How does melanoma appear?

It appears as a brown or yellow tumor in the back of the eye and is not visible to the patient. Based on tumor thickness, choroidal melanoma is classified into small (0-3mm), medium (3-8mm), and large (>8mm). Small tumors might resemble a benign choroidal nevus or freckle. Risk factors have been identified by members of the Wills Oncology Service to find small melanoma for early detection. These include:

  1. Thickness > 2 mm
  2. Subretinal fluid over the tumor
  3. Symptoms of flashing lights, floaters, or vision loss
  4. Orange pigment over the tumor
  5. Margin of the tumor near the optic disc
  6. Ultrasound hollowness
  7. Halo absent
  8. Drusen absent

Medium and large choroidal melanoma can assume a dome shape or even a mushroom shape appearance as they enlarge. Often they produce overlying subretinal fluid (retinal detachment) that is associated with vision loss. Growth of the tumor through the wall of the eye into the overlying soft tissues is called extraocular extension and is more worrisome.