Michael Coyer, DPM, AACFAS
Foot & Ankle Surgeon from Orange County, California
Associate Member of the American College of Foot and Ankle Surgeons

"I've got this lump on my foot—what could it be?" As a foot and ankle surgeon, I am asked this question quite frequently. I always explain that because bumps on feet can signal both serious and non-serious conditions, it is always best to have all lumps and bumps properly examined by a foot and ankle surgeon.   

Bumps on feet can vary in size, from that of a pea to the size of a golf ball. They can also vary in location, from the arch of the foot to the ankle area or elsewhere. They may or may not hurt or cause changes in daily activity. But a lump found in the foot has a possibility of being cancerous, and for this reason, must not be ignored.

The most common type of lump found in the foot is a soft-tissue mass called a ganglionic cyst. This soft, fluid-filled sac is a benign (noncancerous) bump found on the tendons and joints. A ganglionic cyst can be caused by a leaking of jelly-like fluid from the "capsule" surrounding a joint or tendon and may be located on the top of the foot, near an ankle joint or even on the side of the foot. The cyst will not go away on its own and tends to return, even after being drained. The best way to keep a ganglionic cyst from recurring is to have it surgically removed by a foot and ankle surgeon.

Another common type of lump found in feet are plantar fibromas. These often painless, benign masses are fibrous, hard nodules found within the ligament of the foot and are especially common in the arch area on the bottom of the foot. These bumps tend to be less than an inch in diameter but can get larger over time. Nonsurgical treatments, such as steroid injections, physical therapy or orthotic devices, may help relieve any discomfort but will not make the fibroma disappear. Surgery to remove the mass is an option for patients who continue to experience pain following nonsurgical approaches.

For foot bumps that are suspected of being cancerous, we perform a biopsy on the area. A tissue sample from the biopsy is then sent to a lab, and advanced imaging or an MRI may be used to gauge more information about the mass. If it is indeed cancer, the foot and ankle surgeon will perform surgery to remove the mass in tandem with an oncologist for cancer treatment.

Remember, foot bumps do not tend to go away on their own. The sooner we are able to properly evaluate the bump, the sooner a patient can have peace of mind and move forward with treatment, whether surgical or nonsurgical, so they may resume everyday activity.

For more information on foot bumps or to find a foot and ankle surgeon near you, visit FootHealthFacts.org, the American College of Foot and Ankle Surgeon's patient education website.

Michael Coyer, DPM, AACFAS, a foot and ankle surgeon with offices in Orange County, California, is board certified in both foot surgery and reconstructive rearfoot and ankle surgery by the American Board of Foot and Ankle Surgery. He is an Associate Member of the American College of Foot and Ankle Surgeons.