Ординатура / Офтальмология / Английские материалы / Eye Pathology An Atlas and Text_Eagle_2010

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Intravitreal Tumor Cells

Retinoblastoma

Vitreous seeding common in advanced cases, poor prognostic sign

Primary Lymphoma of CNS and Retina (NHL-CNS)

("ocular reticulum cell sarcoma"- old, incorrect, outdated term) Bilateral vitritis, CNS lymphoma, dementia

Poor prognosis (mean survival 22 months) Most are large B cell lymphocytic lymphomas

Primary CNS lymphoma spares uvea, but sub-RPE deposits are common No systemic involvement outside CNS

Diagnostic vitrectomy reveals:

Atypical lymphocytes with prominent nucleoli, mitoses, abundant cellular necrosis

NOTE: Systemic lymphomas can involve vitreous secondarily in rare cases, but; uveal infiltration is more typical in such cases

Whipple's Disease- rarely mimics primary CNS lymphoma with bilateral vitritis, dementia, Cells PAS (+), contain bacteriaTropheryma whippelii

Metastatic Skin melanoma- predilection for retinal and vitreous metastasis

Vitreous Membranes (proliferative vitreoretinopathy, PVR) RPE, glial cells, myofibroblasts

Vitreous detachment allows cells to proliferate on inner and outer surface of retina, along scaffold of detached vitreous

Membranes cause fixed folds, inoperable RD

Proliferation on posterior face of detached vitreous responsible for funnel shape of chronic RD

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Anterior variant of PVRorganization of vitreous on pars plana inaccessible to vitrectomy; anterior loop retinal detachment, posterior traction on iris

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Surface Wrinkling Retinopathy (Cellophane retinopathy) Epiretinal glial proliferation; contraction of membrane folds ILM

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Illustrated Eye Pathology Outline

Part 4

©2006 Ralph C. Eagle, Jr., MD

Intraocular Tumors

Uveal Malignant Melanoma

Most common primary intraocular tumor in white adults

Risk Factors

Race

Uveal malignant melanoma is predominantly a tumor of blue-eyed Europeans Incidence in U.S. whites is 8.5 times greater that blacks

Incidence in USA is 21 times greater than in Taiwan (6 vs. 0.28/million) Tumors in blacks are larger, more pigmented, more necrotic and have same survival as tumors in whites.

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Age

Incidence increases with age, median age at diagnosis53 (AFIP), 59 (COMS) Larger tumors, poorer survival with increasing age:

* Survival after enucleation [ Non tumor deaths excluded]

Male = female in COMS study

Predisposing Lesions

Congenital ocular or oculodermal melanocytosis [Nevus of Ota] 1/400 lifetime risk of MM in Caucasians

Uveal neviestimated rate of malignant transformation- 1/10,00015,000/ year Neurofibromatosis

Dysplastic nevus syndrome (familial atypical mole melanoma syndrome) Ultraviolet lightmore common in blue eyes, inferior iris

Chemical carcinogens?? Pregnancy

BDUMP Syndrome- (Bilateral diffuse uveal melanocytic proliferation associated with systemic malignancy).

Remote effect of disseminated malignancy

Bilateral diffuse thickening of uvea with pigmented nodules. "giraffe skin" fundus Melanomas may arise from generalized low-grade spindle cell proliferation

Clinical Presentation of Uveal Melanoma

Incidental Finding on routine examination Visual Loss

Retinal Detachment [ solid and/or serous, rarely hemorrhagic], foveal overhang, CME (peripheral tumors), cataract formation [CB tumors], vitreous hemorrhage [ rare, usually with retinal perforation ]

Extrascleral Extension [ anterior or orbit mass with proptosis] Glaucoma

Iris heterochromia

Inflammatory signs mimicking endophthalmitis or orbital cellulitisnecrotic tumors Unsuspected tumor diagnosed in pathology lab in blind painful eye

Gross Pathology

Choroidal Tumors-Most common location

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Pathologic classification by size: (LTDlargest tumor diameter) SmallLTD ≤ 10 mm- most are discoid tumors confined to choroid

MediumLTD 1115 mm

Most break through Bruch’s membrane and grow in subretinal space Typical mushroom or collar button configuration (63%)

Dilated vessels in head of mushroom caused by cinch-like effect of Bruch’s membrane on waist of tumor.

LargeLTD > 15 mm

Tumor invades and destroys ocular tissues, may fill globe Extrascleral extension more common

May be diffuse infiltrating type

Uncommon, grows laterally with little choroidal thickening Extrascleral extension more common

Ciliary body melanomas

Less common that choroidal tumors – poorer prognosis Diagnostic delayasymptomatic, no RD

Tend to have a more spherical shape

Can invade anterior chamber anterior ("tip of the iceberg")

Diffuse type of malignant melanoma may cause ring configuration around circumference of angle and ciliary body. Prone to anterior extrascleral extension

Can cause cataract; sentinel vessels, CME

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Cytology and Histopathology

Callender Classification [modified by McLean et al, 1978] Association between mortality and cytology or cell type of melanoma

Spindle cells

Bipolar cells with spindle-shaped cytoplasmarranged in parallel fascicles Grow as syncytiumcellular margins indistinct by LM

Spindle A- slender cigar-shaped nucleus with finely dispersed chromatin and indistinct nucleolus. Nuclei often have chromatin stripe or streak caused by fold in nuclear membrane (most benign)

Spindle B- plumper, oval nucleus with coarser chromatin and a more prominent nucleolus

Intermediate cells- Nuclear characteristics intermediate between spindle B and epithelioid

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