Pigmented villonodular synovitis of the knee: A retrospective analysis of 214 cases at a UK tertiary referral centre

AIMS

Pigmented villonodular synovitis (PVNS) is a rare, locally aggressive and potentially recurrent synovial disease. We present the largest single-centre experience of knee PVNS. Our aim was to evaluate our tertiary hospital's experience in the management of knee PVNS.

PATIENTS AND METHODS

Retrospective data collection of consecutive cases of knee PVNS from 2002 to 2015.

RESULTS

In total, 214 cases of knee PVNS were identified which represented 53.4% of all PVNS (12.1% were recurrent at presentation). 100 were localised PVNS (LPVNS), 114 diffuse PVNS (DPVNS) and two malignant PVNS. Knee PVNS was more likely to occur in females with a mean age of 39. Following surgery, 47.6% had recurrence with DPVNS as opposed to 8.6% with LPVNS. In LPVNS, there was no significant difference in recurrence between open and arthroscopic synovectomy (8.7% vs 9.1%, P>0.05). However, in DPVNS, there was a significantly higher risk of recurrence with arthroscopic compared to open synovectomy (83.3% vs 44.8%, RR=1.86 95% CI 1.32-2.62, P=0.0004).

CONCLUSION

PVNS can be difficult to treat. We found no difference in local recurrence rates between open and arthroscopic treatment of LPVNS but significantly increased rates of recurrence for DPVNS following arthroscopic treatment. We would therefore recommend open synovectomy for DPVNS.

How safe is curettage of low-grade cartilaginous neoplasms diagnosed by imaging with or without pre-operative needle biopsy?

The pre-operative differentiation between enchondroma, low-grade chondrosarcoma and high-grade chondrosarcoma remains a diagnostic challenge. We reviewed the accuracy and safety of the radiological grading of cartilaginous tumours through the assessment of, first, pre-operative radiological and post-operative histological agreement, and second the rate of recurrence in lesions confirmed as high-grade on histology. We performed a retrospective review of major long bone cartilaginous tumours managed by curettage as low grade between 2001 and 2012. A total of 53 patients with a mean age of 47.6 years (8 to 71) were included. There were 23 men and 30 women. The tumours involved the femur (n = 20), humerus (n = 18), tibia (n = 9), fibula (n = 3), radius (n = 2) and ulna (n = 1). Pre-operative diagnoses resulted from multidisciplinary consensus following radiological review alone for 35 tumours, or with the addition of pre-operative image guided needle biopsy for 18. The histologically confirmed diagnosis was enchondroma for two (3.7%), low-grade chondrosarcoma for 49 (92.6%) and high-grade chondrosarcoma for two (3.7%). Three patients with a low-grade tumour developed a local recurrence at a mean of 15 months (12 to 17) post-operatively. A single high-grade recurrence (grade II) was treated with tibial diaphyseal replacement. The overall recurrence rate was 7.5% at a mean follow-up of 4.7 years (1.2 to 12.3). Cartilaginous tumours identified as low-grade on pre-operative imaging with or without additional image-guided needle biopsy can safely be managed as low-grade without pre-operative histological diagnosis. A few tumours may demonstrate high-grade features histologically, but the rates of recurrence are not affected.

The present state of treatments for articular cartilage defects in the knee

INTRODUCTION

Chondral and osteochondral lesions of the knee are notoriously difficult to treat due to the poor healing capacity of articular cartilage and the hostile environment of moving joints, ultimately causing disabling pain and early osteoarthritis. There are many different reconstructive techniques used currently but few are proven to be of value. However, some have been shown to produce a better repair with hyaline-like cartilage rather than fibrocartilage.

METHODS

A systematic search of all available online databases including PubMed, MEDLINE(®) and Embase™ was undertaken using several keywords. All the multiple treatment options and methods available were considered. These were summarised, and the evidence for and against them was scrutinised.

RESULTS

A total of 460 articles were identified after cross-referencing the database searches using the keywords. These revealed that autologous and matrix assisted chondrocyte implantation demonstrated both 'good to excellent' histological results and significant improvement in clinical outcomes.

CONCLUSIONS

Autologous and matrix assisted chondrocyte implantation have been shown to treat symptomatic lesions successfully with significant histological and clinical improvement. There is, however, still a need for further randomised clinical trials, perfecting the type of scaffold and the use of adjuncts such as growth factors. A list of recommendations for treatment and the potential future trends of managing these lesions are given.

Proximal humeral replacement using a fixed-fulcrum endoprosthesis

Between 1997 and 2007, 68 consecutive patients underwent replacement of the proximal humerus for tumour using a fixed-fulcrum massive endoprosthesis. Their mean age was 46 years (7 to 87). Ten patients were lost to follow-up and 16 patients died. The 42 surviving patients were assessed using the Musculoskeletal Tumor Society (MSTS) Score and the Toronto Extremity Salvage Score (TESS) at a mean follow-up of five years and 11 months (one year to ten years and nine months). The mean MSTS score was 72.3% (53.3% to 100%) and the mean TESS was 77.2% (58.6% to 100%). Four of 42 patients received a new constrained humeral liner to reduce the risk of dislocation. This subgroup had a mean MSTS score of 77.7% and a mean TESS of 80.0%. The dislocation rate for the original prosthesis was 25.9; none of the patients with the new liner had a dislocation at a mean of 14.5 months (12 to 18). Endoprosthetic replacement for tumours of the proximal humerus using this prosthesis is a reliable operation yielding good results without the documented problems of unconstrained prostheses. The performance of this prosthesis is expected to improve further with a new constrained humeral liner, which reduces the risk of dislocation.

Current strategies for knee cartilage repair

Defects in knee articular cartilage (AC) can cause pain and disability and present the clinician with an extremely challenging clinical situation. This article describes the most up-to-date surgical techniques that aim to repair and/or regenerate symptomatic focal defects in AC, which include arthroscopic debridement, microfracture bone marrow stimulation and autologous osteochondral allografting, with an emphasis on autologous chondrocyte implantation. In the future, refinement of tissue-engineering approaches promises to further improve outcome for these patients.

Custom-made endoprostheses for the femoral amputation stump: an alternative to hip disarticulation in tumour surgery

Disarticulation of the hip in patients with high-grade tumours in the upper thigh results in significant morbidity. In patients with no disease of the proximal soft tissue a femoral stump may be preserved, leaving a fulcrum for movement and weight-bearing. We reviewed nine patients in whom the oncological decision would normally be to disarticulate, but who were treated by implantation of an endoprosthesis in order to create a functioning femoral stump. The surgery was undertaken for chondrosarcoma in four patients, pleomorphic sarcoma in three, osteosarcoma in one and fibrous dysplasia in one. At follow-up at a mean of 80 months (34 to 132), seven patients were alive and free from disease, one had died from lung metastases and another from a myocardial infarction. The mean functional outcome assessment was 50 (musculoskeletal tumor society), 50 and 60 (physical and mental Short-form 36 scores). Implantation of an endoprosthesis into the stump in carefully selected patients allows fitting of an above-knee prosthesis and improves wellbeing and the functional outcome.

A correlation between the timing of biopsy after autologous chondrocyte implantation and the histological appearance

Autologous chondrocyte implantation is an option in the treatment of full-thickness chondral or osteochondral injuries which are symptomatic. The goal of surgery and rehabilitation is the replacement of damaged cartilage with hyaline or hyaline-like cartilage, producing improved levels of function and preventing early osteoarthritis. The intermediate results have been promising in terms of functional and clinical improvement.

Our aim was to explore the hypothesis that the histological quality of the repair tissue formed after autologous chondrocyte implantation improved with increasing time after implantation.

In all, 248 patients who had undergone autologous chondrocyte implantation had biopsies taken of the repair tissue which then underwent histological grading. Statistical analysis suggested that with doubling of the time after implantation the likelihood of a favourable histological outcome was increased by more than fourfold (p < 0.001).

Local recurrence of osteosarcoma after 17 years

The recurrence of osteosarcoma is rare. Local recurrence occurs in 4-10% of patients following effective treatment. So far, recurrences as late as 15 years have been reported in the literature. We report a unique case of local recurrence of intramedullary osteosarcoma 17 years from initial diagnosis and treatment. Regular long-term follow-up of patients with this diagnosis is crucial to ensure early detection and treatment of potential recurrences.

An overview of autologous chondrocyte implantation

Chondral damage to the knee is common and, if left untreated, can proceed to degenerative osteoarthritis. In symptomatic patients established methods of management rely on the formation of fibrocartilage which has poor resistance to shear forces. The formation of hyaline or hyaline-like cartilage may be induced by implanting autologous, cultured chondrocytes into the chondral or osteochondral defect.

Autologous chondrocyte implantation may be used for full-thickness chondral or osteochondral injuries which are painful and debilitating with the aim of replacing damaged cartilage with hyaline or hyaline-like cartilage, leading to improved function. The intermediate and long-term functional and clinical results are promising.

We provide a review of autologous chondrocyte implantation and describe our experience with the technique at our institution with a mean follow-up of 32 months (1 to 9 years).

The procedure is shown to offer statistically significant improvement with advantages over other methods of management of chondral defects.

Clinical outcomes of extra-thoracic solitary fibrous tumours

BACKGROUND

Extra-thoracic solitary fibrous tumours (ESFTs) have traditionally been regarded as indolent neoplasms similar to their intra-thoracic counterparts. However there has been some evidence that a subset of more aggressively malignant tumours exist. We examined our experience with these rare tumours in an effort to clarify their clinico-pathological behaviour and relate this to their histopathological findings.

PATIENTS/METHODS

All patients with a histopathological diagnosis of solitary fibrous tumour (SFT) who presented to the Royal Marsden Hospital between 1998 and 2006 were reviewed. Clinico-pathological data were recorded for all cases and subset analysis performed to compare rates of locoregional recurrence, distant metastases and death.

RESULTS

There were 33 cases included in the study. 18 cases had malignant features on histological examination. Locoregional recurrent disease was more common in those with malignant histopathological findings compared to those with benign histopathology (6/18 vs 0/15 p 0.021). Distant metastatic disease was more common in those with malignant histopathological findings (7/18 vs 1/15 p 0.046) and these patients were at increased risk of death (10/18 vs 0/15 p<0.01). The presence of malignant histopathology was the only factor to affect survival with no benign cases dying of disease and malignant cases having a median survival of 59 months (p 0.003).

CONCLUSION

In our experience ESFTs have a higher rate of malignant behaviour than that classically described. Those tumours with atypical or malignant features on histological examination have poor prognosis and should be managed and followed up in the same manner as other high-grade soft tissue tumours.

Very late local recurrence of Ewing's sarcoma--can you ever say 'cured'? A report of two cases and literature review

We report two rare cases of very late local recurrence of Ewing's sarcoma, occurring 16 years and 19 years after treatment of the primary tumour. In both cases, disease remission had been achieved. Both patients originally underwent non-surgical combined modality therapy following initial diagnosis and both were rendered disease-free. After a long latent phase, both started experiencing unexplained local symptoms. These were investigated at their local hospital but tumour recurrence was not initially considered as a cause of these symptoms. The two patients were eventually referred back to our institution after the diagnosis of recurrent Ewing's sarcoma was established. Both have successfully undergone complete excision of the recurrences and are receiving postoperative adjuvant therapy. These cases highlight the need to remain vigilant for local recurrence, however long after the initial diagnosis.

Autologous chondrocyte implantation: where do we stand now?

Chondral damage to the young knee is common. In symptomatic patients current surgical treatment has focused on filling the defect with fibrocartilage; however, this tissue has poor resistance to shear forces, leading to failure and the onset of degenerative osteoarthritis.

Bicondylar osteochondritis dissecans in the knee

We describe two cases of osteochondritis dissecans (OCD) affecting both femoral condyles in the same knee. The patients presented with recurrent episodes of pain and swelling, but these were initially thought to be ‘growing pains’. Eventually, a delayed diagnosis of bicondylar OCD was established and both patients were referred for further management. After assessing the extent of the disease on MRI, matrix-induced autologous chondrocyte implantation was performed to treat the defects of the lateral condyle in each case, with a plan to address the medial defects at a later stage. Proposed theories on the aetiology of the condition and available methods of treatment are discussed. A diagnosis of OCD should be considered in young patients with persistent knee pain and effusions, and MRI is the investigation of choice for early detection.

Endoprosthetic replacement of the distal humerus following resection of bone tumours

Between 1988 and 2006, 18 patients had a custom-made endoprosthetic replacement of the distal humerus for bone tumours at our institution. There were 11 primary malignant neoplasms, six secondary deposits, and one benign aggressive tumour. The mean follow-up was for 4.4 years (1 to 18.2). Complications occurred in nine patients and included aseptic loosening in three (16.6%), local recurrence in two (11%), infection in two (11%), neuropraxia of the radial nerve in one (5.5%) and a peri-prosthetic fracture in one (5.5%). Excision was inadequate in four patients (22%), all of which developed local recurrence and/or metastases. There were seven deaths from the primary disease after a mean of 2.3 years (1 to 5), one of whom had an above-elbow amputation for local recurrence seven months before death. The remaining six had satisfactory elbow function at their last follow-up. The 11 living patients were evaluated using the Musculoskeletal Tumour Society and Toronto Extremity Salvage scoring systems. The mean scores achieved were 76% (67% to 87%) and 73% (59% to 79%), respectively. Overall, 17 of 18 patients had significant improvement in the degree of their pain following operation.

Custom-made endoprosthetic reconstruction of the elbow for bone tumours is a viable treatment in carefully selected patients. It maintains satisfactory function and provides good pain relief.

Phytoestrogens and the risk of breast cancer: a review of the literature

BACKGROUND

Over the last decade, interest in the physiological role of bioactive compounds in plants has increased dramatically. Of particular interest in relation to human health are the class of compounds known as the phytoestrogens, which embody several groups of nonsteroidal estrogens that are widely distributed within the plant kingdom, including isoflavones and lignans. Epidemiological studies suggest that diets rich in phytoestrogens, particularly soy and unrefined grain products, may be associated with low risk of breast cancer. This review presents the studies published so far exploring a link between dietary phytoestrogens and breast cancer risk.

METHODS

A Medline search was conducted using the key words below. Further articles were obtained by cross-matching references of relevant articles. Twenty-one case-control and 15 prospective studies were identified since 1978. One meta-analysis and several review articles also were noted.

RESULTS

Results from previous studies were analyzed and comparisons were made between each type of study. Controversy exists regarding this subject, and we found conflicting evidence in recent literature regarding this hypothesis.

CONCLUSION

There is no clear evidence that phytoestrogen intake influences the risk of developing breast cancer.