Does the Clinical Presentation of Secondary Osteosarcoma in Patients Who Survive Retinoblastoma Differ From That of Conventional Osteosarcoma and How Do We Detect Them?

BACKGROUND: Osteosarcoma is the most common secondary malignancy among survivors of retinoblastoma. Most previous reports on secondary malignancy of retinoblastoma included all types of secondary malignancies without a focus on osteosarcoma, owing to its rarity. In addition, there are few studies suggesting tools for regular surveillance for early detection. QUESTIONS/PURPOSES: (1) What are the radiologic and clinical characteristics of secondary osteosarcoma after retinoblastoma? (2) What is the clinical survivorship? (3) Is a radionuclide bone scan a reasonable imaging modality for early detection in patients with retinoblastoma? METHODS: Between February 2000 and December 2019, we treated 540 patients for retinoblastoma. Twelve patients (six male, six female) subsequently developed an osteosarcoma in the extremities; two of these patients had two sites of osteosarcoma (10 femurs, four tibiae) . A Technetium-99m bone scan image was examined annually in all patients for regular surveillance after the treatment of retinoblastoma as per our hospital's policy. All patients were treated with the same strategy as that used for primary conventional osteosarcoma, namely neoadjuvant chemotherapy, wide excision, and adjuvant chemotherapy. The median follow-up period was 12 years (range 8 to 21 years). The median age at the time of diagnosis of osteosarcoma was 9 years (range 5 to 15 years), and the median interval from retinoblastoma diagnosis to osteosarcoma diagnosis was 8 years (range 5 to 15 years). Radiologic characteristics were assessed with plain radiographs and MRI, while clinical characteristics were assessed through a retrospective review of medical records. For clinical survivorship, we evaluated overall survival, local recurrence-free survival, and metastasis-free survival. We reviewed the results of bone scans and clinical symptoms at the time of diagnosis for osteosarcoma after retinoblastoma. RESULTS: In nine of 14 patients, the tumor had a diaphyseal center, and five of the tumors were located at the metaphysis. The femur was the most common site (n = 10), followed by the tibia (n = 4). The median tumor size was 9 cm (range 5 to 13 cm). There was no local recurrence after surgical resection of the osteosarcoma, and the 5-year overall survival rate after the diagnosis of osteosarcoma was 86% (95% CI 68% to 100%). In all 14 tumors, the Technetium bone scan showed increased uptake in the lesions. Ten of 14 tumors were examined in clinic because of patient complaints of pain in the affected limb. Four patients showed no clinical symptoms detected by abnormal uptake on bone scan. CONCLUSION: For unclear reasons, secondary osteosarcomas in patients who were alive after the treatment of retinoblastoma had a slight predilection for the diaphysis of the long bone compared with patients with spontaneous osteosarcoma in other reports. The clinical survivorship of osteosarcoma as a secondary malignancy after retinoblastoma may not be inferior to that of conventional osteosarcoma. Close follow-up with at least yearly clinical assessment and bone scans or other imaging modalities appears to be helpful in detecting secondary osteosarcoma after the treatment of patients with retinoblastoma. Larger multi-institutional studies will be needed to substantiate these observations.Level of Evidenc e Level IV, therapeutic study.

Does reverse total shoulder arthroplasty with allograft-prosthesis composite (APC) have surgical benefits over hemiarthroplasty with APC in patients with tumors of the proximal humerus?

BACKGROUND: The research on surgical outcomes of hemiarthroplasty and reverse total shoulder arthroplasty using allograft-prosthesis composites for the proximal humeral oncologic condition is still scarce. Therefore, this study aimed to compare surgical outcomes of shoulder joint reconstruction with hemiarthroplasty and reverse total shoulder arthroplasty using allograft-prosthesis composites for tumors of the proximal humerus. METHODS: Eleven patients underwent hemiarthroplasty or reverse total shoulder arthroplasty using allograft-prosthesis composites for tumors of the proximal humerus between July 2011 and April 2018 were reviewed. Radiographic analysis for bone union of allograft-host bone junction, implant loosening, stress shielding and shoulder dislocation or subluxation was performed. Functional outcomes were evaluated using visual analog scales for pain, range of motion, Simple Shoulder Test score and Musculoskeletal Tumor Society score. Furthermore, oncologic outcome and complications were also assessed, respectively. RESULTS: There were five patients with hemiarthroplasty (mean age, 23.2 years) and six patients with reverse total shoulder arthroplasty (mean age, 46.8 years, P = 0.05). Radiographically, there were no events associated with implant loosening, stress shielding and shoulder dislocation or subluxation in the two groups. There were no differences in functional outcomes between the two groups. There was no local recurrence in entire cohort. In the hemiarthroplasty group, one patient was required revision surgery to reverse total shoulder arthroplasty at postoperative 6 years due to rotator cuff dysfunction. In the reverse total shoulder arthroplasty group, one patient showed the fracture occurred at allograft-host bone junction at postoperative 6 months. CONCLUSIONS: Surgical outcomes of hemiarthroplasty with allograft-prosthesis composites were not inferior to reverse total shoulder arthroplasty when applied in properly selected patients. The authors recommended that hemiarthroplasty with allograft-prosthesis composites could be used for young age patients without glenoid metastasis involvement, and reverse total shoulder arthroplasty with allograft-prosthesis composites could be used for patients with old age or metastatic bone tumors.

Does the modified Glasgow Prognostic Score aid in the management of patients undergoing surgery for a soft-tissue sarcoma? : an international multicentre study.

AIMS: The modified Glasgow Prognostic Score (mGPS) uses preoperative CRP and albumin to calculate a score from 0 to 2 (2 being associated with poor outcomes). mGPS is validated in multiple carcinomas. To date, its use in soft-tissue sarcoma (STS) is limited, with only small cohorts reporting that increased mGPS scores correlates with decreased survival in STS patients. METHODS: This retrospective multicentre cohort study identified 493 STS patients using clinical databases from six collaborating hospitals in three countries. Centres performed a retrospective data collection for patient demographics, preoperative blood results (CRP and albumin levels and neutrophil, leucocyte, and platelets counts), and oncological outcomes (disease-free survival, local, or metastatic recurrence) with a minimum of two years' follow-up. RESULTS: We found that increased mGPS, tumour size, grade, neutrophil/lymphocyte ratio, and disease recurrence were associated with reduced survival. Importantly, mGPS was the best at stratifying prognosis and could be used in conjunction with tumour grade to sub-stratify patient survival. CONCLUSION: This study demonstrated that prognosis of localized STS strongly correlates with mGPS, as an increasing score is associated with a poorer outcome. We note that 203 patients (41%) with an STS have evidence of systemic inflammation. We recommend the mGPS and other biochemical blood indicators be introduced into the routine diagnostic assessment in STS patients to stratify patient prognosis. Its use will support clinical decision-making, especially when morbid treatment options such as amputation are being considered. Cite this article: Bone Joint J 2022;104-B(1):168-176.

Surgical treatment and long-term outcomes of low-grade myofibroblastic sarcoma: a single-center case series of 15 patients.

BACKGROUND: Low-grade myofibroblastic sarcoma (LGMS) is a poorly studied, rare, soft tissue sarcoma. LGMS is characterized by a low malignancy potential, tendency for local recurrence, and low likelihood of distant metastases. However, no studies have reported on the surgical treatment method and its long-term outcomes. METHODS: We included all patients treated for LGMS at our institution between March 2010 and March 2021. Medical charts were retrospectively reviewed to collect demographic information, as well as information about the clinical course, tumor characteristics, and outcomes. Statistical analysis was performed to identify the factors associated with the recurrence rate. RESULTS: Fifteen patients who underwent surgical treatment were enrolled in this study. There were seven cases in the upper extremities, four in the trunk area, three in the lower extremities, and one in the head and neck area. There were no metastatic cases and two cases of local recurrence. CONCLUSIONS: The incidence of LGMS in the extremities or trunk may be higher than expected based on the current literature. Univariate analysis showed that local tissue invasion and surgical method could be associated with local recurrence. Although further large studies are needed to establish risk factors of local recurrence or extent of resection margins, based on our study, wide local excision under the proper diagnosis is the most important treatment.

Isolated Avulsion Fracture of the Lesser Trochanter in Adults.

BACKGROUND/AIM: Isolated fractures of the lesser trochanter (LT) of adults are rare and most of them are pathologic fractures due to an underlying malignancy. The aim of our study was to provide comprehensive information on the epidemiology, etiology, diagnostic approach, and treatment algorithm of adult LT fractures. PATIENTS AND METHODS: We present the cases of six patients who were treated for isolated LT fractures between November 2010 and May 2019. A literature review was performed to identify adult LT fracture cases in previous studies. RESULTS: In two patients, the LT fracture was the first manifestation of the underlying tumors. Through a literature review, we identified 32 adults with isolated LT fractures. Among these, 27 were pathologic fractures. In 11 pathologic fractures, LT avulsion was the first manifestation of malignancy. CONCLUSION: Metastasis and the first manifestation of an underlying malignancy should be suspected in adult patients with isolated LT fracture. A stepwise approach can prevent misdiagnosis and offer rational treatment modality.

Transepiphyseal resection for osteosarcoma in patients with open physes using MRI assessment.

AIMS: For paediatric and adolescent patients with growth potential, preservation of the physiological joint by transepiphyseal resection (TER) of the femur confers definite advantages over arthroplasty procedures. We hypothesized that the extent of the tumour and changes in its extent after neoadjuvant chemotherapy are essential factors in the selection of this procedure, and can be assessed with MRI. The oncological and functional outcomes of the procedure were reviewed to confirm its safety and efficacy. METHODS: We retrospectively reviewed 16 patients (seven male and nine female, mean age 12.2 years (7 to 16)) with osteosarcoma of the knee who had been treated by TER. We evaluated the MRI scans before and after neoadjuvant chemotherapy for all patients to assess the extent of the disease and the response to treatment. RESULTS: The mean follow-up period was 64.3 months (25 to 148) after surgery and no patients were lost to follow-up. On MRI evaluation, 13 tumours were near but not in contact with the physes and three tumours were partially in contact with the physes before neoadjuvant chemotherapy. Bone oedema in the epiphysis was observed in eight patients. After neoadjuvant chemotherapy, bone oedema in the epiphysis disappeared in all patients. In total, 11 tumours were not in contact and five tumours were in partial contact with the physes. The postoperative pathological margin was negative in all patients. At the last follow-up, 12 patients were continuously disease-free and three had no evidence of disease. One patient died due to the disease. Functionally, the patients with retained allograft or recycled autograft had a mean knee range of flexion of 126° (90° to 150°). The mean Musculoskeletal Tumor Society functional score was 27.6 (23 to 30). CONCLUSION: TER is an effective limb-salvage technique for treating malignant metaphyseal bone tumours in paediatric and young osteosarcoma patients with open physes when a good response to chemotherapy and no progression of the tumour to the epiphysis have been confirmed by MRI. Cite this article: Bone Joint J 2020;102-B(6):772-778.

Vision-based tracking system for augmented reality to localize recurrent laryngeal nerve during robotic thyroid surgery.

We adopted a vision-based tracking system for augmented reality (AR), and evaluated whether it helped surgeons to localize the recurrent laryngeal nerve (RLN) during robotic thyroid surgery. We constructed an AR image of the trachea, common carotid artery, and RLN using CT images. During surgery, an AR image of the trachea and common carotid artery were overlaid on the physical structures after they were exposed. The vision-based tracking system was activated so that the AR image of the RLN followed the camera movement. After identifying the RLN, the distance between the AR image of the RLN and the actual RLN was measured. Eleven RLNs (9 right, 4 left) were tested. The mean distance between the RLN AR image and the actual RLN was 1.9 ± 1.5 mm (range 0.5 to 3.7). RLN localization using AR and vision-based tracking system was successfully applied during robotic thyroidectomy. There were no cases of RLN palsy. This technique may allow surgeons to identify hidden anatomical structures during robotic surgery.

Factors Associated with Disease Stabilization of Desmoid-Type Fibromatosis.

BACKGROUND: Spontaneous disease stabilization of desmoid-type fibromatosis (DF) has been demonstrated in many reports, and the watchful waiting approach without any frontline treatment is becoming popular as an initial management strategy. In this study, we aimed to assess the disease stabilization rate and identify predictive factors for disease stabilization of DF in patients with conservative treatment. METHODS: We reviewed 76 patients with sporadic extra-abdominal DF who were managed with frontline conservative treatment in our institute. The minimum follow-up was 12 months. Stabilization was defined as radiological evidence of no change or continuous decrease in size of the tumor for six months or more. The primary endpoint was stabilization of DF. Possible patient-, disease-, and treatment-related factors predictive of disease stabilization were analyzed with multivariate analysis. RESULTS: At final follow-up, 54 of the 76 tumors (71%) were stable, and mean time to stabilization was 30.4 months (range, 7 to 112 months). On Kaplan-Meier survival analysis, the spontaneous stabilization rate was 25.4% at one year, 52.7% at two years, and 70.9% at three years. The mean time to spontaneous stabilization was longer in patients with ≤ 40 years of age (p = 0.022) or recurrence (p = 0.041). On multivariate analysis with the Cox proportional hazard method, recurrence (hazard ratio [HR], 1.79; p = 0.041) and younger age (HR, 2.04; p = 0.022) were identified as independent prognostic factors for longer time to disease stabilization. CONCLUSIONS: Frontline conservative treatment seems to be the optimal treatment for most patients with DF. Younger patients or those with recurrence may require longer time to spontaneous disease stabilization.

Ambulation Recovery After Surgery for Metastases to the Femur.

BACKGROUND: Postoperative ambulation recovery after surgery for femur metastases has significant implications for not only the patient's quality of life but also administration of further cancer treatment. Thus, identification of preoperative predictors of ambulation recovery is necessary to set appropriate expectations and guide treatment. This study aimed to assess ambulation recovery rate and identify predictors of ambulation recovery in patients undergoing surgery for femur metastases. MATERIALS AND METHODS: A total of 244 patients who underwent surgery for femur metastases at our institution were reviewed. Patients were considered ambulatory if they were able to walk independently or walk with aids and nonambulatory if they were wheelchair bound or bedridden. The following potential clinicopathologic factors that might predict postoperative ambulation recovery were evaluated: premorbid general status, cancer burden, and local factors. RESULTS: A total of 165 patients (68%) regained ambulatory status postoperatively. A multivariate analysis revealed poor Eastern Cooperative Oncology Group (ECOG) performance status (odds ratio [OR], 5.327; p < .001) and nonambulatory premorbid ambulatory status (OR, 7.459; p < .001) as independent predictors of poor ambulation recovery after surgery for femur metastases. Postoperative ambulatory status was significantly associated with postoperative survival time (p < .001). CONCLUSION: Postoperative ambulation recovery rate in our cohort was 68%. Premorbid ambulatory status and ECOG performance status are predictors of ambulation recovery in patients undergoing surgery for femur metastases. IMPLICATIONS FOR PRACTICE: Postoperative ambulation recovery rate in this cohort was 68%. Premorbid ambulatory status and Eastern Cooperative Oncology Group performance status are predictors of ambulation recovery in patients undergoing surgery for femur metastases.

Prognoses of superficial soft tissue sarcoma: The importance of fascia-tumor relationship on MRI.

BACKGROUND: Superficial soft tissue sarcoma (S-STS) has been reported to have more favorable prognoses than deep-seated STS. However, for some patients, poor prognoses have been observed and there is a need for better prognostication. The deep peripheral fascia lies in the border of the S-STS and can be consistently detected using magnetic resonance imaging (MRI). The relationship of the subcutaneous tumor with the fascia on MRI scan was reported to be useful in classifying the tumor as benign or malignant; this in turn, may reflect the biological aggressiveness of STS. This study was performed to evaluate the oncologic outcomes and to identify the prognostic factors of S-STS by focusing on the relationship of S-STS with the underlying fascia on MRI. MATERIAL AND METHODS: We retrospectively reviewed data on 253 patients who underwent resection of localized S-STS. Potential factors that might influence the oncologic outcomes were identified. The fascia-tumor relationship on MRI was classified into three groups: no fascial contact group (n = 46), fascial contact group (n = 77), and fascial invasion group (n = 84). RESULTS: Overall, 39 patients (16.5%) died due to S-STS; the 5- and 10-year survival rates were 82.6 ±â€¯2.9% and 73.2 ±â€¯4.5%, respectively. Fascial invasion detected on MRI scans (OR = 2.190, p = 0.034) and advanced age (OR = 2.408, p = 0.034) were found to be independent factors for worse disease specific survival. The fascia-tumor relationship on MRI scan was not associated with local recurrence of S-STS. CONCLUSION: The fascia-tumor relationship on MRI scan reflects the biological aggressiveness of S-STS and can serve as a prognostic factor.

Changing odds of survival over time among patients undergoing surgical resection of extremity soft tissue sarcoma.

BACKGROUND: While survival after surgical treatment of extremity soft tissue sarcoma (STS) is traditionally reported as actuarial survival, conditional survival (CS) may be more clinically relevant as it accounts for time already survived. We compared actuarial survival and CS of STS patients. MATERIALS AND METHODS: We analyzed 567 patients who underwent surgery for localized extremity STS. Actuarial survival was estimated using the Kaplan-Meier method. Cox proportional hazards model was used to evaluate factors associated with disease-specific survival. Five-year CS (CS5) estimates at "χ" year(s) after surgery were calculated as CS5 = S(χ + 5)/S(χ). RESULTS: Whereas actuarial survival decreased over time, CS5 increased. The postsurgical 1-, 3-, and 5-year CS5 values were 84.5%, 90.0%, and 93.8%, respectively, whereas the 6-, 8-, and 10-year actuarial survival rates were 82.0%, 79.4%, and 78.5%, respectively. The calculated CS5 exceeded actuarial survival especially in patients with risk factors such as large tumor size and Federation Nationale des Centers de Lutte Contre le Cancer (FNCLCC) grades 2 and 3 tumors. Patients with tumor size ≥5 cm had an actuarial survival of 73.9% at 10 years compared to a CS5 of 95.4% in patients alive at 5 years. Likewise, patients with FNCLCC grade 3 tumors had an actuarial survival of 71.1% at 10 years compared to a CS5 of 96.0% in patients alive at 5 years. CONCLUSIONS: Survival estimation by determination of CS can be dynamic and accurate especially in high-risk patients. CS can be useful for survival prediction and clinical decision making in extremity STS patients.

Comparison of the diagnostic performances of core needle biopsy in myxoid versus non-myxoid tumors.

BACKGROUND: Despite the overall diagnostic utility of core needle biopsy (CNB) comparable to incisional biopsy, increased diagnostic errors have been suggested of CNB for myxoid soft tissue tumors. This study compared the diagnostic performance of CNB between myxoid and non-myxoid soft tissue tumors. METHODS: 369 patients who underwent ultrasound-guided CNB prior to resection for soft tissue tumors were classified into two groups according to resection pathology; myxoid group (n = 75) and non-myxoid group (n = 294). One-hundred and ninety-three patients were male and the median age of the patients was 40 years. Two-hundred and sixty-three tumors were malignant. RESULTS: CNB correctly diagnosed malignancy in 84% (58 of 69) for the myxoid group and 95% (184 of 194) for the non-myxoid group. For diagnosing histologic grade of soft tissue sarcoma, CNB correctly identified high grade in 78% (18 of 23) for the myxoid group and 74% (94 of 128) for the non-myxoid group. Correct diagnosis rate of histological type was significantly lower in the myxoid group (63% [47 of 75] in the myxoid group and 83% [242 of 294] in the non-myxoid group, p = 0.013). CONCLUSION: Our study suggests that CNB is useful for myxoid soft tissue tumors of the extremity, with regard to diagnosing malignancy and histologic grade. However, CNB was less useful for identifying histologic subtype in myxoid tumors than in non-myxoid tumors.

Observational approach on regional lymph node in cutaneous melanomas of extremities.

PURPOSE: We evaluated failure pattern and treatment outcomes of observational approach on regional lymph node (LN) in cutaneous melanoma of extremities and sought to find clinico-pathologic factors related to LN metastases. MATERIAL AND METHODS: We retrospectively reviewed 73 patients with cutaneous melanoma of extremities between 2005 and 2016. If preoperative 18-F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) findings were non-specific for regional LNs, surgical resection of primary tumors with adequate margins was performed without sentinel lymph node biopsy (SLNB) and/or complete lymph node dissection (CLND), irrespective of tumor thickness or size. In patients with suspicious or positive findings on PET/CT or CT, SLNB followed by CLND or CLND was performed at the discretion of the surgeon. We defined LN dissection (LND) as SLNB and/or CLND. RESULTS: With a median follow-up of 38 months (range, 6 to 138 months), the dominant pattern of failure was regional failure (17 of total 23 events, 74%) in the observation group (n = 56). Pathologic LN metastases were significant factor for poor regional failure-free survival (hazard ration [HR] = 3.21; 95% confidence interval [CI], 1.03-10.33; p = 0.044) and overall survival (HR = 3.62; 95% CI, 1.02-12.94; p = 0.047) in multivariate analysis. In subgroup analysis for cN0 patients according to the preoperative PET/CT findings, LND group showed the better trend of LRFFS (log rank test, p = 0.192) and RFFS (p = 0.310), although which is not statistically significant. CONCLUSION: Observational approach on regional LNs on the basis of the PET/CT in patients with cutaneous melanoma of extremities showed the dominant regional failure pattern compared to upfront LND approach. To reveal regional lymph node status, SLND for cN0 patients may of importance in managing cutaneous melanoma patients.

Histological findings of regeneration in retrieved pasteurized bone grafts.

BACKGROUND: Despite a number of radiologic evaluations of the incorporation of pasteurized bone (PB) in human and histologic evaluations in animal models, there has been a scarce documentation regarding the histologic evaluation of PB from human. Herein, we present histologic findings of regeneration in retrieved PB graft from pediatric and adult patients. METHODS: PB was retrieved for various reasons in 7 patients (10-52 years old). Two bone pathologists independently counted the number of empty lacunae and lacunae with living cells in up to 10 randomly selected fields on medium-power (H&E, ×200) for each patient. Regeneration of PB was assessed as the ratio of the number of lacunae with nucleated cells to that of whole lacunae, which was defined as the "repair rate (RR)". RESULTS: The mean interval between initial reconstruction and retrieval (graft removal time; GRT) was 47.4 months (range, 11-144 months). The length of original PBs ranged from 5.8 to 20.6 cm. Microscopic examination of PBs showed areas with empty lacunae indicating necrosis and other areas contained lacunae with nucleated osteocytes, indicative of regeneration. Some Haversian canals of the PBs were filled with fibrovascular tissue and surrounded by lamellar bones including living osteocytes. RR varied widely from 21.7 to 62.4% with a mean of 36.8%. It was much higher in adult patients (46.6-62.4%, mean = 55.3%) than in pediatric patients (21.7-28.6%, mean = 25.3%), which was correlated with GRT (pediatric patients; mean of 14 months, adult patients; mean of 72.3 months). In adult patients, RR was higher in a patient with prosthesis composite in the proximal humerus (Case No. 3; 62.4%). CONCLUSIONS: RR was higher in whom GRT was longer, being correlated with GRT in retrieved PBs. In terms of our histological observation, PB is thought to be an acceptable temporary biologic spacer in limb-sparing surgery for malignant bone or soft tissue tumors.

EWSR1-PBX3 fused myoepithelioma arising in metatarsal bone: Case report and review of the literature.

Intraosseous myoepithelial tumors are very rare. Due to the low incidence and diverse histologic features, accurate diagnosis is challenging, necessitating ancillary immunohistochemistry. Moreover, genetic abnormality in this tumor was not revealed until recently. Although EWSR1 translocation is involved in half of the cases of intraosseous myoepithelioma, only a few cases have indicated its counterpart gene. We herein describe a case of intraosseous myoepithelioma with a novel localization in the fourth metatarsal bone of a 36-year-old female. Cytogenetic analysis using next generation sequencing detected a rare EWSR1-PBX3 fusion. Next generation sequencing could be useful in understanding the cytogenetic characteristics of intraosseous myoepithelioma, and in obtaining an accurate diagnosis of this rare condition.

MRI surveillance for local recurrence in extremity soft tissue sarcoma.

INTRODUCTION: The role of MRI in surveillance for local recurrence (LR) remains uncertain in extremity soft tissue sarcoma (STS). The aims of this study were 1) to examine the usefulness of MRI in detecting LR, 2) to identify the characteristics of LR detected by MRI, and 3) to examine whether MRI surveillance is associated with oncologic outcome. MATERIALS AND METHODS: 477 patients who had regular surveillance for LR after surgery for extremity STS were reviewed. Surveillance was performed by routine MRI in 325 patients or other imaging modalities in 152 patients. RESULTS: The rate of MRI-detected LR, defined as clinically undetectable LR identified on MRI, was 10.5% in the MRI surveillance cohort. The detection rates of MRI-detected LR were significantly higher in the patients with high risk of LR. MRI-detected LRs were more commonly located in the thigh or buttock (p = 0.005), were smaller (p = 0.001) and had LRs without mass formation (p = 0.007) than non-MRI-detected LRs. On Kaplan-Meier analysis, patients with MRI-detected LR tended to have better post-LR survival (p = 0.104). CONCLUSION: Routine MRI surveillance can detect a significant number of clinically undetectable LRs in extremity STS especially for LRs in the thigh or buttock, small LRs or LRs without mass formation.

Role of Nonsteroidal Anti-inflammatory Drug in Treatment of Extra-abdominal Desmoid Tumors.

BACKGROUND: We retrospectively reviewed the outcomes of patients who had been treated with meloxicam for the extra-abdominal desmoid tumors and evaluated the correlation between clinical outcome and clinic pathological variables. METHODS: Twenty patients treated with meloxicam were followed up every 3 to 6 months. Meloxicam administration was planned at 15 mg/day orally for 6 months. RESULTS: Of the 20 patients evaluated, according to Response Evaluation Criteria in Solid Tumors criteria, there were five patients with partial response (25.0%), eight with stable disease (40.0%), and seven with tumor progression (35.0%). The cumulative probability of dropping out from our nonsurgical strategy using meloxicam was 35.0% at 1 year and 35.0% at 5 years. CONCLUSIONS: The present study suggests that conservative treatment would be a primary treatment option for this perplexing disease even though we were not able to determine that the use of a cyclooxygenase-2 inhibitor would have an additional influence on the natural course of a desmoid tumor.

Optimal Treatment of Osteofibrous Dysplasia of the Tibia.

BACKGROUND: Our study of a large patient group reports on the behavior and postoperative recurrence of osteofibrous dysplasia (OFD). METHODS: We reviewed the medical records of 55 patients who were diagnosed with OFD of the tibia and showed typical features of this tumor. The patients' presentation, disease course, history of pathologic fracture, typical radiographic features, surgical treatment history, and surgical results were investigated. RESULTS: The longitudinal OFD lesion size peaks at a mean 13.3 years of age with a mean maximum proportionate size of 0.33. These lesions in 92% of the patients spontaneously presented with a stable disease course, while those in the other 8% continued increasing. There were no significant predictive factors of disease course. Among surgically treated lesions, we noted a higher rate of recurrence after curettage than after excision (P<0.001). Patients who underwent curettage and developed recurrence were significantly younger than those who did not (P=0.01). CONCLUSIONS: Our data suggest that observation can be the primary form of treatment for patients with OFD and that the disease would stop advancing with time. During observation, clinicians should carefully observe all patients with OFD because the relation between OFD and adamantinoma is unclear. If surgery is necessary due to severe morbidity, we recommend excision rather than curettage to prevent recurrence, especially for younger patients. LEVEL OF EVIDENCE: Level III.

Cortical Atrophy Related to Tumor Prosthesis in Skeletally Immature Osteosarcoma Patients.

BACKGROUND: Cortical atrophy is commonly observed after prosthetic reconstruction for bone sarcomas. However, relevant literature regarding this phenomenon in skeletally immature patients is limited. Therefore, in this study, we evaluated the incidence and patterns of cortical atrophy. We then assessed its predisposing factors. Finally, we analyzed whether cortical atrophy was associated with poor prosthesis survival. METHODS: We retrospectively reviewed 31 stems in 19 skeletally immature osteosarcoma patients who were treated with resection and tumor prosthesis surgery. We measured the cortical thickness using plain radiographs annually. The mean patient age was 11 years (range, 6 to 14 y) and the mean follow-up period was 10 years (range, 2 to 14 y). RESULTS: Cortical atrophy developed in 13 stems, all within 3 years. There were 3 gross types of cortical atrophy: hourglass in 5, sharpening in 4, and shortening atrophy in 4. On multivariate analysis, stem-cortex diameter ratio of ≥0.5 and age of less than 10 years were significantly associated with cortical atrophy (P=0.002 and P=0.019, respectively). Cortical atrophy was significantly associated with eventual prosthesis failure (9/13 in the cortical atrophy group vs. 4/18 in the nonatrophy group, P=0.035). CONCLUSIONS: Cortical atrophy is common in the skeletally immature patients with tumor prosthesis and is associated with prosthesis failure. Patients with cortical atrophy should be closely monitored for prosthesis failure and appropriately managed to prevent failures. LEVEL OF EVIDENCE: Level IV-therapeutic study.

Factors associated with local recurrence after surgery for bone metastasis to the extremities.

BACKGROUND AND OBJECTIVES: With increasing life expectancy of patients with bone metastasis, durable surgical stabilization of bone metastasis is necessary. Local recurrence (LR) can compromise surgical stabilization and necessitate retreatment. We analyzed LR rate and factors associated with LR in patients undergoing surgery for bone metastasis. METHODS: Patients (n = 301) who underwent surgery for bone metastasis to the extremities were reviewed. Possible factors that might be associated with LR were investigated. RESULTS: LR rate was 16% (49/301). Surgical margin was associated with LR, as patients with en-bloc resection had significantly less LR than patients who underwent curettage (5/66 vs 44/235, P = 0.03). Prostate cancer had lowest rate (0%) of LR and colon cancer had highest rate (31%). Interval from surgery to LR differed among primary cancer types (4.5 ± 3.9 months [lung cancer], vs 12.3 ± 12.9 months [other cancers], P = 0.041). In multivariate analysis, en-bloc surgical margins (HR = 0.372, P = 0.036) and primary cancers of breast or prostate (HR = 0.391, P = 0.049) were independent factors associated with longer LR-free survival. CONCLUSIONS: LR after surgery for bone metastasis to extremities is affected by surgical margin and primary cancer type. These factors, along with expected patient survival, need to be considered when planning surgery for bone metastasis to extremities.