Where and How Stomach Cancer Spreads

Although cancer often starts localized to one area or region in your body, some cancers — like stomach cancer (gastric cancer) — can spread to other areas during later stages. This action of spreading beyond its place of origin to another location is called metastasis or metastatic cancer.

“The problem with gastric cancer is there is a delay in presentation and symptoms, so it’s often caught during later stages,” says general surgeon Emanuele Lo Menzo, MD. “Once the cancer becomes symptomatic, the likelihood it has spread is higher.”

How far it spreads and how quickly it happens depends on a variety of factors. But there is a general path that stomach cancer tends to follow if it continues to grow or becomes resistant to treatment.

Dr. Lo Menzo explains the route stomach cancer typically takes when it metastasizes and whether there’s anything you can do to stop the spread during the course of treatment.

How stomach cancer spreads

Stomach cancer usually starts in the lining of your stomach before spreading to your lymph nodes, liver and beyond. But why is this the route for metastasis?

As stomach cancer cells get deeper into the lining of your stomach, they can begin to invade your lymphatic system.

Your lymphatic system is like your body’s drainage pipes. One of its functions involves collecting excess fluid from your body’s tissues and returning it back into your bloodstream.

“Your lymphatic system has filtering stations called lymph nodes, and that’s where the cancer gets filtered and comes into contact with your blood vessels,” explains Dr. Lo Menzo. “The blood supply of your stomach is drained by the liver, which is the biggest filter in your body. So, that’s why your lymph nodes and your liver are often the first places stomach cancer spreads.”

Once it metastasizes to your liver and lymph nodes, stomach cancer cells can spread to other areas of your intestines. And it can spread to the ovaries in women and people assigned female at birth (AFAB). It can even spread farther in very late stages to other organs like your lungs.

Signs stomach cancer has metastasized

Studies have found that nearly half of all gastric cancer cases metastasize or spread to other areas of the body, with the liver being the most common destination, followed by the peritoneum, lungs and bones.

But it’s hard to know whether cancer has spread to other locations outside of the stomach unless a healthcare provider catches it in diagnostic testing or you experience a wider range of symptoms (like difficulty breathing).

“In very late stages, you can develop excess fluid inside the abdomen called ascites,” shares Dr. Lo Menzo. “This can occur because of excessive production of the cancer in the peritoneal cavity or because of decreased filtration from the liver caused by the spreading of cancer cells.”

Is there a way to stop stomach cancer from spreading?

Treatments like surgery, chemotherapy and radiation are the only way to stop the spread of stomach cancer. How you utilize those treatments and the order in which you receive them depends on how extensive the cancer has become and how your body responds to treatment.

“For stomach cancers that are very early and localized in an area of the stomach, sometimes, we can use endoscopic treatments,” explains Dr. Lo Menzo. “In later stages when endoscopic treatments are not possible, we tend to use some combination of chemotherapy and/or radiation therapy followed by gastrectomy to remove part or all of the stomach.”

Once the cancer has spread to other locations like your liver or lungs, your healthcare providers will need to make other interventions to try to treat the cancer in those specific areas.

“Although surgery is an option in some cases, that is not the only curative intervention because we have to target the cancer cells that are now no longer by the original tumor,” he adds.

Relying on chemotherapy and radiation therapy even before surgery can sometimes kill off any of the stomach cancer cells that have already migrated away from the original tumor.

“Most likely, someone will need additional chemotherapy after surgery,” Dr. Lo Menzo stresses.

All of this is to say, treatment options vary and so do their outcomes. Along the way, it’s important that you continue to take care of yourself in other areas of your life. Often, people will make certain lifestyle modifications to help reduce the severity of their symptoms as they go through treatment, and to help improve their quality of life. However you choose to treat the spread of cancer is up to you and your extensive multidisciplinary team of healthcare providers.