What is the Difference Between Benign and Malignant

The main difference between benign and malignant is that benign is the term for tumours that do not invade surrounding tissues whereas malignant is the term for tumours that invade surrounding tissues. Therefore, the cells in the benign tumours are not cancerous while the cells in the malignant tumours are cancerous.

Benign and malignant are two types of tumours which can occur in the body. Generally, a tumour refers to an abnormal growth of cells. These cells have overgrown to produce a lump.

Key Areas Covered

1. What is Benign
     – Definition, Spreading, Treatment
2. What is Malignant
     – Definition, Spreading, Treatment
3. What are the Similarities Between Benign and Malignant
     – Outline of Common features
4. What is the Difference Between Benign and Malignant
     – Comparison of Key Differences

Key Terms

Benign, Cancerous, Invasion, Malignant, Recurrence, Spreading, Treatment, Tumors

What is Benign

Benign is a term that describes the tumours that do not invade the surrounding tissues. One of the most prominent hallmarks of being cancerous is the ability of the cells to penetrate the basal membrane, which surrounds a particular tissue. Since the cells in benign tumours cannot penetrate the basal membrane, either to invade or spread to the surrounding tissues, these cells are not cancerous. Accordingly, benign tumours are less worrisome and can easily be removable with a surgery. Listed below are some of the common types of benign tumours.

• Adenomas in the epithelial tissue, which covers the organs and glands
• Meningiomas in the brain and the spinal cord
• Fibromas/fibroids in the connective tissue of any organ
• Papillomas in the skin, breast, cervix, and mucous membranes
• Lipomas in fat cells
• Nevi in moles
• Myomas in the muscle tissue
• Hemangiomas in blood vessels and the skin
• Neuromas in the nerves
• Osteochondromas in bones

Figure 1: Normal Epidermis and Dermis with a Benign Intradermal Nevus

However, some benign tumours can grow very large, which can be dangerous. They can enclose the space of the skull, press on the vital organs or block channels. Moreover, some benign tumours can become malignant including the adenomas in the colon. They are considered as precancerous.

What is Malignant

Malignant is a term that describes tumours that have the ability to invade surrounding tissues by penetrating the basal membrane. Therefore, the cells in these tumours are cancerous. The migration of the cancerous cells from a malignant tumour occurs either through the blood or lymphatic system. Metastasis is the term that refers to this type of spreading to the other tissues of the body. After metastasis, the cancerous cells are difficult to remove from the body with surgery. Therefore, either radiation therapy or chemotherapy has to be employed in treating them.

Figure 2: Benign vs Malignant

Listed below are different types of malignant tumours.

• Carcinoma that starts in the skin or tissues in internal organs
• Sarcoma that begins in the connective tissues of the body including bone, cartilage, muscle, fat, and blood vessels
• Leukaemia is a malignancy that begins in the blood-forming tissue including bone marrow
• Lymphoma and multiple myeloma in cells of the immune system
• Central nervous system cancers that occur in the spinal cord or brain tissue

Similarities Between Benign and Malignant

• Benign and malignant are two terms that describe different types of tumours.
• Both refer to abnormal growth of cells that form lumps.
• Also, the cells in both types of tumours trigger systemic effect by secreting substances.
• Besides, biopsy tests are used in identifying the difference between benign and malignant tumours.

Difference Between Benign and Malignant

Definition

Benign describes an abnormal growth that does not invade surrounding tissue or spread to other parts of the body. Malignant describes an abnormal growth that can invade and destroy nearby tissue and that may spread (metastasize) to other parts of the body. Therefore, these definitions explain the main difference between benign and malignant.

Growth Rate

Moreover, benign tumours have a slow growth rate while malignant tumours have a fast growth rate.

Cellular Appearance

An important difference between benign and malignant is that most cells in benign tumours are normal while the cells in malignant tumours have abnormal DNA and chromosomes, which make the nucleus larger and darker.

Cancerousness

The cells in the benign tumours are not cancerous while the cells in the malignant tumours are cancerous. Hence, this is another important difference between benign and malignant.

Local Invasion

Moreover, benign tumours do not invade the tissues around them while malignant tumours invade the tissues around them. As said before, this is the main difference between benign and malignant tumours. 

Spreading at Distance

Furthermore, benign tumours do not spread to the other parts of the body while malignant tumours spread to the other parts of the body either through the bloodstream or lymphatic tissue.

Removability

Another difference between benign and malignant tumours is that benign tumours are easy to remove while malignant tumours are difficult to remove.

Recurrence

Recurrence is also a major difference between benign and malignant tumours. Benign tumours have less chance to recur while malignant tumours are more likely to recur.

Secretions

Besides, while benign cells secrete hormones including benign pheochromocytomas, malignant cells secrete substances, which cause fatigue and weight loss.

Treatments

Benign tumours can be treated with surgery while malignant tumours can be treated with chemotherapy, radiation therapy or immunotherapy treatments.

Conclusion

In conclusion, benign tumours are the abnormal growth of cells that do not invade the surrounding tissues. These tumours have a slow growth rate and it is possible to remove them by surgery, completely removing the tumour. On the other hand, malignant tumours are the type of tumours that invade the surrounding tissues. Therefore, they are cancerous and are difficult to remove. Moreover, they have a greater chance to recur. Therefore, the main difference between benign and malignant is the ability of a tumour to invade the surrounding tissues to become cancerous.

Reference:

1. “Benign Tumors.” WebMD, WebMD, Available Here
2. “What Is Malignant Cancer?” WebMD, WebMD, Available Here

Image Courtesy:

1. “Normal Epidermis and Dermis with Intradermal Nevus 10x” By Kilbad – Own work (Public Domain) via Commons Wikimedia 
2. “Types of tumor cells” By Manu5 – http://www.scientificanimations.com/wiki-images/ (CC BY-SA 4.0) via Commons Wikimedia