Neurofibromatosis (NF) is a condition in which an individual develops tumors in the three most vital parts of their nervous system: the brain, spinal cord, and nerves. The disorder passes from one generation to the next in families through genetic mutations. Thankfully, neurofibromatosis tumors are not always cancerous. Based on the symptoms, the disease can be categorized into three distinct types as follows.

Neurofibromatosis type 1
This is the most common of the three and is usually diagnosed in early childhood. The symptoms of neurofibromatosis type 1 include multiple freckles in the armpit or groin area, tiny growths in the iris of the eye, as well as flat, brown spots on the skin called café-au-lait spots. Some people may also experience bone deformities and neurofibromas on or under the skin. If tumors develop on the optic nerve, one may even start losing their eyesight. Neurofibromatosis type 1 can be further classified as cutaneous, subcutaneous, and plexiform based on the type and position of the tumors.

Neurofibromatosis type 2
This type of neurofibromatosis is less common than type 1. It is usually diagnosed in the late teens or early 20s, but some may remain asymptomatic until they turn 40 or older. People with this type of neurofibromatosis do not typically observe café-au-lait spots or skin tumors. Instead, they develop tumors on their eighth cranial nerve, which is connected directly to the ear canal on the left and right sides of the brain. As a result, patients observe symptoms relating to hearing loss or lack of balance. The other signs include dizziness, uncoordinated walking, weakness in the facial muscles, and cataracts at an early age.

Neurofibromatosis type 3
Neurofibromatosis type 3, commonly known as schwannomatosis, is the rarest type of the disease and is mainly diagnosed in early adulthood. In this type of neurofibromatosis, the patient may start developing tumors that contain Schwann cells, also known as schwannomas. These tumors typically develop on the cranial, spinal, and peripheral nerves. Unfortunately, the condition can go undiagnosed for a long time since the only prominent symptom is the pain in the tumor area. The other signs include weakness or numbness in the fingers and toes.