Adenoma is a type of non-cancerous tumor or benign that may affect various organs. It is derived from the word “adeno” meaning 'pertaining to a gland'.

Every cell in the body has a tightly regulated system that dictates when it needs to grow, mature and eventually die off. Tumors and cancers occur when cells lose this control and divide and proliferate indiscriminately.

What’s the difference between a benign tumor and a cancer?

The basic difference between a benign tumor and a cancer is its slower growth and lower capacity to spread. In other words adenomas are much less aggressive in terms of growth than adenocarcinomas.

Where do adenomas originate?

An adenoma is a benign tumor originating in glandular tissue. The tissues affected are part of a larger tissue category known as epithelial tissues. Epithelial tissues line skin, glands, cavities of organs etc. This epithelium comes from the ectoderm, endoderm and mesoderm in the fetus.
Adenoma cells do not necessarily need to be part of a gland but may possess secretory properties.

Can adenomas become cancerous?

Adenomas are generally benign or non cancerous but carry the potential to become adenocarcinomas which are malignant or cancerous.

As benign growths they can grow in size to press upon the surrounding vital structures and leading to severe consequences.

Paraneoplastic syndromes

Large adenomas in vital hormone producing organs raise the hormones the organ produces leading to serious complications called paraneoplastic syndromes.

What organs are affected by adenomas?

Adenomas may affect various organs including:-

Colon

Colons are the most common organs that are affected by adenomas. There may be detected on colonoscopy. A regular surveillance of colonic adenomas and preferable removal of these tumors is advised as they have a very high potential to become colon cancers.

Pituitary gland

These are seen as incidental findings in many individuals and generally respond well to surgical removal of the tumor. The commonest type is called prolactinoma. These are seen more commonly among women. Hormone therapies and therapy with Bromocriptine is advised.

Thyroid gland

Adenomas of thyroids present as thyroid nodules. Surgery may be needed to remove them if they are secreting excess hormones.

Breasts

Breasts may be affected by fibroadenomas. These commonly affect young women and need to be biopsied to rule out cancer. Surgical removal is the best possible therapy.

Adrenal gland

These adenomas are quite common and rarely cancerous. They are usually small and in some cases may secrete excess of adrenal hormones like Cortisol leading to Cushing’s syndrome.

They may also secrete excess aldosterone leading to Conn’s syndrome. If these adenomas produce excess male sex hormones or androgens, they may cause hyperandrogenism.

Kidneys

Kidney adenomas affect the kidney tubules and may become cancerous.

Rarer adenomas

Rarer adenomas include those affecting the liver, appendix or the lungs.

Further Reading

• All Adenoma Content
• Adenoma Histopathology

Written by

Dr. Ananya Mandal

Dr. Ananya Mandal is a doctor by profession, lecturer by vocation and a medical writer by passion. She specialized in Clinical Pharmacology after her bachelor's (MBBS). For her, health communication is not just writing complicated reviews for professionals but making medical knowledge understandable and available to the general public as well.