Carcinoma of unknown primary

Overview

Carcinoma of unknown primary is a diagnosis healthcare professionals give when they can't find where a cancer started. A carcinoma of unknown primary is an advanced cancer that has spread in the body.

Most often, health professionals detect a cancer when it grows in the place where it started. The place where a cancer started growing is called the primary cancer. Sometimes health professionals first detect a cancer when it spreads. When cancer spreads it's called metastatic cancer.

In carcinoma of unknown primary, healthcare professionals find the metastatic cancer. But they can't find the primary cancer. Carcinoma of unknown primary also is called occult primary cancer.

Healthcare teams often use the kind of primary cancer you have to help decide on the treatment. If you're found to have carcinoma of unknown primary, this piece of information is missing. Your healthcare team will work to find out what kind of cancer you have.

Symptoms

Signs and symptoms of carcinoma of unknown primary include:

• A cough that won't go away.
• Feeling very tired.
• Fever that doesn't have a clear cause.
• Losing weight without trying.
• Nausea and vomiting.
• Pain in one part of the body.
• Swelling of the belly.
• Swollen lymph nodes.

When to see a doctor

Make an appointment with a doctor or other healthcare professional if you have any symptoms that worry you.

Causes

The cause of carcinoma of unknown primary often isn't known. Healthcare professionals use this diagnosis when they find signs of cancer that has spread but can't find where the cancer started. The place where a cancer started growing is called the primary cancer.

Carcinoma of unknown primary can happen if:

• The primary cancer is too small to detect with imaging tests.
• The primary cancer was killed by the body's immune system.
• The primary cancer was removed in an operation for another condition.

Risk factors

The risk of carcinoma of unknown primary might be related to:

• Older age. This type of cancer happens most often in people older than 60.
• Family history of cancer. If a close relative had carcinoma of unknown primary, you may have an increased risk of this cancer. There also is some evidence that carcinoma of unknown primary happens more often in people with a family history of cancer that affects the lungs, kidneys or colon.
• Smoking cigarettes. People who smoke cigarettes may have a higher risk of carcinoma of unknown primary.

Living with carcinoma of unknown primary?

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