Osteoid osteoma and osteoblastoma: novel histological and immunohistochemical observations as evidence for a single entity

Osteoid osteoma appearing after bony fracture in a girl with osteogenesis imperfecta

Osteoid osteoma (OO) is a common, benign bone tumor. However, there are no case reports of OO associated with osteogenesis imperfecta (OI), or pathological fractures in OO. A 3-year-old girl with OI sustained a complete right tibial diaphyseal fracture. Bony fusion was completed after 4 months of conservative therapy; nevertheless, 18 months later spontaneous pain appeared at the fracture site, without any cause. Plain radiographs showed a newly apparent, rounded area of translucency 1 cm in diameter, just overlapping the previous fracture. Images obtained using three-dimensional time-resolved contrast-enhanced magnetic resonance angiography showed strong central enhancement in the early phase, with an apparent nidus, suggesting the diagnosis of OO. Nineteen months after the first fracture, while skipping, the patient refractured her tibial diaphysis at the site of the previous fracture. This is a very rare case of OO, apparently co-existing with OI and leading to a bony fracture. In our case, the combination of bone fragility in OI and a recent fracture at the site of the OO may have caused the re-fracture.

The malignant transformation of osteoid osteoma in the cervical spine to high-grade osteosarcoma: a case report and review of literature

PURPOSE

Osteoid osteoma occasionally occur in the spine, but their malignant transformation is not common. We present an extremely rare case of the malignant transformation of an osteoid osteoma to high-grade osteosarcoma that formed in the pedicle and spread to the lateral mass of the cervical spine.

CASE PRESENTATION

We report the case of an 18-year-old man who suffered from neck pain as an initial symptom. The size of the radiolucent lesion was 12 mm in diameter at the time of diagnosis. Intralesional tumour resection and autologous bone grafting were performed. The remaining tumour grew gradually for 40 months after the surgery; therefore, the tumour had grown rapidly till 51 months after the initial diagnosis. At this stage, the tumour size was approximately 6-fold larger than the initial size, and resulted in progressive paraplegia. A biopsy revealed that the tumour had transformed into a high-grade osteosarcoma. Heavy charged particle irradiation was performed to control tumour growth.

CONCLUSIONS

There is a possibility of malignant transformation of osteoid osteoma. Patients with osteoid osteoma or osteoblastoma should be carefully observed, especially for recurrent tumours after an intralesional resection.

Osteoid Osteoma of the Basilar Border of the Mandible: A Diagnostic Dilemma

Introduction. Osteoid osteoma is a benign osseous tumor characterized by an excessive formation of unmineralized bone matrix. The aim of this study was to present, through a case report, the clinical and radiological manifestations of osteoid osteoma affecting the left basilar border of the mandible. Observation. A 30-year-old male patient presented with left mandibular pain of unknown etiology. The chief complaint was mandibular pain accentuating mainly at night, originating in the left basilar border, and radiating to the whole mandibular hemi-arch. Extraoral examination revealed a small, bone-consistent, and slightly painful swelling. Computed tomography scan revealed a well-limited, infracentimetric, and mixed osteolytic image with central nidus and peripheral osteocondensation. Histological examination revealed osteoid osteoma. Surgical excision of the lesion was performed, and the pain stopped immediately. Discussion. This benign tumor presents many clinical and radiological features similar to other lesions. To differentiate osteoid osteoma from these other bone pathoses, practitioners should have a clear concept and keen observation skills. Confrontation of the clinical, radiological, and anatomopathological data is therefore essential to establish the correct diagnosis and to determine the appropriate treatment plan.

Fibro-Osseous Lesion of the Nose and Paranasal Sinus: A Retrospective Study With Literature Review

Background

Fibro-osseous (FO) lesions are slow-growing benign lesions in the paranasal sinuses. They include osteomas, fibrous dysplasia (FD), and ossifying fibro­ma (OF). Fibro-osseous (FO) lesions are frequently asymptomatic, and they are incidentally found on imaging. They are characterized by different histological, radiological, and clinical variants. Depending on symptoms, size, location, and extension, the treatment strategy varies significantly for these lesions.

Objective

We aim to compare the age, onset, gender, clinical presentation, postoperative improvement, and complications of a fibro-osseous lesion in the paranasal sinuses.

Methods

A retrospective analysis was done targeting patients diagnosed with benign fibro-osseous (FO) lesions, and the incidence among 403 patients who underwent functional endoscopic sinus surgery (FESS) at Aseer Central Hospital, Kingdom of Saudi Arabia, was reviewed from January 2013 to January 2022.

Results

A total of seven patients were found; five patients were diagnosed with osteoma, and two were diagnosed with fibrous dysplasia. There were no ossifying fibroma cases. The patients’ mean age was 25.5 ± 12.9 years old. Four (57.1%) patients were males, and three (42.9%) were females, with a male/female ratio of 1.25:1. The most common locations were the frontal sinus and ethmoid sinus, and the two cases of fibrous dysplasia involved almost all facial bones. The endonasal endoscopic approach was chosen to treat all seven patients.

Conclusions

There are differences in the onset age, location, and complications postoperatively among osteoma and fibrous dysplasia patients. Osteoma most commonly occurs in the frontal sinus, while fibrous dysplasia involved all facial bones in our study. Endoscopic surgery is currently the primary strategy for treatment.

Osteoblastoma and Osteoid Osteoma of the Mandible: Review of the Literature and Report of Two Cases

Osteoblastoma and osteoid osteoma are rare benign neoplasms of the jaws. We reviewed current literature surrounding the ongoing debate over similarities and differences of osteoblastoma and osteoid osteoma and present two cases. Both cases are well-demarcated mixed radiodensity mandibular lesions with histological features of osteoblastoma. They exhibit, however, distinctly unique and contrasting clinical and imaging characteristics suggesting that the first case is osteoblastoma and the second is osteoid osteoma. The first case of a 37-year-old male presents with a large, expansile lesion at posterior mandible, surrounded by a thick sclerotic band. Unusual features include significant buccal/lingual expansion, extensive new bone apposition, and soft tissue edema in the masseter muscle. This is in contrast to the second case of a much smaller lesion in a 17-year-old male with history of recent third molar extraction in the left posterior mandible. In this case, CT imaging revealed a circular, nonexpansile lesion with a sclerotic border surrounded by a radiolucent rim. Both patients underwent surgical excision of the lesion with extraction of the adjacent tooth. We discuss herein the distinct clinical and imaging features.

Benign Bone-Forming Tumors

Benign bone-forming tumors comprise osteomas, osteoid osteomas, and osteoblastomas. Osteomas affect a wide age range and are usually discovered incidentally. They occur predominantly in the craniofacial skeleton and are classically composed of compact bone. Osteoid osteomas and osteoblastomas are painful lesions occurring in young patients. They are morphologically similar and characterized by FOS gene rearrangement and c-FOS expression at a protein level. Osteoid osteomas are usually smaller than 2 cm in maximum dimension with limited growth potential; osteoblastomas are larger than 2 cm and may be locally aggressive. Histologically both are composed of anastomosing trabeculae of woven bone.

Osteoid osteoma: the great mimicker

Osteoid osteoma is a painful, benign and common bone tumor that is prevalent in young adults. The typical clinical presentation consists of pain that becomes worse at night and is relieved by nonsteroidal anti-inflammatory drugs. The most common imaging finding is a lytic lesion, known as a nidus, with variable intralesional mineralization, accompanied by bone sclerosis, cortical thickening and surrounding bone marrow edema, as well as marked enhancement with intravenous contrast injection. When the lesion is located in typical locations (intracortical bone and the diaphyses of long bones), both characteristic clinical and radiological features are diagnostic. However, osteoid osteoma is a multifaceted pathology that can have unusual presentations, such as intraarticular osteoid osteoma, epiphyseal location, lesions at the extremities and multicentric nidi, and frequently present atypical clinical and radiological manifestations. In addition, many conditions may mimic osteoid osteoma and vice versa, leading to misdiagnosis. Therefore, it is essential to understand these musculoskeletal diseases and their imaging findings to increase diagnostic accuracy, enable early treatment and prevent poor prognosis.

Full-Endoscopic Resection of Osteoid Osteoma in the Thoracic Spine: A Case Report

Common symptoms such as axial pain or nocturnal pain, associated with warning signs that are often worrisome in addition to nonspecific radiological findings, can characterize benign lesions in the spine, and osteoid osteoma is among them. We describe here a clinical case of a pediatric patient with an expansive bone lesion in the thoracic spine discovered after investigation for thoracic pain, mainly at night, which, despite a good response to simple analgesics, evolved in the short term with global spinal deformity. After a multidisciplinary evaluation, she underwent surgical resection using a pioneering endoscopic technique that allowed the definitive anatomopathological diagnosis of osteoid osteoma and guaranteeing very satisfactory treatment and evolution. Although there are already several therapeutic techniques described and with good results in specific cases of osteoid osteomas and other benign neoplastic lesions of the spine, full-endoscopic resection appears as an innovative and potentially promising option for diagnosis and treatment, especially since it is a safe, effective, and not too morbid intervention.

Typical and Atypical Radiographic Features of Symptomatic Osteoblastoma in the Spine

BACKGROUND

Spine osteoblastomas (OBs) are relatively rare. In contrast to osteoid osteoma, radiologic and clinical manifestations of OB can be varied and atypical. Typical radiographic features in spinal OB include peritumoral bone sclerosis, bone marrow edema, and soft tissue edema. Atypical radiographic features include lesions involving ≥3 segments, lesions with extensive (≥3 segments) bone sclerosis, excessive edema (≥3 segments) of soft tissue and bone marrow, no intralesional calcification, and location in the vertebral body only. The aim of this study was to identify typical and atypical features of OB.

METHODS

Pretreatment computed tomography scans and magnetic resonance imaging were reviewed retrospectively. Percutaneous biopsies were performed to confirm pathology in atypical cases.

RESULTS

A total of 50 images from patients with diagnosed OB were reviewed. Atypical radiographic features were found in 18 cases (36%). Pathologic diagnosis was confirmed as OB in 86.2% (25/29) cases after percutaneous computed tomography-guided biopsy.

CONCLUSIONS

Our results show that >30% of spinal OB cases might have atypical radiographic features. In cases with atypical radiographic features, computed tomography-guided biopsies are recommended.

The one-in-all diagnostic value of 99mTc-MDP bone scan combining with single-photon emission tomography (SPECT)/CT imaging in spinal osteoblastoma

BACKGROUND

Osteoblastoma (OB) is an intermediate lesion, which makes the accurate preoperative diagnosis very important. ^99mTc-methylene diphosphonate (^99mTc-MDP) bone scan and SPECT/CT imaging were evaluated for their diagnostic value in spinal OB.

METHODS

This study was a retrospective analysis of patients with spinal OB lesions confirmed by pathology and diagnosed with bone scan and SPECT/CT for preoperative diagnosis from January 2008 to December 2018. The uptake levels of OB on planar bone scan were divided into low, medium, and high groups by visual assessment referring to the uptake of the normal rib, spine, and bladder. X-ray, CT, MRI, bone scan, and SPECT/CT imaging of the patients were analyzed for characteristics summary.

RESULTS

Twenty-five patients were diagnosed for spinal OB (17 males and 8 females with a proportion of 2.1:1), and the average age was 26.8 ± 10.8 years (range 5~59). There were 8 lesions located in the cervical, 6 in the thoracic, and 11 in the lumbar vertebrae. Twenty-four lesions involved posterior elements, especially the pedicles (14/25). Symptoms were predominantly painful with a duration of 18.3 ± 13.9 months (range 0.5~60 months). The lesion size ranged from 9 to 35 mm. All the lesions were low to high uptake in the planar bone scan, and the percentages of low to high levels were 1 (4%), 8 (32%), and 16 (64%) cases.

CONCLUSIONS

Spinal OB mainly involved the posterior area, and elderly patients should be considered as well. SPECT/CT combined the characteristics of bone uptake and anatomical features of bone tumors, proving its one-in-all diagnostic value for spinal OB and other osteogenic tumors.

Osteoblastoma of the clavicle at the site of a previous fracture-first case report and review of the literature

Osteoblastoma is a rare, benign primary tumor of bone, accounting for < 1% of all bone tumors. We report the case of a 27-year-old female who developed pain and swelling five and a half years after a clavicular fracture and was subsequently found to have an osteoblastoma arising at the fracture site. This is the first reported case of an osteoblastoma developing after a fracture, although osteoid osteomas, which are histologically indistinguishable from osteoblastomas, have been reported at prior fracture sites. This report demonstrates that secondary neoplasms such as osteoblastomas should be considered in the differential diagnosis for pain at a healed fracture site recurring years after the initial trauma.

Osteoblastoma in the Distal Humerus of a Cat

A 7-year-old neutered male domestic shorthair cat was presented with chronic lameness in the right forelimb. A cystic bony lesion was identified in the distal right humerus and amputation was performed. The epiphyseal trabecular bones of the capitulum and trochlea was replaced by a tan to pink, expansile mass that was surrounded by a thin rim of cortical bone. Microscopically, the tumour was composed of a bland, osteoid producing spindle cell population within a well-vascularized fibrous stroma. Radiographical and histological features were consistent with osteoblastoma. Osteoblastoma and the related osteoid osteoma are uncommon, benign osteoblastic tumours that are reported rarely in animals. These tumours should be considered as differential diagnoses for slow growing, cystic bony lesions in cats.

Intra-articular osteoid osteoma of tempromandibular joint: A case report

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Osteoid osteoma is a benign bone neoplasm, with significant nocturnal pain that responds to NSAIDs.

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A case of an intra-articular osteoid osteoma involving the articular eminence and glenoid fossa of TMJ in a 46-years-old female is reported.

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CT scan imaging is helpful in displaying the typical radiographic features and localization of the lesion.

Introduction

An osteoid osteoma is a benign bone neoplasm with limited growth potential, characterized by significant nocturnal pain that usually responds to non-steroidal anti-inflammatory drugs (NSAIDs). The tumor may occur in any part of the skeleton, most commonly in the lower extremities and vertebrae.

Presentation of case

A 46-year-old female was diagnosed with a rare case of an intra-articular variant of osteoid osteoma, involving the articular eminence and glenoid fossa of the temporo-mandibular joint (TMJ).

Discussion

The tumor presented as a painful progressive swelling in the right pre-auricular area that had lasted for more than 2 years and which had been previously treated as a TMJ disorder. Computed tomography revealed a well-defined heterogeneous nidus involving the articular eminence of the TMJ. Surgical excision was performed and histological examination confirmed the diagnosis. In this article, in addition to describing the case, all cases of osteoid osteoma of the jaws and TMJ reported in the English-language literature are reviewed.

Conclusion

Osteoid osteoma involving the TMJ is a rare presentation and may exhibit ambiguous symptoms, which could lead to misdiagnosis and delayed treatment.

A Case Report on Gardner Syndrome With Dental Implant Treatment and a Long-Term Follow-Up

A case of Gardner syndrome (GS) in a 37-year-old woman is presented in which rehabilitation with dental implant treatment was followed for 7 years. The course of diagnostics and treatment is followed through an overview of 45 tissue biopsy and cytology samples during a period of 30 years. The patient was diagnosed with GS after a routine review of an oral panoramic radiograph presenting with multiple osteomas and multiple unerupted supernumerary teeth. Biopsy results and surgical procedures with histopathologic diagnoses from 1986 to 2016 are presented. Histologic analysis of the sampled jawbone showed a picture similar to an osteoid osteoma. The installed implant was functionally stable, with no clinical or radiographic events observed at yearly visits, for 7 years. In 1991, benign tumors appeared; in 2014, multiple adenomas were found in the small intestine and rectum. This case report shows the potential for dental implant treatment in a patient with GS.

Benign osteoblastoma of the palate: a rare clinical presentation

Osteoblastoma is a rare, benign type of osteoblastic tumor. It constitutes approximately 1% of all primary bone tumors. Osteoblastoma most commonly affects the long bones; it very rarely affects the jaw bones. Because of its clinical and histological similarity with other bony tumors, such as osteoid osteoma and fibro-osseous lesions, osteoblastoma is a diagnostic challenge. Very few cases of osteoblastoma involving the maxillofacial region have been reported to date. We herein describe a 15-year-old female patient with osteoblastoma that presented as a palatal swelling of 6 months' duration.

Case of Spinal Osteoblastoma in Elderly: Is It Really a Young Patient's Disease?

BACKGROUND

Osteoblastoma is a benign bone-forming tumor, sometimes locally invasive, that may involve any bone. The highest incidence is between 20 and 30 years of age, and there are no cases described in the elderly.

METHODS

We report a case of an elderly patient with a lesion in the lumbar spine in which osteoblastoma diagnosis was made.

CONCLUSIONS

Osteoblastoma is a rare tumor older than 50 years of age, but it should be considered in the differential diagnosis of bone lesions of the spine in adulthood and in the elderly, to avoid a delay in the treatment.

Imaging Diagnosis of Solitary Tumors of the Phalanges and Metacarpals of the Hand

OBJECTIVE

Tumors and tumorlike lesions of the tubular bones of the hand, often incidentally discovered lesions, present a unique but challenging differential diagnosis.

CONCLUSION

Imaging, including both radiography and cross-sectional imaging, can allow the radiologist to generate a clinically useful differential diagnosis based on the distinguishing features of these entities. Recognition of these lesions is important because clinical management and treatment by orthopedic oncologists vary depending on the diagnosis.

Do Osteoblastoma and Osteoid Osteoma Represent the Same Pathologic Entity?: A Case Report and Review of the Recent Literature

CASE

We present the case of a fourteen-year-old boy with a benign diaphyseal femoral lesion that initially fulfilled the diagnostic criteria for osteoid osteoma but rapidly progressed and was finally diagnosed as osteoblastoma.

CONCLUSION

Clinical and radiographic criteria provide imperfect and somewhat arbitrary distinguishing features between osteoid osteoma and osteoblastoma. Although previous work highlighted the importance of histologic interpretation in this regard, recent comparative histologic and immunohistochemical evaluations failed to differentiate the two. We conclude that consideration should be given to the classification of osteoid osteoma and osteoblastoma as the same pathologic entity, with treatment based on presentation along a continuum of aggressiveness, and that future directions for study may include identification of factors predictive of progression and/or recurrence.

Bone- and cartilage-forming tumors and ewing sarcoma: an update with a gnathic emphasis

Over the past decade, there have been remarkable advances in bone tumor pathology. Insights into the genetic basis and pathobiology of many tumor types have impacted diagnosis, classification, and treatment. However, because gnathic lesions may comprise only a small proportion of cases overall for many tumors, clinicopathologic features and management considerations specific to this subset may be overlooked. Here we provide a summary of recent developments in the following tumor types: osteosarcoma (OS), chondrosarcoma (CS), osteoid osteoma (OO), osteoblastoma (OB), and Ewing sarcoma (ES). In particular, we will give special consideration to cases arising in the jaws.

Clinical and morphological characteristics of osteoid osteoma and osteoblastoma: a retrospective single-center analysis of 204 patients

Osteoid osteoma and osteoblastoma are histologically similar, benign bone-forming tumors. In this retrospective study, we aimed to evaluate the natural history; clinical, pathologic, and radiologic findings; and treatment results in 204 patients between 1959 and 2006 in a single institution. According to the World Health Organization's definition, tumors ≤1 cm in diameter were classified as osteoid osteoma, and those ≥2 cm, as osteoblastoma. For tumors between 1 cm and 2 cm, other criteria, such as the bone involved, the site, the presence of a nidus, and presence of peripheral sclerosis, were used for diagnosis. There were 131 patients with osteoid osteoma (93 male, 38 female) and 73 patients with osteoblastoma (40 male, 33 female). The mean age in the osteoid osteoma and osteoblastoma groups was 16.4 ± 7 and 19.6 ± 9.9 years, respectively. The osteoid osteoma cases were mostly localized in the extremities, whereas the osteoblastoma cases involved the vertebral column and sacrum. The nidus size varied between 0.2 and 1.5 cm in osteoid osteoma cases, and the tumor size range was 1.3-10 cm in the osteoblastoma cases. The pain was encountered in 89% of osteoid osteoma and 45% of osteoblastoma patients. Histopathology was similar in both cases. The treatment of choice was conservative surgery for both diagnoses. In conclusion, osteoblastoma is clinically and radiologically more aggressive than osteoid osteoma.

Is pain duration associated with morphologic changes of osteoid osteomas at CT?

PURPOSE

To assess the morphologic changes of osteoid osteomas on computed tomographic (CT) scans in association with pain duration.

MATERIALS AND METHODS

Institutional review board approval was obtained. Informed consent was waived. From January 2008 to December 2012, 235 patients were treated with interstitial laser ablation at the Hôpital Lariboisière. Ninety-six patients with histopathologically proven osteoid osteomas, complete clinical files, and CT data were studied retrospectively. The following variables were assessed: age, sex, bone location, bone segment, location of the osteoid osteoma in relation to the native cortex, nidus area, nidus calcification area and attenuation at CT, and nidus mineralization ratio (percentage of the calcification area over the total nidus area). Analysis of variance, Kaplan-Meier method, and Cox multivariate regression model were used for statistical analyses.

RESULTS

The study sample consisted of 96 patients, 68 of whom were male (71%) and 28 of whom were female (29%) (ratio of male to female patients, 2.4:1). Mean age ± standard deviation was 22.2 years ± 10.4 (range, 4-54 years; median, 18.5 years). The patients' age and nidus mineralization ratio increased significantly with pain duration (hazard ratio, 0.975 [P = .031] and 0.193 [P = .007], respectively). No significant association was found between pain duration and other variables, including the nidus area. In long bones, diaphyseal osteoid osteomas were significantly less mineralized than those in other locations (P = .009).

CONCLUSION

The nidus mineralization ratio of osteoid osteomas increases significantly with pain duration and may be a marker of tumor age. Diaphyseal osteoid osteomas demonstrate a lower ratio of nidus mineralization. At the onset of symptoms, older patients experience pain for a longer period before treatment.