Adenocarcinoma is a medical term that means gland cell cancer. You might see this term in the results from a biopsy procedure to diagnose cancer. Or it may be included in your health record after surgery to remove cancer. If you wonder what adenocarcinoma means and what it says about your cancer, here is some information to help explain.

Adenocarcinoma is cancer that starts in gland cells, also called glandular cells. Gland cells are found all over the body. Gland cells help make the oil on the skin, the saliva in the mouth, and the mucus that helps food and waste move through the digestive system. Adenocarcinoma can start in any of the gland cells in the body. Most breast cancers, colon cancers, lung cancers and prostate cancers are adenocarcinomas.

Adenocarcinoma is a type of cancer. But there are different ways to describe cancers. Most people think about cancer in terms of where it happens in the body. Breast cancer starts in the breast. Colon cancer starts in the colon.

In addition to location, cancer type also can refer to the type of cell where the cancer starts. Adenocarcinoma starts in gland cells. Squamous cell carcinoma starts in thin, flat cells called squamous cells. Both adenocarcinoma and squamous cell carcinoma are carcinomas. Carcinoma is cancer that starts in the lining that covers much of the outside and inside surfaces of the body. This lining, called the epithelium, makes up the skin and the inside lining of many organs.

All adenocarcinomas are cancerous. Another term for cancerous is malignant. Malignant means that the cells can invade healthy tissue and spread to other parts of the body.

There also can be growths in the gland cells that aren't cancerous. A growth that isn't cancerous is called benign. Benign means the cells that form the growth can't invade healthy tissue and don't spread in the body. One example is an adenoma, which is a noncancerous growth of cells that starts in the gland cells.

Adenocarcinoma can happen in many places in the body.

Some cancers are more likely to be adenocarcinomas. Adenocarcinoma is the most common type of these cancers:

• Ampullary cancer.
• Breast cancer.
• Colon cancer.
• Endometrial cancer.
• Esophageal cancer.
• Gallbladder cancer.
• Kidney cancer.
• Lung cancer.
• Ovarian cancer.
• Pancreatic cancer.
• Prostate cancer.
• Rectal cancer.
• Stomach cancer.

Other cancers are less likely to be adenocarcinomas. These cancers can be adenocarcinoma, but it's not the most common type:

• Anal cancer.
• Appendix cancer.
• Bladder cancer.
• Cervical cancer.
• Small bowel cancer, also called small intestine cancer.
• Vaginal cancer.
• Vulvar cancer.

Adenocarcinomas can cause symptoms. Symptoms typically can't tell you whether a cancer is adenocarcinoma. Cancer symptoms depend more on the cancer's location than on what kind of cells the cancer is made of.

Bladder adenocarcinoma is a rare type of bladder cancer. Because it may start in gland cells that can make mucus, bladder adenocarcinoma might cause mucus in the urine. Other symptoms are similar to those in other bladder cancers, including:

• Blood in the urine.
• Having to urinate more often.
• Pain when urinating.

Colon adenocarcinoma is the most common type of cancer in the colon. Nearly all colon cancers are adenocarcinomas. Symptoms of colon cancer include:

• Blood in the stool.
• Constipation.
• Feeling very tired, which can happen if the cancer bleeds slowly and causes anemia.

Esophageal adenocarcinoma is the most common type of cancer in the esophagus in the United States. In other parts of the world, the most common type is squamous cell carcinoma. Symptoms of esophageal cancer include:

• Chest pain.
• Losing weight without trying.
• Trouble swallowing food.

Gastric adenocarcinoma is the most common type of stomach cancer. Symptoms of stomach cancer include:

• Heartburn.
• Nausea.
• Not feeling hungry when you might expect to feel hungry.

Kidney adenocarcinoma is more commonly called renal cell carcinoma. It's the most common type of kidney cancer. Symptoms of kidney cancer include:

• Blood in the urine.
• Losing weight without trying.
• Pain on the side or the back.

Lung adenocarcinoma is the most common type of lung cancer in the United States. It's considered a type of non-small cell lung cancer. Lung adenocarcinoma often grows on the outer edges of the lungs and might not be noticed at first. Symptoms of lung cancer include:

• A cough that never seems to go away or that keeps getting worse.
• Chest pain.
• Coughing up blood.

Pancreatic adenocarcinoma is the most common type of cancer in the pancreas. Nearly all pancreatic cancers are adenocarcinomas. Symptoms of pancreatic cancer include:

• Back pain.
• Losing weight without trying.
• Yellowing of the skin and the whites of the eyes.

While blood tests and imaging tests can detect cancer, these tests can't say whether the cancer is an adenocarcinoma. To know whether a cancer is adenocarcinoma, a sample of the cells must be removed from the body. The cells go to a lab for testing.

Tests and procedures that can get a sample of cells for testing to look for adenocarcinoma include:

• Cytology tests. Cytology tests involve collecting cells for testing. Sometimes these tests can find cancer cells that are adenocarcinoma. One example of a cytology test is cervical cytology, which also is called a Pap test or Pap smear.
• Biopsy procedures. A biopsy is a procedure to remove a sample of tissue for testing in a lab. A healthcare professional might get the tissue using a needle. Sometimes surgery is used to get the tissue for testing.

Healthcare professionals in the lab do tests on the cells to find out if the cells are adenocarcinoma. Testing in the lab is often directed by pathologists. Pathologists are doctors who do tests on blood and tissue samples to make a diagnosis. They put the results of their tests into a pathology report. The report goes to your healthcare team. The team can help you understand the results.

Tests might include looking at the cells with a microscope. Adenocarcinoma cells often look like gland cells. Professionals in the lab might decide the cells are adenocarcinoma by looking at them. Sometimes the cells look different from gland cells, so other tests are needed to make the diagnosis. Tests might look for any proteins the cells are making. Other tests might look for changes in the cells' DNA to make the diagnosis.

The pathology report might include other terms to describe the adenocarcinoma cells. Often these terms describe how the cells look. Examples include:

• Goblet cell adenocarcinoma. Goblet cell adenocarcinoma has cells that look like gland cells called goblet cells. Goblet cells, which are named for their shape, are most often found in the lining of the airways and the digestive system.
• Mucinous adenocarcinoma. Mucinous adenocarcinoma has cells that make a fluid called mucin. This type of cancer can happen in many places in the body.
• Signet ring adenocarcinoma. Signet ring adenocarcinoma has cells that are filled with fluid. Healthcare professionals say the cells look like signet rings. A signet ring is a ring worn on a finger that has a flat surface on the top. Signet ring adenocarcinoma is an aggressive type of cancer.

There are many ways of describing how the adenocarcinoma cells look. Your healthcare team can explain the terms that are used in your pathology report.

A pathology report also might include the cancer's grade. The grade tells the healthcare team about how quickly the cancer is growing. The grade also lets the healthcare team know if the cancer is an aggressive cancer that is likely to spread. A cancer's grade is different from the stage. The stage tells the healthcare team about the size of the cancer and whether it has spread.

There aren't specific grades for adenocarcinoma. A cancer's grade depends on where the cancer is in the body and how the cancer cells look when viewed with a microscope. There are different ways of grading different cancers.

A cancer's grade is often given as a number. The numbers depend on the kind of cancer. Prostate cancer grades go from 1 to 5. Colon cancer grades go from 1 to 4. Pancreatic cancer grades go from 1 to 3. A lower number means that cancer is growing slowly. A higher number means the cancer is growing quickly.

To decide on the grade, health professionals look at the cells with a microscope. They compare the cancer cells with healthy cells. Cancer cells that look a lot like healthy cells get a lower grade number. Cancer cells that look very different from healthy cells get a higher grade number.

• Low-grade cancer. A lower grade number means the cancer cells look similar to healthy cells. Low-grade cancers usually grow slowly and aren't likely to spread. Healthcare professionals also might call these well-differentiated cancers.
• Intermediate-grade cancer. The middle grade numbers mean the cancer cells look different from the healthy cells. They might have different shapes and start to look jumbled. Intermediate-grade cancers grow more quickly and are more likely to spread than low-grade cancers. Healthcare professionals also might call these moderately differentiated cancers.
• High-grade cancer. The higher grade numbers mean the cancer cells look very different from healthy cells. They may be so different that it's hard to tell what kind of cells they are. Healthcare professionals sometimes say these cancers are poorly differentiated or undifferentiated. They are more likely to grow quickly and more likely to spread. High-grade cancers are aggressive cancers.

There are different ways of stating the cancer's grade in a pathology report. For example, the grade of a prostate cancer is reported as the Gleason score and Gleason grade group.

The cancer's stage is a number that tells the healthcare team about the size of the cancer and whether the cancer has spread. There aren't specific stages for adenocarcinoma. The cancer's stage depends more on where the cancer is in the body.

Cancer stages typically go from 0 to 4. A lower number often means the cancer is small and only in one place. As the cancer grows and spreads to the lymph nodes or other parts of the body, the numbers go up. A stage 4 cancer often means the cancer has spread to other parts of the body. What the stages mean is different for each type of cancer.

Like other types of cancer, adenocarcinoma can spread. But not every adenocarcinoma will spread. Whether your cancer is likely to spread is based on many factors.

When cancer spreads, it's called metastatic cancer. Cancer cells can break away and spread through the blood or the lymphatic system to other parts of the body. Metastatic adenocarcinoma typically spreads to the lymph nodes first before going to other parts of the body.

When cancer spreads, it is named for the place where it started. For example, breast cancer that spreads to the lung isn't lung cancer. Instead, it's called metastatic breast cancer.

Healthcare professionals aren't sure exactly why some adenocarcinomas spread and others don't. It also isn't clear why some cancers often spread to certain organs and not to others.

Many treatments exist for adenocarcinoma. Your healthcare team typically chooses treatments based on where the cancer is in the body. Treatment options might include surgery to remove the cancer and radiation therapy to kill the cancer cells with powerful energy beams. Many kinds of medicines also can treat adenocarcinoma. Chemotherapy uses powerful medicines to kill cancer cells. Immunotherapy uses medicines and treatments that help the body's immune system fight the cancer cells.

Whether a cancer involves adenocarcinoma cells or other types of cells is one thing that healthcare professionals consider when thinking about prognosis. Many other factors can affect prognosis.

The cancer's location affects the prognosis. In lung cancer, adenocarcinoma has a better survival rate than other types of lung cancer. In small bowel cancer, adenocarcinoma has a worse survival rate than other types of cancer in the small intestine.

Factors that affect prognosis include:

• Where the adenocarcinoma is in the body. Cancers in some parts of the body are more likely to be found when they are small and are more likely to be cured.
• Whether the adenocarcinoma is invasive. An invasive cancer can spread. A noninvasive cancer, also called an in situ cancer, has little risk of spreading.
• Whether the adenocarcinoma is aggressive. A high-grade cancer is more likely to be an aggressive cancer that will spread.
• Whether the adenocarcinoma is advanced. An advanced cancer has grown large and may have spread to the lymph nodes or to other parts of the body. It's typically more difficult to cure.

If you're interested in knowing more about your prognosis, talk about it with your healthcare team. They can help you understand what your type of cancer means for your outlook.

April 16, 2025

Original article: https://www.mayoclinic.org/zh-hans/diseases-conditions/cancer/in-depth/adenocarcinoma/art-20580469