Malignant transformation of an optic disk melanocytoma

The role of OCT angiography in a rare case of malignant trasformation of an optic disc melanocytoma

The melanocytoma is a benign, highly pigmented tumor, localized on or adjacent to the optic disc. Its malignant trasformation represents a rare event. We describe a case of a 43-years old woman returned to our observation 29 years later with a malignant melanoma from an optic disc melanocytoma evaluated by Optical Coherence Tomography Angiography (OCTA). OCTA is a valid, non-invasive, dyeless and reliable method that could improve the diagnosis of this rare case of malignant trasformation of an optic disc melanocytoma.

Melanocytoma of the optic disk: A review

Melanocytoma is a deeply pigmented variant of melanocytic nevus that classically occurs in the optic disk, sometimes with contiguous involvement of the adjacent retina or choroid. Historically, this tumor was often confused with malignant melanoma both clinically and histopathologically. Today, however, it is generally recognized by its typical clinical features that differ from most melanomas and erroneous enucleation is rarely done. Histopathologically, melanocytoma is composed of intensely pigmented round to oval nevus cells with benign features. Although traditionally believed to be a relatively stationary lesion, it is now known to exhibit minor enlargement in 10--15% of cases and can cause minor visual loss by a variety of mechanisms. In rare instance, it can induce severe visual loss due to spontaneous necrosis of the lesion or compressive optic neuropathy. More importantly, it can exhibit malignant transformation into melanoma in 1--2% of cases. Ophthalmologists should be familiar with melanocytoma of the optic disk and affected patients should be followed periodically.

Solitary neurofibroma of the orbit with intracerebral extension associated with ocular surface melanocytoma: a case report

Solitary or isolated neurofibroma is uncommonly observed in the orbit. Neurofibromas typically involve peripheral nerves and occasionally the cranial nerves. A 29-year-old man presented with recent onset left eye proptosis and exotropia. Physical examination was positive for hyperpigmented lesions of the ipsilateral ocular surface and hard palate. Imaging revealed an infiltrative orbital mass with extension through superior orbital fissure into the brain. There was also bone defect of greater sphenoid wing. Medial orbitotomy was performed to obtain biopsies of the orbital mass and the pigmented ocular surface lesions. Histopathologic diagnosis of neurofibroma was confirmed for the former and melanocytoma for the latter. His symptoms and examinations remained stable during the follow up. This case is unique due to several features, including extensive intracerebral spread of orbital neurofibroma in a patient without definite diagnosis of neurofibromatosis type 1 and association with ipsilateral ocular surface melanocytoma and palatal pigmented lesions.

ABBREVIATIONS

CT: computed tomography; GFAP: glial fibrillary acid protein; MRI: magnetic resonance imaging; NF-1: neurofibromatosis type 1.

MELANOCYTOMA OR JUXTAPAPILLARY MELANOMA?

PURPOSE

To report the case of a melanocytoma of the optic disc leading to severe vision loss, raising concern for possible malignant transformation and optic nerve infiltration.

METHODS

Case report.

RESULTS

A 36-year-old Arabic woman presented to an outside facility with severe vision loss and a clinical picture concerning for optic neuritis with central retinal vein occlusion. On referral to the authors' institution 1 month after initial presentation, the vision of the patient was no light perception in the affected eye, and examination revealed the presence of a pigmented lesion adjacent to the nerve. Although standard 3-T magnetic resonance imaging orbits suggested 15 mm of optic nerve involvement, ultrahigh resolution 7-T magnetic resonance imaging was able to detect only 2 mm of optic nerve involvement.

CONCLUSION

Melanocytoma of the optic disc is most often benign and causes few visual symptoms. However, in rare cases it can lead to severe vision loss and raise concern for malignant transformation. A 7-T magnetic resonance imaging provides higher resolution optic nerve images.

Infrared autofluorescence, short-wave autofluorescence and spectral-domain optical coherence tomography of optic disk melanocytomas

AIM

To investigate the findings of infrared fundus autofluorescence (IR-AF) and spectral-domain optical coherence tomography (SD-OCT) in eyes with optic disc melanocytoma (ODM).

METHODS

IR-AF findings and those of other ophthalmologic imaging examinations, including short-wave autofluorescence (SW-AF), fluorescein angiography (FA), fundus color photography, and SD-OCT of 8 eyes of 8 consecutive cases with ODM were assessed.

RESULTS

The ODMs in all cases (100%) presented similar IR-AF, SW-AF, and FA findings. On IR-AF images, ODMs showed outstanding hyper-AF with well-defined outline. On SW-AF images, the area of ODMs presented as hypo-AF. FA images revealed the leaking retinal telangiectasia on the surface of the ODMs. On SD-OCT images in 8 cases (100%), the ODMs were sloped with highly reflective surface, which were disorganized retina and optic nerve layers. In 7 cases (87.5%), peripapillary choroids were involved. The melanocytomas of 8 cases (100%) presented as optically empty spaces. Vitreous seeds were found in one case (12.5%).

CONCLUSION

IR-AF imaging may provide a new modality to evaluate the pathologic features of ODMs, and together with SW-AF imaging, offers a new tool to study biological characteristics associated with ODMs. SD-OCT is a valuable tool in delimitating the tumor extension and providing morphological information about the adjacent retinal tissue.

Malignant Transformation of Optic Nerve Melanocytoma into Melanoma Associated with Ocular Ischemic Syndrome and Oculocardiac Reflex: Case Report and Review of the Literature

PURPOSE

To describe the clinical and pathological features of malignant transformation of an optic nerve melanocytoma over 25 years, associated with spontaneous extensive tumor necrosis, neovascular glaucoma, ocular ischemic syndrome, and oculocardiac reflex.

PROCEDURES

A 60-year-old Caucasian female presented with acute severe left ocular pain and glaucoma with an intraocular pressure of 80 mmHg and bradycardia (28-40 beats/min).

RESULTS

Histopathological examination of the enucleated eye showed features of malignant transformation of a spontaneously necrotic optic nerve melanocytoma associated with ocular ischemic syndrome and neovascular glaucoma.

CONCLUSIONS

Yearly follow-up and awareness of possible but well-documented malignant transformation, even over several decades, is recommended. This case presents malignant transformation of an optic nerve melanocytoma associated with the common complications described in the literature over the years. Of particular interest was the development of oculocardiac reflex in this patient.

Clinical findings and genetic expression profiling of three pigmented lesions of the optic nerve

Background. Optic disk melanocytoma is a primary tumor of the optic disk that represents a clinical diagnostic challenge due to its similarities with melanoma. Purpose. The authors present three cases in which genetic expression profiling was used to identify tumor prognosis of optic disk melanocytoma. Case Series. In two cases fine-needle aspiration biopsy was performed to obtain tissue through a transvitreal route into the apex of the tumor while the patient underwent pars plana vitrectomy, laser ablation, phacoemulsification with posterior chamber intraocular lens implantation, and intravitreal triamcinolone acetonide. In the other case the tissue was obtained after definite enucleation. Conclusion. Genetic expression profiling is a useful diagnostic tool for classification and can provide vital information to the ocular oncologist regarding prognosis.

Bevacizumab for the treatment of a complicated posterior melanocytoma

PURPOSE

To present a case of a complicated posterior melanocytoma that was successfully treated with intravitreal bevacizumab.

CASE REPORT

A 50-year-old Caucasian man was referred with sudden-onset metamorphopsia and decreased vision in his right eye over the course of the last 2 months. His best-corrected visual acuity was 20/80 and poorer than Jaeger 14 in the right eye, and 20/20 and Jaeger 1 in his left eye. In the right fundus, there was a melanocytic lesion occupying the inferotemporal quadrant of the optic disk, extending to the adjacent choroid inferiorly; optic nerve edema, superotemporal retinal vein dilatation, and subretinal fluid under the macula and nasal half of the posterior pole were observed, and a subretinal choroidal neovascularization complex was observed adjacent to the superotemporal margin of the optic disk, confirmed by fluorescein angiography, surrounded by a dense subretinal hemorrhage. Optical coherence tomography showed retinal edema and detachment of neurosensory retina. The patient was treated with three consecutive doses on a monthly basis of intravitreal 1.25 mg/0.05 mL bevacizumab. Visual acuity recovered rapidly, and at 4 months after treatment, it was 20/20 and Jaeger 1, with complete resolution of macular edema and subretinal fluid and hemorrhage. After 3 years of follow-up, best-corrected visual acuity remained stable, macular area was normal, and there was no evident optic nerve edema, retinal vein caliber and aspect were normal, and there was no significant change of the tumor. Fluorescein angiography only evidenced late staining of choroidal neovascularization scar, and optical coherence tomography showed a normal macular anatomy.

CONCLUSION

Intravitreal bevacizumab was effective in the treatment of choroidal neovascularization, optic nerve edema, venous dilatation, and local capillary telangiectasia, complicating an optic disk melanocytoma.

Orbital melanocytoma completely resected with conservative surgery in association with ipsilateral nevus of Ota: report of a case and review of the literature

BACKGROUND

Melanocytomas are rare pigmented primary lesions of the central nervous system arising from melanocytes of leptomeninges. They occur most frequently in the posterior fossa, Meckel's cave, or along the cervical and thoracic spinal cord. Orbital melanocytomas have been rarely reported. Nevus of Ota is a melanocytic lesion that can be associated with cutaneous and meningeal melanocytic neoplasms.

METHODS AND RESULTS

We describe a case of an orbital melanocytoma associated with ipsilateral Nevus of Ota. A 28-year-old man presented with proptosis and an ipsilateral congenital facial melanocytic lesion (Nevus of Ota). After imaging evaluation, a retro-orbital mass was discovered. A needle biopsy was performed and the diagnosis of melanocytoma rendered. The patient underwent complete surgical excision of the lesion.

CONCLUSION

In order to make the correct diagnosis and to choose the appropriate therapy, it is important to be aware of this rare presentation and its association with Nevus of Ota.

[Clinical and paraclinical course of melanocytoma of the optic disk. Contribution of spectral- and time-domain OCT in the study of 10 patients]

INTRODUCTION

Melanocytoma of the optic disk is a rare, benign, slow-growing tumor. We analyzed the clinical and paraclinical features of melanocytomas followed at the Fort-de-France University Hospital to expose and compare characteristics from new clinical imaging.

PATIENTS AND METHOD

This was a prospective study of 10 patients with a melanocytoma of the optic disk. The principal features studied were the ophthalmoscopic findings, the visual field defects, fluorescein angiography features, and the comparison between standard time-domain optical coherence tomography (OCT) characteristics and the latest spectral-domain OCT findings.

RESULTS

The mean age of the patients at diagnosis was 49.2 years. All the patients were from the French West Indies. The lesion was discovered incidentally in 90% of the cases. Visual acuity was normal in 70% of the cases. Visual field defects were present at the first visit in 80% of the cases. Tumor growth was monitored in 50% of the cases during a mean follow up of 4.8 years. The in-depth extension into chorioretina and laterally into the retina were better visualized in spectral-domain OCT than in time-domain OCT as hyperreflective granular dots.

CONCLUSION

Optic disk melanocytoma appears to be a singular benign tumor that is seen more frequently in dark-skinned patients. Most melanocytomas do not cause significant visual impairment but can show substantial growth in size for many years of follow-up. A malignant transformation is always to fear in case of atypical development. Spectral domain OCT seems to be an important tool in the assessment of extension and follow-up.

Malignant transformation of intramedullary melanocytoma: case report

OBJECTIVE

Meningeal melanocytomas are low-grade primary melanocytic tumors with benign histological features and a favorable clinical prognosis. Transition from meningeal melanocytoma to primary melanoma of the central nervous system is exceptionally rare, with only 5 cases having been previously reported. Here, we discuss a case of malignant transformation of an intramedullary melanocytoma to primary melanoma and review the pertinent literature.

CLINICAL PRESENTATION

A 79-year-old woman presented with progressive paresis in the lower limbs followed by sphincter dysfunction. Magnetic resonance imaging scans disclosed an intramedullary lesion located at the T10-T11 level.

INTERVENTION

The patient underwent subtotal resection of an intermediate-grade melanocytoma. Two years later, the tumor recurred locally, and the patient underwent additional surgery to remove the intramedullary mass. The histological findings of the tumor were consistent with an intramedullary malignant melanoma.

CONCLUSION

The malignant transformation of melanocytic tumors of the central nervous system may occur years after surgical treatment, and its incidence remains unknown. Emphasis should be placed on the importance of careful and continued follow-up monitoring of the tumor.

Characteristics of optic disc melanocytomas presenting with visual dysfunction

OBJECTIVE AND DESIGN

A retrospective review study was designed to describe five cases of optic disc melanocytomas with tumor-related visual impairment.

PARTICIPANTS

Five patients with optic disc melanocytoma presented with visual complaints to a tertiary eye hospital in Saudi Arabia.

MATERIALS AND METHODS

Demographic and clinical data were analyzed, including the results of ocular examination, lesion laterality, best-corrected Snellen visual acuity, pupillary reflex, visual field testing, color fundus photography, fundus fluorescein angiography, and ophthalmic ultrasound.

RESULTS

Visual dysfunction secondary to optic disc melanocytoma was identified. Case 1 had macular star edema with mild tumor enlargement, Case 2 had optic atrophy, Case 3 had juxtapapillary choroidal neovascular membrane with macular involvement, Case 4 had optic disc swelling with an enlarged blind spot, and Case 5 had a large altitudinal visual field defect.

CONCLUSION

Although melanocytomas of the optic disc tend to have a benign behavior with slow evolution and stable vision, they may adversely affect visual function through a variety of mechanisms.

[The other pigmented lesions]

Not all intraocular pigmented lesions are melanomas or nevi. In this article, we present what we classically consider to be the main pigmented stains other than melanomas and nevi and their possible forms of treatment. Regarding tumor-related stains, we describe melanocytomas, congenital hypertrophy or reactive hyperplasia of the retinal pigment epithelium, combined hamartoma of the retina and retinal pigment epithelium, and acquired vascular pseudotumors. Among the hemorrhage-related stains, we present pseudotumoral age-related macular degeneration, peripheral exudative and hemorrhagic chorioretinopathy, choroidal hematoma, and rupture of macroaneurysms.

Primary malignant melanoma of the optic nerve sheath: a case report

BACKGROUND

Primary malignant melanoma of the optic nerve or its sheath, without choroidal involvement, is rare.

CASE DESCRIPTION

A case of primary malignant melanoma of the optic nerve in a 67-year-old man is presented.

CONCLUSIONS

With a preserved vision, normal fundoscopy makes the correct preoperative diagnosis a real challenge. Proptosis, as a sole presentation of this lesion, has not been described earlier. Microsurgical excision of such a lesion from the optic nerve saves vision and may be considered a satisfactory management option in selected cases.

Case reports of three patients showing optic nerve head melanocytoma and systemic hypertension

PURPOSE

To report the association of optic disk melanocytoma with systemic hypertension.

CASES

Ocular examination of 3 asymptomatic hypertensive patients revealed a pigmented lesion over the optic disk. After clinical examination and radiological evaluation a diagnosis of optic disk melanocytoma was made. One patient had a mild decrease in visual acuity associated with an increase in size of the lesion during the follow-up. Systemic evaluation revealed increased urinary vanillylmandelic acid in all the patients. MRI showed diffuse adrenal hyperplasia while a (131)I-MIBG scan showed increased uptake in 1 case.

CONCLUSIONS

Optic disk melanocytoma is a benign tumor though the lesion may increase in size with the resultant decrease in visual acuity over few years. It may be associated with systemic hypertension secondary to increased levels of catecholamines in the body, which is related to the common neural crest origin of melanocytes, adrenal medullary cells and chromaffin cells.

Melanocytoma of the optic disk: a review

Melanocytoma is a deeply pigmented variant of melanocytic nevus that classically occurs in the optic disk, sometimes with contiguous involvement of the adjacent retina or choroid. Historically, this tumor was often confused with malignant melanoma both clinically and histopathologically. Today, however, it is generally recognized by its typical clinical features that differ from most melanomas and erroneous enucleation is rarely done. Histopathologically, melanocytoma is composed of intensely pigmented round to oval nevus cells with benign features. Although traditionally believed to be a relatively stationary lesion, it is now known to exhibit minor enlargement in 10-15% of cases and can cause minor visual loss by a variety of mechanisms. In rare instance, it can induce severe visual loss due to spontaneous necrosis of the lesion or compressive optic neuropathy. More importantly, it can exhibit malignant transformation into melanoma in 1-2% of cases. Ophthalmologists should be familiar with melanocytoma of the optic disk and affected patients should be followed periodically.

Mélanocytome de la papille : à propos de trois observations

PURPOSE

Melanocytoma is a rare benign tumor that usually occurs as a pigmented lesion in the optic nerve head. It seems to be more frequently encountered in the Black population. We report three cases of melanocytoma observed in Martinique, where 90% of the population is of African origin.

OBSERVATIONS

The first and second cases were found on routine ophthalmic examination. These patients had a heavily pigmented lesion that obscured part or all of the optic disc with slight extension into the adjacent nerve fiber layer of the retina. The tumor's margins were finely fibrillated. Fluorescein angiography demonstrated a homogenous hypofluorescent black tumor obscuring the optic disc vessels, with no tumor vessels visible. There were no juxtapapillary choroid vascular abnormalities. The third case was discovered on visual field examination. This melanocytoma was accompanied by papillary edema.

CONCLUSION

Only three cases of melanocytoma have been noted from 1994 to 2004 in 150,000 Caribbean patients examined in the University Hospital Center of Fort de France. The rarity of melanoma and the predisposition to melanocytoma are important epidemiologic factors in the etiologic search for pigmented tumor within the Black population. Yearly fundus examination is useful for monitoring growth and detecting malignant transformation.

The optic nerve: radiologic, clinical, and pathologic evaluation

The radiologic investigation of the optic nerve plays an integral part in the diagnostic evaluation of diverse lesions of the optic pathways including inflammatory diseases, vascular disorders and benign and malignant tumors and these radiologic modalities consist principally of CT and MR imaging and, in vascular lesions, MR angiography and conventional angiography. The selection of radiologic studies and their focus is based on the ophthalmologic examination where the ophthalmologist can often determine the suspected location of lesions in the anterior or posterior visual pathways. Furthermore, inspection of the eye, including adnexal structures and funduscopy, provides additional information in the clinical assessment of these patients. With technical advances in the last few years, CT and MR imaging can detect lesions and determine their location and extent with high sensitivity and specificity. This article discusses the radiologic, clinical, and pathologic evaluation of the optic nerve.

[Diagnostic difficulties in pigmented tumor of the optic nerve head. A case report]

Melanocytoma of the optic disc is a benign pigmented tumor located on the optic nerve head. Most cases are visually asymptomatic but in rare cases it can cause visual loss, which does not necessarily involve malignant transformation. We present a case of melanocytoma in a 49-year-old woman who presented with decreased vision in her left eye. The pigmented mass was in close continuity with the juxtapapillary adjacent choroid. Fluorescein angiography demonstrated hypofluorescence with adjacent disc edema. Ultrasonography disclosed a high internal reflectivity mass in the optic nerve head without retrobulbar extension. Magnetic resonance imaging (T1 weighted images) disclosed a hyperintense signal on the optic nerve head. The tumor was stationary for 20 months. This report emphasizes problems differentiating a melanocytoma from malignant melanoma of the optic nerve. Unusual features of melanocytoma (superior nasal location in the optic disc with an adjacent choroidal component, a decrease in visual acuity and disc edema surrounding the tumor) are discussed. Visual loss can be induced by optic neuropathy or retinal vascular obstruction. Melanocytomas grow very slowly over several years or remains stable, in contrast to malignant melanoma. In suspicious cases, close follow-up with serial fundus photographs is essential, although malignant transformation is exceptional.

Selected pigmented fundus lesions of children

BACKGROUND

Ocular cells that accumulate melanin pigment are derived from 1 of 2 sources, the optic vesicle or the neural crest. Migration and distribution of pigment containing cells may go awry during fetal development or these cells may be altered before or after birth either by local or systemic stimuli. Specific recognition patterns of pigment distribution often exist and may relate directly to a single disease process.

METHODS

Records of pediatric patients with disorders of pigment distribution in the ocular fundi who had been examined by the author were reviewed.

RESULTS

Five disorders with recognizable patterns of retinal pigment epithelium (optic vesicle derivation) disturbance (congenital hypertrophy of the retinal pigment epithelium, Gardner syndrome, chronic granulomatous disease, preserved para-arteriole retinal pigment epithelium in (autosomal-recessive) retinitis pigmentosa, and combined hamartoma of the retina and retinal pigment epithelium), and 5 disorders of cells originating from the neural crest (choroidal nevi, choroidal melanoma, melanocytoma, ocular melanosis, and oculodermal melanosis), were selected for illustration and discussion.

CONCLUSIONS

These arbitrarily selected groups of disorders affect or involve patterns of pigment deposition in the ocular fundus. These patterns are recognizable and distinguishable one from another but have different implications for treatment and follow-up. Progress in recognizing distinguishing characteristics, diagnostic implications, understanding, and treatment of these disorders during the past 40 years is compared and contrasted between the 2 groups.

Melanocytomas of the optic disk

PURPOSE

To evaluate the various forms of clinical presentation, the potential of growth, the risk of functional loss and the possibility of malignant transformation of optic disk melanocytomas in European patients.

DESIGN

Retrospective observational case control study.

METHODS

Evaluation of 37 cases of optic disk melanocytomas identified in the computer files of the ocular oncology unit of Jules Gonin Hospital to determine the clinical presentation of these tumors and the risk of complications.

RESULTS

The tumor was asymptomatic in 28 cases. Visual acuity was normal in 26 cases, subnormal in 10 cases, and in one case it was reduced to 0.1. Visual field defects were observed in 19 cases; the size and extent of the tumor and the degree of papilledema appeared to influence the severity of the visual field defect. Tumor growth was demonstrated in 6 of the 9 cases in which follow-up was for at least six years. In two cases there was presumed malignant transformation that was treated by accelerated proton beam radiotherapy.

CONCLUSIONS

Melanocytomas in white Europeans and those of European derivation are rarely symptomatic, have only a moderate effect on visual function and show a low rate of progression over long observation. The risk of tumor progression, although sometimes occurring as much as several years after the initial diagnosis, justifies a cautious approach with long-term regular surveillance of these patients.

Melanocytoma of optic disc in 115 cases: the 2004 Samuel Johnson Memorial Lecture, part 1

PURPOSE

To report clinical variations and the natural course of melanocytoma of the optic disc.

PATIENTS AND METHODS

A retrospective study was conducted on a consecutive series of patients with melanocytoma of the optic disc who were evaluated at the Ocular Oncology Service at Wills Eye Hospital. Demographic information and variations in appearance and size of the tumor and local ocular complications were noted. Frequency of tumor growth and malignant transformation was recorded. Clinical factors, including patient data and tumor features, were analyzed for their impact on visual acuity loss of 2 or more Snellen lines and the tumor growth, using Cox proportional hazards regression models. Kaplan-Meier survival estimates of probability of visual acuity loss of 2 or more Snellen lines and probability of tumor growth were performed as a function of time from the initial examination.

MAIN OUTCOME MEASURES

Visual acuity loss of 2 or more Snellen lines, tumor growth, and malignant transformation of the tumor.

RESULTS

There were 115 patients (116 eyes) with melanocytoma of the optic disc. The mean age at diagnosis was 50 years; 38% of patients were male and 62% of patients were female; 65% of patients were white, 29% of patients were African American, and 6% of patients were Asian, Hispanic, Indian, or Arabic. The lesion was unilateral in 99% of patients. Visual symptoms that seemed to be related to the melanocytoma were present in 24% of patients, and an afferent pupillary defect was noted in 9% of patients. Associated ocular abnormalities included ocular melanocytosis (8%), racial melanosis (7%), optic nerve hypoplasia (2%), and retinitis pigmentosa (1%). The melanocytoma was dark brown to black in 100% of patients. The mean tumor diameter was 2 mm and the mean thickness was 1 mm. Associated findings included a choroidal component (54%), retinal component (30%), optic disc edema (25%), retinal edema (16%), localized subretinal fluid (14%), retinal exudation (12%), retinal hemorrhage (5%), vitreous seeds (4%), and retinal vein obstruction (3%). Fluorescein and indocyanine green angiography typically showed persistent hypofluorescence of the lesion. Using Kaplan-Meier survival curves, related visual loss occurred in 18% of patients by 10 years, and minor tumor enlargement occurred in 11% of patients by 5 years and in 32% of patients by 10 years. Malignant transformation was documented in 2 patients (2%).

CONCLUSIONS

Although melanocytoma of the optic disc generally is considered to be a benign, stationary lesion, it can produce several local complications, can cause visual loss, can grow slowly, and, rarely, can undergo malignant transformation into melanoma. Patients with optic disc melanocytoma should undergo periodic ocular examination.

Transition from meningeal melanocytoma to primary cerebral melanoma

✓ The authors describe the first case of an intracranial transition of a melanocytoma into a primary malignant melanoma within a short time. A 37-year-old woman presented with progressive brainstem syndrome due to a tumor, originally diagnosed and treated 12 years earlier, that extended from the petroclival area to the anterior craniocervical junction. The histological workup following subtotal tumor resection of the initial tumor had revealed the typical features of a fibrous melanocytic meningioma without increased proliferation. Ten years after the patient had completed treatment for the melanocytic meningioma, control neuroimaging demonstrated growth of the residual tumor with compression of the brainstem. Another neurosurgical intervention revealed a dark tumor of hard consistency. At this time immunohistochemical examinations demonstrated melanocytic features (expression of vimentin, S100 protein, and melan A) of the lesion with focally increased proliferation (5% of Ki-67—positive cells) but no higher mitotic activity. Clinical signs of deterioration along with imaging-confirmed tumor progression precipitated another operation within 7 months. A neuropathological examination revealed epithelial and anaplastic changes and indicated that the MIB-1 indices were greater than 25%. Pleomorphic changes and a focal high mitotic activity led to the diagnosis of a primary cerebral malignant melanoma. The patient's later clinical course consisted of a rapid diffuse meningeal spread of the lesion throughout the entire brain and spine. Despite whole-brain and stereotactic radiation therapy as well as chemotherapy, the patient died 4 months after the last neuropathological diagnosis. Although grossly resembling a meningioma, melanocytomas lack the former's histological and immunohistochemical features. The biological behavior of a melanocytoma is variable and recurrence may happen after subtotal resection, but intracranial transition into a malignant melanoma has not been observed previously.

Malignant transformation of meningeal melanocytoma: A case report

Intracranial meningeal melanocytoma is an uncommon tumor that is considered benign. We formerly reported an intracranial meningeal melanocytoma. Here we report a extremely rare case of malignant transformation of this tumor. A 49-year-old man complained of a headache. Magnetic resonance scanning revealed a mass in the left frontal region. The patient underwent gross total removal of the tomor in 1994. The histological findings showed a meningeal melanocytoma. In 1998, he underwent gamma-knife surgery for local recurrence. An additional operation was performed in 1999 became tumor growth was not stopped. The tumor was partially excised by left frontal craniotomy. Histopathological examination revealed a malignant melanoma originating from a melanocytoma. The tumor was composed of a proliferation of severely atypical melanocytoid cells with slightly irregular nuclei and prominent nucleoli, associated with necrosis and hemorrhage. Mitotic figures were encountered occasionally. After six months, he died from cerebrospinal fluid dissemination of this tumor. To our knowledge, this is the first report of malignant transformation of an intracranial meningeal melanocytoma.

Therapeutic options for meningeal melanocytoma. Case report

Meningeal melanocytomas are uncommon lesions. They are generally considered to be benign tumors that derive from leptomeningeal melanocytes. A rare case of a metastatic spinal meningeal melanocytoma is presented. All relevant cases reported in literature since 1972, when the term "meningeal melanocytoma" was first used, were reviewed. Rates of tumor recurrence from 1 to 5 years were calculated for this rare lesion, based on published data and on additional information obtained from personal contact with most of the authors. Recurrency rates of 47 patients suitable for evaluation were correlated with the different therapeutic approaches. Complete tumor resection alone and incomplete resection alone followed by irradiation appeared to be superior to incomplete resection alone in terms of disease-free survival. Statistical significance was achieved for complete tumor resection at follow up between I and 4 years (range p = 0.010-0.050) and for incomplete resection combined with radiotherapy after 2 years (p = 0.034). Complete tumor resection should be considered the best therapeutic option, followed by incomplete resection combined with postoperative radiotherapy.

Melanocytoma of the ciliary body diagnosed by fine-needle aspiration biopsy

A 55-yr-old African American man was referred for evaluation of a mass involving the anterior choroid/ciliary body in his left eye. Dilated fundus examination revealed a large, deeply pigmented mass associated with an exudative retinal detachment. Ultrasonography demonstrated an elevated mass which involved the anterior uvea and showed low reflectivity by standardized A-scan. Cytologic examination of fine needle aspiration (FNA) biopsy from the tumor was interpreted as a melanocytoma. The patient developed a total retinal detachment and secondary glaucoma which led to enucleation of the eye. Histopathologic examination confirmed the diagnosis of melanocytoma. To our knowledge, this is the first report in which the diagnosis of uveal melanocytoma was established by FNA biopsy and later confirmed histopathologically.