Pigmented villonodular synovitis (PVNS) is one type of mass that poses a challenge to podiatric surgeons due to its unique nature and high rates of recurrence. Accordingly, these authors discuss surgical excision and adjunct radiation therapy to treat this mass in the foot and ankle of a 31-year-old patient.
A 31-year-old male presented to our clinic for evaluation of painful soft tissue masses to his left foot and ankle. He noted that he had the masses for approximately four months. The patient complained of a “knot” on his lateral foot and ankle, which was becoming larger in size and increasingly painful. Due to this increased pain and stiffness in the ankle joint, he was unable to work his usual construction job. The patient had an unremarkable past medical history and did not take any medications. He had no drug allergies. The patient confirmed alcohol and marijuana usage, but denied tobacco use.
Upon physical examination, there were two soft tissue masses present to the left lower extremity, one at the lateral foot over the calcaneocuboid joint and at the anterior lateral ankle joint. The masses measured 3.5 x 3.0 cm and 2.0 x 1.5 cm respectively, and were firm and painful to palpation. The patient had palpable dorsalis pedis and posterior tibial pulses graded at 2/4. Gross sensation was intact to the digits of the left foot via light touch. Muscle mass and strength were within normal limits to the lower extremities.
Initial workup consisted of plain film radiographs that were unremarkable. Subsequent magnetic resonance imaging (MRI) showed an irregular, ill-defined enhancing soft tissue mass, which appeared to protrude from the anterior aspect of the tibiotalar joint and the dorsal aspect of the calcaneocuboid articulation. Findings were non-specific and somewhat atypical but did raise the possibility of a synovial proliferative process such as pigmented villonodular synovitis.
Due to high rates of recurrence associated with pigmented villonodular synovitis, we consulted radiation oncology for possible adjunct treatment. The team determined that, upon confirmation of pigmented villonodular synovitis, we would pursue a two-pronged approach to treatment in order to provide the patient with the best likely long-term outcome. This planned approach would include excision of the masses with adjunct radiation therapy.
After obtaining appropriate informed consent, we proceeded with the surgery. With the patient under general anesthesia and in a lateral decubitus position, we made a hockey stick incision over the masses, starting at the anterolateral ankle and extending distally and anteriorly over the calcaneocuboid joint. Carrying the incision sharply and bluntly to the level of the soft tissue masses, we noted the masses to be well-encapsulated and multilobulated in appearance with a brown homogenous color. After excising the masses, we sent them to pathology for evaluation. We then flushed and closed the incision per standard technique.
The pathology report later showed the masses to be giant cell tumors consistent with pigmented villonodular synovitis. As a result, after completion of surgery, the patient underwent five weeks of adjunct radiation therapy with a total of 20 sessions overseen by the radiation oncology department. The patient recovered well and returned to normal activity without complications.
What You Should Know About Pigmented Villonodular Synovitis
Pigmented villonodular synovitis is a benign, locally aggressive disorder of joints, bursae and tendon sheaths.1-3 There is no consensus regarding the exact cause of the disease.1,3 The overall incidence includes two to 10 percent of cases that occur in the foot and ankle.1,3 Patients often present with swelling and discomfort.3 Pigmented villonodular synovitis has both local and diffuse forms.2 The localized form tends to present as a pedunculated nodule within a joint whereas the diffuse form tends to infiltrate the synovial lining.2 Diagnosis often requires a combination of clinical, radiological and histological correlations.3
Treatment with surgical excision alone tends to have high rates of recurrence.1,2 One study examining the recurrence of PVNS in individuals who underwent surgical resection without adjuvant radiotherapy found a high recurrence rate of 40 percent.2 In a separate study, Schnirring-Judge and Lin found recurrence rates as high as 45 percent despite surgical intervention.1 Radiation therapy has shown to be effective in preventing recurrence but poses risks including fibrosis, swelling, wound complications and malignant transformation.2
When deciding how to treat pigmented villonodular synovitis, it is important to determine whether the benefit of reducing recurrence will outweigh the risk of complications for each individual patient.2 As a result, adjunct radiation therapy is something to consider on a case by case basis. Our patient is an example of an individual who suffered from this relatively rare condition and successfully completed surgical excision coupled with radiation therapy. More research is necessary moving forward to further delineate the benefits of adjunct radiation therapy with respect to pigmented villonodular synovitis when weighed against potential risks of this treatment modality.
Dr. Block is a second-year resident at the Department of Veterans Affairs Captain James A. Lovell Federal Health Care Center in North Chicago.
Dr. Youkhana is a second-year resident at Department of Veterans Affairs Captain James A. Lovell Federal Health Care Center in North Chicago.
Dr. Budz is a Fellow of the American College of Foot and Ankle Surgeons, and is in private practice in Orland Park, Ill. He is the Chair of Podiatry at Mount Sinai Hospital in Chicago.
Dr. Wu is the Dean and Professor of Surgery at the Dr. William M. Scholl College of Podiatric Medicine, and Professor of Stem Cell and Regenerative Medicine at the School of Graduate Medical Sciences at the Rosalind Franklin University of Medicine and Science in Chicago. She is also the Director of the Center for Lower Extremity Ambulatory Research (CLEAR) in Chicago.
1. Schnirring-Judge M, Lin B. Pigmented villonodular synovitis of the ankle—radiation therapy as a primary treatment to reduce recurrence: a case report with 8-year follow-up. J Foot Ankle Surg. 2011;50(1):108-116.
2. Sung K, Ko K. Surgical outcomes after excision of pigmented villonodular synovitis localized to the ankle and hindfoot without adjuvant therapy. J Foot Ankle Surg. 2015;54(2):160-163.
3. Sharma H, Jane M, Reid R. pigmented villonodular synovitis of the foot and ankle: forty years of experience from the Scottish Bone Tumor Registry. J Foot Ankle Surg. 2006;45(5):329-336.