Long-term Outcomes of Diffuse or Recurrent Tenosynovial Giant Cell Tumor Treated with Postoperative External Beam Radiation Therapy.

PURPOSE: Tenosynovial giant cell tumor (TGCT) is a rare proliferative disorder of synovial membrane that previously was known as pigmented villonodular synovitis. Primary treatment involves surgical resection; however, complete removal of all disease involvement is difficult to achieve. Radiation may be useful to reduce the risk of recurrence. We report and update our institutional experience treating diffuse and recurrent TGCT with postsurgical external beam radiation therapy. METHODS AND MATERIALS: We performed a retrospective chart review of 30 patients with TGCT from 2003 to 2019 treated with radiation therapy. Each patient was evaluated for demographics, radiation treatment parameters, surgical management, complications, and outcome. RESULTS: With mean follow-up of 82 months (range, 3-211), 24 patients (80%) who underwent surgery followed by radiation therapy did not experience any further relapse, and all 30 patients achieved local control (100%) with additional salvage therapy after radiation therapy. The most common site of disease was the knee (n = 22, 73%), followed by the ankle (n = 5, 16%) and the hand (n = 3, 10%). Seven patients (24%) presented at time of initial diagnosis and 23 (76%) presented with recurrent disease after surgical resection, with an average of 2.6 surgical procedures before radiation therapy. After resection, 18 of 30 patients (67%) demonstrated residual TGCT by imaging. The median radiation therapy dose delivered was 36 Gy (range, 34-36 Gy) in 1.8 to 2.5 Gy/fractions for 4 weeks. In the assessment of posttreatment joint function, 26 sites (86%) exhibited excellent or good function, 2 (7%) fair, and 2 poor (7%) as determined by our scoring system. There were no cases of radiation-associated malignancy. CONCLUSIONS: Among patients with diffuse or recurrent TGCT, postsurgical external beam radiation therapy provided excellent local control and good functional status, with minimal treatment-related complications. Postsurgical radiation therapy is a well-tolerated noninvasive treatment that should be considered after maximal cytoreductive resection to prevent disease progression and recurrence.

Clinical outcomes of endoscopic synovectomy with adjuvant radiotherapy of pigmented villonodular synovitis of the hip: a case series of single center.

BACKGROUND: Though radiotherapy has been widely used for knee pigmented villonodular synovitis (PVNS), there is few literatures about radiotherapy for the treatment of PVNS hip. Thus, the purpose of this study was to analyze the clinical outcomes of endoscopic synovectomy with/without radiotherapy postoperatively of PVNS hip. METHODS: We performed a retrospective study of patients who underwent endoscopy in our hospital from November 2010 to January 2021. Inclusion criteria was patients with magnetic resonance image (MRI) signs, endoscopic findings and/or histological evidence of PVNS. Exclusion criteria was patients lost follow-up. All patients underwent synovectomy endoscopically and were divided into two groups depending on receiving postoperative radiotherapy or not. The primary outcome measurements were the recurrence of PVNS, receiving revision, and/or converting to total hip arthroplasty (THA). The secondary outcome measurements were the patient-reported outcome (PRO) collected at pre- and post-operation, which consist of Hip Outcome Score Activities of Daily Living (HOS-ADL), modified Harris Hip Score (mHHS), International Hip Outcome Tool-12 (IHOT-12), Non-arthritic Hip Scale (NAHS), and visual analog scale (VAS). RESULTS: In a case series of 16 patients (8 cases of male, 50%), 4 (25%) cases were localized type and 12 (75%) cases were diffuse type. The average follow-up was 44.8 ± 38.2 months (range,3 to 110). 8 (50%) cases (6 diffuse cases and 2 localized cases) received radiotherapy postoperatively, and the rest (6 diffuse cases and 2 localized cases) received endoscopic treatment alone. At the latest follow-up, 3 (18.75%) cases (2 diffuse cases and 1 localized case) who did not receive radiotherapy converted to arthroplasty. The preoperative HOS-ADL, mHHS, IHOT-12, NAHS, VAS scores of remaining 13 patients were 63.1 ± 19.1 (range,32.0 to 98.8), 54.8 ± 20.1 (range, 10.0 to 77.0), 50.9 ± 15.4 (range, 31.0 to 76.6),51.6 ± 15.9 (range, 20.0 to 84.4), 6.0 ± 1.4 (range,4.0 to 8.0) points, respectively. The latest HOS-ADL, mHHS, IHOT-12, NAHS, VAS scores of the 13 patients were 79.7 ± 10.8 (range, 58.0 to 97.6), 78.6 ± 9.1 (range,55.0 to 87.0), 74.7 ± 9.7 (range, 55.6 to 91.0), 78.9 ± 18.7 (range,20.0 to 92.5), 3.1 ± 1.2 (range,2.0 to 6.0) points respectively. CONCLUSION: Endoscopic synovectomy can achieve satisfactory PRO in PVNS hip patients. Besides, postoperative adjuvant radiotherapy can achieve higher hip survivability than synovectomy alone in this present study.

Recurrence of pigmented villonodular synovitis of the knee: A case report with review of literature on the risk factors causing recurrence.

RATIONALE: Pigmented villonodular synovitis is a rare disease which may involve any joints. It has localized and diffuse forms, and the latter is more aggressive with a higher recurrence rate. Different treatments are applied to each form of the disease, but there is no standard surgical procedure or any consensus on whether adjuvant therapy should be used. Many factors may lead to recurrence of the disease; however, there is no reliable way to predict the recurrence. PATIENT CONCERNS: A 21-year-old female patient presented with a one-year history of progressive pain of the right knee. DIAGNOSES: Pigmented villonodular synovitis. INTERVENTIONS: We performed an anterior approach arthroscopic synovectomy and a posterior approach open synovectomy in the popliteal fossa, but the patient declined to take radiotherapy as a post-surgical adjuvant therapy. Then, she received a repeat arthroscopic synovectomy 20 months later because of the recurrent lesions, and a radiotherapy was performed 6 weeks after the second surgery. OUTCOMES: There were no abnormal signs in the right knee on magnetic resonance imaging scanning 6 months after the second surgery. The range of motion of her right knee was normal. LESSONS: Pigmented villonodular synovitis is a rare disease which may involve any joints. Surgical resection plus adjuvant therapy is recommended for patients with risk factors of recurrence.

The results of 394 consecutive cases of knee joint radiation synovectomy (radiosynoviorthesis) using 90Y.

OBJECTIVE: The aim of this study was to assess the treatment results of 90Y radiation synovectomy for chronic exudative synovitis of knee joints. METHODS: The retrospective data consist of 394 consecutive knee radiation synovectomies performed using 6 mCi (222 MBq) of 90Y. The assessment included 3-point custom pain and joint mobility scale, evaluation of joint's circumference, binary joint's temperature evaluation, patellar ballottement test, indications for puncture and its volume in applicable cases. 21 cases had to be forfeited due to missing data regarding follow-up. RESULTS: The final analysis of 373 treatment procedures performed in 253 patients yielded following results-at 6 months after treatment, 80.9% of the patients reported at least partial pain relief (including 33.3% with complete pain relief), which increased to 86.7% at one year. The pain intensity decreased over time, however, the outcomes were worse in older patients. The probability of pain recurrence was 15% at 6 months, and 28% at one year. It was highest in post-traumatic synovitis, and lowest in pigmented villonodular synovitis. The circumference of the treated knee joints decreased over the course of follow-up, however, the decrease was significantly lower in older patients. The fraction of patients with full knee joint mobility increased from 34.6 to 40.6% at 6 months and 49.2% at one year. The percentage of patients that required articular puncture decreased from 62.8% at baseline to about 35.6% at 6 months, and 32.8% at one year. Positive patellar ballottement was found in 68.5% before treatment and remained at about 40-50% during the course of follow-up. The increased temperature of the joint was reported in 51.2% at baseline and decreased to 33% at 6 months and 28.3% at one year. CONCLUSIONS: (1) Radiation synovectomy is a safe and effective method of treatment in patients with exudative synovitis, however, the pain recurrence rate is significantly higher in post-traumatic exudative synovitis compared to pigmented villonodular, undifferentiated, and rheumatoid arthritis. (2) Our results suggest that older patients have worse treatment results with radiation synovectomy compared to younger patients.

The effects of radiosynoviorthesis in pigmented villonodular synovitis of the knee.

INTRODUCTION: Tenosynovial giant-cell tumor also known as pigmented villonodular synovitis (PVS) is a benign but aggressive synovial proliferative disease most often affecting the knee joint. The mainstay of therapy is surgical resection. Due to a high rate of local recurrence, radiosynoviorthesis (RSO) is used as an adjuvant method in many cases. The aim of this study was to compare local recurrence (LR) rates after surgical synovectomy with and without adjuvant RSO. MATERIALS AND METHODS: From 1996 to 2014, 37 surgical interventions were performed in 32 patients with diffuse pigmented villonodular synovitis of the knee. All patients underwent open synovectomy. Adjuvant radiosynoviorthesis (RSO) was applied in 26 cases, the control group consists of 11 cases without RSO. RESULTS: 9 (24%) lesions recurred within a median of 19 months after surgery. Of those 9 recurrences, 3 (17%) were seen in primary disease, 6 (32%) in already recurring cases (n.s.). In 26 RSO treated patients 6 (23%) recurred, in 11 patients of the control group, 3 (27%) recurred (n.s.). CONCLUSIONS: RSO is effective in PVS as also shown in some smaller reports in the literature. But surgery is still the mainstay of therapy. RSO is not a method of compensating for an insufficient surgical approach, but it may reduce the high rate of LR in patients with large and even recurrent diffuse forms of the disease.

Inconclusive benefit of adjuvant 90Yttrium hydroxyapatite to radiosynovectomy for diffuse-type tenosynovial giant-cell tumour of the knee.

Aims: Intra-articular 90Yttrium (90Y) is an adjunct to surgical treatment by synovectomy for patients with diffuse-type tenosynovial giant-cell tumour (dtTGCT) of the knee, with variable success rates. Clinical information is, however, sparse and its value remains unclear. We investigated the long-term outcome of patients who underwent synovectomy with and without adjuvant treatment with 90Yttrium. Patients and Methods: All patients with dtTGCT of the knee who underwent synovectomy between 1991 and 2014 were included in the study. Group A patients underwent synovectomy and an intra-articular injection of 90Yttrium between six and eight weeks after surgery. Group B patients underwent surgery alone. Results: There were 34 patients in group A and 22 in group B. Recurrence of dtTGCT was identified by MRI, which was undertaken in patients with further symptoms. At a mean follow-up of 7.3 years (2.5 to 25.4), there was residual disease in 15 patients in group A and 11 in group B (p < 0.363). The mean Musculoskeletal Tumor Society (MSTS) score at final follow-up was 85% and 83%, respectively (p < 0.91). Conclusion: There were no significant differences in outcome between patients treated surgically for dtTGCT of the knee with or without an adjuvant intra-articular injection of 90Yttrium. We were unable to provide conclusive evidence of any benefits derived from the adjuvant treatment. Cite this article: Bone Joint J 2018;100-B:984-8.

Necessity of adjuvant postoperative radiotherapy for diffuse pigmented villonodular synovitis of the knee: A case report and literature review.

RATIONALE: Pigmented villonodular synovitis (PVNS) is an idiopathic, proliferative disorder lesion of synovial tissue, which is regarded as a benign disease, but has a local invasion. Up to now, these are no consensus about the etiology and pathogenesis of PVNS. Because of the lack of typical clinical features, misdiagnosis and delayed diagnosis are not uncommon, magnetic resonance imaging (MRI) can assist diagnosis and histopathological examination is recognized as the gold standard for the final diagnosis. Because this disease is so rare, there is no standard treatment. Surgical resection of the lesion is considered the preferred treatment, but postoperative recurrence is a problem that cannot be ignored. Postoperative radiotherapy is necessary, especially for patients with diffuse PVNS of the knee. PATIENT CONCERNS: A 27-year-old female teacher presented with 3 years chronic pain of the right knee, and progressive swelling aggravated for 1 week. The range of motion of the knee was limited. DIAGNOSES: Clinical and laboratory examination failed to provide definitive diagnosis. Imaging can assist in diagnosis, and pathology is the gold standard. Erythrocyte sedimentation rate (ESR), antihemolytic streptococcus O (ASO), and rheumatoid factors (RF) were all negative. Joint puncture revealed giant cell tumor of the synovial membrane. PVNS was confirmed by postoperative pathology. The characteristic T2 weighted low signal of MRI suggests the recurrence of PVNS. INTERVENTIONS: The patient underwent 2 stages of treatment: open synovectomy was performed in the first place and postoperative external radiotherapy was not considered. After 2 years of disease-free remission, she was diagnosed with a recurrence of the disease by MRI. Further, arthroscopic total synovectomy of the right knee was performed and external beam radiotherapy was carried out after the operation. OUTCOMES: Up to now, the patient was followed up for 3 years without any sign of recurrence. LESSONS: Adjuvant postoperative radiotherapy can improve the local control rate, it is a reliable treatment method for diffused PVNS.

Results and recurrence of pigmented villonodular synovitis of the ankle: does diffuse PVNS with extra-articular extension tend to recur more often?

PURPOSE: The aim of this study was to provide the outcomes and to analyze the recurrence of Pigmented Villonodular Synovitis (PVNS) of the ankle joint treated by surgical synovectomy. METHODS: Thirty-one PVNS cases of the ankle, including 5 localized PVNS cases and 26 diffuse PVNS cases, were treated in our institute between 2004 and 2015. The median age was 35 (range 18-63) years. The 5 localized PVNS cases were treated with partial synovectomy (group I); 10 diffuse PVNS cases limited to intra-articular synovium received arthroscopic comprehensive synovectomy (group II); and 16 cases with diffuse PVNS spreading to extra-articular tendon sheaths underwent combined arthroscopic and open synovectomy (group III). Adjuvant radiotherapy was provided in groups II and III. The American Orthopaedic Foot and Ankle Society (AOFAS) score and subjective grading of procedure were used to evaluate the results. RESULTS: Twenty-seven patients were followed with a median of 54 (range 15-108) months. In the three groups, the average AOFAS score improved from 75 (in all three groups) points preoperatively to 100 (group I), 97 (group II), and 90 points (group III) postoperatively. The rate of good-to-excellent result was 100% in group I and II and 73.3% in group III. Only in group III, recurrence occurred in five cases. CONCLUSIONS: Diffuse PVNS of the ankle can be successfully managed with surgical synovectomy and adjuvant radiotherapy. Radiotherapy is not needed for localized PVNS. The recurrence rate in PVNS patients with extra-articular extension is higher. LEVEL OF EVIDENCE: IV.

Organ-specific radiation-induced cancer risk estimates due to radiotherapy for benign pigmented villonodular synovitis.

Pigmented villonodular synovitis (PVNS) is a benign disease affecting synovial membranes of young and middle-aged adults. The aggressive treatment of this disorder often involves external-beam irradiation. This study was motivated by the lack of data relating to the radiation exposure of healthy tissues and radiotherapy-induced cancer risk. Monte Carlo methodology was employed to simulate a patient's irradiation for PVNS in the knee and hip joints with a 6 MV photon beam. The average radiation dose received by twenty-two out-of-field critical organs of the human body was calculated. These calculations were combined with the appropriate organ-, age- and gender-specific risk coefficients of the BEIR-VII model to estimate the lifetime probability of cancer development. The risk for carcinogenesis to colon, which was partly included in the treatment fields used for hip irradiation, was determined with a non-linear mechanistic model and differential dose-volume histograms obtained by CT-based 3D radiotherapy planning. Risk assessments were compared with the nominal lifetime intrinsic risk (LIR) values. Knee irradiation to 36 Gy resulted in out-of-field organ doses of 0.2-24.6 mGy. The corresponding range from hip radiotherapy was 1.2-455.1 mGy whereas the organ equivalent dose for the colon was up to 654.9 mGy. The organ-specific cancer risks from knee irradiation for PVNS were found to be inconsequential since they were at least 161.5 times lower than the LIRs irrespective of the patient's age and gender. The bladder and colon cancer risk from radiotherapy in the hip joint was up to 3.2 and 6.6 times smaller than the LIR, respectively. These cancer risks may slightly elevate the nominal incidence rates and they should not be ignored during the patient's treatment planning and follow-up. The probabilities for developing any other solid tumor were more than 20 times lower than the LIRs and, therefore, they may be considered as small.

The effect of surgical synovectomy and radiotherapy on the rate of recurrence of pigmented villonodular synovitis of the knee: an individual patient meta-analysis.

Pigmented villonodular synovitis (PVNS) is a rare proliferative process of the synovium which most commonly affects the knee and occurs in either a localised (LPVNS) or a diffuse form (DPVNS). The effect of different methods of surgical synovectomy and adjuvant radiotherapy on the rate of recurrence is unclear. We conducted a systematic review and identified 35 observational studies in English which reported the use of surgical synovectomy to treat PVNS of the knee. A meta-analysis included 630 patients, 137 (21.8%) of whom had a recurrence after synovectomy. For patients with DPVNS, low-quality evidence found that the rate of recurrence was reduced by both open synovectomy (odds ration (OR) = 0.47; 95% CI 0.25 to 0.90; p = 0.024) and combined open and arthroscopic synovectomy (OR = 0.19, 95% CI = 0.06 to 0.58; p = 0.003) compared with arthroscopic surgery. Very low-quality evidence found that the rate of recurrence of DPVNS was reduced by peri-operative radiotherapy (OR = 0.31, 95% CI 0.14 to 0.70; p = 0.01). Very low-quality evidence suggested that the rate of recurrence of LPVNS was not related to the surgical approach. This meta-analysis suggests that open synovectomy or synovectomy combined with peri-operative radiotherapy for DPVNS is associated with a reduced rate of recurrence. Large long-term prospective multicentre observational studies, with a focus on both rate of recurrence and function, are required to confirm these findings.

External beam radiation therapy for orthopaedic pathology.

External beam radiation therapy is essential in the management of a wide spectrum of musculoskeletal conditions, both benign and malignant, including bony and soft-tissue sarcomas, metastatic tumors, pigmented villonodular synovitis, and heterotopic ossification. Radiation therapy, in combination with surgery, helps reduce the functional loss from cancer resections. Although the field of radiation therapy is firmly rooted in physics and radiation biology, its indications and delivery methods are rapidly evolving. External beam radiation therapy mainly comes in the form of four sources of radiotherapy: protons, photons, electrons, and neutrons. Each type of energy has a unique role in treating various pathologies; however, these energy types also have their own distinctive limitations and morbidities.

Postoperative radiotherapy for diffuse pigmented villonodular synovitis of the temporomandibular joint.

BACKGROUND: Pigmented villonodular synovitis (PVNS) is a rare/benign condition of the synovial joint lining. It most commonly presents in the knee but has also been reported to occur in the temporomandibular joint (TMJ). Although there are several series reporting the use of postoperative radiotherapy (PORT) for extremity PVNS, there is scant literature on the use of PORT for PVNS of the TMJ. METHODS: We conducted a literature review for case reports related to PVNS of the TMJ and discuss two additional cases treated with surgery and PORT. RESULTS: 71 cases were found in the literature. 89% were the diffuse subtype. 92% had primary surgery and 7% had PORT. 68% were locally controlled. Both patients treated at our institution are locally controlled. CONCLUSIONS: PVNS of the TMJ is a rare entity. Surgery is the mainstay of treatment but PORT may be useful for local control of extensive tumors or positive margins.

[Effectiveness of arthroscopic synovectomy in treatment of pigmented villonodular synovitis of knee].

OBJECTIVE: To explore the effectivness of arthroscopic synovectomy in the treatment of pigmented villonodular synovitis (PVNS) of the knee. METHODS: A retrospective analysis was conducted on 13 patients with PVNS of the knee treated with arthroscopic synovectomy between June 2008 and December 2011, including 8 left knees and 5 right knees. There were 9 males and 4 females, aged 25-45 years (mean, 33 years). Of 13 patients, 5 had a history of trauma, and 8 had no history of trauma. The disease duration ranged from 4 months to 80 months (mean, 44 months). The preoperative Lysholm score was 45.3 +/- 4.2, and International Knee Documentation Committee (IKDC) 2000 score was 46.8 +/- 4.9. All patients underwent arthroscopic synovectomy and postoperative radiotherapy. RESULTS: The pathological examination proved PVNS in all cases. All incisions obtained healing by first intention after operation. There was no neurovascular injury or knee infection. The average follow-up period was 21.8 months (range, 12-30 months). The Lysholm score was 90.2 +/- 7.4, and IKDC2000 score was 87.8 +/- 3.8 at last follow-up, showing significant differences when compared with preoperative scores (t = 22.64, P = 0.00; t = 24.32, P = 0.00). No recurrence was observed during follow-up. CONCLUSION: Arthroscopic synovectomy can be effective in the treatment of PVNS of the knee, and it has the merits of minimal invasion, rapid function recovery of the knee joint, and satisfactory results. So it is a safe, promising, and minimal invasive procedure in treatment of PVNS.

[Effectiveness of arthroscopy and/or arthrotomy therapy for diffuse pigmented villonodular synovitis of the knee].

OBJECTIVE: To investigate the method and the effectiveness of arthroscopy and/or arthrotomy combined with postoperative radiotherapy for diffuse pigmented villonodular synovitis (PVNS) of the knee. METHODS: Between September 2000 and August 2010, 97 patients with diffuse PVNS of the knee were treated. There were 38 males and 59 females with a median age of 33 years (range, 8-75 years). The disease duration ranged from 1 week to 30 years, including 52 left knees and 45 right knees. There were 10 recurrent cases. The extention and flexion of the knee joint were (1.9 +/- 2.3) degrees and (122.9 +/- 5.6) degrees, respectively; the Lysholm score was 43.2 +/- 6.7; and the International Knee Documentation Committee (IKDC) score was 53.2 +/- 5.7, preoperatively. According to the scope and degree of the knee joint lesions, simultaneous anterior and posterior synovectomy was performed under arthroscopy in 82 cases, synovectomy under arthroscopy and removal of posterior extraarticular lesion by arthrotomy in 3 cases, synovectomy and the soft tissue lesions resection under arthroscopy in 9 cases, and staging resection and bone graft in 3 cases. After operation, 76 patients received postoperative radiotherapy. RESULTS: Popliteal artery was injuryed in 1 case and the branch of popliteal veins were injuryed in 3 cases during operation. Intra-articular hemorrhage occurred in 1 case at 3 days after operation. The other patients achieved healing of incision by first intention without nerve damage and other complications. All patients were followed up 1 year and 3 months to 11 years and 2 months (median, 61 months) postoperatively. During follow-up, 89 cases had no relapse. At 15 months after operation, the extention and flexion of the knee joint were (0.2 +/- 1.3) degrees and (135.9 +/- 6.6) degrees, respectively; the Lysholm score was 89.8 +/- 5.8; and the IKDC score was 87.8 +/- 5.8. All indexes were significantly improved when compared with the preoperative ones (P < 0.05). At 6 months to 8 years postoperatively, 8 cases had occurrence, and they had slight limitation of the range of motion but had no pain and swelling of the knees after reoperation. CONCLUSION: According to the scope and degree of the knee joint lesions, arthroscopy and/or arthrotomy combined with postoperative radiotherapy should be chosen for diffuse PVNS of the knee so as to obtain good effectiveness. Radiotherapy and enough total radiation dose are important factors to insure no recurrence.

Long-term success in the treatment of diffuse pigmented villonodular synovitis of the knee with subtotal synovectomy and radiotherapy.

PURPOSE: The objective of this study was to evaluate the effectiveness and long-term outcome of the treatment of patients with diffuse pigmented villonodular synovitis (PVNS) of the knee with subtotal arthroscopic and open synovectomy and subsequent external-beam radiotherapy. METHODS: Eight patients diagnosed with diffuse PVNS by clinical and magnetic resonance imaging were treated surgically with subtotal arthroscopic synovectomy and an additional posterior incision for extra-articular lesions, followed by local adjuvant radiotherapy. These patients were followed up for a mean of 8.6 years to monitor remaining lesions and to detect new occurrences of the condition. RESULTS: None of the patients presented with major postoperative complications or have had radiotherapeutic late effects. In no case was radiographic arthritis progression detected. Three patients exhibited late minor complications (peripatellar pain, articular effusion, and persistent quadricipital muscle atrophy). Only 1 patient (12.5%) presented with recurrence of the disease during the follow-up period. CONCLUSIONS: On the basis of our limited study, subtotal arthroscopic and open synovectomy with subsequent local external-beam radiotherapy had a recurrence rate of 12.5% at 8.6 years of follow-up for the treatment of diffuse PVNS of the knee joint. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Low-dose external beam radiotherapy as a postoperative treatment for patients with diffuse pigmented villonodular synovitis of the knee: 4 recurrences in 23 patients followed for mean 9 years.

BACKGROUND AND PURPOSE: Pigmented villonodular synovitis (PVNS) is a rare proliferative disorder involving synovial membranes, and patients with PVNS have a variable prognosis. We retrospectively analyzed clinical outcomes after synovectomy plus low-dose external beam radiotherapy for diffuse PVNS of the knee. METHODS: We reviewed the medical records of 23 patients who underwent postoperative radiotherapy between 1998 and 2007. 19 patients had primary disease and 4 had recurrent disease with an average of 2.5 prior surgeries. After synovectomy (17 arthroscopic surgeries; 6 open), all 23 patients received 4-MV or 6-MV external beam radiotherapy with a median dose of 20 (12-34) Gy in 10 fractions. RESULTS: At a median follow-up of 9 (0.8-12) years, 4 patients had recurrent disease, with a median disease-free interval of 5 years. Of these 4 patients, 3 received salvage synovectomy and regained local control. Univariate analysis showed that age, sex, history of trauma, and total dose of radiation were not predictive of local control. 22 patients reported excellent or good joint function, and 1 who refused salvage synovectomy had poor joint function. None of the patients experienced grade 3 or higher radiation-related toxicity or radiation-induced secondary malignancies. INTERPRETATION: Postoperative external beam radiotherapy is an effective and acceptable modality to prevent local recurrence and preserve joint function in patients with diffuse PVNS of the knee. Low-dose (20 Gy) radiotherapy appears to be as effective as moderate-dose treatment (around 35 Gy).

Long-term outcome of the treatment of high-risk tenosynovial giant cell tumor/pigmented villonodular synovitis with radiotherapy and surgery.

BACKGROUND: The treatment of diffuse tenosynovial giant cell tumor (TGCT) requires extensive surgical resection of the hypertrophic synovium and multiple soft tissue masses yet still may result in high rates of local failure. The authors of this report examined their experience in treating patients with advanced/multiply recurrent TGCT with a combination of surgery and external-beam radiotherapy. METHODS: Fifty patients who were treated for TGCT with radiotherapy and surgery from 1972 to 2006 were identified. Patient demographics, radiotherapy treatment parameters, surgical treatment, and oncologic and functional outcomes were evaluated. All patients had pathologic review at presentation and required at least 1 year follow-up. RESULTS: Forty-nine patients had diffuse TGCT with both intra-articular and extra-articular disease (1 had malignant TGCT). Twenty-eight patients (56%) were referred after at least 1 local recurrence. Thirty patients (60%) underwent at least 2 operations before radiotherapy. The mean dose of radiation delivered was 39.8 gray. At a mean follow-up of 94 months (range, 19-330 months), 47 patients (94%) had not developed a recurrence or had stable disease/signal characteristics on serial cross-sectional imaging (for those patients who had gross residual disease at the time of radiotherapy). Two patients required subsequent total hip arthroplasty because of progressive osteoarthritis, and there were 4 cases of avascular necrosis (only 1 post-treatment). Forty-one patients had good/excellent function. CONCLUSIONS: For patients with extensive or multiple local relapses or when surgery alone would result in a large burden of residual disease or major functional loss, the addition of moderate-dose adjuvant radiotherapy provided excellent local control while maintaining good function with low treatment-related morbidity.

Pigmented villonodular synovitis of the ankle-radiation therapy as a primary treatment to reduce recurrence: a case report with 8-year follow-up.

Pigmented villonodular synovitis (PVNS) is a rare, benign, idiopathic proliferative disorder of the synovium that results in villous and or nodular formations that have been reported to manifest within joints, tendon sheaths, and bursae. The overall incidence includes 2% to 10% that occur within the foot and ankle joints. PVNS has a high rate of recurrence and up to a 45% recurrence rate has been reported despite surgical intervention. Although traditional treatment for PVNS includes synovectomy with arthroplasty of the affected joint, radiation therapy is now suggested as an adjunctive therapy that is believed to reduce recurrence of the disease. We present a case of PVNS where the patient was treated in 2 stages: surgical resection of the tumor with arthroplasty of the ankle joint followed by radiation therapy. A retrospective review of the chart, radiographs, and MRIs was conducted for a 36-year-old, African American female who had been treated and followed for 8 years. Pathologic examination of the tumor confirmed the diagnosis of PVNS. No evidence of recurrent PVNS was identified in the long-term postoperative MRI examination. The fact that ancillary imaging examinations failed to reveal evidence of recurrence and that the patient expresses a very high patient satisfaction supports the potential benefit of adjunctive radiation therapy for this condition.

Radiation therapy for treatment of pigmented villonodular synovitis: results of a national patterns of care study.

PURPOSE: The German Cooperative Group on Radiotherapy in Benign Diseases (GCG-BD) conducted a pattern-of-care study (PCS) to analyze the radiation therapy (RT) practice for pigmented villonodular synovitis (PVNS). METHODS AND MATERIALS: In 2007, a structured questionnaire to assess the number of patients, the pretreatments, the RT indication, technique, target volume concepts, outcome data, and possible early or late toxicity was circulated to 227 institutions. RESULTS: Until August 2008, a response was available from 189 institutions (83.2 %), of whom 19 (10.0 %) experienced RT for PVNS. Complete clinical information was available for 41 patients from 14 RT departments. Thirty patients (73.2 %) received postsurgical RT because of primary incomplete resection, 11 patients (26.8 %) as an adjunct after complete resections of recurrences or unclear resection status. The total doses ranged from 30 to 50 Gy (median, 36 Gy), the median single dose was 2.0 Gy. Local control was achieved 95.1%, and 82.9% had no or only slight functional impairment. The early and late toxicity was mild (

External beam radiation therapy enhances local control in pigmented villonodular synovitis.

PURPOSE: Pigmented villonodular synovitis (PVNS) is a rare proliferative disorder of the synovium with locally aggressive behavior. We reviewed our experience using radiation therapy in the treatment of PVNS. MATERIALS AND METHODS: Seventeen patients with 18 sites of PVNS were treated with radiation between 1993 and 2007. Cases were retrospectively reviewed for patient information, treatment parameters, complications, and outcome. Seven sites were primary presentations and 11 were recurrent with an average of 2.5 prior surgical interventions. The most common location was the knee joint (67%). Cytoreductive surgery was performed before radiation therapy in 16/18 sites with all having proven or suspected residual disease. Radiation was delivered using 4-15 MV photons with an average total dose 34 Gy (range, 20-36 Gy). Seventeen of 18 sites (94%) had postradiotherapy imaging. RESULTS: With average follow-up of 46 months (range, 8-181 months), initial local control was achieved in 75% (12/16) of the sites with prior cytoreductive surgery (mean time to recurrence, 38 months). Ultimate local control was 100% after repeat resection (mean follow-up, 61 months). Two additional sites without prior cytoreductive surgery showed growth after radiotherapy (mean time to documented growth, 10.5 months). Seventeen of the 18 involved joints (94%) were scored as excellent or good PVNS-related function, one site (5%) as fair function, and no site with poor function. No patient required amputation; and there were no Grade 3/4 treatment-related complications. CONCLUSION: Postoperative external beam radiation is effective in preventing disease recurrence and should be offered following maximal cytoreduction to enhance local control in PVNS.