Diffuse pigmented villonodular synovitis of the foot and ankle treated with surgery and radiotherapy

Pigmented Villonodular Synovitis of Ankle Joint - A Case Report

Introduction

Pigmented villonodular synovitis (PVNS)is a very uncommon lesion that involves the synovium of joints, tendon sheaths, or bursae. Approximately 2.5% of cases occur around the ankle. PVNS was earlier considered to be a synovial malignancy. Complete surgical excision is curative if bony destruction is not there. Radiotherapy is rarely helpful for residual lesions.

Case Report

We share a case report on PVNS of ankle in a 22-years old male patient. Clinical diagnosis was confirmed with the help of magnetic resonance imaging and histopathology. A surgical excision with synovectomy was carried out. There were no signs of recurrence in 1.5 years follow-up.

Conclusion

Complete surgical excision with radical synovectomy is crucial for the treatment of PVNS in rare locations like the ankle joint.

Outcomes of Tenosynovial Giant Cell Tumor of the Foot and Ankle

BACKGROUND

Tenosynovial giant cell tumor (TGCT) is a benign proliferative disease affecting synovial membranes. There are 2 forms, localized (L-TGCT) and diffuse (D-TGCT), which although histologically similar behave differently. It is locally invasive and is treated in most cases by operative excision. The aim of this study was to assess current practice, how the patients' presentation affected their outcome, as well as review the recurrence rates and complications.

METHODS

A retrospective analysis of 123 cases was performed in patients treated between 2003 and 2019 with TGCT of the foot and/or ankle. Data were collected on age at presentation, radiologic pattern of disease, location of disease, treatment provided, and recurrence rates. The minimum follow-up was 2 years with a mean of 7.7 years.

RESULTS

There were 61.7% female patients with a mean age of 39 (range, 11-76) years. L-TGCT accounted for 85 (69.1%) cases and D-TGCT for 38 (30.9%). The most prevalent preoperative symptoms were a palpable mass (78/123) and pain (65/123). Radiologically confirmed recurrence in the operative group was noted in 14.5% (16/110) cases. This comprised 4% (3/75) of operatively treated L-TGCT and 37% (13/35) of operatively treated D-TGCT. Patients with pain on presentation and those with erosive changes on presenting magnetic resonance imaging (MRI) were more likely to have persistent postoperative pain (P < .001 for both). Where patients had both preoperative pain and erosive changes, 57.1% had postoperative pain. Thirteen cases were managed nonoperatively where symptoms were minimal, with 1 case requiring surgery at a later date.

CONCLUSION

Outcomes of TGCT management are dependent on the disease type, extent of preoperative erosive changes, and presence of preoperative pain. These data are useful for counseling patients regarding the outcomes of surgical intervention and help guide the timing of intervention.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Diffuse Tenosynovial Giant Cell Tumor Encircling the First Metatarsal Bone Remodeling after Resection. A Case Report

Introduction

The term tenosynovial giant cell tumor encompasses a group of rare soft-tissue tumors. A new classification divides the group in localized and diffuse type, depending on the involvement of the surrounding tissues. Due to the unclear origin and heterogeneity in extend of the diffuse-type giant cell tumors, there is only limited evidence on the tumor-specific treatment. Thus, every case report has an added value toward setting disease-specific guidelines.

Case Report

Presentation of a diffuse type tenosynovial giant cell tumor encircling the first metatarsal. The tumor had mechanically eroded the plantar aspect of the distal metaphysis, with no signs of tumor spread. After an open biopsy, resection of the mass was performed without debriding or resecting the first metatarsal. Repeat imaging postoperatively showed no recurrence at 4-year follow-up and a bony remodeling of the lesion.

Conclusion

Bone remodeling is possible after complete resection of diffuse tenosynovial giant cell tumor when the erosion is caused by mechanical pressure and no intraosseous expansion of the tumor is present.

Pigmented Villonodular Synovitis of Flexor Hallusis Longus, Flexor Digitorum Longus, Tibialis Posterior: A Rare Case Report

Pigmented villonodular synovitis (PVNS) is a locally aggressive benign tumour of the synovial membrane and tendon sheath. The unique presentation of this tumour is hemosiderin deposition with synovial proliferation. Depending on the situation, surgical excision is always the first line of treatment with adjuvant radiotherapy. Arthroscopic excision is preferred in some intraarticular nodular PVNS cases. This is a rare pigmented villonodular synovitis involving flexor hallusis longus, flexor digitorum longus, and tibialis posterior (TP). The tumour was entirely extra-articular without any joint involvement. The tumour was the diffuse type of PVNS and was treated by excision followed by radiotherapy. There is no recurrence till nine months of follow-up.

Anterior Capsule Reconstruction in the Setting of PVNS

BACKGROUND

Pigmented villonodular synovitis (PVNS) is a benign proliferative disease affecting tendon sheaths and synovial tissue. Pigmented villonodular synovitis in the foot and ankle has a high rate of recurrence, which can be destructive if incompletely removed. This case series analyzes functional outcomes after PVNS operative resection with an anterior ankle capsular reconstruction, using a novel technique.

METHODS

Three patients with PVNS underwent surgery between 2010 and 2020. The operative technique involved a posterior, midline approach for PVNS resection of the affected ankle joint, followed by a standard anterior approach for capsular excision. Subsequent anterior capsular reconstruction was performed with a regenerative tissue matrix and a bioresorbable anchoring system. Preoperative and postoperative range of motion for the ankle and subtalar joints, visual analog scale (VAS) for pain, and return to daily activities was assessed along with appropriate radiographs and magnetic resonance imaging (MRI) imaging.

RESULTS

All 3 surgeries had a mean follow-up period of 52.3 (range, 4-123) months and resulted in successful recovery as assessed by the VAS and self-reported activity. Preoperative ankle dorsiflexion and plantarflexion along with subtalar inversion and eversion range of motion were all normal. Postoperative ankle motion and subtalar motion were not statistically different. No complications or recurrence of PVNS was observed.

CONCLUSION

Further investigation is warranted to better understand the clinical outcomes of this technique designed to successfully eliminate PVNS recurrence.

LEVEL OF EVIDENCE

IV- Retrospective case series.

Treatment, recurrence rates and follow-up of Tenosynovial Giant Cell Tumor (TGCT) of the foot and ankle-A systematic review and meta-analysis

Background

The tenosynovial giant cell tumor (TGCT) is a usually benign lesion which arises from the synovium. It affects joints, tendon sheaths and bursae. The clinical course is often unpredictable, and local recurrences frequently occur. The aim of this study was to describe different treatment options, surgical complications, and to develop a follow-up regime based on a systematic literature review and meta-analysis of foot and ankle lesions.

Methods and results

1284 studies published between 01/1966 and 06/2021 were identified. 25 met the inclusion criteria, with a total of 382 patients. Of these, 212 patients had a diffuse (dTGCT) and 170 a localized (lTGCT) TGCT. Patients with a dTGCT had a mean age of 36.6±8.2 years, and 55% were female. The overall complication rate was 24% in dTGCT, irrespective of the therapeutic procedure; the mean follow-up was 37.9±27.4 months with a recurrence rate of 21%, and recurrences occurred between 3 and 144 months, the vast majority (86%) within the first 5 years following intervention. Patients with a lTGCT had a mean age of 31.2±5.7 years, and 53% were female. Complications occurred in 12%. The mean follow-up was 51.1±24.6 months, the recurrence rate was 7%, and recurrence occurred between 1 and 244 months after intervention.

Conclusion

Diffuse TGCTs of the foot and ankle region have a remarkable recurrence rate irrespective of therapeutic procedures, and most lesions reoccurred within 5, with more than half of these in the first 2 years. The lTGCTs are well treatable lesions, with a low recurrence and a moderate complication rate. Based on these findings, we propose a follow-up regime for the dTGCT including a clinical survey and MR imaging 3 months after surgical intervention (baseline), followed by twice-yearly intervals for the first 2 years, yearly intervals up to the fifth year, and further individual follow-up due to the fact that recurrences can even occur for years later. For the lTGCT a clinical survey and MRT is proposed after 3–6 months after intervention (baseline), followed by annual clinical examination for 3 years, and in case of symptoms MR-imaging. Larger prospective multi-center studies are necessary to confirm these results and recommendations.

Radiosynoviorthesis after Surgery in the Treatment of Patients with Ankle Pigmented Villonodular Synovitis: A Case Series

Pigmented villonodular synovitis (PVNS) of the ankle is a very rare, locally aggressive, proliferative disorder. Although surgical excision represents the standard curative treatment, the PVNS relapse rate is high. We present our study of five young athletes (range 20–36 years) with a histopathological diagnosis of PVNS of the ankle, who were treated by surgery and adjuvant radiosynoviorthesis (RSO). The operation involved either arthroscopic (four patients) or open (one patient) debridement, followed by intraarticular RSO with the radiopharmaceutical erbium-169 (¹⁶⁹Er). They were evaluated with the Foot Function Index (FFI) and a visual analog scale (VAS) for pain. At a median follow up period of 47 months (range 36–54 months), all five patients reported marked pain relief with improvements in their daily activities. In particular, the median FFI decreased from 77% (range 71.0%–84.5%) pre-treatment, to 0.5% (range 0%–6%) after treatment. The median VAS score decreased from 4 (range 3–7) to 0 (range 0–1), respectively. Throughout the follow-up period, there were no major complications regarding either therapeutic intervention (arthroscopic or open debridement, RSO). Based on these results, it can be concluded that adjuvant RSO with ¹⁶⁹Er following surgical excision is effective and safe in the treatment of PVNS of the ankle.

Endoscopic Approach for the Excision of Giant Cell Tumor of Tendon Sheath Involving the Hindfoot: A Case Report

Giant cell tumor of tendon sheath (GCT-TS) is an often benign neoplasm that is relatively uncommon in the foot and ankle when compared to the upper extremities. Magnetic resonance imaging aids in characterizing the lesion, but diagnosis is confirmed with biopsy. Surgical excision is the preferred treatment. There is a lack of studies examining the long-term outcomes of endoscopic excision of GCT-TS, especially lesions found in the foot and ankle. The present study describes a case of a 42-year-old male with GCT-TS of the hindfoot treated with an endoscopic excision through a sinus tarsi approach. The patient was asymptomatic with no local signs of recurrence at the 67-month follow-up visit.

Diffuse Pigmented Villonodular Synovitis Around the Ankle

BACKGROUND

Pigmented villonodular synovitis (PVNS) is a rare disorder around the ankle joint. The optimal treatment for diffuse-type PVNS is still controversial because of the high incidence of recurrence. We present the clinical features of our patients and review the current diagnostic and treatment modalities.

METHODS

Five patients with PVNS located around the ankle were surgically treated. In three patients, diffuse PVNS arose from the ankle joint, and in the other two it arose from the calcaneocuboid and intercuneiform joints. The average follow-up time after surgery was 2.9 years (range, 2-4.6 years).

RESULTS

The average time between onset of pain and diagnosis of PVNS was 6.4 years (range, 4-10 years). Arthrotomic tumor resection was performed in all of the patients. In the three patients with ankle joint PVNS, both medial and lateral approaches were used. One patient experienced mild infection at the surgical site, but this healed conservatively. No tumor recurrences had occurred after minimum follow-up of 2 years, although mild pain persisted in the three patients with ankle PVNS.

CONCLUSIONS

Diagnosis of diffuse PVNS is frequently delayed due to vague symptoms and variable growth patterns. Orthopedic clinicians should be aware of the existence of this lesion, and it should be suspected in patients with persistent ankle swelling. To prevent tumor recurrence, accurate evaluation of tumor location and careful operative planning are mandatory. A combined surgical approach involving medial and lateral incision is necessary to expose the entire joint cavity.

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.

Surgical treatment for diffused-type giant cell tumor (pigmented villonodular synovitis) about the ankle joint

Background

Diffused-type giant cell tumor(Dt-GCT) is a rare, aggressive disorder of the joint synovium, bursa and tendon sheaths. Osseous erosions and subchondral cysts may develop as the result of synovium infiltration in Dt-GCT. We present a retrospective study of a series of patients who are diagnosed with Dt-GCT about the ankle joint, there clinical outcome is evaluated in this study.

Material and method

Fifteen patients with radiologically and histologically confirmed Dt-GCT about the ankle joint were identified in our foot and ankle department. Patients were managed with open synovectomy for the tumor tissue and bone grafting for bony erosions. X-rays and MRI scans were used for evaluation of the tumor and bony erosions pre- and post-operatively. Pre- and post-operative ankle function was assessed using the American Orthopedic Foot and Ankle Society –Ankle and Hindfoot (AOFAS-AH) score and the Muscularskeletal Tumor Society (MSTS) score.

Results

The mean follow-up duration was 37.4 months (range 25 to 50 months). There were 6 males and 9 females, with a mean age of 35 years old (range 18 to 65 years). All patients had talar erosion with the average size of 10.1*9.1*8.2 mm, distal tibia was affected in 5 patients with the average size of 6.2*5.6*5.8 mm. 7 patients had tendon involvement, 2 patients had recurrence and progression of ankle osteoarthritis. Both of them underwent ankle fusion. At the time of last follow-up, the mean AOFAS-AH score increased from 49 to 80 points (p < 0.05), the MSTS score increased from 12 to 22 points (p < 0.05).

Conclusion

For Dt-GCT with bony erosions, open synovectomy combined with bone grafting seems to be a safe and effective operation for the salvage of ankle joint. Fusion is recommended for failed and severe cartilage destruction of the ankle joint.

Villonodular synovitis of the ankle. Analysis of the risk of recurrence

INTRODUCTION

Villonodular synovitis (VNS) is a rare disease with an incidence of 1.8 per 1,000,000 inhabitants. VNS of the ankle has seldom been described and evaluated given its extreme rarity (2.5% of VNS cases). It presents an 11% recurrence rate. We report a continuous retrospective series with the main objective of clinically and radiologically evaluating these ankles searching for any risk factors of recurrence. At revision the study's main endpoint was the existence of local recurrence (radiological and clinical) and the secondary endpoint was the existence of tibiotalar osteoarthritis. The working hypothesis was that recurrence could be subclinical, warranting systematic imaging studies during follow-up.

MATERIAL AND METHODS

The study was retrospective, conducted on seven patients (six males) whose mean age was 42 years treated over a period of 9 years (two diffuse forms and five localized forms). The initial treatment consisted in synovectomy via the conventional approach. Four patients also received adjuvant isotopic synoviorthesis treatment. The revision was clinical (MMTS, AOFAS, and OMAS scores) and radiological (standard and MRI) to evaluate the joint after-effects and search for recurrence.

RESULTS

Six patients were seen at a mean 6.5 years of follow-up. One case of early recurrence (4 years) was noted, with a major clinical manifestation because it was associated with joint destruction requiring arthrodesis, and one case of late asymptomatic recurrence (9 years), diagnosed radiologically on the follow-up MRI. The functional results remained good at follow-up (MMTS 77%, AOFAS 71, OMAS 71). Five of the six patients returned to their daily activities. At revision, no sign of osteoarthritis was observed. No risk factor for recurrence was demonstrated.

DISCUSSION/CONCLUSION

The hypothesis was confirmed with the existence of asymptomatic recurrence at revision, underscoring the value of systematic MRI at follow-up. Other than major joint destruction, the prognosis remains good even in case of recurrence. The literature emphasizes the existence of an initial diffuse form and partial surgical resection as risk factors of recurrence. None of the reports in the literature has proven that adjuvant treatment, whose modalities do not meet with consensus, reduces this risk.

LEVEL OF EVIDENCE

Retrospective series, level IV.

Pigmented villonodular synovitis of the temporomandibular joint with intracranial extension

Pigmented villonodular synovitis is an uncommon benign tumor-like proliferative lesion with an undetermined origin. Involvement of the temporomandibular joint is uncommon. Although pigmented villonodular synovitis is a benign lesion, it can grow with an aggressive pattern, and it extends extra-articularly in most of the reported cases, about one-third of them exhibiting intracranial involvement. The authors reported an additional case of a 47-year-old woman with intracranial extension, who had a history of joint pain and trismus. The preoperative diagnosis was made with arthroscopy. The lesion was completely excised via preauricular approach and condylotomy. The bone defect was covered by the pedicled temporalis myofascial fat flap. The patient has been symptom-free for 40 months postoperatively.

Surgical outcomes after excision of pigmented villonodular synovitis localized to the ankle and hindfoot without adjuvant therapy

Although a benign disorder, pigmented villonodular synovitis (PVNS) has a high rate of recurrence. Because of the high incidence of recurrence and concern about destruction of the affected joint, several adjuvant therapies have been promoted without a clear standard treatment strategy. We reviewed cases of PVNS affecting the ankle and hindfoot joints (ankle and/or subtalar joints) treated with surgical resection without adjuvant therapy in an effort to identify the incidence of PVNS recurrence after excision without adjuvant therapy. Of the 10 cases with a mean follow-up duration of 33.2 ± 19.8 months, 4 (40%) developed a recurrence, with a mean interval of 6 (range 3 to 14) months. At the final follow-up visit, the mean American Orthopaedic Foot and Ankle Society ankle-hindfoot score was 86.6 ± 12. The clinical outcomes of PVNS affecting the ankle and hindfoot joints are associated with a relatively high incidence of recurrence, and additional clinical investigation comparing the incidence of recurrence in patients undergoing excision versus excision with adjuvant therapy is needed for us to better understand this condition and provide more informed recommendations to our patients.

Clinical and oncological outcomes after surgical excision of pigmented villonodular synovitis at the foot and ankle

BACKGROUND

Pigmented villonodular synovitis (PVNS) is a rare benign neoplastic disease of the synovium of joints and tendon sheaths, which may be locally aggressive. It can be broadly classified into localised disease or more diffuse forms, with the latter more prone to recurrence after surgical excision. We describe our experience in the management of foot and ankle PVNS, focusing on the diffuse type.

METHODS

Patients with PVNS were identified from a histology database from 2000 to 2010 at the University Hospitals of Leicester. The primary aim was to determine oncological outcomes and evaluate clinical outcomes with the Toronto Extremity Salvage Score (TESS) and the American Academy of Foot and Ankle Surgeons (AOFAS) scores.

RESULTS

30 patients, 16 males and 14 females with a mean age of 37±15 years, who underwent surgery, were identified. There were 22 nodular PVNS and 8 diffuse PVNS. The diffuse PVNS was more likely to be in the hindfoot (75%, 6/8), of which 50% (3/6) had osteoarthritis at presentation. The localised PVNS was mostly located in the forefoot (91%, 20/22). None of the localised PVNS had a recurrence. The surgical recurrence rate in this series was similar to the pooled recurrence rate from the literature [12.5% (1/8) compared to 12.2% (6/49)]. The mean TESS and AOFAS scores were 86 and 78, respectively.

CONCLUSIONS

Diffuse PVNS is more likely to occur in the hindfoot and nodular PVNS is more common in the forefoot. Aggressive synovectomy alone is an effective treatment for diffuse PVNS, with good oncological and clinical outcomes.

Pigmented villonodular synovitis great toe

A young boy of 14 years. presented with swelling over dorsal aspect of right great toe, which was slightly tender, non fluctuant. It was excised under subarachnoid block. The mass was golden brown in colour encircling the extensor tendon (Extensor Hallucis Longus Tendon). Histopathology reported to be Pigmented Villonodular Synovitis.

Diffuse pigmented villonodular synovitis (diffuse-type giant cell tumour) of the foot and ankle

Pigmented villonodular synovitis (PVNS) is a rare benign disease of the synovium of joints and tendon sheaths, which may be locally aggressive. We present 18 patients with diffuse-type PVNS of the foot and ankle followed for a mean of 5.1 years (2 to 11.8). There were seven men and 11 women, with a mean age of 42 years (18 to 73). A total of 13 patients underwent open or arthroscopic synovectomy, without post-operative radiotherapy. One had surgery at the referring unit before presentation with residual tibiotalar PVNS. The four patients who were managed non-operatively remain symptomatically controlled and under clinical and radiological surveillance. At final follow-up the mean Musculoskeletal Tumour Society score was 93.8% (95% confidence interval (CI) 85 to 100), the mean Toronto Extremity Salvage Score was 92 (95% CI 82 to 100) and the mean American Academy of Orthopaedic Surgeons foot and ankle score was 89 (95% CI 79 to 100). The lesion in the patient with residual PVNS resolved radiologically without further intervention six years after surgery. Targeted synovectomy without adjuvant radiotherapy can result in excellent outcomes, without recurrence. Asymptomatic patients can be successfully managed non-operatively. This is the first series to report clinical outcome scores for patients with diffuse-type PVNS of the foot and ankle.

Adult multifocal pigmented villonodular synovitis--clinical review

Pigmented villonodular synovitis (PVNS) is a rare, benign proliferative disease of the synovial tissue that affects a single joint or a tendon sheath. Data from the literature present only a few cases of multifocal PVNS. This paper presents multifocal PVNS in the adult. This disease can affect bilateral shoulders, hips and knees. The diagnosis may be delayed by the slow evolution of the disease (up to ten years); some patients may be seen with late-stage degenerative joints, serious complications, painful and functionally uncompensated, with significant locomotion deficit. PVNS requires a radical treatment with prosthetic arthroplasty associated with synovectomy. Complex imaging (X-Rays, magnetic resonance imaging (MRI), ultrasound) and macroscopic appearance of the lesions during surgery confirms the clinical diagnosis of multifocal PVNS with secondary bone lesions. Histology marks the final diagnosis of multifocal PVNS. The postoperative results are good, with recovery in functional parameters of the joints with endoprosthesis.

Dosimetry of small bone joint calculated by the analytical anisotropic algorithm: a Monte Carlo evaluation using the EGSnrc

This study compared a small bone joint dosimetry calculated by the anisotropic analytical algorithm (AAA) and Monte Carlo simulation using megavoltage (MV) photon beams. The performance of the AAA in the joint dose calculation was evaluated using Monte Carlo simulation, and dependences of joint dose on its width and beam angle were investigated. Small bone joint phantoms containing a vertical water layer (0.5‐2 mm) sandwiched by two bones (2×2×2cm3) were irradiated by the 6 and 15 MV photon beams with field size equal to 4×4 cm2. Depth doses along the central beam axis in a joint (cartilage) were calculated with and without a bolus (thickness=1.5cm) added on top of the phantoms. Different beam angles (0°‐15°) were used with the isocenter set to the center of the bone joint for dose calculations using the AAA (Eclipse treatment planning system) and Monte Carlo simulation (the EGSnrc code). For dosimetry comparison and normalization, dose calculations were repeated in homogeneous water phantoms with the bone substituted by water. Comparing the calculated dosimetry between the AAA and Monte Carlo simulation, the AAA underestimated joint doses varying with its widths by about 6%‐12% for 6 MV and 12%‐23% for 15 MV without bolus, and by 7% for 6 MV and 13%‐17% for 15 MV with bolus. Moreover, joint doses calculated by the AAA did not vary with the joint width and beam angle. From Monte Carlo results, there was a decrease in the calculated joint dose as the joint width increased, and a slight decrease as the beam angle increased. When bolus was added to the phantom, it was found that variations of joint dose with its width and beam angle became less significant for the 6 MV photon beams. In conclusion, dosimetry deviation in small bone joint calculated by the AAA and Monte Carlo simulation was studied using the 6 and 15 MV photon beam. The AAA could not predict variations of joint dose with its width and beam angle, which were predicted by the Monte Carlo simulations.

PACS numbers: 87.55.K‐; 87.53.Bn; 87.53.‐j

A multidisciplinary approach to giant cell tumors of tendon sheath and synovium--a critical appraisal of literature and treatment proposal

Giant cell tumors deriving from synovium are classified into a localized (GCT of tendon sheath; GCT-TS) and diffuse form (diffuse-type GCT, Dt-GCT). We propose a multidisciplinary management based upon a systematic review and authors' opinion. Open excision for GCT-TS and open synovectomy (plus excision) for Dt-GCT is advised to reduce the relatively high recurrence risk. External beam radiotherapy should be considered in severe cases, as Dt-GCT commonly extends extra-articular.

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).

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.