstrated a large nodular tumor in the meninges of the optic nerve, immediately posterior to the globe.

METHODS

Retrospective review of clinical records and histopathology.

RESULTS

In both cases, orbital magnetic resonance imaging confirmed the presence of a hyperintense enhancing nodular mass near the anterior portion of the optic nerve, prompting optic nerve biopsy in one case. Subsequent fundus examination disclosed a small juxtapapillary pigmented choroidal lesion measuring 1.0 mm or less in thickness. These observations suggested that the optic nerve tumor might be nodular extraocular extension of a small choroidal melanoma. Modified enucleation was performed in both cases, and histopathologic examination revealed a nodule of malignant melanoma within the meninges that compressed the optic nerve and extended extraocularly from a small, relatively inapparent juxtapapillary choroidal melanoma. In both cases, the extraocular component was large and symptomatic, whereas the intraocular component was inconspicuous.

CONCLUSIONS

Small juxtapapillary choroidal melanomas can exhibit prominent extension into the orbit. All patients with orbital tumors should have careful ophthalmoscopy.

The Collaborative Ocular Melanoma Study (COMS) randomized trial of pre-enucleation radiation of large choroidal melanoma III: local complications and observations following enucleation COMS report no. 11

PURPOSE

To summarize local complications and observations following enucleation of eyes with large choroidal melanoma that were reported prospectively at scheduled examinations of patients enrolled in the Collaborative Ocular Melanoma Study (COMS) randomized trial of pre-enucleation radiation.

METHODS

Of 1,003 patients with large choroidal melanoma who were assigned randomly at time of enrollment to enucleation alone or to pre-enucleation radiation, 994 were treated as assigned. Complications and observations were reported to the Coordinating Center on standard forms completed at the time of enucleation surgery and during the immediate 24-hour postsurgery period, 1 to 6 weeks following surgery, 6 and 12 months after enucleation, and at examinations scheduled at 12-month intervals thereafter.

RESULTS

The most common perioperative complication was pain that prolonged hospital stay, which was reported for six patients (1%) who had standard enucleation and eight patients (2%) who had pre-enucleation radiation. Patients treated with pre-enucleation radiation had somewhat more complications reported at the examination 1 to 6 weeks after surgery than did patients treated with enucleation alone, 36 (8%) and 21 (4%), respectively (P = .03, chi2 test), but all complications were minor. During follow-up, fewer biopsy-confirmed tumor recurrences in the orbit were observed among patients treated with pre-enucleation radiation than with enucleation alone (0 vs 5, respectively; P = .03, Fisher exact test). Patients treated with pre-enucleation radiation also had a lower incidence of severe ptosis than did patients treated with enucleation alone (P = .007, log rank test). Among 307 patients examined 5 years after enucleation, the most frequent complication reported at the 5-year examination was poor prosthetic motility for 24 patients (16%) treated with enucleation alone and 30 patients (19%) treated with pre-enucleation radiation.

CONCLUSIONS

Complications were infrequent during the 5-year period following enucleation surgery. Five-year incidence rates and prevalence at the 5-year examination of most complications were similar in the two treatment arms. There was no indication that pre-enucleation radiation had resulted in more serious complications.

Uveal Melanoma

BACKGROUND: Malignant melanoma of the uveal tract is a rare malignancy but a significant cause of mortality and visual loss. Approximately 50% of patients diagnosed with a melanoma of the choroid or ciliary body will die of the disease within 15 years of enucleation. METHODS: The author reviewed the current literature on the clinical findings, epidemiology, and treatment of uveal melanoma. RESULTS: Methods of diagnosis have improved substantially in the past several years, although clinical diagnosis by an experienced examiner remains the standard in eyes with clear media. Ultrasound is the most useful adjunctive technique. While enucleation has been the mainstay of therapeutic intervention, alternative therapies - especially different types of irradiation - offer hope for tumor control and vision preservation. The Collaborative Ocular Melanoma Study, a multicenter national trial, is designed to provide long-term data on the natural history as well as therapeutic intervention. CONCLUSIONS: Malignant melanoma of the uveal tract can be diagnosed clinically with more confidence than ever before. It is also possible in many cases to retain the eye and functional vision while controlling the tumor. However, unanswered questions remain about the natural history and optimal therapy of uveal melanoma.

The Collaborative Ocular Melanoma Study (COMS) randomized trial of pre-enucleation radiation of large choroidal melanoma II: initial mortality findings. COMS report no. 10

PURPOSE

To report initial mortality findings from the Collaborative Ocular Melanoma Study (COMS) randomized clinical trial of pre-enucleation radiation of large choroidal melanoma.

METHODS

Patients were evaluated for eligibility at one of 43 participating centers in the United States and Canada. Eligible consenting patients were assigned randomly at the time of enrollment to standard enucleation or to external radiation of the orbit and globe prior to enucleation. Eligibility was confirmed at the COMS Coordinating Center, Echography Center, and Photograph Reading Center. Adherence to the radiotherapy protocol was monitored at the Radiological Physics Center. The diagnosis of choroidal melanoma was confirmed following enucleation by a three-member Pathology Review Committee. Patient accrual began in November 1986 and was completed in December 1994; 1,003 patients enrolled. Patients have been followed at annual clinical examinations. Cause of death was coded by a Mortality Coding Committee whose members were not involved in the care of COMS patients; the clinical trial was monitored by an independent Data and Safety Monitoring Committee.

RESULTS

A total of 1,003 patients were enrolled; 506 were assigned to enucleation alone and 497 to pre-enucleation radiation. Treatment groups were well balanced on baseline characteristics. Only nine patients were found to be ineligible after enrollment, seven in the interval between randomization and enucleation and two after enucleation based on histopathology. All but nine patients were treated as assigned; in only six of 491 eyes treated with pre-enucleation radiation was there a major deviation from the radiotherapy protocol. With 5-year outcome known for 801 patients enrolled (80%), the estimated 5-year survival rates and 95% confidence intervals (CIs) were 57% (95% CI, 52% to 62%) for enucleation alone and 62% (95% CI, 57% to 66%) for pre-enucleation radiation. Among the baseline covariates evaluated, only age and longest basal diameter of the melanoma affected the prognosis for survival to a statistically significant degree. The risk of death among patients treated with pre-enucleation radiation relative to those treated with enucleation alone after adjustment for baseline characteristics of patients, eyes, and tumors was 1.03 (95% CI, 0.85 to 1.25). Of 435 deaths classified by the Mortality Coding Committee, 269 patients had histologically confirmed melanoma metastases at the time of death. Estimated 5-year survival rates for this secondary outcome were 72% (95% CI, 68% to 76%) for enucleation alone and 74% (95% CI, 69% to 78%) for pre-enucleation radiation.

CONCLUSIONS

No survival difference attributable to pre-enucleation radiation of large choroidal melanoma, using the COMS fractionation schedule, has been demonstrated to date in this randomized trial. The trial had statistical power of 90% to detect a relative difference in mortality rates between the two treatment arms of 20% or larger. A smaller difference is possible, but a clinically meaningful difference in mortality rates, whether from all causes or from metastatic melanoma, is unlikely.