neuroma

A neuroma (pronounced /nuːˈroʊmʌ/) is a growth or tumor of nerve tissue.^[1] (Neuro- is from the Greek for nerve, whereas the suffix -oma denotes swelling.) Just as the Latin word for swelling (tumor) is now restricted to neoplasias, the equivalent Greek suffix -oma has shared in that fate. Thus, the typical modern usage of neuroma is for nerve tumors. However, many of the older, more general uses persist.^[2]

Neoplastic neuromas

Neoplastic neuromas are tumors of nerves, although the term can also be applied more generally for a tumor of nervous system tissue. They can be derived from a variety of the cell types that constitute nervous tissue, including glial cells and neurons, and can be either benign or malignant (i.e. cancerous). Many mistakenly assume that the Greek stem neur in neuroma refers to neurons rather than to nerves. This is not the case, and in fact, most instances of the word refer to non-neuronal tissue.

• Neurinoma (Neurilemmoma) - a benign slow growing tumor of the neurolemma (myelin sheath) of a nerve fibre.
  • Acoustic neuroma - a tumor of the acoustic nerve
• Ganglioneuroma could be considered a type of neuroma, though it is not a nerve sheath tumor.

Non-neoplastic neuromas

In its most general sense, neuroma can be applied to any swelling of a nerve. Thus, there are a variety of usages that don't refer to neoplastic tumors.

• Traumatic neuroma follows different forms of nerve injury (often as a result of surgery). They occur at the end of injured nerve fibres as a form of ineffective, unregulated nerve regeneration; it occurs most commonly near a scar, either superficially (skin, subcutaneous fat) or deep (e.g., after a cholecystectomy). They are often very painful. It is also known as "pseudoneuroma".

• Morton's neuroma (a mononeuropathy of the foot) is another example of the older, more general usage of neuroma. Some prefer the term "Morton's metatarsalgia", thus avoiding the term neuroma and its association with tumors. ^[3]

References