Lumps and masses in the foot or around the ankle are rarely dangerous tumors. Only about one in one thousand are malignant tumors capable of spreading to other parts of the body. More common are bursas, ganglion cysts, inclusion cysts, fibromas or lipomas. Ganglion cysts are best thought of as containing leaks of lubricating fluid of tendons or joints. While they are not generally harmful, they can be painful. Bursas are small sacs of fluid that the body produces to cushion prominent bones or protect tendons from irritation. On occasion, they can become inflamed and irritated themselves. Inclusion cysts form when the body walls off a foreign body. These can often form from splinters and pet hairs.
There are many other kinds of masses. It is difficult to definitely diagnose a mass without microscopic examination. Certain types of masses occur in certain areas and this can be a clue to the diagnosis, but to be sure about the mass, excision is often necessary. MRI can sometimes be used, but the diagnosis is often inconclusive.
What You Can Do
- If you have a mass, have it examined.
What Your Doctor May Do
- Aspirate or drain the mass if it appears to be fluid-filled.
- Inject the mass with a steroid, which may shrink it.
- Order an MRI.
- Recommend and perform excision. The mass can then be examined by a pathologist and a diagnosis can be definitely made.