Sarcomas arising in Paget disease of bone: a clinicopathologic analysis of 70 cases

Osteosarcoma in Pediatric and Adult Populations: Are Adults Just Big Kids?

Malignant bone tumors are commonly classified as pediatric or adolescent malignancies, and clinical trials for these diseases have generally focused on these populations. Of primary bone cancers, osteosarcoma is among the most common. Osteosarcoma has a bimodal age distribution, with the first peak occurring in patients from 10 to 14 years old, and the second peak occurring in patients older than 65, with about 25% of cases occurring in adults between 20 and 59 years old. Notably, adult osteosarcoma patients have worse outcomes than their pediatric counterparts. It remains unclear whether age itself is a poor prognostic factor, or if inherent differences in tumor biology exist between age groups. Despite these unknowns, current treatment strategies for adults are largely extrapolated from pediatric studies since the majority of clinical trials for osteosarcoma treatments are based on younger patient populations. In light of the different prognoses observed in pediatric and adult osteosarcoma, we summarize the current understanding of the molecular etiology of osteosarcoma and how it may differ between age groups, hypothesizing why adult patients have worse outcomes compared to children.

GP, Kumar SU, El Allali A, Alsamman AM, Zayed H. Integrated gene network analysis sheds light on understanding the progression of Osteosarcoma

Introduction

Osteosarcoma is a rare disorder among cancer, but the most frequently occurring among sarcomas in children and adolescents. It has been reported to possess the relapsing capability as well as accompanying collateral adverse effects which hinder the development process of an effective treatment plan. Using networks of omics data to identify cancer biomarkers could revolutionize the field in understanding the cancer. Cancer biomarkers and the molecular mechanisms behind it can both be understood by studying the biological networks underpinning the etiology of the disease.

Methods

In our study, we aimed to highlight the hub genes involved in gene-gene interaction network to understand their interaction and how they affect the various biological processes and signaling pathways involved in Osteosarcoma. Gene interaction network provides a comprehensive overview of functional gene analysis by providing insight into how genes cooperatively interact to elicit a response. Because gene interaction networks serve as a nexus to many biological problems, their employment of it to identify the hub genes that can serve as potential biomarkers remain widely unexplored. A dynamic framework provides a clear understanding of biological complexity and a pathway from the gene level to interaction networks.

Results

Our study revealed various hub genes viz. TP53, CCND1, CDK4, STAT3, and VEGFA by analyzing various topological parameters of the network, such as highest number of interactions, average shortest path length, high cluster density, etc. Their involvement in key signaling pathways, such as the FOXM1 transcription factor network, FAK-mediated signaling events, and the ATM pathway, makes them significant candidates for studying the disease. The study also highlighted significant enrichment in GO terms (Biological Processes, Molecular Function, and Cellular Processes), such as cell cycle signal transduction, cell communication, kinase binding, transcription factor activity, nucleoplasm, PML body, nuclear body, etc.

Conclusion

To develop better therapeutics, a specific approach toward the disease targeting the hub genes involved in various signaling pathways must have opted to unravel the complexity of the disease. Our study has highlighted the candidate hub genes viz. TP53, CCND1 CDK4, STAT3, VEGFA. Their involvement in the major signaling pathways of Osteosarcoma makes them potential candidates to be targeted for drug development. The highly enriched signaling pathways include FOXM1 transcription pathway, ATM signal-ling pathway, FAK mediated signaling events, Arf6 signaling events, mTOR signaling pathway, and Integrin family cell surface interactions. Targeting the hub genes and their associated functional partners which we have reported in our studies may be efficacious in developing novel therapeutic targets.

A mutation in the ZNF687 gene that is responsible for the severe form of Paget's disease of bone causes severely altered bone remodeling and promotes hepatocellular carcinoma onset in a knock-in mouse model

Paget's disease (PDB) is a late-onset bone remodeling disorder with a broad spectrum of symptoms and complications. One of the most aggressive forms is caused by the P937R mutation in the ZNF687 gene. Although the genetic involvement of ZNF687 in PDB has been extensively studied, the molecular mechanisms underlying this association remain unclear. Here, we describe the first Zfp687 knock-in mouse model and demonstrate that the mutation recapitulates the PDB phenotype, resulting in severely altered bone remodeling. Through microcomputed tomography analysis, we observed that 8-month-old mutant mice showed a mainly osteolytic phase, with a significant decrease in the trabecular bone volume affecting the femurs and the vertebrae. Conversely, osteoblast activity was deregulated, producing disorganized bone. Notably, this phenotype became pervasive in 16-month-old mice, where osteoblast function overtook bone resorption, as highlighted by the presence of woven bone in histological analyses, consistent with the PDB phenotype. Furthermore, we detected osteophytes and intervertebral disc degeneration, outlining for the first time the link between osteoarthritis and PDB in a PDB mouse model. RNA sequencing of wild-type and Zfp687 knockout RAW264.7 cells identified a set of genes involved in osteoclastogenesis potentially regulated by Zfp687, e.g., Tspan7, Cpe, Vegfc, and Ggt1, confirming its role in this process. Strikingly, in this mouse model, the mutation was also associated with a high penetrance of hepatocellular carcinomas. Thus, this study established an essential role of Zfp687 in the regulation of bone remodeling, offering the potential to therapeutically treat PDB, and underlines the oncogenic potential of ZNF687.

Traditional Medicinal Plants as a Source of Inspiration for Osteosarcoma Therapy

Osteosarcoma is one of the most common types of bone cancers among paediatric patients. Despite the advances made in surgery, chemo-, and radiotherapy, the mortality rate of metastatic osteosarcoma remains unchangeably high. The standard drug combination used to treat this bone cancer has remained the same for the last 20 years, and it produces many dangerous side effects. Through history, from ancient to modern times, nature has been a remarkable source of chemical diversity, used to alleviate human disease. The application of modern scientific technology to the study of natural products has identified many specific molecules with anti-cancer properties. This review describes the latest discovered anti-cancer compounds extracted from traditional medicinal plants, with a focus on osteosarcoma research, and on their cellular and molecular mechanisms of action. The presented compounds have proven to kill osteosarcoma cells by interfering with different pathways: apoptosis induction, stimulation of autophagy, generation of reactive oxygen species, etc. This wide variety of cellular targets confer natural products the potential to be used as chemotherapeutic drugs, and also the ability to act as sensitizers in drug combination treatments. The major hindrance for these molecules is low bioavailability. A problem that may be solved by chemical modification or nano-encapsulation.

The Osteoclast Traces the Route to Bone Tumors and Metastases

Osteoclasts are highly specialized cells of the bone, with a unique apparatus responsible for resorption in the process of bone remodeling. They are derived from differentiation and fusion of hematopoietic precursors, committed to form mature osteoclasts in response to finely regulated stimuli produced by bone marrow–derived cells belonging to the stromal lineage. Despite a highly specific function confined to bone degradation, emerging evidence supports their relevant implication in bone tumors and metastases. In this review, we summarize the physiological role of osteoclasts and then focus our attention on their involvement in skeletal tumors, both primary and metastatic. We highlight how osteoclast-mediated bone erosion confers increased aggressiveness to primary tumors, even those with benign features. We also outline how breast and pancreas cancer cells promote osteoclastogenesis to fuel their metastatic process to the bone. Furthermore, we emphasize the role of osteoclasts in reactivating dormant cancer cells within the bone marrow niches for manifestation of overt metastases, even decades after homing of latent disseminated cells. Finally, we point out the importance of counteracting tumor progression and dissemination through pharmacological treatments based on a better understanding of molecular mechanisms underlying osteoclast lytic activity and their recruitment from cancer cells.

An update on imaging of Paget's sarcoma

Paget's sarcoma is a rare and particularly aggressive tumour arising within pagetic bone, affecting approximately 1% of patients with Paget's disease during the course of their disease. Most of these tumours are osteosarcomas, but the age profile, skeletal distribution and clinical outcomes differ considerably from conventional osteosarcoma. In this review, we outline the clinical, radiographic/CT, scintigraphic and magnetic resonance imaging features of Paget's sarcoma. We also review the neoplastic and non-neoplastic mimics of Paget's sarcoma that should be considered in the differential diagnosis when encountering an aggressive lesion within pagetic bone.

18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in Malignant Transformation of Paget's Disease of Bone

Malignant transformation Paget's disease of bone to sarcoma is relatively rare, occurring in approximately 1% of these patients. Although few clinical and imaging findings may help in prediction of malignant transformation, most of them are nonspecific. We describe a case of carcinoma vocal cord and Paget's disease of bone with sarcomatous transformation, where ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography was helpful in accurate diagnosis by demonstrating differential intense FDG uptake in transformed areas of pagetic bone and also FDG-avid osteoblastic pulmonary metastasis.

Bisphosphonates in common pediatric and adult bone sarcomas

The therapeutic strategies proposed currently for bone sarcomas are based on neo-adjuvant chemotherapy, delayed en-bloc wide resection, and adjuvant chemotherapy. Unfortunately, bone sarcomas are characterized by high rates of poor drug response, with a high risk of drug resistance, local recurrence and/or a high propensity for induced metastases. The pathogenesis of bone sarcomas is strongly associated with dysregulation of local bone remodeling and increased osteolysis that plays a part in tumor development. In this context, bisphosphonates (BPs) have been proposed as a single agent or in combination with conventional drugs to block bone resorption and the vicious cycle established between bone and sarcoma cells. Pre-clinical in vitro studies revealed the potential "anti-tumor" activities of nitrogen-bisphosphonates (N-BPs). In pre-clinical models, N-BPs reduced significantly primary tumor growth in osteosarcoma and Ewing sarcoma, and the installation of lung metastases. In chondrosarcoma, N-BPs reduced the recurrence of local tumors after intralesional curettage, and increased overall survival. In pediatric and adult osteosarcoma patients, N-BPs have been assessed in combination with conventional chemotherapy and surgery in randomized phase 3 studies with no improvement in clinical outcome. The lack of benefit may potentially be explained by the biological impact of N-BPs on macrophage differentiation/recruitment which may alter CD8⁺-T lymphocyte infiltration. Thanks to their considerable affinity for the mineralized extracellular matrix, BPs are an excellent platform for drug delivery in malignant bone sites with reduced systemic toxicity, which opens up new opportunities for their future use.

The Loss of Profilin 1 Causes Early Onset Paget's Disease of Bone

Paget's disease of bone (PDB) is a late-onset disorder frequently caused by mutations in the SQSTM1 gene, leading to hyperactive osteoclasts and resulting in bone pain, deformities, and fractures. However, some more severe forms of PDB-negative for SQSTM1 mutations-have been described, in which the disease degenerates into bone cancers and shows a poor prognosis. Osteosarcoma is the most frequent and aggressive tumor arising in PDB (OS/PDB), with a 5-year survival rate almost nil, but the underlying molecular mechanism is unknown. Here, we investigated an extended pedigree with 11 individuals affected by early onset and polyostotic PDB, mainly interesting the appendicular skeleton. Interestingly, three members also developed secondary osteosarcoma. We performed exome sequencing and identified a 4-bp deletion in the PFN1 gene, resulting in the degradation of the mutant protein. Copy number screening on 218 PDB individuals of our biobank disclosed that four of them (~2%) carry a germline heterozygous deletion of PFN1. The identification of these subjects, who exhibit a particularly severe form of disease, emphasizes the diagnostic value of this genetic screening to identify PDB individuals predisposed to develop osteosarcoma. In fact, we detected allelic imbalance at PFN1 locus also in 8 of 14 (57%) sporadic OS/PDB, further proving its causative role. in vitro experiments also confirmed PFN1 involvement in this form of PDB. Indeed, CRISPR-Cas9-mediated Pfn1 knockout in pre-osteoclasts resulted into enhanced osteoclast differentiation and resorption, with the formation of large osteoclasts never described before in PDB. In addition, Pfn1 lacking pre-osteoblasts lost their differentiation capability and failed to efficiently mineralize bone. Moreover, they acquired features of malignant transformation, including loss of focal adhesions and increased invasion ability. In conclusion, these findings disclose PFN1 haploinsufficiency as the pathological mechanism in OS/PDB. © 2020 American Society for Bone and Mineral Research.

Craniofacial Manifestations of Systemic Disorders: CT and MR Imaging Findings and Imaging Approach

Many systemic diseases or conditions can affect the maxillofacial bones; however, they are often overlooked or incidentally found at routine brain or head and neck imaging performed for other reasons. Early identification of some conditions may significantly affect patient care and alter outcomes. Early recognition of nonneoplastic hematologic disorders, such as thalassemia and sickle cell disease, may help initiate earlier treatment and prevent serious complications. The management of neoplastic diseases such as lymphoma, leukemia, or Langerhans cell histiocytosis may be different if diagnosed early, and metastases to the maxillofacial bones may be the first manifestation of an otherwise occult neoplasm. Endocrinologic and metabolic disorders also may manifest with maxillofacial conditions. Earlier recognition of osteoporosis may alter treatment and prevent complications such as insufficiency fractures, and identification of acromegaly may lead to surgical treatment if there is an underlying growth hormone-producing adenoma. Bone dysplasias sometimes are associated with skull base foraminal narrowing and subsequent involvement of the cranial nerves. Inflammatory processes such as rheumatoid arthritis and sarcoidosis may affect the maxillofacial bones, skull base, and temporomandibular joints. Radiologists should be familiar with the maxillofacial computed tomographic and magnetic resonance imaging findings of common systemic disorders because these may be the first manifestations of an otherwise unrevealed systemic process with potential for serious complications. Online supplemental material is available for this article. ^©RSNA, 2018.

Primary leiomyosarcoma of the bone: a case report and a review of the literature

RATIONALE

Leiomyosarcoma (LMS) is a malignant sarcoma that can occur in different anatomic sites, including the bone, showing similar histological characteristics but heterogeneous clinical behavior and prognosis. Primary bone LMS was first described in 1965. It is a very rare sarcoma, accounting for <0.7% of all primary malignant bone tumors.

PATIENT CONCERNS

We report the case of a 52-year-old male with primary bone LMS who presented with a solitary osteolytic lesion with focal cortical destruction in the left clavicle, seen on an x-ray and subsequent computed tomography (CT) scan.

DIAGNOSIS

The multidisciplinary Osteoncology team of our institute planned a biopsy that revealed the presence of spindle and pleomorphic cells with a positive reaction for smooth muscle actin and desmin at immunohistochemical analysis, without the presence of cartilage or bone matrix. These results were consistent with a high-grade malignant LMS arising from the bone.

INTERVENTIONS

Complete surgical resection of the tumor was performed and a decision was made with the patient not to proceed with adjuvant chemotherapy or radiotherapy.

OUTCOMES

After more than 1 year of surgery, the patient is well, with no evidence of recurrent or metastatic disease. Follow-up is ongoing.

LESSONS

Little is known about the biology and clinical behavior of bone LMS due to its extreme rarity. A multidisciplinary team in a specialized center is needed for the optimal management of the disease. Surgery with a curative intent is the cornerstone of treatment of localized disease. No data are available about chemotherapy in neoadjuvant, adjuvant, or advanced settings. Further research is needed to identify more effective therapies.

Survival and prognostic factors in Chinese patients with osteosarcoma: 13-year experience in 365 patients treated at a single institution

This study was designed to retrospectively analyze the survival and prognostic factors in Chinese osteosarcoma patients received neoadjuvant chemotherapy or/and surgery in a single institution. A total of 365 patients with pathological proved osteosarcoma undergoing neoadjuvant chemotherapy or/and surgery in a single institution between December 1999 and December 2012 were retrospectively analyzed for the demographic, tumor-related, and treatment-related variables, prognostic factors for survival rate and chemotherapy response. There were 231 males and 134 females (ratio, 1.72:1). The average age was 21±10years, with peak age between 10 and 20 years old (62%, 226/365). Of 365 patients, 319 (87.4%) suffered from primary tumor only, and 46 (12.6%) had metastases upon initial presentation. The overall 5-year survival rate was 65%. Upon univariate analysis, tumor site (femur 60.3%; other long bone 70.2%; trunk 33.6%; P=0.012), primary metastases (yes 36.7%; no 68.9%; P=0.000), tumor response to preoperative chemotherapy (good 89.8%; poor 47.5%; P=0.001) and recurrence/metastases after treatment (yes 36.2%; no 63.8%; P=0.000) were associated with higher 5-year survival rate. All factors except tumor site maintained their significance in multivariate testing. Male sex and nonconventional subtype of tumor were related to a higher likelihood of poor chemotherapy response.The absence of metastases at initial presentation, negative local recurrence or metastases after treatment, and tumor response to chemotherapy are of independent prognostic value in osteosarcoma. The overall prognostic factors and survival in Chinese patients are similar to those patients reported in western countries.

Osteosarcoma of the pelvis

Aims

Osteosarcoma of the pelvis is a particularly difficult tumour to treat as it often presents late, may be of considerable size and/or associated with metastases when it presents, and is frequently chondroid in origin and resistant to chemotherapy. The aim of this study was to review our experience of managing this group of patients and to identify features predictive of a poor outcome.

Patients and Methods

Between 1983 and 2014, 121 patients, (74 females and 47 males) were treated at a single hospital: 74 (61.2%) patients had a primary osteosarcoma and 47 (38.8%) had an osteosarcoma which was secondary either to Paget’s disease (22; 18.2%) or to previous pelvic irradiation (25; 20.7%). The mean age of those with a primary osteosarcoma was 29.3 years (nine to 76) and their mean follow-up 2.9 years (0 to 29). The mean age of those with a secondary sarcoma was 61.9 years (15 to 85) and their mean follow-up was one year (0 to 14). A total of 22 patients with a primary sarcoma (52.4%) and 20 of those with a secondary sarcoma (47.6%) had metastases at the time of presentation.

Results

The disease-specific survival at five years for all patients was 27.2%. For those without metastases at the time of diagnosis, the five-year survival was 32.7%. Factors associated with a poor outcome were metastases at diagnosis and secondary tumours. In primary osteosarcoma, sacral location, surgical margin and a diameter > 10 cm were associated with a poor outcome.

Conclusion

In this, the largest single series of patients with an osteosarcoma of the pelvis treated in a single hospital, those with secondary tumours and those with metastases at presentation had a particularly poor outcome. For those with a primary sarcoma, sacral location, an intralesional margin and a diameter of > 10 cm were poor prognostic indicators. Cite this article: Bone Joint J 2016;98-B:555–63.

Comparative Aspects of Osteosarcoma Pathogenesis in Humans and Dogs

Osteosarcoma (OS) is a primary and aggressive bone sarcoma affecting the skeleton of two principal species, human beings and canines. The biologic behavior of OS is conserved between people and dogs, and evidence suggests that fundamental discoveries in OS biology can be facilitated through detailed and comparative studies. In particular, the relative genetic homogeneity associated with specific dog breeds can provide opportunities to facilitate the discovery of key genetic drivers involved in OS pathogenesis, which, to-date, remain elusive. In this review, known causative factors that predispose to the development OS in human beings and dogs are summarized in detail. Based upon the commonalities shared in OS pathogenesis, it is likely that foundational discoveries in one species will be translationally relevant to the other and emphasizes the unique opportunities that might be gained through comparative scientific approaches.

Paget's sarcoma of the patella

Paget's sarcoma is a rare complication of Paget's disease and isolated Paget's disease of the patella is extremely rare. We describe a unique case of Paget's sarcoma of the patella in a 69-year-old male farmer who had a remote history of a fracture in the same patella 40 years previously. In this case, imaging and pathogenesis of Paget's disease of bone is described and factors implicated in the development of Paget's disease in this patient are evaluated.

Osteogenic tumors of bone

In this paper we provide an overview of benign and malignant osteogenic bone tumors. We describe the diagnostic features, radiographic findings, and pertinent ancillary studies needed to diagnose these bone-forming lesions. We begin with osteoid osteoma and osteoblastoma, which are histologically bland and eminently benign with rare possible exceptions. On the other end of the behavioral spectrum is osteosarcoma, which encompasses many subtypes ranging from high-grade osteogenic osteosarcoma to less overtly osteogenic lesions such as telangiectatic and small cell osteosarcoma. While classic osteogenic osteosarcoma can be easily recognized by its high grade morphology and formation of extracellular lace-like osteoid, its variants may pose diagnostic dilemmas as their differential diagnoses can include benign, fibrous, and vascular lesions, among others. Recognition of these variants is essential to avoid diagnostic pitfalls. In equivocal cases, some forms of osteosarcoma have shown molecular alterations that may prove diagnostically useful.

Paget's disease of bone

Paget's disease is an osteoclastic-mediated disorder of bone that results in abnormal bone resorption associated with inadequate remodeling that leads to mechanically weakened bone. Demonstrating variable geographic prevalence, it is becoming less frequent and age of onset is lengthening in areas of once high prevalence prior to the institution of effective medical therapies, suggesting its etiology involves both environmental as well as genetic factors. Insights into its pathophysiology are helping to clarify other inherited osteolytic disorders of bone by providing additional insights into related cellular processes.

Genotype-phenotype correlation in juvenile Paget disease: role of molecular alterations of the TNFRSF11B gene

Juvenile Paget disease (JPD) {MIM 239000} is a rare inherited bone disease that affects children. The patients affected with JPD present an altered bone turnover, therefore, show a phenotype characterized by progressive bone deformities, fractures, and short stature. Deletions or missense mutations of the TNFRSN11B gene are common in these children. This gene encodes a soluble protein, the osteoprotegerin, which leads to uncontrolled osteoclastogenesis when mutated. JPD is characterized by a strong genotype-phenotype correlation, so depending on the alteration of the TNFRSN11B gene, the phenotype is variable. This review describes the different clinical features which are characteristic of JPD and the correspondence with the different molecular alterations of the TNFRSN11B gene.

Osteosarcoma models: from cell lines to zebrafish

High-grade osteosarcoma is an aggressive tumor most commonly affecting adolescents. The early age of onset might suggest genetic predisposition; however, the vast majority of the tumors are sporadic. Early onset, most often lack of a predisposing condition or lesion, only infrequent (<2%) prevalence of inheritance, extensive genomic instability, and a wide histological heterogeneity are just few factors to mention that make osteosarcoma difficult to study. Therefore, it is sensible to design and use models representative of the human disease. Here we summarize multiple osteosarcoma models established in vitro and in vivo, comment on their utilities, and highlight newest achievements, such as the use of zebrafish embryos. We conclude that to gain a better understanding of osteosarcoma, simplification of this extremely complex tumor is needed. Therefore, we parse the osteosarcoma problem into parts and propose adequate models to study them each separately. A better understanding of osteosarcoma provides opportunities for discovering and assaying novel effective treatment strategies.

“Sometimes the model is more interesting than the original disease”

PJ Hoedemaeker (1937–2007).

Osteosarcoma: Differential Diagnostic Considerations

Accurate diagnosis of bone-forming tumors, including correct subclassification of osteogenic sarcoma is critical for determination of appropriate clinical management and prediction of patient outcome. The morphologic spectrum of osteogenic sarcoma is extensive, however, and its histologic mimics are numerous. This review focuses on the major differential diagnoses of the specific subtypes of osteosarcoma, presents summaries of various diagnoses, and provides tips to overcoming pitfalls in diagnosis.

Paget’s disease: clinical update

Paget’s disease is a chronic disorder of bone remodeling, characterized by an abnormal increase of osteoclast and, hence, osteoblast activity. The imbalance of bone turnover results in the formation of unhealthy and fragile bone. It also leads to impairment of adjacent joints and to a risk of various complications. Current research focuses on the elucidation of the etiologic role viral infection and predisposing genetic factors. Paget’s disease is commonly discovered by chance; its suspicion is raised either by high level of alkaline phosphatase or by the X-ray of the pathological bone. Bisphosphonates have proven to be effective in controlling disease activity because they inhibit osteoclast function. Their use is recommended when bone-derived serum alkaline phosphatase is high and/or when disease localizations are highly suspected for the development of complications. Orv. Hetil., 2011, 152, 1337–1346.

Bone and soft tissue tumors of hip and pelvis

Objective is to identify epidemiologic and radiologic criteria allowing specific diagnoses of tumors and tumor-like lesions in the hip region and pelvis, and to optimize pre-operative staging. Patients with pelvic tumors are usually older, and their tumors are larger relative to patients with tumors in extremities. The majority of tumors in the pelvis are malignant (metastases, myeloma, chondrosarcoma, Ewing-, osteo-, and MFH/fibrosarcoma), while those in the proximal femur are in majority benign (fibrous dysplasia, solitary bone cyst, and osteoid osteoma). Soft tissue masses in the thigh in the elderly are typically sarcomas without tumor specific signs. Common tumor-like lesions occurring in the hip and pelvis that can mimic neoplasm are: infections (including tuberculosis), insufficiency/avulsion fractures, cysts, fibrous dysplasia, aneurysmal bone cyst, Langerhans cell histiocytosis, and Paget's disease. Local MR staging is based on the compartmental anatomy. The psoas and gluteal muscles are easily invaded by sarcoma originating in the ileum. The pectineus muscle protects the neurovascular bundle at the level of the hip. The thigh is separated into three compartments, some structures (Sartorius muscle) cross borders between compartments. Immobile joints (SI-joints, osteoarthritic hip) are relatively easily crossed by sarcoma and giant cell tumor.

Osteoblastic osteosarcoma in monostotic Paget's disease

Paget's disease is a disorder of bone remodelling affecting 1-2% of the general population, most frequently men over 50 years of age. Sarcomatous degeneration occurs in 0.1-0.95% of patients with Paget's disease. It can be observed in monostotic and polyostotic disease. Osteosarcomas account for more than 80% of pagetic sarcomas; osteoblastic pagetic osteosarcomas are rare. In this article, we present the case of a 75-year-old man with secondary osteosarcoma arising in monostotic Paget's disease, initially misdiagnosed as rotator cuff tendinopathy. Imaging studies and biopsy were diagnostic.

The role of surgery and adjuvants to survival in Pagetic osteosarcoma

BACKGROUND

Osteosarcoma is a rare complication of Paget's disease with a very poor prognosis. Treatment is controversial: the older age of the patients affected by Paget's disease may limit the use of chemotherapy and axial involvement may limit the practicality of surgery.

QUESTIONS/PURPOSES

The purposes of this study are (1) to report the survival in patients treated for osteosarcoma in Paget's disease; (2) to identify correlations between type of treatment and survival comparing our data with those in the literature; (3) to determine if the extent of Paget's disease and risk of malignant transformation are associated; (4) to assess if prognosis is related with site; and (5) to identify the variations of histologic subtypes of these osteosarcomas.

METHODS

We retrospectively reviewed the medical records of 26 patients treated between 1961 and 2006 who had bone sarcoma arising from a site of Paget's disease. Twenty two of the 26 patients had surgery. In six surgery only was performed; three had surgery, adjuvant chemotherapy, and radiotherapy; one surgery and radiotherapy; 12 underwent surgery and chemotherapy, adjuvant in 10 patients and neoadjuvant in two; two had only radiotherapy and two had only chemotherapy. We performed survival analyses between various combinations of treatment.

RESULTS

At last followup four patients had no evidence of disease (NED) at a minimum followup of 42.6 months (mean, 139 months; range, 42.6-257.4 months) and 22 died with disease (DWD) at a minimum time of 1 month (mean, 20.2 months; range, 1-84 months). One of the six patients (11%) treated with surgery only had NED at 10 years; the other five died from disease at a mean of 30 months. Three of 12 patients (25%) treated with surgery and chemotherapy are NED at a mean followup of 12 years; nine died of disease at a mean of 24 months. All patients treated without surgery died at a mean of 7.5 months (range, 1-13.7 months).

CONCLUSIONS

Despite improvements in surgery and medical treatments the prognosis remains poor in patients with Paget's sarcoma.

The epidemiology of osteosarcoma

Osteosarcoma derives from primitive bone-forming mesenchymal cells and is the most common primary bone malignancy. The incidence rates and 95% confidence intervals of osteosarcoma for all races and both sexes are 4.0 (3.5-4.6) for the range 0-14 years and 5.0 (4.6-5.6) for the range 0-19 years per year per million persons. Among childhood cancers, osteosarcoma occurs eighth in general incidence and in the following order: leukemia (30%), brain and other nervous system cancers (22.3%), neuroblastoma (7.3%), Wilms tumor (5.6%), Non-Hodgkin lymphoma (4.5%), rhabdomyosarcoma (3.1%), retinoblastoma (2.8%), osteosarcoma (2.4%), and Ewing sarcoma (1.4%). The incidence rates of childhood and adolescent osteosarcoma with 95% confidence intervals areas follows: Blacks, 6.8/year/million; Hispanics, 6.5/year/million; and Caucasians, 4.6/year/million. Osteosarcoma has a bimodal age distribution, having the first peak during adolescence and the second peak in older adulthood. The first peak is in the 10-14-year-old age group, coinciding with the pubertal growth spurt. This suggests a close relationship between the adolescent growth spurt and osteosarcoma. The second osteosarcoma peak is in adults older than 65 years of age; it is more likely to represent a second malignancy, frequently related to Paget's disease. The incidence of osteosarcoma has always been considered to be higher in males than in females, occurring at a rate of 5.4 per million persons per year in males vs. 4.0 per million in females, with a higher incidence in blacks (6.8 per million persons per year) and Hispanics (6.5 per million), than in whites (4.6 per million). Osteosarcoma commonly occurs in the long bones of the extremities near the metaphyseal growth plates. The most common sites are the femur (42%, with 75% of tumors in the distal femur), the tibia (19%, with 80% of tumors in the proximal tibia), and the humerus (10%, with 90% of tumors in the proximal humerus). Other likely locations are the skull or jaw (8%) and the pelvis (8%). Cancer deaths due to bone and joint malignant neoplasms represent 8.9% of all childhood and adolescent cancer deaths. Death rates for osteosarcoma have been declining by about 1.3% per year. The overall 5-year survival rate for osteosarcoma is 68%, without significant gender difference. The age of the patient is correlated with the survival, with the poorest survival among older patients. Complete surgical excision is important to ensure an optimum outcome. Tumor staging, presence of metastases, local recurrence, chemotherapy regimen, anatomic location, size of the tumor, and percentage of tumor cells destroyed after neoadjuvant chemotherapy have effects on the outcome.

Primary leiomyosarcoma of extragnathic bone: clinicopathologic features and reevaluation of prognosis

CONTEXT

Leiomyosarcoma most commonly involves the female genital tract and occasionally arises within the retroperitoneum, abdominal cavity, or the soft tissues of the extremity. Presentation as a primary bone tumor is extraordinarily uncommon, potentially leading to misdiagnosis. The prognosis is traditionally thought to be dismal. However, this conclusion is largely based on individual case reports and small series, in some of which the pathologic diagnosis is not well documented.

OBJECTIVE

To review the clinicopathologic features of well-established cases of primary skeletal leiomyosarcoma and reevaluate the prognostic implications thereof.

DATA SOURCES

A National Center for Biotechnology Information PubMed search of the English language literature identified 104 authenticated cases of primary leiomyosarcoma of extragnathic bone. An additional 3 cases are reported and illustrated herein.

CONCLUSIONS

Approximately half of all patients with primary skeletal leiomyosarcoma either presented with metastatic disease or developed metastases within 1 year of diagnosis. The 5-year overall and disease-free survival rates were 59% and 41%, respectively, comparable to that of other skeletal sarcomas. As for other bone and soft tissue sarcomas, high histologic grade and tumor stage are predictive of poor outcome.

Neurologic complications of Paget disease of bone

OBJECTIVE

To review the epidemiology, evaluation, and management of the neurologic complications associated with Paget disease of bone (PDB).

METHODS

We reviewed the English-language medical literature using MEDLINE data sources from 1950 to August 2008 and manually searched cross-references from original articles and reviews. Search terms included "Paget* disease of bone" and "neurologic* complications," "cranial nerve," "spinal cord," or "peripheral nerve."

RESULTS

Several neurologic problems in the central and peripheral nervous systems may complicate PDB. Up to 76% of patients may have some form of neurologic involvement. Neurologic complications can occur in patients with a long history of PDB as well as in patients with previously unrecognized disease. The primary mechanisms of nerve damage in PDB involving the spine are ischemic myelitis and compression due to bone hypertrophy. Evaluation includes determining the serum alkaline phosphatase level and imaging by radiography, bone scintigraphy, computed tomographic scanning, and, for lesions of the central nervous system, magnetic resonance imaging. If a soft-tissue mass is found, biopsy should be considered to exclude the presence of sarcoma. Treatment strategies include calcium, vitamin D, bisphosphonates, and possibly surgical intervention for refractory cases.

CONCLUSION

Neurologic sequelae of PDB may be underappreciated. Despite the paucity of data guiding treatment, zoledronic acid is a reasonable first-line therapy. Lack of response to treatment or relapse should prompt diagnostic reevaluation with a heightened suspicion for tumor.

Sarcoma arising in Paget's disease of bone: declining incidence and increasing age at presentation

BACKGROUND

Paget's disease is presenting at older ages, with a trend to monostotic disease, associated with lower serum total alkaline phosphatase (serum total ALP) levels. Sarcomatous transformation is a rare complication, which only half a century ago had a median age of presentation of less than 60 years. We have investigated whether sarcomatous change exhibits increasing age at presentation, whether the trend to monostotic Paget's disease exists, whether male predominance in sarcoma still continues and explored factors that might affect survival.

METHODS

Notes of all patients from the Royal Orthopaedic Hospital, Birmingham primary malignant bone tumour registry were reviewed and all cases of Pagetic sarcoma since 1975 extracted. In addition to basic demographic data, mode of presentation, skeletal involvement by Paget's disease, history of treatment, presence of pulmonary metastases, serum total ALP levels and survival were obtained.

RESULTS

Unequivocal Pagetic sarcoma was identified in 32 patients (23 M, 9 F). Age at presentation was 73.8 years with no sex difference and with known pre-existing Paget's disease in 42%. Only 15% had received any specific Paget's disease treatment. Serum total ALP was not invariably markedly elevated (compared with non-sarcomatous disease) and was related to the number of skeletal sites, but not to the sarcoma histological subtype. Paget's disease was monostotic in 46%. Pagetic sarcoma fell from 23% to 8% of primary bone sarcoma referrals in patients aged over 50 years between the decades 1986-1995 and 1996-2005. Median survival remained poor at 0.66 years. Survival of greater than 2 years occurred in 4 patients, one of whom with a low grade Pagetic sarcoma being alive at 12 years follow up.

CONCLUSIONS

The proportion of Paget's disease patients with sarcoma has fallen steadily since Paget's original report and is now about 0.3%, the decline predating availability of effective therapy. Sarcoma is not necessarily associated with very high serum total ALP. It is present amongst polyostotic cases in the expected proportion suggesting that more widespread skeletal involvement by Paget's disease is not a significant risk factor for malignant transformation. Sarcoma is presenting later concurrent with the advancing age of non-malignant disease, but male predominance continues. Pagetic sarcoma is now rare, continues to have a poor prognosis and is often the presenting feature of the disease.

Paget's disease of bone: histologic analysis of 754 patients

Although Paget's disease of bone (PDB) is the second most common metabolic bone disease, to our knowledge, there is only one quantitative analysis on the histological and especially on the histomorphometric level. Therefore, the aim of this study was to analyze, on the basis of the Hamburg Bone Register, PBD in terms of incidence, skeletal distribution, malignant transformation, and histological and histomorphometric characteristics. Bone biopsies and patient files of 754 cases with histologically proven PDB were reviewed in a retrospective study. Quantitative static histomorphometry was performed on a representative subgroup of 247 biopsies derived from patients with manifestation of PDB at the iliac crest and compared with an age- and sex-matched control group. The peak incidence of PDB was between 70 and 80 yr of age. The majority of monostotic skeletal manifestation was localized at the os ilium, followed by the spine and femur. Histomorphometric results showed a high bone turnover with a significant increase in bone resorption and bone formation indices leading to an increased bone volume. Paget sarcoma was diagnosed in 6 of 754 patients, indicating a malignant transformation in 0.8% of the affected patients. Taken together, our study characterizes PDB in Germany on the basis of one of the largest cohorts of patients with histologically proven PDB. Moreover, for the first time, a quantitative histomorphometric approach was taken for >200 cases, where we could show local high bone mass lesions as a result of an increase of both osteoclast and osteoblast indices.

Osteogenic sarcoma (osteosarcoma) in the elderly: tumor delineation and predisposing conditions

Osteogenic sarcoma (OS), the most common primary bone cancer, is conventionally a primary intramedullary (conventional OS) high-grade malignant tumor characterized by malignant cells forming immature bone or osteoid. The age distribution data for primary bone sarcomas are bimodal. OS is largely a disease of the young but about one-third of OS occurs in patients over 40 years of age. Thus, though considered as rare occurrences, bone tumors occur also in the geriatric population. In this report, tumor delineation and the significance of predisposing conditions to the occurrence of OS are reviewed.