Hwan Seong Cho

Unicameral bone cysts

Open surgery is rarely justified for the initial treatment of a unicameral bone cyst, but there is some debate concerning the relative effectiveness of closed methods. This study compared the results of steroid injection with those of autologous bone marrow grafting for the treatment of unicameral bone cysts. Between 1990 and 2001, 30 patients were treated by steroid injection and 28 by grafting with autologous bone marrow. The overall success rates were 86.7% and 92.0%, respectively (p>0.05). The success rate after the initial procedure was 23.3% in the steroid group and 52.0% in those receiving autologous bone marrow (p<0.05), and the respective cumulative success rates after second injections were 63.3% and 80.0% (p>0.05). The mean number of procedures required was 2.19 (1 to 5) and 1.57 (1 to 3) (p<0.05), the mean interval to healing was 12.5 months (4 to 32) and 14.3 months (7 to 36) (p>0.05), and the rate of recurrence after the initial procedure was 41.7% and 13.3% in the steroid and in the autologous bone marrow groups, respectively (p<0.05). Although the overall rates of success of both methods were similar, the steroid group had higher recurrence after a single procedure and required more injections to achieve healing.

Joint-preserving limb salvage surgery under navigation guidance.

Recently, the navigation system has been introduced to orthopedic oncology. It can apply MRI and/or CT images to intraoperative visualization. We performed navigation‐assisted limb salvage surgeries on patients with a malignant bone tumor of the metaphysis of the long bone or the iliac bone while preserving the adjacent joint.

Computer-Assisted Sacral Tumor Resection: A Case Report

Resection of sacral tumors is one of the most difficult operations in orthopaedic oncology because complex anatomy and important internal organs in the pelvic area make it difficult to achieve wide surgical margins1. Wide resection of sacral tumors may lead to serious functional impairments due to injury to important internal organs and/or the lumbosacral nerve roots or through the disruption of load-bearing through the sacroiliac joint. Recent advances in diagnostic modalities facilitate better surgical planning and can help in the performance of surgeries as planned. Computer-assisted surgery has been used in orthopaedic operations such as cruciate ligament reconstruction, hip and knee arthroplasty, and pedicle screw placement. The main advantage of computer-assisted navigation over other imaging modalities is that intraoperative identification can increase the accuracy of surgical resection. We report a case of sacral chondrosarcoma in which computer-assisted surgery provided intraoperative real-time imaging, thereby allowing us to achieve adequate surgical margins while preserving the sacral nerve roots. Additionally, the tumor resection was carried out through a posterior approach only. The patient was informed that data concerning the case would be submitted for publication, and he consented. A fifty-two-year-old man was referred to us with a longer than five-month history of a dull pain in the lower back. There was no evidence of a neurologic deficit in the lumbosacral nerve roots. Systemic symptoms, such as fever or weight loss, were absent. Plain radiographs of the pelvis showed an osteolytic lesion at the right sacral ala. Magnetic resonance imaging revealed that the tumor was located in the right sacral ala, between the sacroiliac joint and the first and second sacral foramina (Fig. 1). Computed tomography revealed cortical destruction of the sacral side of the sacroiliac joint, but there was no evidence of involvement of the ilium. Further evaluation, including computed tomography …

Outcome after Surgical Treatment of Pelvic Sarcomas

Background We present here the oncological and functional outcomes of limb salvage with or without reconstruction for primary sarcomas in the pelvic bone. Methods Forty-four patients who underwent pelvic resection for primary sarcomas involving the pelvis were reviewed. The average follow-up period was 39 months (range, 0 to 146 months). Chondrosarcoma (n = 17) and osteosarcoma (n = 10) were the most common diagnoses. Various clinicopathologic factors were analyzed in relation to the oncological outcomes of overall survival and local recurrence. The Musculoskeletal Tumor Society functional scores and complications were compared according to the tumor location, pelvic continuity and the type of resection. Results The overall 5-year survival rate was 40%. Metastasis at the time of diagnosis, the surgical margin and the histologic grade were the independent prognostic factors for survival. The surgical margin was an independent prognostic factor for local recurrence. An ischiopubic location of the tumor, restoration of pelvic continuity and hip joint reconstruction with total hip replacement arthroplasty were related with higher functional scores. Complications occurred in 50% of the patients and the complications varied according to the tumor location with infection being the most common complication. Conclusions Achieving an adequate surgical margin is necessary for improving the oncological outcome of pelvic sarcomas. Restoration of the pelvic continuity and the hip joint improves the functional outcome. However, complications are common and so careful selection of the reconstruction method is needed.

Management of Eosinophilic Granuloma Occurring in the Appendicular Skeleton in Children

Background We compared indomethacin therapy with the more aggressive approaches of anti-cancer chemotherapy and surgery in the treatment of isolated Langerhans cell histiocytosis (LCH) of bone in children. Methods Comparisons were made with respect to healing of the lesion without recurrence, time to radiological healing of the lesion, time to functional recovery, and complications related to treatment. Results Complete radiologic healing of the lesion (mean, 15.3 months) and functional recovery (mean, 5.6 months) were observed in all patients treated with either approach. No significant differences were noted in the time to complete radiologic healing or the time to functional recovery between the two groups. There were no recurrences with either approach until the last follow-up (mean, 56 months). Complications were common with anti-cancer chemotherapy, but indomethacin was well-tolerated. Conclusions Indomethacin seems to be effective for treating isolated LCH of bone in children. Hence, morbidities associated with aggressive treatment approaches such as anti-cancer chemotherapy or surgery can be avoided.

Minimal invasive surgery for unicameral bone cyst using demineralized bone matrix: a case series

BackgroundVarious treatments for unicameral bone cyst have been proposed. Recent concern focuses on the effectiveness of closed methods. This study evaluated the effectiveness of demineralized bone matrix as a graft material after intramedullary decompression for the treatment of unicameral bone cysts.MethodsBetween October 2008 and June 2010, twenty-five patients with a unicameral bone cyst were treated with intramedullary decompression followed by grafting of demineralized bone matrix. There were 21 males and 4 female patients with mean age of 11.1 years (range, 3–19 years). The proximal metaphysis of the humerus was affected in 12 patients, the proximal femur in five, the calcaneum in three, the distal femur in two, the tibia in two, and the radius in one. There were 17 active cysts and 8 latent cysts. Radiologic change was evaluated according to a modified Neer classification. Time to healing was defined as the period required achieving cortical thickening on the anteroposterior and lateral plain radiographs, as well as consolidation of the cyst. The patients were followed up for mean period of 23.9 months (range, 15–36 months).ResultsNineteen of 25 cysts had completely consolidated after a single procedure. The mean time to healing was 6.6 months (range, 3–12 months). Four had incomplete healing radiographically but had no clinical symptom with enough cortical thickness to prevent fracture. None of these four cysts needed a second intervention until the last follow-up. Two of 25 patients required a second intervention because of cyst recurrence. All of the two had a radiographical healing of cyst after mean of 10 additional months of follow-up.ConclusionsA minimal invasive technique including the injection of DBM could serve as an excellent treatment method for unicameral bone cysts.

Unplanned excision of soft tissue sarcoma: The impact of the referring hospital

BACKGROUND Unplanned excision of soft tissue sarcoma (STS) remains a common problem performed at various levels of hospitals, where clinical characteristics may differ. However, there is little literature describing the impact of the referring hospital on patient characteristics and/or outcome in unplanned excision of STS. This study examined the possible different patient characteristics and prognoses according to the level of referring hospitals where unplanned excision was performed. METHODS Patients referred to our institute after unplanned excision of STS on their extremities were reviewed. Referring hospitals were categorized into two groups according to their referral grades; tertiary hospitals (general hospitals with tertiary [highest] referral grade, n = 42) and non-tertiary hospitals (others, n = 79). RESULTS Patients referred from tertiary hospitals had significantly larger number of high-grade tumors (p = 0.019) but lower chance of finding a residual tumor at re-excision (p = 0.020) than non-tertiary hospitals. For oncological outcomes, referral from tertiary hospital was an independent factor for better local control (hazard ratio, 0.211; 95% confidence interval, 0.061-0.730). However, there was no difference in disease-specific death (p = 0.729) or metastasis (p = 0.978) between the two groups. CONCLUSIONS Despite having worse clinicopathologic characteristics, patients referred from tertiary hospitals had fewer local recurrences than patients from non-tertiary hospitals. The impact of the referring hospital on patient outcome and disease characteristics needs to be considered in unplanned excision of STS.

Survival of patients with skeletal metastases from hepatocellular carcinoma after surgical management

Skeletal metastases from hepatocellular carcinoma are highly destructive vascular lesions which severely reduce the quality of life. Pre-existing liver cirrhosis presents unique challenges during the surgical management of such lesions. We carried out a retrospective study of 42 patients who had been managed surgically for skeletal metastases from hepatocellular carcinoma affecting the appendicular skeleton between January 2000 and December 2006. There were 38 men and four women with a mean age of 60.2 years (46 to 77). Surgery for a pathological fracture was undertaken in 30 patients and because of a high risk of fracture in 12. An intralesional surgical margin was achieved in 36 and a wide margin in six. Factors influencing survival were determined by univariate and multivariate analyses. The survival rates at one, two and three years after surgery were 42.2%, 25.8% and 19.8%, respectively. The median survival time was ten months (95% confidence interval 6.29 to 13.71). The number of skeletal metastases and the Child-Pugh grade were identified as independent prognostic factors by Cox regression analysis. The method of management of the hepatocellular carcinoma, its status in the liver, the surgical margin for skeletal metastases, the presence of a pathological fracture and adjuvant radiotherapy were not found to be significantly related to the survival of the patient, which was affected by hepatic function, as represented by the Child-Pugh grade.

Capsaicin induces apoptosis in MG63 human osteosarcoma cells via the caspase cascade and the antioxidant enzyme system

Osteosarcoma is the most common malignant bone tumor in children and adolescents. This aggressive cancer mostly occurs in the long bones. Therefore, novel therapeutic approaches, such as biological therapies and gene therapy, are required to efficiently treat osteosarcoma. Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) has been demonstrated to inhibit the growth of several types of cancer cells and a number of studies have shown that osteosarcoma may be vulnerable to biological therapies. However, little is known regarding the therapeutic effects of capsaicin on osteosarcoma. This study investigated the effects of capsaicin on MG63 human osteosarcoma cells, in addition to elucidating the regulatory signaling pathways underlying the effects of capsaicin, the caspase cascade and the antioxidant enzyme system. The MG63 cell line was treated with various concentrations of capsaicin. Cells were analyzed using MTT and flow cytometry, and the presence of DNA fragmentation was evaluated using TUNEL assay. Results showed capsaicin induced apoptosis in MG63 cells. Thus, capsaicin exhibited an anticancer effect in osteosarcoma cells.

Role of integrin-linked kinase in osteosarcoma progression

Although integrin‐linked kinase (ILK) has been suggested to play a role in the tumorigenesis of a number of human epithelial carcinomas, little is known of its role in musculoskeletal sarcoma. The authors studied ILK expression by immunohistochemistry using osteosarcoma prechemotherapy specimens from 56 patients, and investigated the prognostic implications of the findings obtained. It was found that ILK overexpression was significantly correlated with the presence of distant metastasis (p = 0.008) and that it was an independent prognostic factor for both poor overall survival and poor event‐free survival (p = 0.015 and 0.010, respectively). During a transfection experiment conducted by transfecting osteosarcoma cells with ILK siRNA, VEGF concentrations were measured using an ELISA kit, and then compared with those of untransfected controls to evaluate its angiogenic effects. In addition, apoptotic percentages were measured by Annexin‐V flow cytometry, and invasive properties were evaluated by measuring the numbers of non‐migrating cells in a Boyden chamber. It was found that ILK downregulation significantly decreased angiogenesis, increased apoptosis, and decreased invasiveness of osteosarcoma cells. These results show that ILK is a promising prognostic factor in osteosarcoma and a novel potential therapeutic target for the treatment of osteosarcoma.