A nodule is a small, solid, rounded mass or lump that can grow under the skin, within tissues, or in organs. Nodules may vary in size, texture, and location, and can be noncancerous or cancerous. They can develop as a result of inflammation, infection, or the growth of abnormal cells. Some common types of nodules include thyroid nodules, skin nodules, lung nodules, and prostate nodules. The characteristics, symptoms, and treatments of nodules depend on the type and cause of the condition.
