The information on this page was reviewed and approved by
Maurie Markman, MD, President, Medicine & Science at CTCA.

This page was updated on May 24, 2021.


Adenocarcinoma may occur almost anywhere in the body, starting in glands that line the insides of the organs. Adenocarcinoma forms in glandular epithelial cells, which secrete mucus, digestive juices or other fluids. It is a subtype of carcinoma, the most common form of cancer, and typically forms solid tumors.

Your glands help your body function properly and keep organs moist. If glandular cells begin growing out of control, spurred by mutations that occur in the body’s DNA replication process, they may form tumors. Some tumors in glandular cells are not cancerous. They’re called adenomas. The malignant tumors are adenocarcinomas, which overtake healthy tissue inside an organ and may spread to other parts of the body.

Adenocarcinomas are generally first seen as a thickened, plaque-like white mucous membrane, according to the National Cancer Institute. They often spread easily through the soft tissue where they occur.

Adenocarcinoma cancers

Many organs have glandular cells. Adenocarcinoma is often identified by its specific type, such as exocrine cancer in the pancreas, invasive ductal carcinoma in the breast or endometrial cancer in the uterus. Adenocarcinoma is most prevalent in the following diseases:

  • Lung cancer: Non-small cell lung cancer accounts for 80 percent of lung cancers, and adenocarcinoma is the most common type.
  • Prostate cancer: Cancer that forms in the prostate gland is typically an adenocarcinoma, which accounts for 99 percent of all prostate cancers. Read about the symptoms of prostate cancer.
  • Pancreatic cancer: Exocrine pancreatic cancer tumors are called adenocarcinomas. They form in the pancreas ducts.
  • Esophageal cancer: Cancer that forms in the glandular cells of the esophagus is known as adenocarcinoma. This is the most common type of esophageal cancer.
  • Colorectal cancer: Cancer that develops in the intestinal gland cells that line the inside of the colon and/or rectum is an adenocarcinoma. It makes up 95 percent of colon and rectal cancers.
  • Breast cancer: The most common form of breast cancer, invasive ductal carcinoma, is an adenocarcinoma.
  • Stomach cancer: More than 90 percent of stomach cancer (gastric cancer) cases are adenocarcinomas, either intestinal or diffuse.

It’s possible for adenocarcinoma to appear in the brain, usually from cancer that has metastasized from other areas of the body. Adenocarcinoma may also develop elsewhere in the body.

With so many different types of cancer under the heading of adenocarcinoma—and the metastases that are possible—there are many different risk factors and symptoms, depending on the specific disease. Smoking is one risk factor that appears to apply to all adenocarcinomas.

Diagnosing adenocarcinoma

Because adenocarcinoma may develop in so many different areas of the body, the type of diagnostic tests used also vary.

Breast cancer is frequently found in its early stages during mammogram screenings. Prostate cancers are often detected through a prostate-specific antigen (PSA) blood test or a digital rectal exam (DRE). A colonoscopy may be used for diagnosing colon cancer, while bronchoscopy may be used to detect adenocarcinoma of the lung.

In general, the types of tests that are performed may include:

Biopsy: This procedure is used to remove a sample of abnormal tissue from the body. A pathologist will then examine the tissue under a microscope to see whether cancer is present. A biopsy may also be used to determine whether a cancer originated at the site of the biopsy or if it’s metastatic, meaning it developed in another part of the body.

CT scan: A computed tomography scan is an imaging procedure that takes detailed, three-dimensional X-ray pictures of abnormal tissue in the body. CT scans may also be used to determine how adenocarcinoma is responding to treatment.

MRI: Magnetic resonance imaging uses radiofrequency waves to create detailed cross-sectional images of different parts of the body.

Blood tests: These lab tests are used to detect specific chemicals in the blood that may be related to different adenocarcinomas.

At Cancer Treatment Centers of America® (CTCA), our oncology diagnostic team is led by oncologists and other physicians trained in a wide variety of medical specialties, including radiology, pathology, genetics and advanced genomic testing. They use sophisticated tests and procedures to measure the stage and progression of disease and identify the tumor’s type, size and location.

Treatment options

Treatment for adenocarcinoma also varies depending on where it grows in the body. Treatments may include:

Surgery: Often the first line of treatment for adenocarcinoma, surgery is used to remove the cancerous glandular tissue and some surrounding tissue. If possible, minimally invasive surgical procedures may be used to help reduce healing time and the risk of post-surgical infection.

Chemotherapy: Chemotherapy uses drugs to kill cancer cells. Chemo drugs may be used throughout the body or in a specific area.

Radiation therapy: Often used in combination with surgery and/or chemotherapy, advanced radiation therapies use image guidance before and during treatment to target adenocarcinoma tumors and spare healthy tissues and surrounding organs.

Targeted therapy: Unlike chemotherapy, which kills healthy and cancerous cells, this treatment targets cancer cells directly. The therapy is designed to attack genetic features that regulate cells’ growth and division.

Immunotherapy: Rather than attack cancer cells directly, immunotherapy alerts the body’s immune system to the presence of the abnormal cells. That, in turn, triggers the body’s own immune response to attack the cancer.