Masses and Cysts
Background
Photograph of a benign cyst of the ankle.
The vast majority of lumps and bumps in the foot and ankle are completely benign. However, all masses should be assessed by an orthopaedic surgeon for potentially dangerous qualities (i.e. to ensure that the risk of a malignant/cancerous process is low).
The most common benign causes of soft tissue masses in the foot and ankle are:
Ganglion cyst
Giant cell tumor of tendon sheath
Lipoma
Plantar fibromatosis
Foreign body reaction / epidermal inclusion cyst
Rhematoid nodule
Gouty tophus
Mucoid cyst
Again, cancer in the foot and ankle is rare. However, cancers sometimes seen in the foot and ankle include osteosarcoma, Ewing’s sarcoma, chondrosarcoma, synovial cell sarcoma, epithelioid sarcoma, clear cell sarcoma, skin carcinoma, and melanoma. These should be ruled out by an orthopaedic surgeon.
Diagnosis
Patient undergoing an MRI of the foot and ankle. The head remains outside of the scanner to prevent claustrophobia.
Dr. Bohl will begin by asking questions about the qualities of your mass, including its duration, changes over time, and associated symptoms such as swelling or pain. He will then perform a physical examination to assess the size, location, compressibility, mobility, depth, and shape of the mass. X-rays will be obtained to examine for underlying arthritic processes and/or calcifications of the soft tissue.
In many cases when a benign processes is presumed, patients will have two options:
Option one is to observe. In this case, Dr. Bohl will schedule a follow-up appointment several months later and the mass can be assessed for changes in size or shape. If the mass is stable in size and shape and not causing symptoms, further observation is a very acceptable option.
Option two is to obtain an MRI to narrow the diagnosis. In this case, Dr. Bohl will write a prescription for this imaging study, and you can follow-up with him to discuss the MRI’s results, as well as nonsurgical and surgical options.
In the rare circumstance that Dr. Bohl suspects a mass is not benign, he will obtain the additional opinion of a musculoskeletal oncologist.
Nonsurgical Management
MRI of a benign soft tissue mass on the bottom of the foot between the first and second toes.
For many patients, the mass is not symptomatic or painful. Such patients may simply want reassurance that the mass is not dangerous. Dr. Bohl will be happy to provide them with an assessment, resources, and his recommendation.
For patients with presumed benign masses or cysts, observation—either with or without an initial MRI—is a very reasonable option. Dr. Bohl will typically recommend one or two formal follow-up appointments to ensure that the mass is not changing in size, shape, or quality over time.
For cysts, there are some medical providers who will offer aspiration, which means using a needle to remove the fluid within the mass, making the mass smaller. In general, Dr. Bohl recommends against this procedure, as rapid recurrence is extremely common and there is some associated risk.
Surgical Management
Dr. Bohl’s team will place your foot and ankle in a soft dressing after he has removed the mass or cyst. That dressing remains in place for two weeks, until the sutures are removed.
Many patients want a benign mass taken out, even if it is not causing symptoms. This is an extremely reasonable request. For such patients, Dr. Bohl will usually prescribe an MRI. The MRI assists in the final diagnosis and defines the borders of surgical resection, increasing the safety and precision of surgery. Dr. Bohl will usually ask you to obtain the MRI and then follow-up in person to simultaneously discuss the results and plan for surgery. If you have the MRI performed at a facility outside the Rush system, it is important that you bring both the images on the CD and the paper radiologist report.
For the vast majority of masses and cysts, surgical removal is a very minor procedure, taking less than thirty minutes to perform. Patients are discharged on the same day with a soft dressing and can walk on their leg immediately. Recovery is quick and easy.
Two weeks after surgery, Dr. Bohl asks you to come back to clinic to have your sutures removed. At that visit, Dr. Bohl will give you a copy of the pathology report for your permanent records, and discuss the pathologic diagnosis and any implications with you. For the vast majority of patients the diagnosis will simply be ganglion cyst or other benign soft tissue mass, and no further management will be necessary.