## Keratoacanthoma
- Rapidly growing but spontaneously resolving tumour of the epidermis
- Can mimic an SCC
- Nodule that grows over only a few weeks
    - Elevated, “heaped” shoulder
    - Central ulcer/crater
    - Typically resolves within 2-3 months but can leave a scar

- Histologically
    - Central mass of keratin (pink with H&E stain)
    - Hyperplastic epidermis with clear demarcation between this raised edge and normal skin surface
    - Demonstrate hyperkeratosis (of the epidermis) and sometimes also dyskeratosis (keratinisation within the dermis)

## Epidermoid cyst
- Demonstrate dyskeratosis (purely)
- Histologically: keratin-filled cavity within the dermis lined by keratinised stratified squamous epithelium

## Basal cell carcinoma
- \>90% of malignant eye tumours
- Caucasians over 50 years old
- Associated with:
    - Sunlight exposure
    - Gorlin-Goltz syndrome (aka basal cell naevus syndrome). Autosomal dominant mutation of PTCH gene on 9q
    - Xeroderma pigmentosa: autosomal recessive, extreme sensitivity to UV light
    - Albinism: usually autosomal recessive (lack of melanin)
    - Bazex syndrome: X-linked dominant disorder of hair follicles
    - Male gender
    - Arsenic exposure
    - Immunosuppression
    - Fair skin/caucasian
    - Smoking

- Appearance
    - Nodular (or solid)
    - Central ulcer
    - Rolled edge
    - Morphoeic type: scirrhous (hard/fibrous) plaque resembling scar
    - Occasionally pigmented

- Medial canthus is most common location (48%) followed by lower eyelid, upper lid and lateral canthus (least common)
    - Medial canthal BCC tends to be more aggressive and more likely to be deeply invasive

<HotTopic>
 Histological types of BCC

- Nodular (most common): well-defined islands of proliferating basal cells with peripheral palisades. Cystic degeneration can occur (nodulocystic)

- Superficial: scaly plaque showing lobules of cells budding into superficial dermis from the epidermis or localised to the dermal-epidermal junction. There may be big gaps between the collections of cells

- Infiltrative/sclerosing: morphoeic clinically. More aggressive. Strands of tumour cells in a fibrous stroma and ill-defined border with reduced <span className='font-semibold'>peripheral palisading</span>

- Micronodular: more aggressive. Multiple small nodular collections of cells.

</HotTopic>

- Management: surgical excision
    - Superficial BCCs can be treated with imiquimod: an immune response modulator that stimulates apoptosis in BCC cells. Clearance rate of 82-90%
    - Cure rates approach 95% ie 5% recurrence rate depending on treatment and histological subtype
    - Metastasis occurs on 0.1% typically lungs and bone
    - There is a 35% risk of BCCs in other sites

## Squamous cell carcinoma
- 1-5% of eyelid cancers
- Associated with:
    - Sunlight exposure
    - Immunosuppression

- Appearance:
    - Fast growing
    - Nodular ulcer
    - Papillomatous growth
    - May have overlying keratinous horn

- Disseminates via lymphatics: preauricular nodes (upper lid) and submandibular nodes (lower lid)

- Histology:
    - Well-differentiated: pink cytoplasm, intercellular bridge, keratin pearls
    - Spindle cell morphology rare: more aggressive

- Can affect the cornea and conjunctiva with identical histology. Associated with AIDS

## Sebaceous cell carcinoma
- &lt;1% of eyelid tumours
- Can mimic benign inflammatory and malignant processes
- Typically arises from meibomian glands or glands of Zeis
- More common in upper lid
- Risk factors
    -Age (elderly)
    - Female
    - **Muir-torre syndrome**: sebaceous neoplasm-visceral carcinoma. Loss of mismatch repair genes hMSH2 and hMLH1. Poor prognosis.

- Features
    - Nodule: firm nodule resembling a chalazion (always suspect in recurrent chalazion)
    - Spreading: diffuse infiltration resembling chronic blepharoconjunctivitis +/- loss of lashes
    - May mimic chalazion, SCC and BCC

- Histology:
    - Nodular: lobules of tumour cells with foamy/vacuolated cytoplasm
    - Diffuse: individual cells invading epithelium (Pagetoid spread)
    - Variable differentiation
    - **Oil red O** stains the fat within malignant cells red

- \>6 months delay to diagnosis significantly worsens mortality
- Lymph node metastasis affects 8-28%
- Pagetoid spread: consider mapping biopsies of the conjunctiva

- Management may involve parotidectomy as frequently spreads here as well as wide local excision, lymph node clearance +/- exenteration

## Merkel cell carcinoma of the eyelid
- Very rare
- Neuroendocrine malignancy
- Commoner in elderly patients
- Rapid aggressive growth
- Clinical features
    - Non-tender **purple** nodule (violaceous red colour)
    - Fusiform shape
    - Palpable lymph nodes
    - Overlying telangiectasia

- Poor systemic prognosis
- Consider orbital MRI to exclude orbital invasion
- Immunohistochemical staining with **neuron specific enolase** is a hallmark. Otherwise histology shows highly undifferentiated tumour

## Naevi
- Begin junctional, become compound then later, intradermal
    - Junctional: within epidermis. Flattest, darkest, **highest malignant potential**
    - Compound: span epidermis and dermis. Slightly elevated, moderately pigmented, intermediate malignant potential
    - Intradermal: within dermis. Most elevated, least hyperpigmentation and **lowest malignant potential**


Tumours, masses and neoplasia

Adnexal masses

Intro

FRCOphth Part 2 Study Notes

Tumours overview

Uveitis

Uveitis background

Anterior uveitis

Intermediate uveitis

Uveitis in JIA

Uveitis with JIA

Retinal vasculitis

Sarcoidosis

Behcet's disease

Toxoplasmosis

Strabismus

Overview

Viral uveitis

Esotropia

Fungal uveitis

Mycobacterial uveitis

Exotropia

Spirochaetal uveitis (including Syphilis)

Melanoma

Nematode uveitis

Retinoblastoma

Retinoblastoma (for Part 2)

Incomitent

Voyt-Koyanagi-Harada syndrome

Conjunctival intraepithelial neoplasia

Vertical deviations

Orbit and ocular adnexae

Orbit

Sympathetic ophthalmia

AV Malformations and hamartomas

Arteriovenous malformations and hamartomas

Restriction syndromes

Paediatrics

Leucocoria

Congenital Cataract

Paediatric Glaucoma

Retinopathy of prematurity

Retinopathy of Prematurity

ROP-like disorders

Congenital nasolacrimal duct obstruction

White dot syndromes

Aniridia: Short Arm 11 Deletion (11p13)

Choristomas

Management Of Amblyopia

Alphabet patterns

Iris Nodules

Scleritis

Meningioma

Strabismus surgery

Optic nerve glioma

Lymphoma

Extraocular Muscles

Rhabdomyosarcoma

Idiopathic orbital inflammation

Orbital neuroblastoma

Anterior Persistent Foetal Vasculature

Lacrimal system

Metastatic lesions

Surgical Retina

Retinal Detachment

Vitreoretinal Interface And Macular Hole

Epiretinal Membrane

Medical Retina

Diabetic Eye Disease

Orbital Blood Vessels

Retinal Vascular Disease

Macular Degeneration

Central Serous Chorioretinopathy (CSCR)

Sickle Cell Retinopathy

Retinitis Pigmentosa

Albinism

Retinal Telangiectasias

Miscellaneous Retinopathies

Atropine And Myopia Progression

Pharmacology

Side Effects Of Systemic Drugs

Foetal Alcohol Syndrome

Neuro-ophthalmology

Optic Neuropathy

Papilloedema

Idiopathic Intracranial Hypertension

Chiasmal Disorders

Retrochiasmal Disorders

Migraine

Paranasal Sinuses

Supranuclear Motility Disorders

Third Nerve Palsies

Fourth Nerve Palsies

Sixth Nerve Palsies

Seventh Nerve Palsies

Anisocoria

Myasthenia Gravis

Myopathies

Blepharospasm

Functional Visual Loss

Lacrimal Glands

Phakomatoses

Developmental diseases

Tear Film

Eyelids

Blinking

Lid Malpositions

Anterior segment - ocular surface

Conjunctiva

Conjunctivitis

Sclera

Pigmented Conjunctival Lesions

Squamous Cell Carcinoma Of The Conjunctiva

Ocular Cicatricial Pemphigoid

Cornea

Corneal Structure And Development