Spencer The eye consists of many different structures. It contains the eyelid, cilia, lacrimal glands, drainage apparatus, and conjunctiva.1 Cancers of the eye can include ocular malignancies, uveal and retinal tumors, optic glioma, and orbital malignancies. Overall, eye cancers can be caused by a variety of things including eye color, sun exposure, and even occupational exposure to certain chemicals.
Ocular Malignancies: Basel and Squamous Cell Carcinoma of the Eyelid. Radiation therapy is used most often for these cases which have a 90% cure rate.1
Uveal Tumors: The most common forms of these include metastatic tumors of the posterior uvea and malignant melanoma of the uvea. These specific forms account for 90% of all cases that present in the eye.1
Retinal Tumors: This form of cancer is the most common intraocular malignancy in children and accounts for 25% of all primary malignant tumors of the eye.1 This form also presents 1/3 bilateral, and 2/3 unilateral in most cases.1
Optic Glioma: This form of eye cancer is most prevalent in children under 15 years of age. It also includes only 1% of all central nervous system tumors, of which 50% involve the optic chiasm.1
Orbital Tumors: These types of tumors include RMS (Rhabdomyosarcoma), malignant lymphoma of the orbit, and lacrimal gland tumors.
The overall 5 year survival rates from eye and orbital cancers taken from 18 geographical areas include 81.7%.2 The overall lifetime risk that a person will end up with cancer of the eye and or orbit can include .08%.2
Etiology:
Pablo There are several factors that are associated with certain eye malignancies. Among them are the following:
Race and ethnicity: studies show that the incidence is much higher in whites than in African Americans or Asians.
Eye Color: people with lighter eye color are at higher risk of developing malignancies of the eye
Sun exposure
Occupation: Welders, chemical workers are also at a higher risk
Having other diseases like the human immunodeficiency virus / acquired immunodeficiency syndrome (HIV)/AIDS), the Humana Papillomavirus (HPV)
People on antirejection drugs for organ transplants
Inherited faulty genes3
Signs & Symptoms:
Becky
Common symptoms of the eye include: a growing dark spot on the iris, sensation of flashing lights, alteration in the shape of the pupil and blurring/loss of vision.
Signs & Symptoms of different types: ¨ Melanoma—loss of vision, detached retina, pain and bleeding ¨ Choroidal Nevus—loss of peripheral or central vision; can look like a mole ¨ Conjunctival Tumor—pain and loss of vision; grow on the external surface of the eye ¨ Eyelid Tumors—pain, swelling, vision loss and impairment of the tear duct ¨ Orbital Tumors—bulging of the eye, retinal detachment; usually develop over the eye socket ¨ Retinoblastoma—common in children; whiteness of pupil and swelling4
Diagnostic Procedures:
Adam The following diagnostic tests are used for cancers of the eye:5
Ultrasound
Fluorescein angiography
Fine needle biopsy
CT Scan
PET Scan
In addition to these tests, eye melanomas can be discovered during a regular eye examination.
Histology:
Megan This table explains the different types of histology's that can occur within the eye, and percentage frequency of occurrence. This table was found on nature.com explaining the incidence of eye cancer in Taiwan, and it was an 18 year review.6 The longevity of the study and the number of cases studied increases both its validity and strength.
Subsite
Histology
No. of cases
Frequency (%)
Eyeball (190.0)a
Melanoma
51
83.6
Squamous cell carcinoma
3
4.92
Other cell types
7
11.5
Total histologically confirmed
61
100
Orbit (190.1)b
Lymphoma
59
41.5
Squamous cell carcinoma
19
13.4
Rhabdomyosarcoma
10
7.04
Carcinoma NOS
9
6.34
Adenocarcinoma
8
5.63
Other cell types
37
26.1
Total
142
100
Lacrimal gland (190.2)
Adenoid cystic carcinoma
14
45.2
Lymphoma
6
19.3
Adenocarcinoma
4
12.9
Other cell types
7
22.6
Total
31
100
Conjunctiva (190.3)
Squamous cell carcinoma
50
43.5
Melanoma
27
23.5
Lymphoma
23
20.0
Carcinoma NOS
12
10.4
Other cell types
3
2.60
Total
115
100
Cornea (190.4)
Squamous cell carcinoma
4
44.5
Carcinoma NOS
3
33.3
Other cell types
2
22.2
Total
9
100
Retina (190.5)
Retinoblastoma
259
97.0
Other cell types
8
3.00
Total
267
100
Choroid (190.6)
Melanoma
32
88.9
Other cell types
4
11.1
Total histologically confirmed
36
100
Lacrimal duct (190.7)
Carcinoma NOS
4
28.6
Squamous cell carcinoma
3
21.4
Adenocarcinoma
3
21.4
Other cell types
4
28.6
Total
14
100
Other sites (190.8, 190.9)c
Melanoma
16
27.6
Squamous cell carcinoma
14
24.1
Carcinomas NOS
10
17.2
Adenocarcinoma
4
6.90
Other cell types
14
5.17
Total
58
100
Lymph node drainage:
Kevin Tsai
Up to now lymphatics of the eye could not be pointed out. Research is still underway to determine the role of lymphatics of eye cancer.
Metastatic spread:
Erin Secondary Intraocular tumors are those that start somewhere else and then spread to the eye.7 These are actually more common than primary eye tumors. The most common cancers that spread to the eye are breast and lung cancer. Less common sites of origin include the prostate, kidney, thyroid, and gastrointestinal tract.8 Lymphoma and leukemia can also spread to the eye and orbit. The most common area for ocular metastasis is in the choroid (vascular layer) of the eye.
Grading:
Spencer The most common forms of cellular classifications of the eye include Spindle-A cells, Spindle-B Cells, Epithelioid cells, and Intermediate cells.2 The tumor is given a grade (G) to describe the composition of its cells. Usually a lower grade indicates a better prognosis.9
GX - The grade cannot be evaluated.
G1 – A Spindle Cell Melanoma
G2 – A Mixed Cell Melanoma
G3 – An Epithelioid Melanoma
Staging:
Pablo The American Joint Committee on Cancer (AJCC) advocates the TNM staging system. This system is based on the following information.
T used to describe the size of the primary tumor and if adjacent structures have been invaded
N indicates if the disease has spread to regional lymphatics
M gives information on whether the tumor has spread to distant organs10
The COMS staging system. This system was developed by the Collaborative Ocular Melanoma Study (COMS) group and as implied by its name, it focuses on intraocular melanoma. This system divides eye melanomas into small, medium, and large. Tumor size classifications according to boundary lines used in a Collaborative Ocular Melanoma Study (COMS) are as follows:
Small: Range from 1.0 mm to 3.0 mm in apical height and largest basal diameter of 5.0 to 16.0 mm.[1]
Medium: Range from 3.1 to 8.0 mm in apical height and a basal diameter of not more than 16.0 mm.[2]
Large: Greater than 8.0 mm in apical height or a basal diameter more than 16.0 mm, when the apical height is at least 2.0 mm.10
The Reese-Ellsworth staging system Developed in the 1960’s, the Reese-Ellsworth staging system is used to classify retinoblastomas that have not metastasize to other parts of the body. This system includes terms such as favorable or unfavorable and doubtful used to describe the like hood of the disease treated effectively while the affected eye is preserved. It is divided into 5 categories or groups, each one representing the probability of preserving the eye and sight while controlling the disease.
Group 1 (very favorable for saving or preserving the eye)
Group 2 (favorable for saving or preserving the eye)
Group 3 (doubtful for saving or preserving the eye)
Group 4 (unfavorable for saving or preserving the eye)
Group 5 (very unfavorable for saving or preserving the eye)11
The International Classification for Intraocular Retinoblastoma A newer classification for retinoblastoma is divided into 5 groups labeled A through E
Group A: Small tumors (3 mm across or less) that are confined to the retina and are not near important structures such as the optic disk (where the optic nerve enters the retina) or the foveola (the center of vision).
Group B: All other tumors (either larger than 3 mm or small but close to the optic disk or foveola) that are still confined to the retina.
Group C: Well-defined tumors with small amounts of spread under the retina (subretinal seeding) or into the gelatinous material that fills the eye (vitreous seeding).
Group D: Large or poorly defined tumors with widespread vitreous or subretinal seeding. The retina may have become detached from the back of the eye.
Group E: The tumor is very large, extends near the front of the eye, is bleeding or causing glaucoma (high pressure inside the eye), or has other features that mean there is almost no chance the eye can be saved.11
Radiation side effects:
Becky
Radiation side effects of treatment to the eye can range from cataracts, gradual vision loss, and optic nerve damage and perhaps in extreme cases blindness.
Prognosis:
Adam The prognosis for cancers of the eye depend primarily on the size of the tumor, the location of the tumor, and the extent of extraocular invasion.12 The general 5 year survival rate for non-metastatic cancers of the eye sits at 80%. However, due to the rarity of eye cancers, the data on this isn't as extensive as many other types of cancers.12
Treatments:
Megan As with all radiation treatments, the intention is to design a conformal treatment regimen that treats the tumor at an optimal dose with minimal normal tissue toxicity.13 But, when treating the eye, the entire retinal area must be treated to eliminate the recurrence possibilities in the anterior of the eye. If instead of treating the whole, a lens sparing treatment is used, the chances for recurrence increases from 1.4% to 19%.2 Beam arrangements are typically laterals, a single anterior, a single lateral, or a combination of the two.13 Left picture represents an anterior beam only and the right depicts an anterior combined with a lateral. If laterals are chosen the 5-10 degree posterior gantry tilts should be added to avoid dose to the contralateral lens, cornea, and brain.2 D shaped blocks are typically the outcome when avoiding these areas. This is a picture of the D shaped block often used with ocular radiation. Retinoblastoma can be adequately treated if a dose of 40-45 gray (Gy) is administered in 1.5-2.0 Gy fractions when external beam is used alone.2 This dose can be reached using 15-18 MeV beams or 4-6 MV. If chemo and radiation are combined, the a reduction in radiation is required to 35-40 Gy.2
TD 5/5:
Kevin Tsai
Lens 1000 cGy – Cataract.14
Retina 4500 cGy - Blindness
Optic Chiasm 4500 cGy – Blindness
Optic Nerve 5000 cGy – Blindness
References:
Chao C, Perez C, Brady L. Radiation Oncology Management Decisions. 3rd ed. PA: Lippincott Williams and Wilkins; 2011:193-202.
The eye consists of many different structures. It contains the eyelid, cilia, lacrimal glands, drainage apparatus, and conjunctiva.1 Cancers of the eye can include ocular malignancies, uveal and retinal tumors, optic glioma, and orbital malignancies. Overall, eye cancers can be caused by a variety of things including eye color, sun exposure, and even occupational exposure to certain chemicals.
There are several factors that are associated with certain eye malignancies. Among them are the following:
Common symptoms of the eye include: a growing dark spot on the iris, sensation of flashing lights, alteration in the shape of the pupil and blurring/loss of vision.
Signs & Symptoms of different types:
¨ Melanoma—loss of vision, detached retina, pain and bleeding
¨ Choroidal Nevus—loss of peripheral or central vision; can look like a mole
¨ Conjunctival Tumor—pain and loss of vision; grow on the external surface of the eye
¨ Eyelid Tumors—pain, swelling, vision loss and impairment of the tear duct
¨ Orbital Tumors—bulging of the eye, retinal detachment; usually develop over the eye socket
¨ Retinoblastoma—common in children; whiteness of pupil and swelling4
The following diagnostic tests are used for cancers of the eye:5
In addition to these tests, eye melanomas can be discovered during a regular eye examination.
This table explains the different types of histology's that can occur within the eye, and percentage frequency of occurrence. This table was found on nature.com explaining the incidence of eye cancer in Taiwan, and it was an 18 year review.6 The longevity of the study and the number of cases studied increases both its validity and strength.
Up to now lymphatics of the eye could not be pointed out. Research is still underway to determine the role of lymphatics of eye cancer.
Secondary Intraocular tumors are those that start somewhere else and then spread to the eye.7 These are actually more common than primary eye tumors. The most common cancers that spread to the eye are breast and lung cancer. Less common sites of origin include the prostate, kidney, thyroid, and gastrointestinal tract.8 Lymphoma and leukemia can also spread to the eye and orbit. The most common area for ocular metastasis is in the choroid (vascular layer) of the eye.
The most common forms of cellular classifications of the eye include Spindle-A cells, Spindle-B Cells, Epithelioid cells, and Intermediate cells.2 The tumor is given a grade (G) to describe the composition of its cells. Usually a lower grade indicates a better prognosis.9
The American Joint Committee on Cancer (AJCC) advocates the TNM staging system. This system is based on the following information.
The COMS staging system.
This system was developed by the Collaborative Ocular Melanoma Study (COMS) group and as implied by its name, it focuses on intraocular melanoma. This system divides eye melanomas into small, medium, and large.
Tumor size classifications according to boundary lines used in a Collaborative Ocular Melanoma Study (COMS) are as follows:
The Reese-Ellsworth staging system
Developed in the 1960’s, the Reese-Ellsworth staging system is used to classify retinoblastomas that have not metastasize to other parts of the body. This system includes terms such as favorable or unfavorable and doubtful used to describe the like hood of the disease treated effectively while the affected eye is preserved. It is divided into 5 categories or groups, each one representing the probability of preserving the eye and sight while controlling the disease.
The International Classification for Intraocular Retinoblastoma
A newer classification for retinoblastoma is divided into 5 groups labeled A through E
Radiation side effects of treatment to the eye can range from cataracts, gradual vision loss, and optic nerve damage and perhaps in extreme cases blindness.
The prognosis for cancers of the eye depend primarily on the size of the tumor, the location of the tumor, and the extent of extraocular invasion.12 The general 5 year survival rate for non-metastatic cancers of the eye sits at 80%. However, due to the rarity of eye cancers, the data on this isn't as extensive as many other types of cancers.12
As with all radiation treatments, the intention is to design a conformal treatment regimen that treats the tumor at an optimal dose with minimal normal tissue toxicity.13 But, when treating the eye, the entire retinal area must be treated to eliminate the recurrence possibilities in the anterior of the eye. If instead of treating the whole, a lens sparing treatment is used, the chances for recurrence increases from 1.4% to 19%.2 Beam arrangements are typically laterals, a single anterior, a single lateral, or a combination of the two.13
Left picture represents an anterior beam only and the right depicts an anterior combined with a lateral.
If laterals are chosen the 5-10 degree posterior gantry tilts should be added to avoid dose to the contralateral lens, cornea, and brain.2 D shaped blocks are typically the outcome when avoiding these areas.
This is a picture of the D shaped block often used with ocular radiation.
Retinoblastoma can be adequately treated if a dose of 40-45 gray (Gy) is administered in 1.5-2.0 Gy fractions when external beam is used alone.2 This dose can be reached using 15-18 MeV beams or 4-6 MV. If chemo and radiation are combined, the a reduction in radiation is required to 35-40 Gy.2