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

The Decline of Paget's Disease of Bone and Domestic Coal Use-A Hypothesis

The cause of Paget's disease of bone (PDB) is unknown. It emerged as a distinct entity in Britain in the late nineteenth century when it was prevalent, and florid presentation not uncommon. Epidemiological surveys in the 1970s showed that Britain had a substantially higher prevalence of PDB than any other country. Studies in the late twentieth and early twenty-first centuries have documented an unexplained change in presentation, with a greatly reduced prevalence and less severe disease than formerly. The emergence of PDB in Britain coincided with rapid industrialization which, in turn, was driven by the use of coal for energy. In the home, bituminous coal was customarily burnt on an open hearth for heating. Using data on coal production, population size, and estimates of domestic use, the estimated exposure to domestic coal burning rose threefold in Britain during the nineteenth century and began to fall after 1900. This pattern fits well with the decline in PDB documented from death certification and prevalence surveys. Colonists moving from Britain to North America, Australia and New Zealand established coal mines and also used coal for domestic heating. PDB was found in these settler populations, but was largely absent from people indigenous to these lands. In all parts of the world PDB prevalence has fallen as the burning of coal in open hearths for domestic heating has reduced. The nature of the putative factor in coal that could initiate PDB is unknown, but possible candidates include both organic and inorganic constituents of bituminous coal.

Drug treatment strategies for Paget's disease: relieving pain and preventing progression

INTRODUCTION

Paget's disease of bone (PDB) is a focal bone disorder caused by a marked dysregulation of osteoblasts and osteoclasts in basic multicellular units, leading to abnormal and disorganized deposition of collagen fibers (the so-called "woven bone"). Therefore, pagetic bones are increased in size, and at increased risk for bone pain, deformities, fractures, osteoarthritis, and, more rarely, neoplastic degeneration.

AREAS COVERED

In this review we revise the available information concerning the pharmacological treatment of PDB.

EXPERT OPINION

PDB progresses slowly within the affected skeletal sites and, if untreated, often leads to bone overgrowth, with bone pain, deformity and a likely increased risk of complications. Thus, the primary goal of treatment is the restoration of a normal bone turnover, in order to relieve bone pain or other symptoms and possibly prevent the complications. PDB long remained a poorly treatable disorder until the discovery of antiresorptive agents such as calcitonin first and bisphosphonates (BPs) later. With the recent development of potent intravenous BPs like zoledronate, allowing a better control of disease activity over the long term with a single infusion, has contributed to a marked improvement of the clinical management of this invalidating disorder.

Premalignant Conditions of Bone

Development of malignancy is a multifactorial process, and there are multitude of conditions of bone that may predispose patients to malignancy. Etiologies of malignancy include benign osseous conditions, genetic predisposition, and extrinsic conditions. New-onset pain or growth in a previously stable lesion is that should concern for malignant change and should prompt a diagnostic workup for malignancy.

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.

[Paget's disease of bone-a current review of clinical aspects, diagnostics and treatment]

Paget's disease is a monostotic or polyostotic progressive skeletal disease with a genetic predisposition. The affected bone areas show osseous swelling and often grotesque deformation, chronic pain and fractures. Many cases are asymptomatic for a long time resulting in a late diagnosis. The pathogenesis is still unknown. In addition to a genetic predisposition, viral factors are also discussed. Laboratory tests and imaging are used for diagnosis. The effective principle of medicinal bisphosphonate treatment is to inhibit osteoclastic bone resorption and should be initiated early to prevent secondary complications. This article presents the current knowledge about this rare osteological disease.

Mutation of PFN1 Gene in an Early Onset, Polyostotic Paget-like Disease

CONTEXT

Paget disease of bone (PDB) is a metabolic bone disease whose genetic cause remains unknown in up to 50% of familial patients.

OBJECTIVE

Our aim was to investigate the underlying genetic defect in a large pedigree with a severe, early onset, autosomal dominant form of PDB across 3 generations.

METHODS

Whole exome sequencing was performed in affected and unaffected family members, and then mutation screening was replicated in a sample of PDB patients with early-onset, polyostotic PDB.

RESULTS

We identified a frameshift D107Rfs*3 mutation in PFN1 (encoding for profilin 1, a highly conserved regulator of actin-polymerization and cell motility) causing the truncation of the C-terminal part of the protein. The mutation was also detected in a 17-year-old asymptomatic family member who upon biochemical and radiological analyses was indeed found to be affected. Sequencing of the entire PFN1 coding region in unrelated PDB patients identified the same mutation in 1 patient. All mutation carriers had a reduced response to bisphosphonates, requiring multiple zoledronate infusions to control bone pain and achieve biochemical remission over a long term. In vitro osteoclastogenesis in peripheral blood mononuclear cells (PBMCs) from mutation carriers showed a higher number of osteoclasts with PDB-like features. A similar phenotype was observed upon PFN1 silencing in murine bone marrow-derived monocytes, suggesting that the frameshift PFN1 mutation confers a loss of function in profilin 1 activity that induces PDB-like features in the osteoclasts, likely due to enhanced cell motility and actin ring formation.

CONCLUSIONS

Our findings indicate that PFN1 mutation causes an early onset, polyostotic PDB-like disorder.

Diagnosis and Management of Paget's Disease of Bone in Adults: A Clinical Guideline

An evidence-based clinical guideline for the diagnosis and management of Paget's disease of bone (PDB) was developed using GRADE methodology, by a Guideline Development Group (GDG) led by the Paget's Association (UK). A systematic review of diagnostic tests and pharmacological and nonpharmacological treatment options was conducted that sought to address several key questions of clinical relevance. Twelve recommendations and five conditional recommendations were made, but there was insufficient evidence to address eight of the questions posed. The following recommendations were identified as the most important: 1) Radionuclide bone scans, in addition to targeted radiographs, are recommended as a means of fully and accurately defining the extent of metabolically active disease in patients with PDB. 2) Serum total alkaline phosphatase (ALP) is recommended as a first-line biochemical screening test in combination with liver function tests in screening for the presence of metabolically active PDB. 3) Bisphosphonates are recommended for the treatment of bone pain associated with PDB. Zoledronic acid is recommended as the bisphosphonate most likely to give a favorable pain response. 4) Treatment aimed at improving symptoms is recommended over a treat-to-target strategy aimed at normalizing total ALP in PDB. 5) Total hip or knee replacements are recommended for patients with PDB who develop osteoarthritis in whom medical treatment is inadequate. There is insufficient information to recommend one type of surgical approach over another. The guideline was endorsed by the European Calcified Tissues Society, the International Osteoporosis Foundation, the American Society of Bone and Mineral Research, the Bone Research Society (UK), and the British Geriatric Society. The GDG noted that there had been a lack of research on patient-focused clinical outcomes in PDB and identified several areas where further research was needed. © 2019 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.

Paget's disease of bone

Paget's disease is a chronic focal high turnover bone disorder that is primarily present in middle-aged or older adults. It seems to be restricted to humans and has no clear parallels with other diseases. Although much has been learnt about its pathology and epidemiology, and treatment is now highly effective we still lack a complete understanding of its etiology and biology. This review focusses on the natural history of the disorder, in particular its changing epidemiology, recent discoveries about its genetic basis and current approaches to diagnosis and treatment. While there is strong evidence for genetic predisposition to Paget's disease, there is also compelling evidence that it is becoming less prevalent, the age of patients at presentation is increasing and that the extent of skeletal involvement is diminishing, implying that there is an important, but as yet unidentified, environmental factor in its etiology. Contemporary patients are typically elderly and have few bones involved. Treatment with potent intravenous bisphosphonates provides prolonged remission and many will require only once in a lifetime treatment.

[Paget's disease of bone: Diagnostic and therapeutic updates]

Paget's disease of bone is the second most common metabolic bone disease after osteoporosis. Its pathogenesis is not yet clearly understood. Geographic distribution and epidemiological variations suggest a role of genetic and environmental factors in its pathophysiology. The frequency of the Paget's disease of bone increases with age. Its discovery can be fortuitous. Prognosis mainly depends on the occurrence of complications involving bones and joints, neurological, cardiovascular or metabolic systems. Treatment of symptomatic forms currently relies on bisphosphonates that have transformed its prognosis.

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.

MR Imaging Findings of Paget's Disease of the Spine

Paget's disease (PD) is a common bone disorder of the aging population where the spine is the second most common involved location after the pelvis. Though imaging findings are well described on CT and radiographs, recognition on MRI can be challenging. We reviewed 16 cases with radiologic or histologic confirmation of uncomplicated PD of the spine. In most cases, MRI showed a mixed pattern of increased/ decreased T1 signal (fine trabecular or coarse) of the vertebral bodies. There was also associated band-like decreased T1 and T2 signal of the endplates. This correlates with the mixed osteolytic and blastic phase of the disease, the most common phase in the spine. Subtle or conspicuous "picture-frame" appearance may also be identified. Present in most cases, but frequently overlooked manifestation on MRI, was the expansion of the vertebral body and/or posterior elements/ spinous process. We identified a subtle diffuse decreased T1 and T2 bone marrow signal, not corresponding to sclerosis on CT or radiographs, in two cases. We proposed this, as an earliest sign on MRI, likely representing early fibro-vascular bone marrow transformation and to our knowledge not previously described. Less commonly, sclerotic PD was also found which is perhaps the most difficult to evaluate given its broad differential. Most cases of PD of the spine were overlooked or confused with other entities by the radiologists. Interpretation of MR images of the spine in the absence of prior imaging is not uncommon. Thus, recognition of MRI manifestations is important to allow appropriate management, to avoid misinterpretations and in most cases to avoid biopsy.

Clinical characteristics and evolution of giant cell tumor occurring in Paget's disease of bone

Patients with Paget's bone disease (PDB) have an increased risk of developing giant cell tumor (GCT). This study was performed to evaluate the clinical characteristics and evolution of GCT complicating PDB and to compare these clinical characteristics to those observed in two large PDB cohorts, the PDB Italian Registry and the United Kingdom's Multi-Centre Randomised Controlled Trial of Symptomatic Versus Intensive Bisphosphonate Therapy for Paget's Disease (PRISM) study. A systematic literature review identified 117 cases of PDB complicated by GCT (PDB-GCT), which involved the skeletal sites affected by PDB (110 patients) or the extraskeletal tissues adjacent to affected bones (7 patients). In contrast to what previously reported for GCT patients without GCT patients (83.2%) were white and one-fourth of them (24.8%) had multifocal GCTs. Compared to PDB patients without GCT, PDB-GCT patients showed a higher male/female ratio (2.1 versus 1.2) and more severe disease (age at PDB onset 52.1 ± 12.1 versus 63.3 ± 10.6 years; number of affected sites 6.1 ± 2.9 versus 2.34 ± 1.6; prevalence of polyostotic PDB 93.3% versus 60.6%). The mortality rate of PDB-GCT patients was higher than those occurring in GCT patients without PDB (about 50% versus 0% to 5% at 5 years) or in PDB patients without GCT (log rank = 29.002). Moreover, up to 98% of PDB-GCT cases had elevated total alkaline phosphatase levels at neoplasm diagnosis, suggestive of active PDB. Importantly, PDB-GCT patients from Southern Italy (45.6% of all GCT patients) showed a higher prevalence of multifocal GCT (51.7%) and of positive familial history for PDB (70.8%) and GCT (65.0%). Finally, indirect evidence suggests a decline in the incidence of GCT in PDB patients. The occurrence of GCT in PDB patients is associated with severe disease and reduced life expectancy of affected patients. The increased prevalence of familial diseases in PDB-GCT patients from Southern Italy suggests a founder effect. The observed changes over time in the incidence of GCT in PDB patients could be related to improved clinical management and/or living conditions of patients.

Osteosarcomas in the upper distal extremities: are their oncological outcomes similar to other sites?

AIMS

To investigate whether the oncological outcomes of patients with osteosarcomas in the upper distal extremity are similar to other sites and assess if limb-salvage surgery is safe in this location.

METHODS

The centre database was used to identify all patients with osteosarcomas in the lower humerus and distally between 1985 and 2012. Patient, tumor, treatment and outcome data was collected.

RESULTS

Twenty-six patients were included in this study. There were 9 males and 17 females with a mean age of 33 years (9-90). Seventeen osteosarcomas were located in the forearm bones (65%), six in the distal humerus (23%), and three (12%) in the hand. The three most common sub-diagnoses were parosteal 7/21 (33%), fibroblastic 4/21 (19%) and osteoblastic osteosarcomas 3/21 (14%). 2 patients (8%) had Paget's disease and 19 patients (73%) had high-grade tumors. Local excision was carried out in 12 patients (48%), 4 patients underwent endoprosthetic replacement (16%) and 9 underwent amputation (36%). The overall risk of local recurrence was 4% in our series. The five-year overall survival rate was 67%, with low tumor grade and parosteal type of osteosarcoma being positive predictors of survival.

CONCLUSION

This series has shown that patients with high-grade osteosarcomas of the upper distal extremities have a higher amputation risk than other limb sites but have favorable outcomes with limb-salvage surgery, comparable to other anatomical sites. Parosteal osteosarcomas in particular have a good prognosis.

Malignant degeneration of multilevel monostotic Paget's disease involving the thoracic spine: an unusual presentation

Paget's disease is the second most common metabolic bone disease after osteoporosis and is characterized by abnormal bone turnover and remodeling that can lead to pain, pathological fracture, bony deformity and nerve compression syndromes. The lumbar region is the most commonly affected site within the spine followed by the thoracic and cervical spine. Even though the spine is affected very commonly in Paget's disease, malignant degeneration is exceptionally rare. Multilevel monostotic spine involvement due to Paget's disease is very uncommon. An unusual clinico-radiological manifestation of multilevel thoracic Paget's disease with sarcomatous degeneration presenting as a neurosurgical emergency is reported with a pertinent review of the literature.

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.

Genetically engineered mouse models and human osteosarcoma

Osteosarcoma is the most common form of bone cancer. Pivotal insight into the genes involved in human osteosarcoma has been provided by the study of rare familial cancer predisposition syndromes. Three kindreds stand out as predisposing to the development of osteosarcoma: Li-Fraumeni syndrome, familial retinoblastoma and RecQ helicase disorders, which include Rothmund-Thomson Syndrome in particular. These disorders have highlighted the important roles of P53 and RB respectively, in the development of osteosarcoma. The association of OS with RECQL4 mutations is apparent but the relevance of this to OS is uncertain as mutations in RECQL4 are not found in sporadic OS. Application of the knowledge or mutations of P53 and RB in familial and sporadic OS has enabled the development of tractable, highly penetrant murine models of OS. These models share many of the cardinal features associated with human osteosarcoma including, importantly, a high incidence of spontaneous metastasis. The recent development of these models has been a significant advance for efforts to improve our understanding of the genetics of human OS and, more critically, to provide a high-throughput genetically modifiable platform for preclinical evaluation of new therapeutics.

Paget's Disease of Bone: A Review of Epidemiology, Pathophysiology and Management

Paget's disease of bone is a common disorder which may affect one or many bones. Although many patients are asymptomatic, a variety of symptoms and complications may occur. Fortunately, effective pharmacologic therapy, primarily with potent bisphosphonates, is now available to treat patients with complications or symptoms. This review of Paget's disease of bone will include epidemiology and pathophysiology, complications and clinical findings, indications for treatment, and the drugs currently available to treat this condition.

Late-onset fracture-associated osteosarcoma in a cat

An 18-year-old male, castrated Domestic Shorthaired cat was presented with the complaint of acute severe lameness of the left pelvic limb. There was no history of trauma, apart from a distal physeal left femoral fracture that had been repaired 17 years previously. Radiology revealed a displaced distal metaphyseal femoral fracture with marked areas of bone lysis and periosteal proliferations. A pathological fracture due to a bone neoplasia was suspected. An amputation with coxofemoral disarticulation was performed. Histopathology confirmed the tentative diagnosis of appendicular osteo-sarcoma. No postoperative complications were encountered and the cat made a full recovery. This case shows an unusual presentation of a late-onset fracture-associated feline osteosarcoma.

Imaging pattern of calvarial lesions in adults

Calvarial lesions often present themselves as clinically silent findings on skull radiographs or as palpable masses that may cause localized pain or soreness. This review aims to explore the radiographic, computed tomography (CT), and magnetic resonance imaging (MRI) characteristics of calvarial neoplastic, inflammatory, and congenital lesions that are common in adults in order to facilitate a structured approach to their diagnosis and limit the differential diagnosis. In addition to reviewing the literature, we reviewed the records of 141 patients of the Montreal Neurological Institute and Hospital with radiologically documented calvarial lesions between 2001 and June 2009. CT is ideal for detecting bony lesions and is helpful in precisely localizing a lesion pre-surgically. MRI is best at identifying intradiploic lesions before they affect the cortical tables and is able to establish extraosseous involvement, especially when paramagnetic contrast is employed.

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.

Dickkopf-1 as a potential therapeutic target in Paget's disease of bone

IMPORTANCE OF THE FIELD

Wnt signalling plays a role in maintaining healthy bone mass. Dickkopf-1 (DKK-1) is a soluble inhibitor of Wnt signalling and its excessive expression contributes to bone loss in rheumatoid arthritis and multiple myeloma. New therapeutics have been developed for treatment of these conditions that target DKK-1 expression. DKK-1 is elevated in serum of patients with Paget's disease of the bone (PDB) and evidence is accumulating for a role of DKK-1 in PDB.

AREAS COVERED IN THIS REVIEW

The role of Wnt signalling and DKK-1 in bone health and disease and the aetiology of PDB in the light of recent advances in understanding of Wnt signalling.

WHAT THE READER WILL GAIN

PDB is a disorder of unknown aetiology characterised by localised increase in unregulated bone remodelling resulting in osteolytic and osteosclerotic lesions. Evidence is adduced for the involvement of Wnt signalling, DKK-1 and osteoblasts in PDB pathogenesis.

TAKE HOME MESSAGE

At present there is no cure for PDB and the current treatment of choice are bisphosphonates. These treat the resorptive phase of PDB but do not prevent its return. We present a new perspective on the aetiology of PDB and speculate on DKK-1 as a therapeutic target.

Paget's disease of bone

Paget's disease of bone is a focal bone disorder that is common among older people of Western European descent. It is an unusual disorder, for although we now have safe and highly effective treatment, there are many aspects of its pathogenesis and natural history that we do not yet understand. Recent years have seen significant advances in the understanding of its epidemiology, genetics and molecular biology, but an integrated view that incorporates all these aspects remains elusive. In this review we examine some of the outstanding problems, the solutions to which seem likely to change our understanding of bone cell biology.