No, glaucoma isn’t cancer. It’s a chronic eye condition that may lead to blurry vision and vision loss due to damage to the optic nerve.

Glaucoma results from the pressure caused by fluid accumulation inside the eye, which may damage the optic nerve permanently if left untreated. The optic nerve connects the eye structures to the brain, sending sensory information that is important for vision.

Cancer refers to a condition that develops when abnormal cells grow out of control and affect immediate and nearby tissues.

Both glaucoma and cancer of the eye may lead to temporary or permanent vision loss, among other vision-related challenges.

Glaucoma is a group of conditions that involve increased pressure inside the eye that affects the optic nerve.

There are four types of glaucoma:

  • Open-angle glaucoma: This is the most common type of glaucoma. In this condition, eye pressure increases slowly and gradually due to a partial blockage in the eye’s natural drainage system.
  • Angle-closure glaucoma: Also called closed-angle glaucoma, this type of glaucoma causes rapid and sudden increases in eye pressure due to the iris, the colored part of the eye, blocking the drainage system. Closed-angle glaucoma is painful. It’s considered a medical emergency.
  • Congenital glaucoma: This type of glaucoma occurs when the eye’s drainage system doesn’t develop as it should, causing high pressure inside a child’s eye. It usually runs in families.
  • Secondary glaucoma: When you develop glaucoma as a result of another condition or an injury to the eye, a doctor may diagnose secondary glaucoma. This type of glaucoma may also be a side effect of some medications.

Early stages of open-angle glaucoma may not cause evident symptoms. It’s mostly diagnosed by an eye doctor called an ophthalmologist during a specialized eye exam. As the condition goes untreated for a longer time, gradual vision loss may be the first symptom.

Additional symptoms of glaucoma may include:

Symptoms vary depending on the type of glaucoma. For instance, symptoms such as eye pain, redness, and swelling are most common with angle-closure glaucoma.

Eye cancer is an abnormal growth that affects the eye and nearby tissues.

The most common type of eye cancer is ocular melanoma. It typically starts in the cells that give eyes their color.

Other possible types of eye cancer include:

  • Squamous and basal cell carcinomas: These types of cancer affect specific cells and usually start in the skin’s most superficial layers. Most eyelid cancers are basal cell carcinomas.
  • Retinoblastoma: This type of rare eye cancer is most common in children under 5 years old. The cancer starts in the retina, a thin layer of tissue at the back of the eye. The retina detects light and color, and then sends this information to the brain to process. This is how the eye forms images. When the retina is damaged, vision is compromised.
  • Orbital rhabdomyosarcoma: This rare type of eye cancer develops around the eye, including the eyelids and orbit (the hollow space where the eye fits, typically referred to as the eye socket).
  • Intraocular lymphoma: This rare cancer is a form of B-cell lymphoma that affects the tissues inside the eye and develops from abnormal white blood cells.

Just like with glaucoma, symptoms of eye cancer may vary depending on the type. However, some cancer symptoms that may feel or look similar to glaucoma may include:

  • gradual vision loss
  • blurry vision
  • floaters
  • eye pain
  • changing or growing dark spots on the iris
  • chronic eye irritation
  • lumps on eyelids or eyeballs
  • change in how the eye moves or feels in the eye socket

Glaucoma is the second most common cause of vision loss for adults in the United States. On the other hand, most types of eye cancer are rare.

According to the Glaucoma Research Foundation, more than 4 million U.S. adults live with glaucoma. Comparatively, the American Cancer Society reports that about 3,140 U.S. adults receive an eye cancer diagnosis each year.

Glaucoma is not a known risk factor for eye cancer. However, a 2020 study suggests a link between glaucoma and an overall higher risk of cancer in other organs, particularly for women and people under 65 years old.

For women with glaucoma, the study found the risk was higher for colorectal, lung, renal cancer, and lymphoma. For people with glaucoma under 65 years old, the risk was higher for renal, skin, and prostate cancers.

More research is needed to establish a clearer link between glaucoma and cancer, particularly eye cancer, and to understand the potential action mechanisms between the two.

Glaucoma is not a usual symptom of eye cancer, but it may be a complication of eye cancer. Abnormal growths inside and around the eyes may lead to increased pressure inside the eye, which could cause glaucoma.

Glaucoma and eye cancer may cause blurry vision, eye pain, and vision loss. However, these are different conditions that don’t have a common link.

Glaucoma happens when fluid buildup increases pressure inside the eye, leading to damage to the optic nerve. Eye cancers are rare and result from abnormal cell growth inside or around the eye structures.