HPOA is a group of symptoms that include inflammation of the bones and joints in your wrists and ankles, and clubbing of the fingers and toes.
What it is
In cancer, HPOA can be caused by substances released by the tumour. Or it may be caused by substances the body makes because it is reacting to the tumour.
Looking at the meaning of each word on its own can help to understand what this syndrome is:
- hypertrophic means an enlargement or overgrowth of a body organ
- pulmonary means the lungs
- osteoarthropathy is a disease of bones and joints
HPOA is a rare syndrome, so there is very little information about it. Most information is about individual case studies reported in medical journals and text books, which can be difficult to understand.
Who might get it
People with lung disease can get HPOA. It affects about 5 out of every 100 people (5%) with cancer of the windpipe (bronchus) or lung, and up to 50% with pleural mesothelioma.
In cancer, it is most common in people with non small cell lung cancer. We don't really know why some people with lung cancer get it and others don't.
HPOA most often causes inflammation of the bones and joints in your wrists and ankles. Sometimes this shows up on bone scans or X-rays. Ankles and wrists can become swollen and inflamed, causing a lot of pain and difficulty with movement.
Another common symptom of HPOA is a condition known as clubbing. This means the fingers and toes broaden at the ends, and the nails curve and thicken. Clubbing of the fingers is a common symptom of lung and heart conditions.
No one knows exactly why clubbing develops. It may be because there is not enough oxygen in the blood.
Your doctor is most likely to give you painkillers such as non steroidal anti inflammatory drugs.
There have been some reports that drugs called bisphosphonates can help to relieve pain in people with HPOA. Bisphosphonates help to slow down the destruction of bone. But we don't yet know how well these drugs work as treatment for HPOA symptoms.