.The cells in a healthy individual normally grow, divide, age, die and are replaced. However, cells may divide too rapidly, or some old cells may fail to die in some cases. When this happens, an abnormal mass of solid tissues called a tumor is formed. A tumor can be classified as benign or malignant. A benign tumor is non-cancerous, does spread to other body parts, can be completely removed, not likely to recur, and not life-threatening. However, a malignant tumor is cancerous, can invade other parts of the body, if removed it can still return, and it is life-threatening. But a benign tumor can become cancerous if left untreated. So, regularly monitor any abnormal growth in consultation with a doctor.  Even though benign tumors are not life threatening some brain tumors can cause inflammation and pressure on sensitive tissues surrounding them.

A tumor can occur anywhere in the body. Also, tumors vary in size and will cause swelling or lump as they grow bigger. Unlike most malignant tumors, blood cancer does not usually take a solid form. An example of blood cancer is leukemia where abnormal white blood cells outnumber normal white blood cells. Other types of blood cancers include myeloma, lymphoma, myeloproliferative neoplasms, and myelodysplastic syndromes

Naming of Tumors

A tumor is also called neoplasm. Benign tumors (or benign neoplasm) have different names depending on where they develop:

  • Adenoma: It is a benign tumor which grows on or in a gland (e.g., pituitary gland) or organ (e.g., liver).
  • Fibroid (or fibroma): This is a non-cancerous tumor which affects fibrous tissues in the body. Fibrous tissue is a dense connective tissue in the dermis, tendons, and ligaments. Mostly commonly, fibroid occur in the skin, mouth, foot, and uterus (called uterine fibroid).
  • Chondroma: It is a benign neoplasm which occurs in the cartilage, a flexible connective tissue in the body.
  • Hemangioma: It is a benign tumor derived from blood vessels. It mostly occurs on the skin of babies but can also be found on internal organs such as brain, liver, or colon.
  • Lipoma: It is a benign fatty tumor derived from fat cells and grows just below the skin. It’s the most common type of benign tumor. 
  • Myoma: This is a form of benign tumor which affects the muscles cells. There are 2 main types of myoma; leiomyomas which occur in smooth muscles and rhabdomyomas which occur in striated muscles. Leiomyomas are more common in the uterus and often referred to as uterine fibroids.
  • Osteoma: This is a non-cancerous tumor which grows from bone. Here, a new piece of bone grows on another bone, typically the skull. This is referred to as homoplastic osteoma. In heteroplastic osteoma, a new piece of bone grows but on other tissues and not on other bones. Osteoma is most common in children and young adults.
  • Lymphangioma (or lymphatic malformations): This non-cancerous tumor results from malfunctions of the lymphatic system and forms fluid-filled cyst on the skin or mucous membranes. 
  • Meningioma: It affects the central nervous system and forms on the membranes (meninges) surrounding the brain and spinal cord. Although benign, a meningioma can grow to be become life-threatening as it presses on the brain and spinal cord. 
  • Nuroma: It is a benign growth of nerve tissues mostly found between the third and fourth toes although it can occur anywhere in the body.  A nuroma is a very painful condition often referred to as pinched nerves, or nerve tumor. 
  • Skin tumor: Skin tumors can be benign or malignant. Examples of benign skin tumors include cherry angioma, sebaceous hyperplasia, seborrheic keratoses, dermatofibromas and acrochordons (also called skin tags).

Like benign tumors, malignant tumors are named based on their site of origin, the type of cells they are made up of, or based on the tissue structure of the tumor. 

What is a premalignant tumor

Benign tumors are non-cancerous but some have the potential to become cancerous. Therefore, a benign tumor which has not been treated or removed needed to be monitored closely especially if the cells continue to change or divide uncontrollably. 

Examples of benign tumors with the potential to become cancerous include:

  • Hyperplasia. It is an increase in cell production in a normal tissue or organ. The cells formed are normal-looking cells.
  • Atypia. This involves an increase in cell production and the cells appear slightly abnormal.
  • Metaplasia. Here, a differentiated cell type is transformed into another differentiated cell type such that cells look normal but aren’t the type of cells usually found in this area of the body.
  • Dysplasia. It is the abnormal development of a cell within tissues or organs. Cells appear abnormal, are reproducing faster than normal, and aren’t arranged normally.
  • Carcinoma in situ. Cells are extremely abnormal but haven’t yet invaded nearby tissue. This is sometimes called “stage 0” cancer.

How to treat benign and malignant tumors

Most benign tumors don’t cause a problem and don’t need to be treated or removed. However, if symptoms or complications arise due to a benign tumor, then it can be treated or removed through surgery. Once removed, a benign tumor hardly grows back.

Unlike benign tumors which are treated mainly through surgery, treatment of malignant tumors may involve seven different treatment methods namely: Chemotherapy, Targeted therapy, Surgery, radiotherapy, Hormone therapy, immunotherapy, and clinical trials. After treatment, a malignant tumor can come back.