When Lung Cancer Spreads to the Adrenal Glands

If you've been told that your lung cancer (or another cancer) has spread to your adrenal glands (adrenal metastasis) you may be feeling confused. Unlike the spread of cancer to other areas, such as the liver, spread to the adrenal glands isn't talked about as frequently. That said, adrenal metastases are very common with lung cancer.

While the diagnosis of adrenal metastasis would rightly cause anyone concern, it is important to note that the condition has a better prognosis than other sites of metastases, especially if it occurs on the same side of the body as the original (primary) tumor.

The adrenal glands are small triangular shaped glands that are located on top of each kidney. These endocrine glands are responsible for secreting hormones, including "stress hormones" such as cortisol, epinephrine (adrenaline), and norepinephrine. 

Nearly any cancer can spread to the adrenal glands, but some tumors are more likely than others to metastasize to this region.

Other common cancers that spread to this region include kidney cancer, melanoma, breast cancer, colon cancer, and lymphoma.

Up to 40% of people with lung cancer will develop adrenal metastases at some time, and in 10% of people with non-small cell lung cancer, the disease spreads to both adrenal glands. These metastases are present in 2% to 3% of people at the time of diagnosis, and on rare occasions are the first sign of lung cancer.

Most of the time when cancer spreads to the adrenal glands there aren't any symptoms. In fact, in one study only 5% of people with adrenal metastases had symptoms. People are most often only aware of these metastases due to radiology studies such as a CT scan, MRI, or PET scan.

When symptoms are present, they may include:

• Back pain (in the mid-back region).
• Abdominal pain.
• Bleeding into the abdomen (hemorrhage).
• Adrenal insufficiency (Addison's disease): Symptoms of Addison's disease may include weakness, low blood pressure (hypotension), low blood sugar (hypoglycemia), a low sodium level in the blood (hyponatremia), and a high potassium level (hyperkalemia).

If you have a scan suspicious for adrenal metastases, you won't necessarily need any further evaluation, especially if you have metastases to other regions of your body. In some cases, your doctor may wish to be certain that a mass in your adrenal gland is due to metastatic cancer, and recommend a CT-guided biopsy.

The treatment recommended for adrenal metastases can vary depending on several factors. For all people supportive care is important. In people with symptoms such as hemorrhage, treatments such as surgery may be necessary to control symptoms. In some people, treatment with the goal of curing cancer may be a possibility.

Whether or not you and your doctor decide upon further treatment of your cancer or your adrenal metastases, caring for your symptoms remains paramount. People with cancer deserve good pain management and control of other symptoms related to cancer.

Adrenal metastases rarely cause symptoms. If a metastasis is bleeding (hemorrhaging) or is at high risk of bleeding, surgery to remove the tumor and adrenal gland (adrenalectomy) may be recommended. If the metastasis has resulted in adrenal insufficiency, treatment with steroids may be needed. If back pain or abdominal pain occurs, this should be treated.

Treating stage 4 lung cancer may include chemotherapy, targeted therapies, immunotherapy, and/or radiation therapy. Some people also participate in clinical trials studying new drugs and procedures. The addition of targeted therapies and immunotherapy have changed the face of advanced lung cancer for many people in recent years.

An example is ALK positive lung cancer. A 2018 study found that, with appropriate treatment, the median survival of people with stage 4 disease was 6.8 years, even if they had brain metastases.

Immunotherapy, when effective, has sometimes even resulted in a "durable response," holding lung cancer in check for a lengthy period of time. Since the first drug in this category was only approved in 2015, we have yet to know if the remissions we sometimes see will last, or what the long-term outcomes may be.

For people with an isolated adrenal metastasis, treatment may potentially result in long-term survival. Options include:

• Surgery: Both open and laparoscopic adrenalectomy (removal of an adrenal gland) may be done with a curative intent for some people.
• SBRT: If surgery isn't possible, studies suggest that stereotactic body radiotherapy (SBRT) may be effective and well tolerated. SBRT involves using a high dose of radiation to a small area, and sometimes has results similar to surgery. In a 2018 study, local treatment of lung cancer adrenal metastases with SBRT resulted in overall survival rates at 6 months, 1 year, and 2 years of 85.8%, 58.1%, and 54%.
• Ablation: Image-guided percutaneous ablation is yet another option. A 2018 study found that, although survival was poorer for those with non-small cell lung cancer who underwent the procedure than with some other cancers, image-guided percutaneous ablation of adrenal metastases may extend local progression-free survival as well as overall survival. In the study, the average overall survival (for all tumor types combined) at 1, 3, and 5 years was 82, 44, and 34% following the procedure.

Without treatment, the median survival following a diagnosis of adrenal metastases was only around three months. With that said, recent studies evaluating the aggressive surgical treatment of adrenal metastases have been encouraging. In addition, studies done in the past do not reflect the many new treatments for lung cancer that have been approved in just the past few years.

The researchers further reported that people with contralateral adrenal metastasis (cancer occurring on the opposite side of the body) had a five-year survival of zero.

The answer to why certain adrenal metastases have a better prognosis may be in how cancer spreads through the body. Broadly speaking, cancer spreads in three distinct ways:

• As a tumor invades nearby tissue
• As cancer cells break off and travel through the lymphatic system
• As cancer cells break off and travel through the bloodstream

Ipsilateral (same-sided) adrenal metastases are believed to be associated with the lymphatic system, while contralateral (opposite-sided) adrenal metastases are believed related to the bloodstream.

By contrast, when cancer cells enter the bloodstream, they circulate again and again throughout the body without stopgaps. Doing so typically results in more widespread disease as multiple organs are exposed to the circulating cancer cells.

Contralateral adrenal metastasis is more likely to occur via the bloodstream given that this is the most obvious path between a primary lung tumor and a contralateral adrenal gland.

The prognosis with metastatic lung cancer is not what we would wish. That said, of all sites of metastases, adrenal metastases often have a better prognosis (and as noted, the prognosis is even better if the involved adrenal gland is on the same side of the body as the lung cancer).

In addition, the treatment options and survival rates for advanced lung cancer are slowly improving, especially when targeted therapies for genetic mutations or immunotherapy drugs can be used to treat the tumor.

If you've been diagnosed with stage 4 lung cancer and adrenal metastases, take time to learn about your cancer. Participating in the lung cancer community online is very helpful. Newer treatments are improving survival rates, but the treatment of lung cancer is changing so rapidly that is hard for anyone to stay on top of the latest findings.

You may also wish to consider a second opinion at one of the larger National Cancer Institute-designated cancer centers where oncologists who specialize in lung cancer have access to the latest research and clinical trials available.

Whatever the stage of your cancer, take an active part in your care and be your own advocate. Self-advocacy not only reduces anxiety and helps you feel more in control of your disease, but may improve outcomes as well. Keep in mind that the local treatment of "oligometastases" (a term used to describe a situation in which only a few metastases are present) is very new, and despite encouraging studies, not all physicians have had the opportunity to experience these treatments with their patients, or the potential benefits. Lung cancer treatment is changing so rapidly that it is challenging even for lung cancer specialists to keep up with all of the changes, and changes that are occurring across disciplines such as oncology, thoracic surgery, and radiation oncology.