Q&A: A mass on the adrenal gland...what to do?

Q: I was having an abdominal CT scan for another reason and a mass was found on the adrenal gland on top of one of my kidneys. My doctors say it’s unlikely to be cancer, but they’re going to keep an eye on it. Shouldn’t a biopsy be done?

A: Fortunately, if a mass is found in one or both of the hormone-releasing adrenal glands, it’s usually not cancer and causes no other problems. However, an evaluation of the mass is typically necessary.

Adrenal masses are estimated to occur in 3% to 7% of older adults. About 95% of the time, they’re not cancerous. However, a small number of these non-cancerous adrenal masses can increase hormone levels and cause Cushing’s syndrome and health problems such as high blood pressure, low potassium, diabetes, and even increased risk of heart disease.

Distinguishing a potentially harmful mass from a harmless one can often be done with imaging, most commonly a CT scan targeted at assessing the mass. A cancerous mass will likely be larger in size and have an irregular shape. A noncancerous mass will likely have a smoother, rounder shape and is smaller in size. Excess hormone production — if present — can be documented using certain blood or urine tests.

Although imaging can provide very good information, it can’t provide a 100% distinction between a cancerous and noncancerous mass. Biopsy — which is often a go-to diagnostic test other tumors — is ineffective at making this distinction in most people with adrenal masses, and can be harmful. However, a biopsy may be helpful in people with a known cancer that may have spread to the adrenal gland.

In masses that are larger, have cancer- like characteristics or are having a harmful impact on hormone levels, surgical removal of the mass is likely to be discussed or recommended. Fortunately, the majority of smaller masses are non-cancerous and can be followed with repeat imaging.

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