Adenocarcinoma: Definition, Locations, Diagnosis, Treatment, and Therapy Options

It is a subset of a broader category of epithelial tumors known as carcinomas.

Adenocarcinomas are malignant epithelial tumors with glandular differentiation or mucin production by tumor cells. Their benign counterparts are known as adenomas.

Carcinomas are the most common form of human tumors (approximately 80% of all non-cutaneous malignancies), and adenocarcinomas are the most common form of carcinomas.

Carcinomas can arise in virtually any organ that contains glandular or secretory epithelium, and the most common sites include the lung, kidney, gastrointestinal tract, breast, and prostate.

In some organs, such as the colon-rectum, breast, and kidney, almost all carcinomas are adenocarcinomas, while in other organs, such as the lung, only a part of carcinomas are adenocarcinomas.

As with other epithelial malignancies, adenocarcinomas are often preceded by histopathologically identifiable preneoplastic lesions.

Molecular changes can generally be detected during the long preneoplastic process and may be present in histologically normal-appearing epithelium.


Their molecular pathogenesis varies considerably because adenocarcinomas can arise from multiple diverse structures and organs.

Locations of an adenocarcinoma

Adenocarcinoma is cancer that forms in mucus-secreting glands throughout the body.

The glands make the body’s fluids stay moist and work well.

When adenocarcinoma cells in the glands that line organs grow out of control, they can spread to other places and damage healthy tissue.

The disease can develop in many different places, but it is more common in the following types of cancer:

Colon and rectum

Adenocarcinoma is the most common type of colon cancer. It begins as a small polyp or growth, which is generally harmless at first but can turn into cancer.

The disease can also start in the rectum, the part of the large intestine where waste leftover from digested food, called feces, is flushed out of your body.


Most breast cancers are adenocarcinomas. They begin in the glands of the breasts, where milk is produced.


This is the tube that carries food from the mouth to the stomach. Adenocarcinoma usually begins in the mucous glands that line the lower part of the esophagus.

Cancer that forms in the epithelial cells of the esophagus is known as adenocarcinoma. This is the most common type of esophageal cancer.


Adenocarcinoma constitutes approximately 40% of lung cancers.

It is most often found on the outside of the lungs and grows more slowly than other types of lung cancer.

In general, this type of cancer is obtained if the person is an active or passive smoker or used to be.


This is an organ in the back of the belly, behind the stomach, and is in charge of producing hormones and enzymes that help digest food.

About 85% of exocrine pancreatic cancer tumors are caused by adenocarcinoma, representing the most common type. These tumors begin in the ducts of this organ.


This is a gland that men have, and that is just below the bladder and helps to produce part of the fluid that protects the sperm cells.

Adenocarcinoma usually begins in the cells that make these fluids.

Cancer that forms in the prostate gland is generally an adenocarcinoma, accounting for 99 percent of all prostate cancers.

An adenocarcinoma can also develop in other parts of the body.

Diagnosis of adenocarcinoma

Diagnostic tests vary according to the location of cancer. When diagnosing adenocarcinoma, the following tests may be done:


It is the removal of a sample of abnormal tissue in the body, which will be examined under a microscope to determine the existence of cancer cells.

A biopsy can be used to find out if cancer started at the biopsy site or elsewhere in the body.

Computed tomography

This x-ray procedure uses a computer to take detailed, three-dimensional images of abnormal tissue in the body.

CT scans are also done during treatment to see if cancer responds to treatment.

Magnetic resonance imaging

MRIs use radiofrequency waves to create detailed cross-sectional images of different body parts.

Adenocarcinoma Treatment and Therapy Options

Treatment for adenocarcinoma varies depending on where it grows in the body but may include:


Adenocarcinoma is often treated by surgically removing the cancerous glandular tissue and some surrounding tissues.

Minimally invasive surgical methods can help reduce healing time and reduce the risk of infection after surgery.


This adenocarcinoma treatment option is generally combined with surgery and chemotherapy.

Advanced radiation therapies use image guidance before and during treatment to treat adenocarcinoma tumors as part of a process designed to preserve healthy tissues and surrounding organs.


Chemotherapy treats adenocarcinoma with drugs designed to kill cancer cells throughout the body or in a specific area.

Some chemotherapy drugs can kill both cancer and healthy cells. Other newer drugs can target only cancer cells.

Cancer treatment can have side effects. The patient may feel very tired or feel like they need to vomit.

The doctor can suggest ways to manage these problems, prescribing drugs that fight nausea.

Talking with family and friends about how the patient feels and raising concerns and fears is helpful while receiving treatment and can be a great source of support.