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Franklin H Sim

Publications and source records attributed to Franklin H Sim.

At least 19 recordsLinked to original sources
PubMed2004

Absence of a correlation between the presence of a single nucleotide polymorphism in the matrix metalloproteinase 1 promoter and outcome in patients of chondrosarcoma.

PURPOSE: Increased levels of matrix metalloproteinase 1 (MMP-1) expression have been associated with poor outcome in chondrosarcoma. The existence of a single nucleotide polymorphism creating an Ets-binding site in the MMP-1 promoter may be one mechanism for elevated MMP-1 transcription. The aim of our study was to identify the prevalence of this single nucleotide polymorphism (SNP) in chondrosarcoma patients, to determine its correlation with disease outcome, and to discern whether it could serve as a prognostic marker in patients with chondrosarcoma. EXPERIMENTAL DESIGN: Sixty-seven chondrosarcoma specimens were selected sequentially from an established tumor bank with a median duration of 47 months follow-up (range, 24 to 179 months). DNA was extracted, amplified with PCR, and sequenced to determine presence (GG) or absence of the Ets-binding site created by the SNP. RESULTS: Eighteen (27%) samples were homozygous for the absence of the Ets site, 34 (51%) were heterozygous for the SNP, and 15 (22%) were homozygous for the SNP. The 5-year overall survival rate for patients was 78, 80, and 84%, respectively (P = 0.5527). The disease-free survival rate was 16, 63, and 76%, respectively (P = 0.0801). The 5-year disease-free survival rate for patients with the homozygous G/G genotype was 16%, compared with 71% for patients who were either homozygous or heterozygous for the GG allele (P = 0.0444). CONCLUSIONS: Despite a statistical correlation between MMP-1 gene expression and outcome in chondrosarcoma, this study demonstrates an absence of a correlation between the presence of the SNP and prognosis in patients with chondrosarcoma.

Adult↗
PubMed2004

Imaging features of low-grade central osteosarcoma of the long bones and pelvis.

PURPOSE: To determine the age and gender distribution and imaging features of low-grade central osteosarcoma (LGCOS) of the long bones and pelvis and to discuss our findings in the context of lesions for which LGCOS has been mistaken. MATERIALS AND METHODS: We reviewed 99 cases of LGCOS collected between 1919 and 2002 from our institution and pathology consultation files. Adequate imaging was available in 70 cases (36 radiographs only, 17 radiographs/CT, 12 radiographs/MRI, 2 radiographs/CT/MRI, 2 CT only, 1 MRI only, 5 bone scans). RESULTS: Patient average age was 30.1+/-14.2 years, with a slight female predominance. The femur and tibia were the most common long bones involved (29 and 20 each) with the majority of these tumors arising around the knee, followed by the fibula, radius, humerus and ulna (four, three, two and one case each). Flat bones were involved in six cases (three pelvis, one rib, two scapulae). Short tubular bones were involved in five cases (two metatarsal, two phalanges, one clavicle). The lesion extended to the end of the affected long bone in 22 of 59 cases. Lesions were large at presentation (mean 7.9+/-4.6 cm, range 2-24). Four radiographic patterns were identified: lytic with varying amounts of thick and coarse trabeculation ( n=22), predominantly lytic with few thin, incomplete trabecula ( n=21), densely sclerotic ( n=17) and mixed lytic and sclerotic ( n=10). Lesions were benign-appearing overall with focally aggressive features. CT or MRI demonstrated cortical breech or extension into the soft tissues in all cases. CONCLUSIONS: LGCOS has a variable appearance on radiographs. A frequent pattern is a slow-growing large intracompartmental fibro-osseous lesion with varying amounts of septal ossification associated with focal areas of aggression. A homogeneously sclerotic pattern was also noted. Imaging with CT or MRI was helpful in every instance in our series in identifying areas of soft tissue extension or cortical disruption suggestive of a low-grade malignancy.

Adult↗
PubMed2004

Proximal femoral replacements with megaprostheses.

The exact role of proximal femoral replacement (megaprosthesis) in revision hip surgery is unclear. During the past decade remarkable advances in the field of revision hip reconstruction have been made including the availability of allograft cancellous and cortical bone. With the increased use of cortical strut grafts to augment host bone, the indications for the use of megaprostheses have narrowed. Currently, we reserve the use of megaprostheses for elderly or sedentary patients with massive proximal femoral bone loss that cannot be reconstructed by other reconstructive procedures. This may include failed total hip arthroplasty (THA), nonunion of the proximal femur with multiple failed attempts at osteosynthesis, and hip salvage after a failed resection arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed2004

The modular segmental kinematic rotating hinge for nonneoplastic limb salvage.

From January 1980 to July 1998, 25 patients (26 knees) were treated with an arthroplasty using a Modular Segmental Kinematic Rotating Hinge total knee prosthesis for nonneoplastic limb salvage. The indications included: nonunion of a periprosthetic femur fracture (11 knees), severe bone loss and ligamentous instability (eight knees), nonunion of a supracondylar femur fracture (four knees), acute periprosthetic fracture (one knee), fracture of a previous hinge (one knee), and prior resection arthroplasty (one knee). The average age of the patients was 72.3 years. Twenty-two arthroplasties were revisions. The average followup was 58.5 months. At the latest followup, knee extension averaged 2.4 degrees and flexion averaged 93.6 degrees. The Knee Society knee score improved from an average of 45.4 preoperatively to 75.5. Preoperatively, functional scores averaged 8.6 and improved to 25. Complications occurred in eight patients. The most common was deep infection (five patients). The use of the Modular Kinematic Rotating Hinge for nonneoplastic limb salvage represents a small proportion (0.14%) of all primary and revision knee arthroplasties done at our institution. The indications for the surgery are for a highly complex and small subset of patients. The patients in the current study gained significant improvement in overall range of motion, Knee Society knee scores, and functional scores when this prosthesis was used.

Aged↗
PubMed2004

Chondrosarcoma of the chest wall: a retrospective clinical analysis.

Primary chondrosarcoma of the chest wall is uncommon, and reports of treatment from one institution are limited. Treatment of this lesion is difficult because of the anatomic location, which is in close proximity to surrounding neurovascular and visceral structures. The purpose of this study was to review the outcome of surgical resection of chondrosarcoma of the chest wall, and to delineate the prognostic factors related to local recurrence and survival. Twenty-four patients with chondrosarcoma of the chest wall were treated at our institution between 1986 and 2000. There were 14 males and 10 females, with an average age of 54 years (range, 11-76 years). Patients were observed for a minimum of 3 years or until death. The median followup was 71 months. The anatomic locations of chondrosarcoma of the chest wall were the rib in 16 patients, the ribs and sternum in two patients, the ribs and spine in three patients, and the sternum only in three patients. Histologically, 17 patients had Grade 1 disease and seven patients had Grade 2 disease. At followup, 17 patients were alive without disease, two were alive with disease, two died without disease, and three died secondary to progressive disease. The overall survival estimate at 5 years was 92%. The recurrence rate for patients with adequate surgical margins was 10%, compared with 75% for patients with inadequate margins. The 5-year survival rate for patients with adequate surgical margins was 100%, compared with 50% in patients with inadequate surgical margins. An inadequate margin of resection was associated with a significantly worse overall survival and a higher chance of having local recurrence develop.

Adolescent↗
PubMed2004

Scapular chondrosarcomas have high rates of local recurrence and metastasis.

This is the first report of a large series of patients with scapular chondrosarcomas. The grade distributions, locations of the tumors in the scapula, surgical techniques, status of margins, chondrosarcoma subtypes, Enneking stages, adjuvant therapies, local recurrence rates, metastasis rates, and survival prognoses of patients with scapular chondrosarcoma were evaluated. Forty-seven patients treated between 1921 and 1999 were analyzed retrospectively. Grade 3 disease was significantly associated with a poorer survival prognosis when compared with Grades 1 or 2 disease. Patients with tumors smaller than 5 cm were treated mainly with partial scapulectomy, and patients with tumors larger than 5 cm often were treated with total scapulectomy. The survival prognoses of patients with intralesional resections at initial surgery showed a tendency toward poorer survival when compared with patients with wide resections at initial surgery. Metastasis and local recurrence (21.3% and 40.4%) were higher in scapular chondrosarcomas than rates reported for patients with general chondrosarcomas, and local recurrence or metastasis was associated with limited survival. The 5- and 15-year survival probabilities subsequent to diagnosis were 79% and 53%, respectively. The high rates of local recurrence and metastasis likely were caused by the difficult anatomic relationships encountered during scapular resections. This study shows the importance of wide margins which must be achieved to provide local disease control.

Adolescent↗
PubMed2004

Complications and results of arthroplasty for salvage of failed treatment of malignant pathologic fractures of the hip.

The purpose of this study was to evaluate the results and complications of hip arthroplasty done for salvage of failed treatment of pathologic proximal femoral fractures secondary to malignancy. Between 1980 and 2000, 42 patients with a mean age of 63 years were treated with hip arthroplasty to salvage failed treatment of a pathologic proximal femoral fracture. Total hip arthroplasty was done in 16 patients (3 uncemented, 2 hybrid, 11 cemented), and bipolar hemiarthroplasty in 26 (2 uncemented, 24 cemented). A modular, proximal femoral replacement construct was used in 15 patients. Patients were followed a mean of 5.8 years (range, 15 days-20 years). Four hips required reoperation, all for deep infection. Harris Hip score improved from an average of 42 points (range, 17-76 points) preoperatively to an average of 83 points (range, 52-100 points) postoperatively. Most recent radiographs showed femoral component loosening in only one patient. Implant survivorship free of revision for any reason at 5 years was 90% (range, 65-96%) and free of revision for aseptic failure or radiographic failure was 97% (range, 64-99%). Hip arthroplasty is an effective treatment for salvage of failed treatment of pathologic proximal femoral fractures. Modular proximal femoral replacements were often required. The most concerning complication was deep prosthetic infection, which occurred in nearly 10% of this patient population, and in 21% of patients with prior irradiation.

Adult↗
PubMed2004

Long-term results of segmental prosthesis fixation by extracortical bone-bridging and ingrowth.

BACKGROUND: The technique of extracortical bone-bridging and ingrowth fixation with a porous coating over the shoulder region of the implant and augmentation by autogenous bone-grafting was introduced to improve the longevity of implant fixation. The potential advantages of this technique are that new-bone formation across the bone-prosthesis junction may share stress and may prevent osteolysis by sealing off this critical region against the infiltration of wear particles. The objectives of this study were to examine the prevalence of stem-loosening with use of the extracortical bone-bridging and ingrowth technique, the amount of bone formation over the porous-coated region of this prosthesis, and the characteristics of bone formation over the porous-coated region and adjacent bone. METHODS: Forty-three patients who had prosthetic reconstruction with the extracortical bone-bridging and ingrowth technique from 1976 to 1990 were included in this retrospective study. The mean length of follow-up was 9.7 years (range, two to twenty-one years). All but one patient were managed with autogenous bone graft; five, with allograft and autograft; and one, with allograft only. Extracortical bone formation was measured over a 2-cm length of the porous-coated region of the prosthesis in four zones (the medial and lateral aspects on anteroposterior radiographs and the anterior and posterior aspects on lateral radiographs) and was reported as the percentage of the total length (8 cm) covered by extracortical bone with a thickness of >1 mm. The Spearman rank coefficient was used to assess the correlation between pairs of continuous variables. RESULTS: The final average percentage of the porous-coated region that was covered by extracortical bone formation was 76% +/- 34% for all patients and anatomical sites of reconstruction. Use of bone cement was associated with less bone formation (p = 0.04), and this value remained lower at the final measurement (p = 0.06). One stem had aseptic loosening, but no sign of osteolysis was found. The radiographic appearance of the bone formation had stabilized at two years of follow-up. All patients with allograft augmentation had greater bone formation. The amount of extracortical bone formation did not differ in relation to the type of porous coating, anatomical sites, pathological disorder, sex or age of the patient, or length of reconstruction. CONCLUSIONS: As shown by the low prevalence of stem-loosening (two of fifty-six stems or one of forty-three patients), the use of the extracortical bone-bridging and ingrowth fixation technique is associated with improved stem fixation in segmental bone-replacement prostheses applied for limb salvage. In the demanding biomechanical environment and with the risk of stress and particle-related bone resorption, the extracortical bone-bridging and ingrowth fixation is an attractive method to provide long-lasting implant fixation.

Adolescent↗
PubMed2004

Patient survival after hip arthroplasty for metastatic disease of the hip.

BACKGROUND: The hip joint is a common location for metastatic disease. Actual as well as impending fractures at this site are frequently due to mechanical instability after tumor invasion and are usually treated surgically with hip arthroplasty. The objective of this study was to analyze survival and influences on survival after hip arthroplasty for metastatic hip disease. METHODS: Two hundred and ninety-nine patients who had undergone a total of 306 hemiarthroplasty or total hip arthroplasty procedures for treatment of a pathologic or an impending pathologic hip fracture between 1969 and 1996 at our institution were included in this study. Data that had been acquired prospectively within the total joint registry of our institution were reviewed retrospectively. RESULTS: The median duration of survival after the arthroplasty was 8.6 months. The duration of survival was significantly associated with the site of the fracture, location of the primary tumor, and time from the diagnosis of the primary tumor to the surgery for the fracture (p < or = 0.05). The time from the diagnosis to the arthroplasty was a significant independent predictor of survival. CONCLUSIONS: Patients undergoing hip arthroplasty for metastatic disease have a limited life expectancy, with only 40% (120) of the 299 patients in our series still alive at one year after the surgery. By identifying prognostic factors regarding life expectancy, this study provides surgeons and oncologists with information with which to weigh risks and benefits of hip arthroplasty for individual patients preoperatively.

Adult↗
PubMed2004

Effect of granulocyte-stimulating factors on marrow of adult patients with musculoskeletal malignancies: incidence and MRI findings.

OBJECTIVE: Our goal was to determine the incidence and pattern of red marrow reconversion on MRI of adults receiving granulocyte-stimulating factors as part of their chemotherapy regimen for primary musculoskeletal neoplasms and correlate the changes with WBC counts. MATERIALS AND METHODS: Twenty-five adults with soft-tissue sarcomas (n = 15) or primary bone tumors (n = 10) who underwent chemotherapy that included granulocyte-stimulating factors formed the study group. Two radiologists retrospectively evaluated the MRI studies by consensus before and after therapy to determine the presence of changes consistent with red marrow reconversion. Changes were categorized by appearance on T1- and T2-weighted images for location, pattern, and extent of marrow involvement. WBC counts at the time of MRI were recorded. Records were examined for evidence of marrow-infiltrating tumors or metastases. RESULTS: Ten (40%) of the 25 patients underwent bone marrow changes consistent with red marrow reconversion. In seven (70%) of 10 patients, the changes were diffuse in visualized bones and simulated diffuse marrow-infiltrative tumor. In three (30%) of 10 patients, the changes were focal, simulating metastases. T2 signal prolongation was identified in the marrow reconversion in nine patients (90%), although all had shortened T1 signal. Four patients (40%) had elevated WBC counts at the time of the MRI after therapy, but all had shortened T1 signal. Four patients (40%) had elevated WBC counts at the time of the MRI after therapy, five (50%) had normal counts, and one (10%) had a below-normal count. No osseous metastases or marrow-infiltrating tumors were found during follow-up. CONCLUSION: Forty percent of patients showed marrow changes mimicking tumor on MRI that were attributable to red marrow reconversion, which correlated moderately with WBC response.

Adult↗
PubMed2004

Radiologic case study. Gouty tophus involving the distal quadriceps tendon.

This case depicts an unusual presentation of gout, which could be mistaken for sarcoma. The radiographic and MRI findings suggest gout whereas the CT appearance is most specific. Therefore, CT should be considered when MRI demonstrates low to intermediate T2 signal in a heterogeneously enhancing soft-tissue mass around a joint, tendon, or bursa, especially when radiographs show adjacent erosion with a sclerotic margin. Gouty tophus is not excluded by a normal serum uric acid level. Computed tomography or ultrasound can be used to guide needle biopsy to provide diagnostic tissue.

Gout↗
PubMed2004

Dedifferentiated chondrosarcoma: the role of chemotherapy with updated outcomes.

BACKGROUND: There are very few published data on the survival of patients with dedifferentiated chondrosarcoma, or, more specifically, on the efficacy and role of chemotherapy, especially in the era of modern diagnostic and treatment modalities. The current study examines the influence of advancements in imaging and chemotherapy on outcome and serves as an extension to a previous study published in 1986. METHODS: Forty-two patients with dedifferentiated chondrosarcoma who had presented to our institution between 1986 and 2000 were identified, and a retrospective chart review was performed. The study group included twenty-four men and eighteen women with an average age of sixty-six years. The diagnosis of dedifferentiated chondrosarcoma was verified histologically, and data on treatment, adjuvant therapy, and survival were obtained from the medical records of all patients. All patients had been followed for a minimum of twenty-four months. RESULTS: The tumors were classified, according to the system of the Musculoskeletal Tumor Society, as grade IIA (five), grade IIB (twenty-six), and grade III (eleven). Three patients underwent biopsy only, eighteen had a limb-sacrificing procedure, and twenty-one had a limb-sparing procedure. In the group of patients who underwent resection, the surgical margins were classified as intralesional in three, marginal in two, wide in nineteen, and radical in fifteen. Twenty-seven patients received neoadjuvant therapy; of these, twenty-three received chemotherapy only, two received radiotherapy only, and two received combined therapy. The median survival time was 7.5 months, and the five-year rate of disease-free survival was 7.1%. With the numbers available, there was no significant difference in the rate of disease-free survival with respect to the use of chemotherapy (p = 0.54), the location of surgical margins (p = 0.14), the histological subtype (p = 0.87), the tumor stage at the time of diagnosis (p = 0.43), the tumor size (p = 0.79), or the performance of limb-sparing as opposed to limb-sacrificing procedures (p = 0.42). CONCLUSIONS: Despite advances in diagnostic modalities and adjuvant therapies, dedifferentiated chondrosarcoma continues to carry a poor prognosis. While local control is achieved in the majority of cases, distant disease remains the greatest clinical challenge, developing in 90% of patients. Efforts are needed to continue to encourage earlier diagnosis and to develop effective adjuvant therapies for the control of distant disease. The routine use of current adjuvant chemotherapy and its inherent risks in this population should be reconsidered.

Adult↗
PubMed2003

Complications in long-term survivors of Ewing sarcoma.

BACKGROUND: Multimodality treatment has dramatically improved the outcome of patients with Ewing sarcoma. However, there appears to be little information concerning treatment-related complications in patients who are long-term survivors. METHODS: Forty-one patients with Ewing sarcoma who were treated between 1960-1980 and who survived the disease by at least 20 years were included in the current study. In a retrospective analysis, all complications related to the multimodality treatment of Ewing sarcoma were assessed. RESULTS: The patient group was comprised of 17 men and 24 women, with a mean age at the time of presentation of 16.8 years (range, 5-51 years). Approximately 20% of the lesions were located in the pelvis. All but 9 patients (78%) received chemotherapy as part of their treatment. The overall follow-up period averaged 25 years (range, 20-36 years). All except 1 patient were alive at the time of final follow-up, with the latter patient dying of radiation-induced secondary malignancy after 33 years. Only 17 patients (41%) were found to be free of any complication. These included metastases, local recurrence, secondary malignancies, pathologic fractures, and radiation-associated and chemotherapy-associated morbidities. CONCLUSIONS: Although the patients in the current study were treated successfully in terms of surviving an aggressive tumor, the high complication rate in this group of long-term survivors is noteworthy and indicates that long-term follow-up should be mandatory.

Adolescent↗
PubMed2003

Foot malignancies: a multidisciplinary approach.

Malignant osseous and soft tissue tumors of the foot are rare and should be considered in patients who have foot-related symptoms. Most sarcomas affect patients who are older than 55 years; however, many young patients who are otherwise healthy, may present with malignant foot and ankle lesions. In addition to benign and malignant neoplasms, pseudotumorous conditions mimic neoplastic lesions and should be differentiated before any treatment is undertaken. Invasiveness is a characteristic of sarcomas. The foot is a terminal anatomic structure, with closed and tight compartments and well-vascularized tissues, that predispose it to hematogenous and lymphatic metastases. Patients who have a malignant foot tumor should be referred to an orthopedic oncologist for further evaluation and treatment. The goals of treatment include local tumor control, restoration of function and stability during standing and walking, long-term survival, and improved quality of life. In most cases, wide surgical margins require a ray, Syme, midtarsal, or below-the-knee amputation. Recent advances in chemotherapy and radiotherapy have allowed limb salvage procedures with wide tumor resections. Because overall survival is greatly improved in these patients, the reconstruction of skeletal defects needs to be more functional and durable. After tumor resection, reconstruction of the skeletal and soft tissue defects is possible by using bone allografts or vascularized autografts, arthrodesis, and free vascularized musculocutaneous flaps.

Bone Neoplasms↗
PubMed2003

Secondary chondrosarcoma in osteochondroma: report of 107 patients.

Secondary chondrosarcomas are rare; recognition and diagnosis are difficult. Slow growth and late recurrence require long-term followup to understand the clinical course. In the current study, 107 patients had secondary chondrosarcoma arising in a solitary osteochondroma (61 patients) or multiple exostoses (46 patients). All histologic slides were reviewed without knowledge of the outcome, and radiologic studies were available for review in 71 cases. Patients with secondary chondrosarcoma were one to two decades younger than those with primary chondrosarcoma. Male preponderance and a predilection for flat bones were observed. The radiologic signs of sarcomatous degeneration included irregularity of the margin, inhomogeneous mineralization, and an associated soft tissue mass. The tumors generally were well-differentiated. Only 10 tumors were classified as Grade 2. Five-year and 10-year local recurrence rates were 15.9% and 17.5%, respectively, and 5- and 10-year mortality rates were 1.6% and 4.8% for patients having initial treatment at the authors' institution. Metastasis developed in five patients: in the lung in four patients and in the groin region in one patient. Most patients who died of tumor died of local recurrence. Wide excision had the lowest local recurrence rate. With successful surgical treatment, patients may have long-term disease-free survival.

Adolescent↗
PubMed2003

Advances and challenges in the surgical treatment of metastatic bone disease.

There are numerous challenges facing the orthopaedic surgeon who treats metastatic bone disease in the twenty-first century. The orthopaedic surgeon must be familiar with the indications for surgical intervention, the available implants for fixation of a given anatomic lesion, the appropriateness of fixation versus resection and replacement, and the viability of newer, less invasive treatment options for a given lesion. Determination of the best surgical candidates still is controversial, especially in the arena of prophylactic treatment. Recent advances have made fixation with intramedullary devices and standard plates simpler and more rigid. The advent and improvement of megaprostheses has made complex joint reconstructions more durable. Advances in interventional radiology such as radiofrequency ablation and percutaneous vertebroplasty and acetabuloplasty with polymethylmethacrylate (PMMA) continue to be promising options for future treatment. Better methods are necessary to evaluate the status of the patients preoperatively and postoperatively, to classify functional improvement after surgical treatment, and to determine the impact of treatment on the quality of life.

Acetabulum↗
PubMed2003

Pathologic fracture as a complication in the treatment of Ewing's sarcoma.

The purpose of the current study was to define the outcome of patients with Ewing's sarcoma who sustained a fracture either at initial presentation or subsequent to multimodal treatment, and to identify parameters that may influence the treatment of these patients. The age of the 21 males and 14 females who sustained a fracture during the treatment for Ewing's sarcoma averaged 15 years (range, 4-30 years) at diagnosis. Fourteen patients presented with a pathologic fracture, whereas 21 patients had a fracture develop subsequent to the initial treatment at a mean of 4 years (range, 1-19 years). The femur was the most common location (50%). At a mean followup of 10 years (range, 1-33 years), 21 of 35 patients (60%) were alive and free of disease. There was no local recurrence, but there was one postradiation sarcoma associated with the fracture. Comparing the followup of patients who sustained the fracture at presentation with the followup of patients who subsequently had a fracture, no statistically significant difference was found (117 months versus 124 months). Overall, pathologic fracture in association with Ewing's sarcoma does not seem to be a negative prognostic parameter with respect to survival in this series. Therefore, a fracture at presentation may not mandate amputation. However, it occurs frequently subsequent to initial multimodal treatment because of delayed fracture healing. Because conservative or minimal osteosynthesis have high failure rates, more aggressive resection and reconstruction have to be considered carefully.

Adolescent↗