Low-grade Malignant Bone Tumors Research Articles

Analysis of demographic and socioeconomic factors in adamantinoma using data from the National Cancer Database (NCDB).

e23501 Background: Adamantinoma is a rare low-grade primary malignant bone tumor accounting for less than 1% of all malignant bone tumors. It largely presents in the tibia of young adults, is locally aggressive, and can metastasize. Definitive diagnosis is primarily established by histopathological examination. This rare tumor with uncertain histogenesis remains under-studied. Therefore, exploring trends in diagnoses may provide insight into its epidemiology. The National Cancer Database (NCDB) was examined to reveal the demographic factors in patients diagnosed with Adamantinoma. Methods: A retrospective cohort analysis utilizing the 2004–2020 NCDB included 206 patients with a histologically-confirmed diagnosis of adamantinoma (ICD-O-3 Code 9261). Demographic factors such as age, sex, race, Hispanic status, insurance status, facility type, distance from facility, and Charlson-Deyo score were analyzed via descriptive statistics. Trends in incidence were interpreted using regression analysis. Results: A total of 206 patients were identified in the NCDB with a confirmed diagnosis of adamantinoma of long bones between 2004-2020. Incidence remained relatively stable over this time period (R² = 0.009). The most common primary site of diagnosis were the long bones of lower limb and associative joints (97%). Most individuals (88%) had a Charlson-Deyo comorbidity score of 0. The majority of patients (66%) were classified as Stage 1 AJCC staging. Men were more likely to be diagnosed (56%) compared to women (44%). Most patients were White (78%) and non-Hispanic (85%). A higher percentage of patients were privately insured (67%) and lived in metropolitan areas (87%). Treatment facilities primarily were academic programs (74%). Almost all of the patients were treated surgically (92%) with the most common approach being lymph node dissection (61%) more so than local tumor excision or removal of adjacent organs. Following surgery, the patients observed had a very good prognosis, with a 99% ninety-day survival, a 93% five-year survival, and an 89% ten-year survival. Conclusions: Adamantinoma has a risk for recurrent and metastatic disease. This first NCDB analysis on adamantinoma’s demographics addresses a significant knowledge gap on this topic. The primary site of diagnosis were lower extremity long bones, most commonly treated with surgical intervention, and had a high survival rate which is consistent with earlier studies. The majority of patients included in this study tend to be White, non-Hispanic, and privately insured. This may suggest a demographic and socioeconomic factor that plays a part in diagnosis, prognosis, and treatment of individuals with adamantinoma. Future research should focus on the understanding of factors that impact the course of one’s health and the etiology of this rare pathology.

Bone Substitutes in Management of Benign Bone Tumors, Review of Literature

Intralesional excision or curettage is commonly used to treat benign and low-grade malignant bone tumors. The resulting defect can be treated with a variety of materials, such as autologous bone grafts, allografts, or synthetic materials like polymethylmethacrylate or composite alternatives. Because it is osteogenic, osteoinductive, and osteoconductive, autologous cancellous bone is often considered the gold standard of transplant material. However, issues including transplant size limitations, wound-related complications, and prolonged donor site pain have limited its usage in clinical practice. Concerns about immunogenicity and infection have also hampered the use of demineralized freeze-dried allografts and xenografts. As a result, synthetic materials have sparked substantial interest in orthopedics, and a variety of bone graft alternatives are now commercially accessible.

Artificial Bone Graft Substitutes for Curettage of Benign and Low-Grade Malignant Bone Tumors: Clinical and Radiological Experience with Cerasorb

BackgroundArtificial bone graft substitutes (ABGS) for curettage of bone tumors are becoming increasingly popular. The aim of this retrospective analysis was to determine the efficacy of the ABGS Cerasorb (Curasan-AG, Kleinostheim, Germany), a beta-tricalcium phosphate (beta-TCP), concerning resorption profile, bone healing, and remodeling after surgery and to evaluate potential complications.MethodsForty-three patients suffering from benign and low-grade malignant bone tumors were treated with curettage and refilling of the bony cavity using the ABGS Cerasorb between 2018 and 2021 and included in the final analysis. Clinical follow-up exams with X-rays in two planes were performed 6 weeks, 3 months, 6 months, and 1 year after surgery.ResultsAfter a mean follow-up period of 14.6 months, radiological consolidation following curettage was observed in all patients. Total resorption was observed in 16.3% of patients; in the other 83.7%, resorption was partial. In four patients, of whom two had a tumor in the distal femur and two in the humeral diaphysis, fractures occurred within 6 weeks after primary surgery.ConclusionIn conclusion, the beta-TCP Cerasorb seems to be a reliable bone graft substitute with low complication rates and is a suitable alternative to autologous bone grafts or allografts. Nonetheless, it shows a tendency of delayed resorption.Level of EvidenceIII; retrospective cohort study.

Injectable Synthetic Beta-Tricalcium Phosphate/Calcium Sulfate (GeneX) for the Management of Contained Defects Following Curettage of Benign Bone Tumours.

Benign and low-grade malignant bone tumours are often treated with curettage and filling of the resultant defect using any of a number of materials, including autologous bone grafts, allografts, or synthetic materials. The objective of this study was to report our experience using a synthetic bone graft substitute in these patients. Ten consecutive cases (four males, six females; mean age, 36 years) of benign bone tumours were treated surgically at a tertiary musculoskeletal oncology centre, between 2019 and 2021. Following curettage, the contained defects were managed with injectable beta-tricalcium phosphate/calcium sulfate (GeneX; Biocomposites Ltd., Keele, UK). The desired outcomes were early restoration of function and radiographic evidence of healing. No other graft materials were used in any of the patients. The mean follow-up was 24 months (range, 20-30 months). All patients in this series (100%) demonstrated radiographic evidence of healing and resumed their daily living activities. There were no tumour recurrences and no complications were encountered with the use of GeneX. In patients with contained defects following curettage of benign bone tumours, we found GeneX to be a safe and effective filling agent. These findings contrast with some existing studies that have reported local complications with the use of injectable beta-tricalcium phosphate/calcium sulfate.

Adamantinoma of Tibia: A Case Report and Literature Review

Adamantinoma of long bones is a slow-growing, low-grade primary malignant bone tumor. It is a rare entity and accounts for less than 1% of all primary bone tumors, and in most cases, it occurs in the mid-axis of the tibia of adolescents and young adults. In this report, we describe the case of a 55-year-old woman with a diagnosis of adamantinoma of the left tibia.

Utility of 45S5 Bioactive Glass As Bone Graft Substitute for Cavitary Defects in Pediatric Bone Tumors: A Preliminary Study.

Bioactive glass has become an increasingly used treatment of cavitary bone defects in a number of orthopaedic applications. The purpose of this study was to evaluate the clinical and radiographic outcomes of bioactive glass used for benign cavitary pediatric bone tumors. A specific focus was on radiographic filling of defects and occurrence of complications by tumor class. A single institution retrospective study was performed, which entailed review of the clinical and radiographic data of 21 patients who underwent surgical curettage and grafting of benign or low-grade malignant bone tumors from 2018 to 2020. In all the cases, 45S5 bioactive glass (Fibergraft; Prosidyan, New Providence, NJ) was used to fill the bone defects. For each patient, data on demographic, preoperative diagnosis, defect size, time to mobilization, radiographic filling grade, pain, and complications were obtained. The Wilcoxon-Mann-Whitney test and Kaplan-Meier survival analysis were used for comparisons between tumor classes. In the 21 patients, 11 bone tumors were latent or active (class 1) and 10 were aggressive (class 2). The mean age was 13.0±3.7 years, 6 (28.6%) were female, and the median and interquartile range for initial tumor size were 18.8 (5.8 to 50.6) cm 3 . Tumors that were class 2 had significantly more complications with bioactive glass use compared with class 1 tumors [0 vs. 1 (0 to 1), P =0.040]. The time of persistent fill grade 1 or 2 defects up to final follow-up was less in class 1 versus class 2 lesions ( P =0.048). Bioactive glass agents have utility for treating a broad variety of pediatric bone tumors after curettage. However, focusing these agents' use in treating latent or active subtypes of bone tumors may be ideal in minimizing complications and time to higher fill grade. Level III - Therapeutic.

Review of Adamantinoma Tumor Characteristics and Treatments in the National Cancer Database (NCDB/NCD)

Background: Adamantinomas are rare low-grade malignant bone tumors of uncertain origin, which manifest primarily in the anterior mid-tibial shaft. Growth is indolent with significant risk of delayed-onset recurrence and/or distant metastasis. The aim of this study is to describe the physical characteristics and treatments of adamantinomas in patients diagnosed through the NCDB. Methods: This is a retrospective study of all patients diagnosed with adamantinomas between 2004 and 2017 in the National Cancer Database. Adamantinomas were identified using ICD-O-3 code 9261. Description statistics and univariate Kaplan-Meier curves were performed using SPSS. No patients were excluded from analysis. Results: 97% of adamantinoma lesions were in the long bones of the lower extremities. Incidence was similar bilaterally, behavior was universally invasive, grade was 66.1% undetermined, stage was 63.7% stage 1, and mean diameter was 63.67 ± 42.8 mm. Only 2 instances of metastasis (bone) at diagnosis were recorded. Treatment was overwhelmingly surgery with an open approach radical excision or resection of the primary lesion with limb salvage and clean surgical margins regardless of tumor grade, stage, primary site, or size. 5, 10, and overall survival were 96.8%, 94.2%, and 92.9% respectively. Conclusion: Adamantinomas are rare slow-growing malignant tumors that primarily affect the anterior cortex of the tibia and have significant potential for recurrence and metastasis, thus should be treated with radical surgical resection and excision to obtain clear margins. Overall prognosis is favorable, but patients should be enrolled in a long-term surveillance program to periodically rule-out recurrence or metastasis.

Epidemiological Study of Adamantinoma from US Surveillance, Epidemiology, and End Results Program: III Retrospective Analysis.

Objective Adamantinomas are rare low-grade malignant bone tumors. This study aims to describe the demographic characteristics and survival rates of patients suffering from adamantinomas. Methods The National Institute of Cancer Surveillance, Epidemiology, and Recent Results (SEER) database was used, and patients diagnosed with adamantinoma between 1973 and 2016 were screened. Patients were classified according to sex, age, race/ethnicity, and marital status, and also tumors were classified according to year of diagnosis, laterality, type of treatment, and follow-up. Results The mean age of patients was 30.8 ± 16.7 (range: 4–75). A total of 92 patients were identified; of these, 43 were females and 49 were males. The mean follow-up period was 138.1 ± 90.3 (range: 1–156) months. Mean survival duration was 287.8 ± 15.4 (95% CI: 257.7–317.9) months. Five- and ten-year survival rates were 98.8% and 91.5%, respectively. Besides, survival time was also observed to be independent of gender, age groups, race, marital status, tumor location, and year of diagnosis. Conclusion Adamantinoma is a very rare bone tumor that affects the long bones in lower extremities and is more common in men. Five- and 10-year survival prognoses are reasonably satisfactory. Also, survival time is independent of variables such as gender, age, and tumor location.

Adamantinoma of the Femur With High-Grade Epithelial and Sarcomatoid Components: Case Report and Review of the Literature

Abstract Adamantinomas are rare low-grade malignant bone tumors that are composed of epithelial cells set in an osteofibrous stroma. Osteofibrous dysplasia-like and classic forms are well known; however, sarcomatous transformation (dedifferentiation) is very rarely observed. We present the case of a 48-year-old woman who presented with a 5-cm proximal femoral lytic lesion at risk of pathologic fracture. Frozen-section evaluation demonstrated an intimate admixture of atypical squamous nests and spindle cells, consistent with metastatic sarcomatoid carcinoma, so prophylactic intramedullary nailing was completed. Postoperative clinical and radiologic evaluation failed to identify a primary carcinoma, and short-term follow-up demonstrated rapid tumor spread throughout the femur and thigh. The patient underwent hip disarticulation, and microscopic examination demonstrated areas of classic adamantinoma associated with both high-grade epithelial and sarcomatoid components. Diffuse metastatic spread was evident within seven months. Along with a description of this case, we review the clinical, radiographic, histologic, and immunophenotypic characteristics of the eight adamantinomas with high-grade sarcomatous transformation that have been previously reported in detail in the English literature, and discuss important considerations for differential diagnosis.

Limb salvage surgery with joint preservation for malignant humeral bone tumors: operative procedures and clinical application

BackgroundHowever, the application of limb salvage with joint preservation is controversial. The purpose of this study is to propose a selection strategy of joint-sparing operative procedures for humeral malignancies based on tumor origin, site and bone strength.MethodsThe medical data of 28 patients with humeral malignancies treated at our institute from January 2010 to December 2016 were analyzed retrospectively. The patients had a median age of 51 years (range, 8–82 years). Bone strength scoring system was utilized to evaluated bone strength of the tumor. Four joint-sparing surgical methods were performed on selected patients. Evaluation of limb function was based on the Musculoskeletal Tumor Society scoring system. Two-sample t-test was used to compare patient group data such as bone strength score and postoperative Musculoskeletal Tumor Society score.ResultsThe mean follow-up period for the 7 patients with primary malignancies was 45 months (range, 15–66 months). One patient died due to recurrence and lung metastasis, while the remaining 6 patients (6/7, 85.7%) survived without recurrence. For the 21 patients with metastases, 5 survived with tumors, with an average survival time of 25.8 months (range, 9–48 months). The rest died from progression of the primary tumors. The mean bone strength score for the biological reconstruction group and non-biological reconstruction group was respectively 9.7 ± 1.3 and 12.9 ± 1.2. A significant difference between the 2 groups (p < 0.05) was found. Mean postoperative Musculoskeletal Tumor Society score was respectively 27.2 ± 1.8 and 26.1 ± 1.7 for the 2 groups. There was no significant difference between the 2 groups (p > 0.05). Non-oncological complications included fracture (1), aseptic loosening (1) and radial nerve injury (1).ConclusionsAlcohol devitalized autograft replantation is applicable for diaphyseal humeral primary malignancies, with a good response to chemotherapy and a low bone strength score (≤10). In situ microwave ablation is suitable for diaphyseal and (or) metaphyseal low-grade malignant bone tumors or metastases with a low bone strength score (≤10). Intercalary prosthetic reconstruction is preferred for diaphyseal metastases with a high bone strength score (> 10).

Parosteal osteosarcoma: a monocentric retrospective analysis of 195 patients

Parosteal osteosarcoma is a low-grade malignant bone tumor that can undergo dedifferentiation. The aim of this study was to analyze clinicopathologic features associated with clinical outcome in a large cohort of patients. Patients consecutively treated for parosteal osteosarcoma at Rizzoli Orthopedic Institute from 1900 to 2018 were reviewed and analyzed. Clincopathologic data of 195 patients with parosteal osteosarcoma were analyzed. Age at diagnosis ranged from 9 to 75 years (median 31). Median follow-up time was 150 months (range, 3-720). The most common tumor locations were femur (61.5%), humerus (15.9%) and tibia (12.8%). Wide surgical margins were achieved in 125 (64.1%) patients. Medullary involvement was present in 69 (35.4%) cases. Dedifferentiation occurred in 48 (24.6%) patients. Forty-five patients developed recurrence (23.1%; median time to recurrence of 36 months). At last follow-up, 155 (79.5%) patients were alive and without evidence of disease, 8 (4.1%) were alive with active disease, 23 (11.8%) died from disease, and 9 (4.6%) from unrelated causes. Patients with dedifferentiated parosteal osteosarcoma had worse 5-year (65% versus 96%) and 10-year survival (60% versus 96%) when compared to conventional tumors (P < .001). Wide surgical margins had positive impact on both disease-free (P < .001) and overall survival (P = .036). Medullary involvement, age at presentation and tumor size had no impact on survival. Dedifferentiation is the most important factor that negatively impacts clinical outcome. Surgical aim is to ensure radical removal with wide surgical margins to improve disease-free survival.

Intradural cervical chordoma with diffuse spinal leptomeningeal spread: case report and review of the literature

Chordoma is a low-grade malignant bone tumor derived from embryonic notochord remnants along the axial skeleton. About 50% of chordomas occur in the sacral vertebrae and 35% in the skull base. Most chordomas are extradural and cause extensive bone destruction. Intradural spinal tumors without bone involvement are rare. We herein describe the clinical features of a patient with a chordoma as well as the imaging and pathological manifestations of the tumor. We encountered an unusual presentation of a C6 and C7 spinal intradural chordoma in a 23-year-old man. He presented with a 5-day history of discomfort over the lumbosacral region. Magnetic resonance imaging and enhanced scanning of the cervical spine showed an intradural soft tissue mass at C6 and C7 and linear enhancement of the spinal meninges. The tumor was excised because the patient had been previously misdiagnosed with an intraspinal neurogenic tumor with spinal meningitis. Postoperative pathological examination confirmed the diagnosis of chordoma. On postoperative day 7, the patient underwent brain magnetic resonance imaging because of severe headache. The images showed multiple soft tissue nodules in the skull base cistern. To the best of our knowledge, this is the first case report of an entirely extraosseous and spinal intradural chordoma with diffuse spinal leptomeningeal spread. The patient died 2months postoperatively. An intradural spinal chordoma is difficult to distinguish from a neurogenic tumor by imaging. When the lesion is dumbbell-shaped, it is easily misdiagnosed as a schwannoma. In the present case, the tumor was intradural and located at the level of the C6 and C7 vertebrae. Preoperative diagnosis was difficult, and the final diagnosis required pathological examination.

Treatment of low-grade malignant bone tumor of limb by half-side cortical resection and inactivated replantation

Objective To study the curative effect of side bone cortex resection and inactivated replantation in the treatment of low limb malignant bone tumor. Methods 58 patients who diagnosed and treated for low limb malignant bone tumor were selected as the research subjects, and they were randomly divided into observation group and control group, each group in 29 cases.The artificial joint replacement was used in patients with the ordinary routine therapy, the observation group received side a thorough treatment of the wounded inactivated bone cortex excision.The clinical curative effect, operation indicators, and postoperative infection were compared and analyzed in the two groups. Results The total effective rate of the observation group was 96.55% (17 cases had marked effect, effective in 11 cases, failure in 1 case). The total effective rate of the control group was 72.41% (9 cases had marked effect, effective in 12 cases, failure in 8 cases), the clinical curative effect of the observation group was significantly higher than the control group (χ2=6.44, P<0.05). In addition, the anxiety and the operation indicators between the two groups had statistically significant differences (t1=5.47, t2=5.47, all P<0.05, the former is superior to the latter). Conclusion Side bone cortex inactivated replantation in the treatment of low-grade malignant bone tumor resection patients can effectively shorten the operation time and reduce the intraoperative blood loss, bad mood, and also can alleviate patients to obtain ideal therapeutic effect, clinical should be vigorously promoted. Key words: The wounded side of cortical bone resection inactivated; Bone neoplasms; The curative effect

Clinical experience with the artificial bone graft substitute Calcibon used following curettage of benign and low-grade malignant bone tumors

Artificial bone graft substitutes, such as Calcibon, are becoming increasingly interesting as they do not cause donor site morbidity which is an advantage compared to autologous bone grafts. The aim of this study was to evaluate the efficacy and potential complications associated with the use of Calcibon. Twenty-seven patients with benign and low-grade malignant bone tumors were treated with curettage and refilling of the bony cavity. Based on the radiological classification system of Neer, these lesions only comprised Grade I lesions, describing cysts that only require curettage and filling, but no additional treatment. At a mean follow up of six months we observed radiological consolidation without resorption of the bone graft substitute. These observations were also made at a mean follow-up of 13 and 32 months, respectively. According to the classification system of Goslings and Gouma we observed six surgical complications. Summing up, Calcibon seems to be a reliable bone graft substitute with low complication rates. However, delayed resorption should be expected. Calcibon seems to be an alternative to autologous bone grafts or allografts in adequate indications.

Traitement de l’adamantinome et de la dysphasie fibreuse des os longs. Résultats à long terme

IntroductionAdamantinoma (AD) is an ultimately rare, low-grade malignant bone tumor. In most cases, it occurs in the tibia of young adults. Osteofibrous dysplasia (OFD) is a rare, benign, lesion that is typically seen in children. Histopathology, ultrastructure and cytogenetics indicate that these lesions are closely related. Yet, etiology remains a matter of debate. Local recurrence rates are high for both entities as published in literature and long-term outcomes are scarce, due to the rarity of the disease. HypothesisAD should be treated by “en bloc” resection while ODF can be treated by curettage or by observation. Consequently, the aim of the present study was to answer following questions: were local recurrence rates of both entities different based on a retrospective review within a tertiary referral center for orthopedic oncology? Material and methodsIn a retrospective cohort study, 10 patients with AD and 5 patients with OFD (including 1 patient with OFD-like-AD) were reviewed. Primary surgeries for patients with AD were: “en bloc” resection in 7, curettage in 2 and amputation in 1. In the OFD groups, only 2 patients underwent surgery by curettage. Mean follow-up was 16 years (range: 2–47 years). Nine patients had a minimum follow-up of 10 years (mean: 23 years; range: 10–47 years). ResultsFour patients with AD (40 %) and 2 patients with OFD (40 %) - all of them following surgical removal - suffered from local recurrence. In the “en bloc” resection group of AD, there were 2 LR (29 %). All patients of both groups treated with curettage showed LR. One patient with AD had metastasis at time of diagnosis and died of disease. Another patient with AD was diagnosed with metastasis 67 months after surgery and was still alive with disease at latest follow-up (77 months). DiscussionThe overall prognosis of AD and OFD is good, yet local recurrence rates are high, irrespective of surgical strategy. While an internationally standardized treatment regime is still missing, a more radical surgical approach should be considered, especially when treating AD. Type of study and level of proofRetrospective study; level IV.

Long-term outcome following treatment of Adamantinoma and Osteofibrous dysplasia of long bones

IntroductionAdamantinoma (AD) is an ultimately rare, low-grade malignant bone tumor. In most cases it occurs in the tibia of young adults. Osteofibrous dysplasia (OFD) is a rare, benign, lesion that is typically seen in children. Histopathology, ultrastructure, and cytogenetics indicate that these lesions are closely related. Yet, etiology remains a matter of debate. Local recurrence rates are high for both entities as published in literature and long-term outcomes are scarce, due to the rarity of the disease. HypothesisAD should be treated by En-Bloc resection while ODF can be treated by curettage or by observation. Consequently, the aim of the present study was to answer following questions: Were local recurrence rates of both entities different based on a retrospective review within a tertiary referral center for orthopedic oncology? Material and methodsIn a retrospective cohort study, 10 patients with AD and 5 patients with OFD (including 1 patient with OFD-like-AD) were reviewed. Primary surgeries for patients with AD were: En-bloc resection in 7, curettage in 2 and amputation in 1. In the OFD group, only 2 patients underwent surgery by curettage. Mean follow-up was 16 years (range: 2–47 years). Nine patients had a minimum follow-up of 10 years (mean: 23 years; range: 10–47 years). ResultsFour patients with AD (40%) and 2 patients with OFD (40%) – all of them following surgical removal – suffered from local recurrence. In the “En bloc” resection group of AD, there were 2 LR (29%). All patients of both groups treated with curettage showed LR. One patient with AD had metastasis at time of diagnosis and died of disease. Another patient with AD was diagnosed with metastasis 67 months after surgery and was still alive with disease at latest follow-up (77 month). DiscussionThe overall prognosis of AD and OFD is good, yet local recurrence rates are high, irrespective of surgical strategy. While an internationally standardized treatment regime is still missing, a more radical surgical approach should be considered, especially when treating AD. Level of evidenceRetrospective study; Level IV.

Indications for prophylactic osteosynthesis associated with curettage in benign and low-grade malignant primitive bone tumors of the distal femur in adult patients: a case series.

BackgroundThe aim of the study was to evaluate whether the use of preventive osteosynthesis after curettage in benign and primitive low-grade malignant bone tumor localized in the distal femur in adult patients provides sufficient mechanical stability to the system as to allow weight-bearing and reduce the risk of postoperative fracture. Additionally, lower limb function after curettage and preventive osteosynthesis was evaluated.Materials and methodsWe analyzed twelve cases of benign and low-grade malignant bone lesions of the distal femur in adult patients treated in our orthopedic department between 2008 and 2011 with curettage, bone filling and preventive osteosynthesis. All patients were treated with curettage with the use of high-speed cutters, plus liquid nitrogen as local adjuvant in low-grade malignant lesions, and filling of the lesion with bone graft or allograft or acrylic cement, followed by osteosynthesis.ResultsNo fractures or major complications were observed; good function of the knee was observed.ConclusionWe recommend preventive osteosynthesis after curettage in patients with very large lesions (>5 cm, >60 cm3) or high functional requirements, in obese patients, and when local adjuvants are used.Level of evidenceLevel IV retrospective case-series study.

Evaluation of Clinical Results and Complications of Structural Allograft Reconstruction after Bone Tumor Surgery.

Massive bone allograft is an option in cases of limb preservation and reconstruction after massive benign and malignant bone tumor resection. The purpose of this study was to analyze the outcome of these procedures at Imam Reza Hospital, Mashhad University of Medical Sciences. In this study, 113 cases have been presented. Eleven cases were excluded (patients has a traumatic defect or they passed away before the completion of the study's two-year follow up period). Each patient completed a questionnaire, went through a physical examination and, if indicated, X-ray information was collected. The patients were divided into three groups: chemotherapy, chemotherapy plus radiation therapy, and no-adjuvant-therapy. Fifty-four cases were male and the mean age was 24.5±5.39. The number of cases and indications for surgery were: 33 cases of aggressive benign tumors or low grade malignant bone tumors (large bone defects) including 16 germ cell tumors, eight aneurysmal bone cysts, five low grade osteosarcomas, and four chondrosarcomas. Another 69 cases were high-grade malignant bone tumors including 42 osteosarcomas, 21 Ewing's sarcoma, and six other high grade osteosarcomas. Patients were divided into three groups: the first group received no adjuvant therapy, the second group received chemotherapy, and the third group received chemotherapy plus radiotherapy. The location of tumors were as follows: eight cases in the pelvic bone, 12 in the proximal femur, 18 in the femoral shaft, 36 in the distal femur, 12 in the proximal tibia, and 16 in the humeral bone. The 12 cases of proximal femoral defects were reconstructed by allograft composite prosthesis, 18 diaphyseal defects with intercalary allograft, and 36 distal femoral defects were reconstructed using osteoarticular allograft. The rate of deep infection was 7:8% (eight patients) and in this regard, we found a significant difference among the three groups, such that most cases of infection occurred in the adjuvant chemotherapy plus radiation therapy group. Allograft fracture occurred in six patients and prevalence was the same in all groups. Only in six cases of radio-chemotherapy nonunion occurred, so we used autogenous bone graft for union. Local recurrence was observed in six patients: three belonged to the adjuvant chemotherapy group and the other three were in the chemo-radiotherapy group; no significant difference was observed between these two groups. However, there was a significant difference between these two and the group that received no adjuvant therapy. Also, there were 11 cases of metastases and Restriction of knee joint motion occurred in 48 cases of osteo-cartilaginous grafts of the distal femur and proximal tibia. Although structural allograft is an appropriate choice in limb reconstruction after massive resection of involved tissues in malignant and invasive bone tumors, the risk of complications such as nonunion and infection in massive allograft increases in cases of adjuvant (chemotherapy and radiotherapy) modalities of treatment. Whereas the rate of tumor recurrence, metastasis, and restrictions in range of motion during a short term follow up after implantation showed no significant difference among the evaluated groups. Consequently, further attention and constant periodic visits of the patients and checking for local recurrence and distant metastasis should be done after surgery.

Research progress of biological behavior of spinal chordoma in motion segment

Chordomas are low-grade malignant bone tumors that arise from remnants of notochord or aberrant chordal tissue, and have a predilection for the axial skeleton. They are easily recurrent, locally invasive, and have a poor prognosis. Chordomas are also not sensitive to chemotherapy or radiotherapy. Due to the special anatomy of spine, chordomas of mobile spine have their own characteristics. Therefore, this paper reviewed relevant literatures of recent 10 years and summarized the characteristics of biological behavior of mobile spine chordoma, so as to provide new ideas for treating chordoma. DOI: 10.3969/j.issn.1672-6731.2016.04.004

A Case of Metastatic Adamantinoma That Responded Well to Sunitinib.

Adamantinoma is a rare low-grade malignant bone tumor of epithelial origin. Metastatic adamantinoma has been reported to be resistant to chemotherapy. We report a case of metastatic adamantinoma to the lung, 10 years after the initial diagnosis of tibial mass. The patient received radiation therapy to the lung with partial response. A surveillance PET scan revealed progression of the lung mass and biopsy confirmed to be progressive residual metastatic adamantinoma. He received carboplatin and etoposide for 7 months and achieved a partial response. Four months later, PET scan showed disease progression. We started him on sunitinib, a multikinase inhibitor. He achieved a good partial response for 3 years. He died due to pneumonia at the age of 72.