Efficacy of Pre- and Postoperative Chemotherapy in Patients with Osteosarcoma of the Extremities

Loading comparison of two structures in the moving tube of a non-invasive prosthesis

BACKGROUND

The treatment of adolescent patients with distal femoral cancer has always been a concern. The limb-salvage, regarded as a mainstream treatment, had been developed in recent years, but its application in children still remains challenging. This is because it can lead to potential limb-length discrepancy from the continued normal growth of the contralateral lower body. The extendable prosthesis could solve this problem. The principle is that it can artificially control the length of the prosthesis, making it consistent with the length of the side of the lower limbs. However, this prosthesis has some complications. The extendable prosthesis is classified into invasive and minimally invasive, which extends the prosthesis with each operation.

OBJECTIVE

We designed a new non-invasive prosthesis that can be extended in the body. Based on the non-invasive and extendable characteristics, we need to verify the supporting performance of this prosthesis.

METHODS

We carried out a mechanical testing method and finite element analysis simulation.

CONCLUSION

The support performance and non-invasively extension of this prosthesis were verified.

The multidisciplinary treatment of osteosarcoma of the proximal tibia: a retrospective study

Background

Survival and reconstruction constitute important challenges in multimodal treatment of osteosarcoma of the proximal tibia. The purpose of this study was to assess the efficacy and prognosis of neoadjuvant chemotherapy and custom-designed endoprosthetic arthroplasty.

Methods

A total of 69 patients with osteosarcoma of the proximal tibia were evaluated, including 43 males and 26 females, treated with multidisciplinary limb-salvage remedy from October 2003 to December 2013. They were at least 12 years old (mean, 20 years; range, 12–57 years). The gap between tumor and main artery/nerve was showed in MRI. Mean follow up was 69.5 months (range, 9–144 months). Kaplan-Meier survival curves were generated to assess prognosis and relapse rate. The initial symptoms and disease duration for each patient were recorded. Correlation analyses were performed for the association of various parameters with prognosis. Functional outcomes were evaluated using the Musculoskeletal Tumor Society (MSTS) guidelines after 6 months postoperatively, to analyze the relation between bone excision size and function recovery.

Results

The resection lengths measured intraoperatively ranged from 80 to 230 mm, and contained 3 cm of normal bone around the tumor. A total of 3 courses of preoperative chemotherapy were administered to all cases. At final follow-up, 1 case showed recurrence. Meanwhile, 8 patients (11.6%) died from lung metastasis. Post-operative infection occurred in 3 patients; 1 case was maintained with revision surgery. Two cases underwent amputation. The mean MSTS system score was 21.6.

Conclusions

The multidisciplinary treatment result in an overall positive outcome, with improved function.

Expression change of ezrin as a prognostic factor in primary osteosarcoma

Osteosarcoma is a life-threatening malignancy that most often occurs in teenagers. Ezrin is a cytoskeleton linker protein that is actively involved in the metastatic capacity of cancer cells. In this study, we investigated the expression change of ezrin after preoperative chemotherapy and its prognostic value in patients with primary osteosarcoma. Ezrin mRNA expression level of initial biopsy specimens and resected tumor specimens after preoperative chemotherapy of 25 patients who had primary osteosarcoma with ezrin expression was detected by semiquantitative reverse transcription polymerase chain reaction (RT-PCR) to evaluate the expression change of ezrin. In addition, the prognostic factors and the relationship between the expression change of ezrin and the clinical characteristics were analyzed. Expression change of ezrin was found in 64% of all 25 patients. The expression change of ezrin had good relation with histology (P = 0.037), grade (P = 0.006), chemotherapy response (P = 0.017), and metastasis or recurrence (P = 0.041). The 2-year overall survival and event-free survival were associated with expression change of ezrin (P = 0.001 and P = 0.002, respectively) and response to preoperative chemotherapy (P = 0.001 and P = 0.012, respectively). Our findings suggest that expression change of ezrin is an independent positive prognostic factor in non-metastatic osteosarcoma.

Clinical value of ezrin expression in primary osteosarcoma

PURPOSE

Ezrin is a membrane cytoskeletal linker protein and it is known to be associated with metastasis of primary osteosarcoma. The aim of this study is to determine the relationship between an ezrin expression and several key clinical parameters and to elucidate its potential prognostic value for patients with osteosarcoma.

MATERIALS AND METHODS

Seventy patients with histologically confirmed osteosarcoma and who had no distant metastasis were enrolled between 1995 and 2005 at Yonsei Cancer Center, Severance Hospital, Korea. The clinical parameters were retrospectively reviewed and immunohistochemical staining (IHC) for ezrin was performed using the surgically resected specimens.

RESULTS

Of the 70 tumor specimens, 39 (55.7%) revealed an ezrin expression. More of an osteoblastic histology and an elevated initial ALP level were observed in the ezrin positive patients than in the ezrin negative patients (p=0.008 and 0.001, respectively). The proportion of patients who favorably responded to neoadjuvant chemotherapy (≥or=90% necrosis) was significantly higher in the group of ezrin positive patients than that in the group of ezrin negative patient (72.2% vs 45.2%, respectively, p=0.024). The ezrin positive patients showed more frequent recurrence than did the ezrin negative patients (64.1% vs 35.5%, respectively, p=0.017). The patients with an ezrin expression also demonstrated poorer survival than did those patients without ezrin expression (5-year EFS: 31.7% vs 61.3%, respectively, p=0.023, 5-year OS: 53.4% vs 71.0%, respectively, p=0.022). When comparing EFS according to both an ezrin expression and chemoresponsiveness, there were trends that the ezrin negative/chemoresponsive group showed the best 5-year EFS (71.4%), followed by the ezrin negative/chemoresistant group (52.9%), the ezrin positive/chemoresponsive group (38.1%) and the ezrin positive/chemoresistant group (13.6%). These trends were statistically significant (p=0.036).

CONCLUSION

The expression of ezrin by IHC staining was found in 55.7% of the patients with metastasis-free osteosarcoma. Immunoreactivity to ezrin is a negative prognostic factor for survival for the patients suffering with osteosarcoma. Identifying an ezrin expression might offer a valuable piece of information when treating patients with primary osteosarcoma.

Carboxypeptidase-G2 rescue in a patient with high dose methotrexate-induced nephrotoxicity

A 13 year-old girl with osteosarcoma and pulmonary tumor recurrence developed acute renal failure following high dose methotrexate (12 g/m(2)) therapy, she had previously tolerated high dose methotrexate and her renal and hepatic functions were normal. Briefly, 48 hours after beginning methotrexate infusion her methotrexate concentration and creatinine level were 1338.8 microM/L and 5.8 mg/dl, respectively. Grade IV oral mucositis and neutropenia with fever developed at 144 hours after MTX infusion. Hydration and alkalinization were continued and leucovorin rescue was intensified based on the plasma MTX concentrations. Plasma exchange was performed twice and hemodialysis 3 times without problems, but methotrexate and creatinine levels remained high, 91.9 microM/L, and 2.5 mg/dl, respectively. After 3 courses of hemodialysis carboxypeptidase-G2 (CPDG2) was administered at 50 U/kg, intravenously over 5 minutes. After 15 minutes of CPDG2 (Voraxaze) infusion, her plasma MTX concentration was 0.91 microM/L and no rebound elevation or side effects developed. Thirteen days post-MTX infusion her renal function had normalized. We report here our experience of a dramatic methotrexate level reduction caused by CPDG2 administration.