Definition & Overview

A benign neoplasm is an abnormal but non-cancerous growth that may occur in different parts of the body. The word “neoplasm” came from the Greek word “neo”, which means new, and “plasma”, which means “formation or creation”, thus pertaining to the abnormal growth of new tissue. Neoplasms are more commonly referred to as tumours, but since they are classified as benign, they do not cause cancer, unlike pre-cancerous or malignant tumours. Neoplasms or tumours also go by the names “nodules” or “mass”, depending on their size. Nodules are neoplasms that are less than 20 mm in size, whereas a mass is at least 20 mm in diameter.

Unlike malignant tumours, benign ones grow at a slower rate and are not known to metastasize or spread to the tissues surrounding them. When they form, they take the characteristics of the tissue they originated from and may form either alone or in clusters. Since they do not cause immediate danger to life, they oftentimes do not require immediate treatment, but are still closely observed as they can sometimes grow big enough to cause problems in the proper functioning of the body. The two main dangers to watch out for when there is a benign tumour are when the neoplasia grows into a mass and when they grow in small areas of the body where they can cause an obstruction. In such cases, they may also be life-threatening and may thus require treatment.

Cause of Condition

Benign neoplasms are known to be caused by several possible factors, such as:

  • Exposure to radiation and other environmental toxins
  • Poor diet
  • Genetics or genetic mutations
  • Stress
  • Infection
  • Injury
  • Trauma

The actual growth of benign neoplasms is triggered by cell proliferation, cell migration, or cell death. Regardless of the underlying cause, the abnormal cell behaviour and tissue growth is a sign that there is a problem with specific genes, especially the tumour suppressor genes. The following are the genetic causes that have been linked with the growth of benign tumours:

  • PTEN hamartoma syndrome or hamartomatous disorders involving the PTEN or tumour suppressor gene

  • Familial adenomatous polyposis or mutations involving the APC tumour suppressor gene

  • Von Hippel-Lindau disease or an inherited condition that causes mutations involving the Von Hippel-Lindau tumour suppressor gene

  • Tuberous sclerosis complex or mutations involving the TSC1 and TSC2 genes which are responsible for the production of hamartin and tuberin proteins that may cause excessive protein production leading to abnormal cell growth

Abnormal growths in different types of tissue also affect the specific type of neoplasia that forms. The most common types of benign tumours include:

  • Lipoma – Benign neoplasms originating from fat cells and most commonly occur in the neck, shoulders, arms, and back; they are often inherited but may also result from a previous injury. They grow slow and are soft, round, and movable

  • Adenoma – Benign neoplasms originating from the glands or tissues in the glands, the most common of which is a tumour in the thyroid gland

  • Haemangioma – Benign neoplasms originating from a blood vessel build up

  • Fibroma – Benign neoplasms originating from connective tissue or fibres

Although most neoplasms are characterized by an abnormal tissue proliferation, some may also manifest in other forms, such as sebaceous cysts, glandular inflammation, hematomas, hamartomas, choristomas, necrotic tissue, granulomas, and keloids.

Key Symptoms

Benign neoplasms can act in very diverse manners; while they are commonly asymptomatic, they may also cause some symptoms depending on where they are located, the tissue they originate from, and their underlying cause.

The most common symptoms, when they do occur, may arise from:

  • Compressed tissue
  • Compressed organs
  • Blocked ducts
  • Ischaemia or reduced blood flow
  • Nerve damage
  • Tissue death or necrosis
  • Abnormal hormone production

These may cause a wide variety of symptoms including nerve pain, shortness of breath, dizziness, abnormal bleeding, seizures, and compromised bodily functions. Hormonal abnormalities may also result in the following diseases:

  • Pituitary adenomas
  • Cushings disease
  • Anemia

Benign tumours may also manifest themselves as external growths that may cause a cosmetic concern to the patient.

Who to See and Types of Treatments Available

In the absence of symptoms, many benign neoplasms are detected during routine physical exams or imaging scans. However, if some symptoms are felt, patients may go to their family physician or internal medicine doctor for a diagnosis. Since they are not cancerous, benign neoplasms do not need the expertise of an oncologist unless the tumour is causing health problems in which case, the treatment is usually done by a multidisciplinary team composed of a number of specialists.

The first step in the treatment of a benign neoplasm is a period of watchful waiting, where the doctors monitor the tumour’s growth to see whether they will cause problems. If they do cause problems, the available treatment options include:

  • Radiotherapy – Many benign tumours do not respond to radiotherapy but this can also work, especially for intracranial tumours and hemangiomas.

  • Radiosurgery – Radiosurgery is performed by targeting the tumour using high-energy radiation beams, with the goal of killing the abnormal cell growths. This can be done in a single session, depending on the size of the tumour, followed by a quick recovery period.

  • Sclerotherapy – This is a form of treatment that aims to shrink blood vessels to cut off the blood supply to restrict the growth of the tumour.

  • Surgery – Benign tumours that are causing problems, often due to their location or size, can be surgically removed. Surgical removal often requires general anaesthesia.

  • Medication – Patients may also be given medications to prevent or manage the symptoms they are experiencing. Some medications aim to relieve pain, treat headaches (as in the case of benign brain tumours), prevent vomiting and seizures, or reduce inflammation.

Chemotherapy is rarely used for benign neoplasms as non-cancerous tumours are not known to respond to it. Also, in most cases, given the low risk or threat posed by the benign growth, many patients are not willing to experience the side effects commonly linked to chemotherapy, which include hair loss, skin redness, nausea, and exhaustion.

For skin neoplasms, there is a wide range of special treatments available such as laser excision, cryotherapy, curettage, dermabrasion, electrodessication, or chemical peels. There are also some topical medications that can be used to shrink the tumour.


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