We performed multiple drilling as a femoral head-preserving procedure for osteonecrosis of the femoral head thinking the therapeutic effects of core decompression could be achieved by this simpler procedure than core decompression. We retrospectively reviewed 136 patients (163 hips) who had multiple drilling using 9/64-inch Steinmann pins for treatment of nontraumatic osteonecrosis of the femoral head. The mean followup for patients who did not require additional surgery (113 hips) was 87 months (range, 60-134 months). We defined failure as the need for additional surgery or a Harris hip score less than 75. After a minimum 5-year followup, 79% (31/39) of patients with Stage I disease and 77% (62/81) of patients with Stage II disease had no additional surgery. All (15/15) small lesions (<25% involvement) and 84% (37/44) of medium-sized lesions (25-50% involvement) were considered successful. Survival rates of patients with Ficat Stages I or II lesions were greater than survival rates for patients with Stage III lesions. Hips with a large necrotic area had poor results. We had one instance of subtrochanteric fracture through drill entry holes. Multiple drilling is straightforward with few complications and produces results comparable to results of other core decompression techniques.

Response to neoadjuvant chemotherapy is a significant prognostic factor for osteosarcoma; however, this information can be determined only after surgical resection. If we could predict histologic response before surgery, it might be helpful for the planning of surgeries and tailoring of treatment. We evaluated the usefulness of 18 F-FDG PET for this purpose. Methods: A total of 70 consecutive patients with a high-grade osteosarcoma treated at our institute were prospectively enrolled. All patients underwent 18 F-FDG PET and MRI before and after neoadjuvant chemotherapy. We analyzed the predictive values of 5 parameters, namely, maximum standardized uptake values (SUVs), before and after (SUV2) chemotherapy, SUV change ratio, tumor volume change ratio, and metabolic volume change ratio (MVCR) in terms of their abilities to discriminate responders from nonresponders. Results: Patients with an SUV2 of less than or equal to 2 showed a good histologic response, and patients with an SUV2 of greater than 5 showed a poor histologic response. The histologic response of a patient with an intermediate SUV2 (2 , SUV2 # 5) was found to be predictable using MVCR. A patient with an MVCR of less than 0.65 is likely to be a good responder, whereas a patient with an MVCR of greater than or equal to 0.65 is likely to be a poor responder. According to our model, the predictive values for good responders and poor responders were 97% (31/32) and 95% (36/38), respectively. Conclusion: We found that combined information on 18 F-FDG PET and MRI scans, acquired before and after chemotherapy, could be used to predict histologic response to neoadjuvant chemotherapy in osteosarcoma.

We devised a nomogram for nonmetastatic osteosarcoma that proposes improved estimates of metastasis over AJCC staging system or tumor necrosis rate. We suggest that this nomogram allows individualized risk assessments and could be used as the basis for risk-adapted therapy.

We evaluated the potential of 18 F-FDG PET/CT and diffusionweighted imaging (DWI) to monitor the histologic response in patients with extremity osteosarcoma receiving neoadjuvant chemotherapy, using sequential PET/CT and MR imaging. Methods: We prospectively registered 28 patients with high-grade osteosarcoma treated with 2 cycles of neoadjuvant chemotherapy and surgery. All patients underwent sequential 18 F-FDG PET/CT and MR imaging before (PET/MR1) and after neoadjuvant chemotherapy (PET/MR2). Maximum standardized uptake value (SUV), tumor volume based on MR imaging (MRV), and the mean apparent diffusion coefficient (ADC) values were measured on PET/MR1 (SUV1, MRV1, and ADC1) and PET/MR2 (SUV2, MRV2, and ADC2). The percentage changes in maximum SUV (ΔSUV), MRV (ΔMRV), and ADC (ΔADC) were calculated, and the correlations among these parameters were evaluated. After surgery, the effects of neoadjuvant chemotherapy were graded histopathologically: grades III and IV (necrosis of $ 90%) indicated a good response, and grades I and II (necrosis of , 90%) indicated a poor response. The optimum cutoff values of ΔSUV, ΔMRV, ΔADC, and their combination for predicting histologic response were assessed by single-and multi-receiver-operating-characteristic curve analysis. Results: Twenty-seven patients were enrolled in the present study after 1 patient with inadequate acquisition of MR imaging was excluded. ΔSUV and ΔADC negatively correlated with each other (r 5 20.593, P 5 0.001), and ΔMRV did not correlate with ΔSUV or ΔADC. The cutoff value, sensitivity, specificity, and accuracy for predicting good histologic response were # 252%, 67%, 87%, and 78%, respectively, for ΔSUV and . 13%, 83%, 73%, and 78%, respectively, for ΔADC. However, ΔMRV did not predict histologic response. Sensitivity, specificity, and accuracy were 83%, 87%, and 85%, respectively, using the combined criterion of ΔSUV # 231% and ΔADC . 13%. Conclusion: In the current preliminary study, both PET/CT and DWI are useful for predicting histologic response after neoadjuvant chemotherapy in osteosarcoma. Combining PET/CT and DWI may be an effective method to predict the histologic response of patients to neoadjuvant chemotherapy.

The RANKL-RANK-OPG axis might be a promising target for the treatment of osteosarcoma, but further studies are needed to verify our data in a larger cohort.

The necrosis rate adjusted by the tumor volume change is an independent prognostic factor in osteosarcoma. This adjusted tumor necrosis rate may serve as a basis for risk-adapted therapy in combination with other prognostic factors.

PET/CT is more sensitive and accurate than BS for diagnosing bone metastases in osteosarcoma. The combined use of PET/CT and BS improves sensitivity.

The clinical impact of postoperative deep infection on survival remains controversial in osteosarcoma patients. The authors identified 31 osteosarcoma patients that developed a deep infection within 1 year of operation between 1990 and 2003, and compared clinicopathologic characteristics of 31 patients that developed an infection with those of 316 patients that did not. For survival analysis, 62 noninfected patients matched for prognostic factors such as histologic response, tumor size, and location were also selected. In infected patients, although it was not significant due to the small patient numbers, good response to preoperative chemotherapy and a proximal tibial location were frequently observed. No local recurrence developed in infected patients. Five-year overall and metastasis-free survival rates for the 31 infected patients were as high as 89% and 73%, respectively. However, after matching for clinical factors, no survival difference was noted between infected and noninfected patients. Deep infection has a multifaceted effect on patients. However, the present study suggests that the reported positive effect on survival is likely to be related to the clinical characteristics of infected patients rather than an antitumor effect due to the infection. Further investigations are needed to clarify the precise effects of infection.