Part 7: Tumors of The Eye (Orbit)- Intraocular Tumors

term. Intraocular Tumors

def. any tumors in the eyeball

Types of Intraocular tumors

1. retinoblastoma (in retina)

2. intraocular melanoma (melanoma in the eye)

retinoblastoma

Retinoblastoma epidemiology

Usually occur before age 2

Nearly all occur before age 4

Spontaneous regression in 1% of patients

Which cancer has the highest regression rate of any TRUE Malignancy? (i.e. it is cancer, not a benign tumor)

retinoblastoma

spontaneous regression in 1% of patients

Retinoblastoma etiology

related to chromosome 13- a tumor suppressing gene

• since retinoblastomas are caused by a tumor suppressing gene, it leaves patients susceptible to other cancers later in life

What other cancers are retinoblastoma patients susceptible to?

sarcomas

Retinoblastoma typical presentation

cat’s eye reflex

Diagnosis for retinoblastoma

1. ophthalmoscopy

2. CT scan

Staging system for retinoblastoma

Reese-Ellsworth system

REtinoblastoma = REese

invasion pattern & mets for retinoblastoma

Spreads directly along optic nerve to cranial cavity

Can also go thru blood to various organs, though rare

Treatment for retinoblastoma: Yes/No and type of treatment done

1. Surgery

2. RTT

3. Chemo

(Surgery/ RTT) has been the classic way to manage retinoblastomas

RTT

If surgery has better cure rates than RTT, why would a patient choose surgery over RTT?

To keep the eye

3 Reasons why one would treat retinoblastomas with RTT

1. To keep the eye

2. If tumor is bilateral (to keep vision)

3. If after surgery, there are positive margins at the optic nerve (pic below)

What is a con of choosing to treat retinoblastomas with RTT instead of surgery?

high risk of developing late malignancy

If retinoblastoma is treated with RTT teletherapy:

1. Dose

2. Field arrangment

3. Structures to avoid treating and their tolerances

1. Dose: 40Gy

2. Field arrangement:

   1. Various oblique fields (to avoid txing lens)

   2. IMRT- better

3. Lens- 1000cGy

4. lacrimal glands- 30 Gy

5 year survival for retinoblastoma

80%

the younger the patient the better

intraocular melanoma (melanoma inside the eye)

what is the most common intraocular cancer? 👑

intraocular melanoma

True or False: Intraocular Melanoma is the leading cause of enucleations

False:

1st: trauma

2nd: intraocular melanoma

makes since it is #2 since it is the #1 intraocular tumor

epidemiology for intraocular melanomas

1. most common intraocular cancer

2. 2nd leading cause of enucleations

3. more common in adults

Etiology for intraocular melanomas

unknown

Treatment for retinoblastoma: Yes/No and type of treatment done

1. Surgery

2. RTT

3. Chemo

5 year survival for intraocular melanomas

not given